Dissertations / Theses: 'High Voltage Power Supply (HVPS)'

1

Beikoff, Geoffrey Noel. "A high power, high voltage switching power supply." Thesis, Queensland University of Technology, 1992. https://eprints.qut.edu.au/36226/1/36226_Beikoff_1992.pdf.

Full text

Abstract:

A switching power supply to drive magnetrons for microwave heating has been designed, prototyped and tested. The magnetron has an rf power output of 6000 watts and requires a DC voltage of 7200 volts at a current of approximately 1.1 amps for a power input to the magnetron of 8000 watts. Six magnetrons are to be connected per railway tanker for heating the tankers at a railway terminus. The power supply has been designed for small size, efficiency and reliability. Current technology has been used. Insulated Gate Bipolar Transistors (IGBT) and power MOSFETs, both of moderately high current and voltage ratings, have been used at 25 kHz and 50 kHz switching frequencies respectively. MOSFETs of 20 amps and 500 volts and IGBT's of 40 amps and 600 volts ratings have been used. Ferrites for use at high switching frequencies have been used for transformers and iron powder material has been used for energy storage inductors. High quality insulating materials have been used to achieve the high voltage insulation requirements. Kapton, PTFE, mylar and nylon have been used where appropriate. Special features of the power supply include the power factor correction first stage, the use of the higher than normal leakage inductance of the power converter second stage transformer to make a resonant converter and the ripple cancelling effect of the series connection of the units on each phase. The power factor correction meets I EC 555 and AS2279 standards for harmonic content on the power supply source. The resonant converter yields zero load current switching of the converter transistors. The output 100 Hz ripple on the 7200 volt supply is negligible because of the series connection of the three outputs.

APA, Harvard, Vancouver, ISO, and other styles

2

Zabihi, Sasan. "Flexible high voltage pulsed power supply for plasma applications." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/48137/1/Sasan_Zabihi_Sheykhrajeh_Thesis.pdf.

Full text

Abstract:

Demands for delivering high instantaneous power in a compressed form (pulse shape) have widely increased during recent decades. The flexible shapes with variable pulse specifications offered by pulsed power have made it a practical and effective supply method for an extensive range of applications. In particular, the release of basic subatomic particles (i.e. electron, proton and neutron) in an atom (ionization process) and the synthesizing of molecules to form ions or other molecules are among those reactions that necessitate large amount of instantaneous power. In addition to the decomposition process, there have recently been requests for pulsed power in other areas such as in the combination of molecules (i.e. fusion, material joining), gessoes radiations (i.e. electron beams, laser, and radar), explosions (i.e. concrete recycling), wastewater, exhausted gas, and material surface treatments. These pulses are widely employed in the silent discharge process in all types of materials (including gas, fluid and solid); in some cases, to form the plasma and consequently accelerate the associated process. Due to this fast growing demand for pulsed power in industrial and environmental applications, the exigency of having more efficient and flexible pulse modulators is now receiving greater consideration. Sensitive applications, such as plasma fusion and laser guns also require more precisely produced repetitive pulses with a higher quality. Many research studies are being conducted in different areas that need a flexible pulse modulator to vary pulse features to investigate the influence of these variations on the application. In addition, there is the need to prevent the waste of a considerable amount of energy caused by the arc phenomena that frequently occur after the plasma process. The control over power flow during the supply process is a critical skill that enables the pulse supply to halt the supply process at any stage. Different pulse modulators which utilise different accumulation techniques including Marx Generators (MG), Magnetic Pulse Compressors (MPC), Pulse Forming Networks (PFN) and Multistage Blumlein Lines (MBL) are currently employed to supply a wide range of applications. Gas/Magnetic switching technologies (such as spark gap and hydrogen thyratron) have conventionally been used as switching devices in pulse modulator structures because of their high voltage ratings and considerably low rising times. However, they also suffer from serious drawbacks such as, their low efficiency, reliability and repetition rate, and also their short life span. Being bulky, heavy and expensive are the other disadvantages associated with these devices. Recently developed solid-state switching technology is an appropriate substitution for these switching devices due to the benefits they bring to the pulse supplies. Besides being compact, efficient, reasonable and reliable, and having a long life span, their high frequency switching skill allows repetitive operation of pulsed power supply. The main concerns in using solid-state transistors are the voltage rating and the rising time of available switches that, in some cases, cannot satisfy the application’s requirements. However, there are several power electronics configurations and techniques that make solid-state utilisation feasible for high voltage pulse generation. Therefore, the design and development of novel methods and topologies with higher efficiency and flexibility for pulsed power generators have been considered as the main scope of this research work. This aim is pursued through several innovative proposals that can be classified under the following two principal objectives. • To innovate and develop novel solid-state based topologies for pulsed power generation • To improve available technologies that have the potential to accommodate solid-state technology by revising, reconfiguring and adjusting their structure and control algorithms. The quest to distinguish novel topologies for a proper pulsed power production was begun with a deep and through review of conventional pulse generators and useful power electronics topologies. As a result of this study, it appears that efficiency and flexibility are the most significant demands of plasma applications that have not been met by state-of-the-art methods. Many solid-state based configurations were considered and simulated in order to evaluate their potential to be utilised in the pulsed power area. Parts of this literature review are documented in Chapter 1 of this thesis. Current source topologies demonstrate valuable advantages in supplying the loads with capacitive characteristics such as plasma applications. To investigate the influence of switching transients associated with solid-state devices on rise time of pulses, simulation based studies have been undertaken. A variable current source is considered to pump different current levels to a capacitive load, and it was evident that dissimilar dv/dts are produced at the output. Thereby, transient effects on pulse rising time are denied regarding the evidence acquired from this examination. A detailed report of this study is given in Chapter 6 of this thesis. This study inspired the design of a solid-state based topology that take advantage of both current and voltage sources. A series of switch-resistor-capacitor units at the output splits the produced voltage to lower levels, so it can be shared by the switches. A smart but complicated switching strategy is also designed to discharge the residual energy after each supply cycle. To prevent reverse power flow and to reduce the complexity of the control algorithm in this system, the resistors in common paths of units are substituted with diode rectifiers (switch-diode-capacitor). This modification not only gives the feasibility of stopping the load supply process to the supplier at any stage (and consequently saving energy), but also enables the converter to operate in a two-stroke mode with asymmetrical capacitors. The components’ determination and exchanging energy calculations are accomplished with respect to application specifications and demands. Both topologies were simply modelled and simulation studies have been carried out with the simplified models. Experimental assessments were also executed on implemented hardware and the approaches verified the initial analysis. Reports on details of both converters are thoroughly discussed in Chapters 2 and 3 of the thesis. Conventional MGs have been recently modified to use solid-state transistors (i.e. Insulated gate bipolar transistors) instead of magnetic/gas switching devices. Resistive insulators previously used in their structures are substituted by diode rectifiers to adjust MGs for a proper voltage sharing. However, despite utilizing solid-state technology in MGs configurations, further design and control amendments can still be made to achieve an improved performance with fewer components. Considering a number of charging techniques, resonant phenomenon is adopted in a proposal to charge the capacitors. In addition to charging the capacitors at twice the input voltage, triggering switches at the moment at which the conducted current through switches is zero significantly reduces the switching losses. Another configuration is also introduced in this research for Marx topology based on commutation circuits that use a current source to charge the capacitors. According to this design, diode-capacitor units, each including two Marx stages, are connected in cascade through solid-state devices and aggregate the voltages across the capacitors to produce a high voltage pulse. The polarity of voltage across one capacitor in each unit is reversed in an intermediate mode by connecting the commutation circuit to the capacitor. The insulation of input side from load side is provided in this topology by disconnecting the load from the current source during the supply process. Furthermore, the number of required fast switching devices in both designs is reduced to half of the number used in a conventional MG; they are replaced with slower switches (such as Thyristors) that need simpler driving modules. In addition, the contributing switches in discharging paths are decreased to half; this decrease leads to a reduction in conduction losses. Associated models are simulated, and hardware tests are performed to verify the validity of proposed topologies. Chapters 4, 5 and 7 of the thesis present all relevant analysis and approaches according to these topologies.

APA, Harvard, Vancouver, ISO, and other styles

3

Weiser, Nicholas. "Dual High-Voltage Power Supply for use On Board a CubeSat." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1204.

Full text

Abstract:

Since their conception in 1999, CubeSats have come and gone a long way. The first few that went into space were more of a “proof of concept,” and were more focused on sending simple data and photographs back to Earth. Since then, vast improvements have been made by over 40 universities and private firms, and now CubeSats are beginning to look towards interplanetary travel. These small satellites could provide a cost effective means of exploring the galaxy, using off the shelf components and piggy-backing on other launch vehicles with more expensive payloads. However, CubeSats are traditionally launched into Low Earth Orbit (LEO), and if an interplanetary satellite is to go anywhere from there, it will need a propulsion system. This thesis project’s main goal will be to investigate the possibility and capability of an Ion-Spray propulsion system. Several problems are to be tackled in this project: how to take a 9 V supply and boost it to a maximum potential difference of 5,000 V, all while minimizing the noise and testing the feasibility of such a system being flown on board a CubeSat.

APA, Harvard, Vancouver, ISO, and other styles

4

Jacobs, D. M. (Danver Maxwill). "Voltage control of medium to high power three-phase inverter supply systems." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52608.

Full text

Abstract:

Thesis (MScEng)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: In this thesis a new voltage control method is developed for a three-phase inverter supply system. The inverter supply system consist of a Permanent Magnet Generator, a three-phase rectifier, a three-phase inverter plus LC-filter and a three-phase transformer in series. This system supplies power to a network or to a stand-alone load. The main focus of this thesis is on the control aspects of the inverter and the LC-filter. Different voltage control systems are investigated and compared to each other. From these methods the proposed voltage control method is developed where only the output voltages are measured to establish good voltage control. All these voltage control methods are also simulated with a software package. The proposed voltage control method compares very well with other voltage control methods. The results that are obtained in the simulations are satisfactory. The proposed voltage control method is also implemented in an 8 kW laboratory scale model and, again, very good practical results are obtained. A TMS320F240 nsp controller is used to implement the proposed voltage control method. The controller compensates well for load steps, and these results compare well to an alternative voltage control method, which was also evaluated practically.
AFRIKAANSE OPSOMMING: In hierdie tesis IS 'n nuwe spanningsbeheermetode ontwikkel VIr 'n drie-fase wisselrigter kragtoevoerstelsel. Die wisselrigter kragtoevoerstelsel bestaan uit 'n Permanent Magneet Generator, 'n drie-fase gelykrigter, 'n drie-fase wisselrigter plus Le-filter, en 'n drie-fase transformator in serie. Hierdie stelsel voorsien krag aan 'n netwerk sowel as aan 'n alleenstaande las. Die hooffokus van hierdie tesis is op die beheeraspekte van die wisselrigter en Le-filter. Verskillende spanningsbeheermetodes is deeglik ondersoek en vergelyk met mekaar. Uit hierdie metodes is dan die voorgestelde beheermetode ontwikkel waar slegs die uittreespanning gemeet word om goeie spanningsbeheer te kan doen. Al hierdie spanningsbeheermetodes is dan gesimuleer met 'n sagteware pakket. Die voorgestelde spanningsbeheermetode vergelyk baie goed met die ander spanningsbeheermetodes. Die resultate verky in die simulasies is ook baie bevredigend. Die voorgestelde beheermetode is ook geïmplementeer op 'n 8 kW laboratorium skaalmodel en weereens is baie goeie praktiese resultate verky. 'n TMS320F240 DSP-beheerder is gebruik om die voorgestelde beheermetode mee te implementeer. Die beheerder kompenseer baie goed vir lastrappe en vergelyk ook goed met 'n ander spanningsbeheermetode wat prakties ge-evalueer is.

APA, Harvard, Vancouver, ISO, and other styles

5

Myhre, Jørgen Chr. "Electrical Power Supply to Offshore Oil Installations by High Voltage Direct Current Transmission." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-383.

Full text

Abstract:

This study was initiated to investigate if it could be feasible to supply offshore oil installations in the North Sea with electrical power from land. A prestudy of alternative converter topologies indicated that the most promising solution would be to investigate a conventional system with reduced synchronous compensator rating.

The study starts with a summary of the state of power supply to offshore installations today, and a short review of classical HVDC transmission. It goes on to analyse how a passive network without sources influences the inverter. The transmission, with its current controlled rectifier and large inductance, is simulated as a current source. Under these circumstances the analysis shows that the network frequency has to adapt in order to keep the active and reactive power balance until the controllers are able to react. The concept of firing angle for a thyristor is limited in a system with variable frequency, the actual control parameter is the firing delay time.

Sensitivity analysis showed some astonishing consequences. The frequency rises both by an increase in the active and in the reactive load. The voltage falls by an increase in the active load, but rises by an increase in the inductive load.

Two different control principles for the system of inverter, synchronous compensator and load are defined. The first takes the reference for the firing delay time from the fundamental voltage at the point of common coupling. The second takes the reference for the firing delay time from the simulated EMF of the synchronous compensator. Of these, the second is the more stable and should be chosen as the basis for a possible control system.

Two simulation tools are applied. The first is a quasi-phasor model running on Matlab with Simulink. The other is a time domain model in KREAN. The time domain model is primarily used for the verification of the quasi-phasor model, and shows that quasi-phasors is still a valuable tool for making a quick analysis of the main features when the details of the transients are of less importance.

The study indicates that power supply by HVDC transmission from land to offshore oil installations could be technically feasible, even without the large synchronous compensators normally required. It has been shown that in a network only supplied by an inverter, variations of active and reactive loads have significant influence on both voltage and frequency. Particularly it should be noted that the frequency shows a positive sensitivity to increases in load. This could make the system intrinsically unstable in the case of a frequency dependent load such as motors.

It was not a part of the study to optimize controllers, but even with simple controllers it was possible to keep the frequency within limits given by norms and regulations, but the voltages were dynamically outside the limits, though not very far. These voltage overswings take place in the first few instances after a disturbance, so it takes unrealistically fast controllers to handle them. They are partly due to the model, where the land based rectifier and the DC reactors are simulated by a constant current source, but partly they have to be handled by overdimensioning of the system.

The simulations indicate that it should be technically possible to supply an oil platform with electrical power from land by means of HVDC transmission with small synchronous compensators. Whether this is financially feasible has not been investigated. Neither has it been considered whether the necessary equipment can actually be installed on an oil platform.

Recently both ABB and Siemens have presented solutions for HVDC transmission in the lower and medium power range based on voltage source converters based on IGBTs. Fully controllable voltage source HVDC converters have properties that may be better suited than conventional line commutated current source thyristor inverters, to supply weak or passive networks, such as offshore oil installations, with electrical power. But they also have some disadvantages, and a complete technical and financial comparison must be performed in order to decide about any potential project.

APA, Harvard, Vancouver, ISO, and other styles

6

Devine, Phillip John. "A controllable, variable waveform, high voltage, switched mode power supply for electrostatic precipitators." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/30176.

Full text

Abstract:

Increased awareness of the effects of atmospheric pollution has meant that electrostatic precipitators, which have been used since the early part of this century to separate particulate matter from process gas streams, are now required to achieve particulate collection efficiencies in excess of 99.7% for a number of processes. Increasingly stringent legislation concerning industrial particulate emissions has challenged the precipitation industry to consider how equipment can be improved to reduce, in particular, heavy metal and respirable size particulate discharges. Electrostatic precipitators charge dust particles in a gas stream by corona-producing electrodes, and remove the charged particles by electrostatic attraction under high electric fields. This thesis details the development of a prototype high frequency (20KHz), high voltage (50kV), high power (25 kW) switched mode precipitator power supply with technological advances over conventional units. A high frequency, high voltage, high power precipitator supply using high frequency inverter technology coupled to a novel ferrite cored, high voltage transformer-rectifier unit has been designed and built. It is capable of delivering in a controlled and responsive way 25kW at 50kV into a load that may suffer from sparking and flashover. The developmental stages of the prototype from initial concept through to field trials of the supply at a power station in the UK are detailed.

APA, Harvard, Vancouver, ISO, and other styles

7

Fu, Dianbo. "Improved Resonant Converters with a Novel Control Strategy for High-Voltage Pulsed Power Supplies." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/34432.

Full text

Abstract:

The growing demand for high voltage, compact pulsed power supplies has gained great attention. It requires power supplies with high power density, low profile and high efficiency. In this thesis, topologies and techniques are investigated to meet and exceed these challenges. Non-isolation type topologies have been used for this application. Due to the high voltage stress of the output, non-isolation topologies will suffer severe loss problems. Extremely low switching frequency will lead to massive magnetic volume. For non-isolation topologies, PWM converters can achieve soft switching to increase switching frequency. However, for this application, due to the large voltage regulation range and high voltage transformer nonidealities, it is difficult to optimize PWM converters. Secondary diode reverse recovery is another significant issue for PWM techniques. Resonant converters can achieve ZCS or ZVS and result in very low switching loss, thus enabling power supplies to operate at high switching frequency. Furthermore, the PRC and LCC resonant converter can fully absorb the leakage inductance and parasitic capacitance. With a capacitive output filter, the secondary diode will achieve natural turn-off and overcome reverse recovery problems. With a three-level structure, low voltage MOSFETs can be applied for this application. Switching frequency is increased to 200 kHz. In this paper, the power factor concept for resonant converters is proposed and analyzed. Based on this concept, a new methodology to measure the performance of resonant converters is presented. The optimal design guideline is provided. A novel constant power factor control is proposed and studied. Based on this control scheme, the performance of the resonant converter will be improved significantly. Design trade-offs are analyzed and studied. The optimal design aiming to increase the power density is investigated. The parallel resonant converter is proven to be the optimum topology for this application. The power density of 31 W/inch3 can be achieved by using the PRC topology with the constant power factor control.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

8

GARCIA, ORDÓÑEZ LUIS GUILLERMO. "High Voltage Power Supply System and Front-End DAQ on FPGA/SoC for High Energy Particle Detectors." Doctoral thesis, Università degli Studi di Trieste, 2022. http://hdl.handle.net/11368/3030919.

Full text

Abstract:

High energy physics experiments are based on complex detectors built with novel techniques frequently configured in multichannel arrays. This complexity creates the need for custom-made related instrumentation and methods not often found in commercial devices. The research activity presented in this thesis aims at developing a distributed High Voltage Power Supply System (HVPSS) network for hybrid Micro-pattern Gaseous Detectors (MPGD) like the ones used in the RICH-1 detector of the COMPASS experiment at CERN. The hardware design was tested in several conditions including test beams at CERN in the SPS H4 beam line and with nuclear sources in the RD51 laboratory. The modular design as well as the reconfigurable capacity of the SoC-FPGA opened the possibility of using the HVPSS as a tool for other experiments. With few modifications, the system was successfully tested as a front-end Data Acquisition (DAQ) system for Water Cherenkov Detectors (WCD) in the context of indirect measurements of cosmic rays. Additional algorithms were implemented for online particle classification based on pulse-shape discrimination techniques. This thesis describes the basic concepts of the physics behind these detectors, as well as the electronics used for high energy particle detectors. It is followed by the most relevant aspects of the design process for the HVPSS and its modifications leading to the DAQ for WCDs. A description of the specific techniques developed for these applications and the most significant tests and results obtained during the research process are also presented.
High energy physics experiments are based on complex detectors built with novel techniques frequently configured in multichannel arrays. This complexity creates the need for custom-made related instrumentation and methods not often found in commercial devices. The research activity presented in this thesis aims at developing a distributed High Voltage Power Supply System (HVPSS) network for hybrid Micro-pattern Gaseous Detectors (MPGD) like the ones used in the RICH-1 detector of the COMPASS experiment at CERN. The hardware design was tested in several conditions including test beams at CERN in the SPS H4 beam line and with nuclear sources in the RD51 laboratory. The modular design as well as the reconfigurable capacity of the SoC-FPGA opened the possibility of using the HVPSS as a tool for other experiments. With few modifications, the system was successfully tested as a front-end Data Acquisition (DAQ) system for Water Cherenkov Detectors (WCD) in the context of indirect measurements of cosmic rays. Additional algorithms were implemented for online particle classification based on pulse-shape discrimination techniques. This thesis describes the basic concepts of the physics behind these detectors, as well as the electronics used for high energy particle detectors. It is followed by the most relevant aspects of the design process for the HVPSS and its modifications leading to the DAQ for WCDs. A description of the specific techniques developed for these applications and the most significant tests and results obtained during the research process are also presented.

APA, Harvard, Vancouver, ISO, and other styles

9

Yang, Gang. "Design of a High Efficiency High Power Density DC/DC Converter for Low Voltage Power Supply in Electric and Hybrid Vehicles." Thesis, Supélec, 2014. http://www.theses.fr/2014SUPL0011/document.

Full text

Abstract:

Cette thèse traite de la conception d’un convertisseur DC / DC destiné aux véhicules électriques et hybrides (2,5 kW, 400V/14V, 250kHz). Dérivé de la topologie LLC à résonance, ce convertisseur bénéficie des nombreux avantages propres à cette structure particulière. C’est ainsi que le prototype réalisé présente un rendement très élevé, une densité de puissance très forte avec des perturbations EMI très réduites. La première partie de cette thèse est consacrée à l’analyse théorique du circuit LLC afin de dégager un modèle de conversion et une stratégie de contrôle adaptée à l’application visée. Afin de conserver un rendement important sur une large plage de charge, une structure basée sur la mise en parallèle de deux modules LLC est proposée. Une nouvelle stratégie de contrôle à deux boucles est également proposée pour équilibrer le courant entre les deux modules. La seconde partie de la thèse fait appel à la simulation et à l’expérimentation. Il s’agit de minimiser la masse et l’encombrement tout en maximisant le rendement. Un composant magnétique spécial est conçu puis dimensionné pour intégrer le transformateur et diverses inductances de résonance. Ce convertisseur met également en œuvre un système de redressement synchrone robuste avec une compensation de phase, un module de puissance avec une résistance thermique très faible et un système de refroidissement efficace par air. Le rendement maximal mesuré est 95%. Le rendement demeure supérieur à 94% sur une plage de puissance s’étalant de 500 W à 2 kW. La densité de puissance est 1W/cm3. La CEM du convertisseur est développée dans cette thèse
In this dissertation, a 2.5kW 400V/14V, 250kHz DC/DC converter prototype is developed targeted for electric vehicle/hybrid vehicle applications. Benefiting from numerous advantages brought by LLC resonant topology, this converter is able to perform high efficiency, high power density and low EMI. A first part of this dissertation is the theoretical analysis of LLC: topology analysis, electrical parameter calculation and control strategy. To arrange high output current, this thesis proposes parallel connected LLC structure with developed novel double loop control to realize an equal current distribution. The second part concerns on the system amelioration and efficiency improvement of developed LLC. A special transformer is dimensioned to integrate all magnetic components, and various types of power losses are quantified based on different realization modes and winding geometries to improve its efficiency. This converter also implements a robust synchronous rectification system with phase compensation, a power semiconductor module, and an air-cooling system. The power conversion performance of this prototype is presented and the developed prototype has a peak efficiency of 95% and efficiency is higher than 94% from 500W to 2kW, with a power density of 1W/cm3. The CEM analysis of this converter is also developed in this thesis

APA, Harvard, Vancouver, ISO, and other styles

10

Yan, Ning. "High-frequency Current-transformer Based Auxiliary Power Supply for SiC-based Medium Voltage Converter Systems." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/101507.

Full text

Abstract:

Auxiliary power supply (APS) plays a key role in ensuring the safe operation of the main circuit elements including gate drivers, sensors, controllers, etc. in medium voltage (MV) silicon carbide (SiC)-based converter systems. Such a converter requires APS to have high insulation capability, low common-mode coupling capacitance (Ccm ), and high-power density. Furthermore, considering the lifetime and simplicity of the auxiliary power supply system design in the MV converter, partial discharge (PD) free and multi-load driving ability are the additional two factors that need to be addressed in the design. However, today’s state-of-the-art products have either low power rating or bulky designs, which does not satisfy the demands. To improve the current designs, this thesis presents a 1 MHz isolated APS design using gallium nitride (GaN) devices with MV insulation reinforcement. By adopting LCCL-LC resonant topology, the proposed APS is able to supply multiple loads simultaneously and realize zero voltage switching (ZVS) at any load conditions. Since high reliability under faulty load conditions is also an important feature for APS in MV converter, the secondary side circuit of APS is designed as a regulated stage. To achieve MV insulation (> 20 kV) as well as low Ccm value (< 5 pF), a current-based transformer with a single turn structure using MV insulation wire is designed. Furthermore, by introducing different insulated materials and shielding structures, the APS is capable to achieve different partial discharge inception voltages (PDIV). In this thesis, the transformer design, resonant converter design, and insulation strategies will be detailly explained and verified by experiment results. Overall, this proposed APS is capable to supply multiple loads simultaneously with a maximum power of 120 W for the sending side and 20 W for each receiving side in a compact form factor. ZVS can be realized regardless of load conditions. Based on different insulation materials, two different receiving sides were built. Both of them can achieve a breakdown voltage of over 20 kV. The air-insulated solution can achieve a PDIV of 6 kV with Ccm of 1.2 pF. The silicone-insulated solution can achieve a PDIV of 17 kV with Ccm of 3.9 pF.
M.S.
Recently, 10 kV silicon carbide (SiC) MOSFET receives strong attention for medium voltage applications. Asit can switch at very high speed, e.g. > 50 V/ns, the converter system can operate at higher switching frequency condition with very small switching losses compared to silicon (Si) IGBT [8]. However, the fast dv/dt noise also creates the common mode current via coupling capacitors distributed inside the converter system, thereby introducing lots of electromagnetic interference (EMI) issues. Such issues typically occur within the gate driver power supplies due to the high dv/dt noises across the input and output of the supply. Therefore, the ultra-small coupling capacitor (<5 pF) of a gate driver power supply is strongly desired.[37] To satisfy the APS demands for high power modular converter system, a solution is proposed in this thesis. This work investigates the design of 1 MHz isolated APS using gallium nitride (GaN) devices with medium voltage insulation reinforcement. By increasing switching frequency, the overall converter size could be reduced dramatically. To achieve a low Ccm value and medium voltage insulation of the system, a current-based transformer with a single turn on the sending side is designed. By adopting LCCL-LC resonant topology, a current source is formed as the output of sending side circuity, so it can drive multiple loads importantly with a maximum of 120 W. At the same time, ZVS can use realized with different load conditions. The receiving side is a regulated stage, so the output voltage can be easily adjusted and it can operate in a load fault condition. Different insulation solutions will be introduced and their effect on Ccm will be discussed. To further reduce Ccm, shielding will be introduced. Overall, this proposed APS can achieve a breakdown voltage of over 20 kV and PDIV up to 16.6 kV with Ccm<5 pF. Besides, multi-load driving ability is able to achieve with a maximum of 120 W. ZVS can be realized. In the end, the experiment results will be provided.

APA, Harvard, Vancouver, ISO, and other styles

11

Hu, Boxue. "Challenges and Solutions of Applying Medium-Voltage Silicon Carbide Devices in Medium and High-Voltage Systems." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565967269661455.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Sun, Keyao. "Protection, Control, and Auxiliary Power of Medium-Voltage High-Frequency SiC Devices." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/103743.

Full text

Abstract:

Due to the superior characteristics compared to its silicon (Si) counterpart, the wide bandgap (WBG) semiconductor enables next-generation power electronics systems with higher efficiency and higher power density. With higher blocking voltage available, WBG devices, especially the silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET), have been widely explored in various medium-voltage (MV) applications in both industry and academia. However, due to the high di/dt and high dv/dt during the switching transient, potential overcurrent, overvoltage, and gate failure can greatly reduce the reliability of implementing SiC MOSFETs in an MV system. By utilizing the parasitic inductance between the Kelvin- and the power-source terminal, a short-circuit (SC) and overload (OL) dual-protection scheme is proposed for overcurrent protection. A full design procedure and reliability analysis are given for SC circuit design. A novel OL circuit is proposed to protect OL faults at the gate-driver level. The protection procedure can detect an SC fault within 50 nanoseconds and protect the device within 1.1 microsecond. The proposed method is a simple and effective solution for the potential overcurrent problem of the SiC MOSFET. For SiC MOSFETs in series-connection, the unbalanced voltages can result in system failure due to device breakdown or unbalanced thermal stresses. By injecting current during the turn-off transient, an active dv/dt control method is used for voltage balancing. A 6 kV phase-leg using eight 1.7 kV SiC MOSFETs in series-connection has been tested with voltage balanced accurately. Modeling of the stacked SiC MOSFET with active dv/dt control is also done to summarize the design methodology for an effective and stable system. This method provides a low-loss and compact solution for overvoltage problems when MV SiC MOSFETs are connected in series. Furthermore, a scalable auxiliary power network is proposed to prevent gate failure caused by unstable gate voltage or EMI interference. The two-stage auxiliary power network (APN) architecture includes a wireless power transfer (WPT) converter supplied by a grounded low voltage dc bus, a high step-down-ratio (HSD) converter powered from dc-link capacitors, and a battery-based mini-UPS backup power supply. The auxiliary-power-only pre-charge and discharge circuits are also designed for a 6 kV power electronics building block (PEBB). The proposed architecture provides a general solution of a scalable and reliable auxiliary power network for the SiC-MOSFET-based MV converter. For the WPT converter, a multi-objective optimization on efficiency, EMI mitigation, and high voltage insulation capability have been proposed. Specifically, a series-series-CL topology is proposed for the WPT converter. With the optimization and new topology, a 120 W, 48 V to 48 V WPT converter has been tested to be a reliable part of the auxiliary power network. For the HSD converter, a novel unidirectional voltage-balancing circuit is proposed and connected in an interleaved manner, which provides a fully modular and scalable solution. A ``linear regulator + buck" solution is proposed to be an integrated on-board auxiliary power supply. A 6 kV to 45 V, 100 W converter prototype is built and tested to be another critical part of the auxiliary power network.
Doctor of Philosophy
The wide bandgap semiconductor enables next-generation power electronics systems with higher efficiency and higher power density which will reduce the space, weight, and cost for power supply and conversion systems, especially for renewable energy. However, by pushing the system voltage level higher to medium-voltage of tens of kilovolts, although the system has higher efficiency and simpler control, the reliability drops. This dissertation, therefore, focusing on solving the possible overcurrent, overvoltage, and gate failure issues of the power electronics system that is caused by the high voltage and high electromagnetic interference environment. By utilizing the inductance of the device, a dual-protection method is proposed to prevent the overcurrent problem. The overcurrent fault can be detected within tens of nanoseconds so that the device will not be destroyed because of the huge fault current. When multiple devices are connected in series to hold higher voltage, the voltage sharing between different devices becomes another issue. The proposed modeling and control method for series-connected devices can balance the shared voltage, and make the control system stable so that no overvoltage problem will happen due to the non-evenly distributed voltages. Besides the possible overcurrent and overvoltage problems, losing control of the devices due to the unreliable auxiliary power supply is another issue. This dissertation proposed a scalable auxiliary power network with high efficiency, high immunity to electromagnetic interference, and high reliability. In this network, a wireless power transfer converter is designed to provide enough insulation and isolation capability, while a switched capacitor converter is designed to transfer voltage from several kilovolts to tens of volts. With the proposed overcurrent protection method, voltage sharing control, and reliable auxiliary power network, systems utilizing medium-voltage wide-bandgap semiconductor will have higher reliability to be implemented for different applications.

APA, Harvard, Vancouver, ISO, and other styles

13

Seimbille, Denis. "Design of power supply system in DC electrified transit railways - Influence of the high voltage network." Thesis, KTH, Elektrisk energiomvandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-153924.

Full text

Abstract:

Urban rail systems such as subways and trams transport millions of people every day, oering a high level of service. Most of these systems are fed by direct current (DC). The design of the power supply network of DC electried transit railways is of great importance and requires the use of simulation models. The power supply network is composed of a high voltage network (fed with AC) linked to a traction network (fed with DC) by traction substations. Many simulation models ignore the high voltage network in the design process whereas it has a signicant inuence on the results. A Newton-Raphson algorithm is implemented to solve the AC load ow in the high voltage network, and coupled to the existing simulation software Symphonie. Three dierent high voltage network architectures are simulated, and the simulation results are analyzed. The results show that the voltage drop at the AC side of traction substations and the load sharing between them varies signicantly from one architecture to another. In particular, when several traction substations are connected to the same high voltage loop, voltage drops can be signicant for some traction substations. In conclusion, the design of the power supply network of DC electried transit railways requires the simulation of the high voltage network when several substations are connected to the same high voltage loop.
Publika sparburna transportsystem sasom tunnelbanor och lokalbanor transporterar miljontals manniskor varje dag. De esta korta linjer matas med likstrom. Utformningen av stromforsorjningen till dessa system ar avgorande for ett val fungerande , och forutsatter anvandningen av olika matematiska modeller. Detta natverk bestar av ett vaxelstroms hogspanningsnat som omformas till likstrom i era banmatningsstationer langs banan. Dessa matematiska modeller ignorerar dock ofta hogspanningsdelen i modelleringen, varfor resultatet ibland kan bli missvisande. I detta arbete har en belastningsfordelningsalgoritm baserad pa Newton-Raphsons metod implementerats for att skapa en battre modellering av hsgspanningsdelen i den bentliga programvaran Symphonie. Tre olika hogspanningsstrukturer har bearbetats och resultatet visar att spanningsfall och belastningsf ordelning varierar mellan de olika strukturerna. Speciellt nar era transformatorstationer ar kopplade till samma hogspanningssystem, kan spanningsfall vara patagligt for vissa transformatorstationer. Sammanfattningsvis maste utformningen av hogspanningsystemet till likstromsforsorjda jarnvagar utformas med hjalp av anpassade matematiska modeller som tar hansyn till placering av transformatorstationer liksom hogspanningsnatets kapacitet.

APA, Harvard, Vancouver, ISO, and other styles

14

López, Julià Toni. "Prospects of voltage regulators for next generation computer microprocessors." Doctoral thesis, Universitat Politècnica de Catalunya, 2010. http://hdl.handle.net/10803/77908.

Full text

Abstract:

Synchronous buck converter based multiphase architectures are evaluated to determine whether or not the most widespread voltage regulator topology can meet the power delivery requirements of next generation computer microprocessors. According to the prognostications, the load current will rise to 200A along with the decrease of the supply voltage to 0.5V and staggering tight dynamic and static load line tolerances. In view of these demands, researchers face serious challenges to bring forth compliant solutions that can further offer acceptable conversion efficiencies and minimum mainboard area occupancy. Among the most prominent investigation fronts are those surveying fundamental technology improvements aiming at making power semiconductor devices more effective at high switching frequency. The latter is of critical importance as the increase of the switching frequency is fundamentally recognized as the way forward to enhance power density conversion. Provided that switching losses must be kept low to enable the miniaturization of the filter components, one primary goal is to cope with semiconductor and system integration technologies enabling fast dynamic operation of ultra-low ON resistance power switches. This justifies the main focus of this thesis work, centered around a comprehensive analysis of the MOSFET switching behavior in the synchronous buck converter. The MOSFETs dynamic operation, far from being well describable with the traditional clamped inductive hard-switching mode, is strongly influenced by a number of frequently ignored linear and nonlinear parasitic elements that must be taken into account in order to fully predict real switching waveforms, understand their dynamics, and most importantly, identify and quantify the related mechanisms leading to heat generation. This will be revealed from in-depth investigations of the switched converter under fast switching speeds and heavy load. Recognizing the key relevance of appropriate modeling tools that support this task, the second focal point of the thesis aims at developing a number of suitable models for the switching analysis of power MOSFETs. Combined with a series of design guidelines and optimization procedures, these models form the basis of a proposed methodological approach, where numerical computations replace the usually enormous experimental effort to elucidate the most effective pathways towards reducing power losses. This gives rise to the concept referred to as virtual design loop, which is successfully applied to the development of a new power MOSFET technology offering outstanding dynamic and static performance characteristics. From a system perspective, the limits of the power density conversion will be explored for this and other emerging technologies that promise to open up a new paradigm in power integration capabilities.

APA, Harvard, Vancouver, ISO, and other styles

15

Patel, Prashun R. "An improved method of regulating a high voltage power supply for use in oil well logging applications." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/34072.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Ghasemi, Negareh. "Improving ultrasound excitation systems using a flexible power supply with adjustable voltage and frequency to drive piezoelectric transducers." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/61091/1/Negareh_Ghasemi_Thesis.pdf.

Full text

Abstract:

The ability of a piezoelectric transducer in energy conversion is rapidly expanding in several applications. Some of the industrial applications for which a high power ultrasound transducer can be used are surface cleaning, water treatment, plastic welding and food sterilization. Also, a high power ultrasound transducer plays a great role in biomedical applications such as diagnostic and therapeutic applications. An ultrasound transducer is usually applied to convert electrical energy to mechanical energy and vice versa. In some high power ultrasound system, ultrasound transducers are applied as a transmitter, as a receiver or both. As a transmitter, it converts electrical energy to mechanical energy while a receiver converts mechanical energy to electrical energy as a sensor for control system. Once a piezoelectric transducer is excited by electrical signal, piezoelectric material starts to vibrate and generates ultrasound waves. A portion of the ultrasound waves which passes through the medium will be sensed by the receiver and converted to electrical energy. To drive an ultrasound transducer, an excitation signal should be properly designed otherwise undesired signal (low quality) can deteriorate the performance of the transducer (energy conversion) and increase power consumption in the system. For instance, some portion of generated power may be delivered in unwanted frequency which is not acceptable for some applications especially for biomedical applications. To achieve better performance of the transducer, along with the quality of the excitation signal, the characteristics of the high power ultrasound transducer should be taken into consideration as well. In this regard, several simulation and experimental tests are carried out in this research to model high power ultrasound transducers and systems. During these experiments, high power ultrasound transducers are excited by several excitation signals with different amplitudes and frequencies, using a network analyser, a signal generator, a high power amplifier and a multilevel converter. Also, to analyse the behaviour of the ultrasound system, the voltage ratio of the system is measured in different tests. The voltage across transmitter is measured as an input voltage then divided by the output voltage which is measured across receiver. The results of the transducer characteristics and the ultrasound system behaviour are discussed in chapter 4 and 5 of this thesis. Each piezoelectric transducer has several resonance frequencies in which its impedance has lower magnitude as compared to non-resonance frequencies. Among these resonance frequencies, just at one of those frequencies, the magnitude of the impedance is minimum. This resonance frequency is known as the main resonance frequency of the transducer. To attain higher efficiency and deliver more power to the ultrasound system, the transducer is usually excited at the main resonance frequency. Therefore, it is important to find out this frequency and other resonance frequencies. Hereof, a frequency detection method is proposed in this research which is discussed in chapter 2. An extended electrical model of the ultrasound transducer with multiple resonance frequencies consists of several RLC legs in parallel with a capacitor. Each RLC leg represents one of the resonance frequencies of the ultrasound transducer. At resonance frequency the inductor reactance and capacitor reactance cancel out each other and the resistor of this leg represents power conversion of the system at that frequency. This concept is shown in simulation and test results presented in chapter 4. To excite a high power ultrasound transducer, a high power signal is required. Multilevel converters are usually applied to generate a high power signal but the drawback of this signal is low quality in comparison with a sinusoidal signal. In some applications like ultrasound, it is extensively important to generate a high quality signal. Several control and modulation techniques are introduced in different papers to control the output voltage of the multilevel converters. One of those techniques is harmonic elimination technique. In this technique, switching angles are chosen in such way to reduce harmonic contents in the output side. It is undeniable that increasing the number of the switching angles results in more harmonic reduction. But to have more switching angles, more output voltage levels are required which increase the number of components and cost of the converter. To improve the quality of the output voltage signal with no more components, a new harmonic elimination technique is proposed in this research. Based on this new technique, more variables (DC voltage levels and switching angles) are chosen to eliminate more low order harmonics compared to conventional harmonic elimination techniques. In conventional harmonic elimination method, DC voltage levels are same and only switching angles are calculated to eliminate harmonics. Therefore, the number of eliminated harmonic is limited by the number of switching cycles. In the proposed modulation technique, the switching angles and the DC voltage levels are calculated off-line to eliminate more harmonics. Therefore, the DC voltage levels are not equal and should be regulated. To achieve this aim, a DC/DC converter is applied to adjust the DC link voltages with several capacitors. The effect of the new harmonic elimination technique on the output quality of several single phase multilevel converters is explained in chapter 3 and 6 of this thesis. According to the electrical model of high power ultrasound transducer, this device can be modelled as parallel combinations of RLC legs with a main capacitor. The impedance diagram of the transducer in frequency domain shows it has capacitive characteristics in almost all frequencies. Therefore, using a voltage source converter to drive a high power ultrasound transducer can create significant leakage current through the transducer. It happens due to significant voltage stress (dv/dt) across the transducer. To remedy this problem, LC filters are applied in some applications. For some applications such as ultrasound, using a LC filter can deteriorate the performance of the transducer by changing its characteristics and displacing the resonance frequency of the transducer. For such a case a current source converter could be a suitable choice to overcome this problem. In this regard, a current source converter is implemented and applied to excite the high power ultrasound transducer. To control the output current and voltage, a hysteresis control and unipolar modulation are used respectively. The results of this test are explained in chapter 7.

APA, Harvard, Vancouver, ISO, and other styles

17

Boora, Arash Abbasalizadeh. "Flexible high-power multi DC-DC converters for train systems." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/33208/1/Arash_Boora_Thesis.pdf.

Full text

Abstract:

This thesis reports on the investigations, simulations and analyses of novel power electronics topologies and control strategies. The research is financed by an Australian Research Council (ARC) Linkage (07-09) grant. Therefore, in addition to developing original research and contributing to the available knowledge of power electronics, it also contributes to the design of a DC-DC converter for specific application to the auxiliary power supply in electric trains. Specifically, in this regard, it contributes to the design of a 7.5 kW DC-DC converter for the industrial partner (Schaffler and Associates Ltd) who supported this project. As the thesis is formatted as a ‘thesis by publication’, the contents are organized around published papers. The research has resulted in eleven papers, including seven peer reviewed and published conference papers, one published journal paper, two journal papers accepted for publication and one submitted journal paper (provisionally accepted subject to few changes). In this research, several novel DC-DC converter topologies are introduced, analysed, and tested. The similarity of all of the topologies devised lies in their ‘current circulating’ switching state, which allows them to store some energy in the inductor, as extra inductor current. The stored energy may be applied to enhance the performance of the converter in the occurrence of load current or input voltage disturbances. In addition, when there is an alternating load current, the ability to store energy allows the converter to perform satisfactorily despite frequently and highly varying load current. In this research, the capability of current storage has been utilised to design topologies for specific applications, and the enhancement of the performance of the considered applications has been illustrated. The simplest DC-DC converter topology, which has a ‘current circulating’ switching state, is the Positive Buck-Boost (PBB) converter (also known as the non-inverting Buck-Boost converter). Usually, the topology of the PBB converter is operating as a Buck or a Boost converter in applications with widely varying input voltage or output reference voltage. For example, in electric railways (the application of our industrial partner), the overhead line voltage alternates from 1000VDC to 500VDC and the required regulated voltage is 600VDC. In the course of this research, our industrial partner (Schaffler and Associates Ltd) industrialized a PBB converter–the ‘Mudo converter’–operating at 7.5 kW. Programming the onboard DSP and testing the PBB converter in experimental and nominal power and voltage was part of this research program. In the earlier stages of this research, the advantages and drawbacks of utilization of the ‘current circulating’ switching state in the positive Buck-Boost converter were investigated. In brief, the advantages were found to be robustness against input voltage and current load disturbances, and the drawback was extra conduction and switching loss. Although the robustness against disturbances is desirable for many applications, the price of energy loss must be minimized to attract attention to the utilization of the PBB converter. In further stages of this research, two novel control strategies for different applications were devised to minimise the extra energy loss while the advantages of the positive Buck-Boost converter were fully utilized. The first strategy is Smart Load Controller (SLC) for applications with pre-knowledge or predictability of input voltage and/or load current disturbances. A convenient example of these applications is electric/hybrid cars where a master controller commands all changes in loads and voltage sources. Therefore, the master controller has a pre-knowledge of the load and input voltage disturbances so it can apply the SLC strategy to utilize robustness of the PBB converter. Another strategy aiming to minimise energy loss and maximise the robustness in the face of disturbance is developed to cover applications with unexpected disturbances. This strategy is named Dynamic Hysteresis Band (DHB), and is used to manipulate the hysteresis band height after occurrence of disturbance to reduce dynamics of the output voltage. When no disturbance has occurred, the PBB converter works with minimum inductor current and minimum energy loss. New topologies based on the PBB converter have been introduced to address input voltage disturbances for different onboard applications. The research shows that the performance of applications of symmetrical/asymmetrical multi-level diode-clamped inverters, DC-networks, and linear-assisted RF amplifiers may be enhanced by the utilization of topologies based on the PBB converter. Multi-level diode-clamped inverters have the problem of DC-link voltage balancing when the power factor of their load closes to unity. This research has shown that this problem may be solved with a suitable multi-output DC-DC converter supplying DClink capacitors. Furthermore, the multi-level diode-clamped inverters supplied with asymmetrical DC-link voltages may improve the quality of load voltage and reduce the level of Electromagnetic Interference (EMI). Mathematical analyses and experiments on supplying symmetrical and asymmetrical multi-level inverters by specifically designed multi-output DC-DC converters have been reported in two journal papers. Another application in which the system performance can be improved by utilization of the ‘current circulating’ switching state is linear-assisted RF amplifiers in communicational receivers. The concept of ‘linear-assisted’ is to divide the signal into two frequency domains: low frequency, which should be amplified by a switching circuit; and the high frequency domain, which should be amplified by a linear amplifier. The objective is to minimize the overall power loss. This research suggests using the current storage capacity of a PBB based converter to increase its bandwidth, and to increase the domain of the switching converter. The PBB converter addresses the industrial demand for a DC-DC converter for the application of auxiliary power supply of a typical electric train. However, after testing the industrial prototype of the PBB converter, there were some voltage and current spikes because of switching. To attenuate this problem without significantly increasing the switching loss, the idea of Active Gate Signalling (AGS) is presented. AGS suggests a smart gate driver that selectively controls the switching process to reduce voltage/current spikes, without unacceptable reduction in the efficiency of switching.

APA, Harvard, Vancouver, ISO, and other styles

18

Циганчук, Т. Г., and А. В. Булашенко. "Усунення генерації в іоністорних джерелах живлення." Thesis, Сумський державний університет, 2018. http://essuir.sumdu.edu.ua/handle/123456789/67630.

Full text

Abstract:

Мікросхеми керування зарядом та разрядом іоністорів виробляються декількома ведучими виробниками. За рахнок того, що напруга на цих конденсаторах змінюється за рахунок їх заряда та разряда, звичайно виробники вмикають у склад таких мікросхем DC/DC перетворювачі, перетворюючі змінну напругу в стабільну, що підходить для живлення іншої системи. Ці мікросхеми, що випускають, продовжують підтримувати стабільну напругу живлення до тих пір, доки напруга на іоністорі не зменшиться до визначеного рівня. Однако коли напруга доходить до цього рівня, стандартні мікросхеми починають вести себе неадекватно.

APA, Harvard, Vancouver, ISO, and other styles

19

Gábel, Marián. "Spínaný stejnosměrný laboratorní zdroj 30V 60A." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442786.

Full text

Abstract:

The master thesis deals with design of a switched DC power supply with output parameters of 30 V 60 A. The power supply uses the connection of two single switch forward converters with opposite phase. The topology was chosen based on a comparison of specific schematics in the first part. The body of the thesis is covered in chapter which deals with design and analysis of power circuits of the converter. The chapter describes detailed design of pulse transformers, dimensioning of semiconductors and cooling system of the converter. For lower power losses, the system of synchronous rectifying is chosen at the output of the circuit. The regulation of the output is based on cascade structure with a superior voltage and dependent current loop. Appropriate over current protection is provided by sensing the output current and using current transformers for primary current measure.

APA, Harvard, Vancouver, ISO, and other styles

20

Gutierrez, Saenz Juan. "Energy analysis and cost estimation of a potential On-shore Power Supply system in the Port of Gävle." Thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-30378.

Full text

Abstract:

The Port of Gävle is one of the most important harbours in Sweden as far as size and freight capacity is concerned. Marine traffic is increasing greatly, thus environmental pollution as well as noise and vibrations are of major concern in port cities. Shore to ship power supply systems might be a feasible solution to curtail emissions because the Auxiliary Engines are instead shut down while the ship stays alongside the quay. The literature review shows they are reliable and very appealing in all respects, thereby contributing to sustainable development. Taking into account the kind of vessels that call at the Port of Gävle, a High Voltage Shore Connection is recommendable, in compliance with the International Standards. An own technical survey is developed to gather all the information, as well as personal interviews to collect first-hand data. Technical issues such as the synchronisation procedure and the ground system with regard to safety are briefly discussed. Due to the lack of data, calculations consist of average values: peak and average demand, and fuel consumption during a typical call. Considering updated energy prices for both electricity and fuel, results show that an on‑shore power supply system make energy costs decrease by 71% at berth in comparison with burning marine fuel, which is saved by around 4 tonnes per call. Additionally, up to 5126 tonnes of CO2 are avoided per year, among other pollutants. Shore‑side power has proven to be profitable and appealing to the Port of Gävle; however, vessels need to be retrofitted, which implies relatively high investments. Collaboration agreements and shipping companies’ willingness to undergo changes are key issues that still need to be solved.

APA, Harvard, Vancouver, ISO, and other styles

21

Tejmlová, Lenka. "Laboratorní zdroj s vysokou účinností." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219100.

Full text

Abstract:

The project shows the problems of power supply in electrical engineering. It describes the general parameters of these types of supplies and presents their characteristics. Based on these findings, it is also focused on the selection of specific elements of the laboratory supply, to reach the given parameters. It contains the recalculations of the parameters of other additional components. The overall scheme of the supply is divided into several blocks, thematically corresponded to subchapters. According to the accomplished concept the laboratory supply is realized and its parameters had been tested. Projects results are assessed at the end.

APA, Harvard, Vancouver, ISO, and other styles

22

Zemánek, Miroslav. "Užití výkonových měničů ve zdrojích vysokého napětí." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-233463.

Full text

Abstract:

This work is concerned with power inverters for alternate high voltage power sources. The theoretical part describes the topology of inverters that can be used in alternate power sources. A model of voltage transformer is described in details to better understand the parasitic effects that are inevitably present in high voltage power sources and, therefore, have to be taken into consideration at the design of high voltage power sources. The work is oriented to problems of alternate high voltage power sources for ozone generators. This is the reason, why the theoretical and, partially, also the experimental part deal with the properties of ozone and its use. The experimental part solves high voltage inverter with capacitive load that is formed by discharge element of an ozone generator. Designed inverter is able to feed the capacitive load with high voltage at very short periods of time from several microseconds up to tens of nanoseconds. In comparison with the length of voltage pulses in common ozone generators, this pulses are more than 100-time shorter. This has a positive effect to silent discharge characteristics.

APA, Harvard, Vancouver, ISO, and other styles

23

Pocius, Lukas. "Aukštosios įtampos programuojamo šaltinio sukūrimas ir jo parametrų tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110615_175842-20769.

Full text

Abstract:

Baigiamajame darbe suprojektuotas ir ištirtas programuojamas aukštosios įtampos maitinimo šaltinis. Įvade išnagrinėti programuojami aukštosios įtampos maitinimo šaltiniai, jų taikymo ir panaudojimo sritys. Taip pat išnagrinėti GPIB sąsajos privalumai ir trūkumai. Analitinėje dalyje smulkiai nagrinėjama maitinimo šaltinių sandara ir veikimo principas. Pateikiamos kai kurių maitinimo šaltinio sandaros elementų grandinių schemos. Taip pat analitinėje dalyje smulkiai išnagrinėtas GPIB sąsajos veikimo principas ir šios sąsajos taikymo galimybės. Projektinėje dalyje ištirtas aukštosios įtampos maitinimo šaltinis ir jo charakteristikos, pateikta išėjimo signalo įtampos forma. Taip pat šioje dalyje suprojektuota GPIB sąsaja maitinimo šaltiniui ir pateiktas programinės įrangos algoritmas. Darbą sudaro 6 dalys: įvadas, analitinė dalis, projektinė dalis, išvados ir pasiūlymai, literatūros sąrašas. Darbo apimtis: 57 p. teksto be priedų, 56 pav., 4 lent., 32 bibliografiniai šaltiniai.
In this final project we made research of high voltage programmable power supply. In the preface of this project the high voltage power supplies, there application and using areas are described. Also in this part of the work we describe GPIB interface advantages and disadvantages. In the analytic part we analyze power supply structure and working principles in detail. We give some power supplies structure elements schemes. Also in this part of work we analyze GPIB interface working principle and applying possibilities in detail. In the design part of the work we made a research of high voltage power supply, its characteristics and we give outgoing signal form in pictures. Also in this part we design GPIB interface for high voltage power supply and algorithm of software. Structure: introduction, analytical part, design part, conclusions and suggestions, references.

APA, Harvard, Vancouver, ISO, and other styles

24

Ptáček, Karel. "Vysokonapěťové struktury pro galvanickou iziolaci v integrovaných obvodech." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-417477.

Full text

Abstract:

Tato dizertační práce představuje novou techniku laterární rezonanční vazby, která je využita v návrhu galvanicky izolovaného posouvače úrovně, který je následně implementován v 800 V půlmůstkovém kontroléru pro průmyslové aplikace. Ve srovnání s tradičními galvanickými izolátory jsou výrobní náklady tohoto řešení nižší. Pro aplikace vyžadující vyšší úroveň galvanické izolace je popsán následný vývoj galvanicky izolovaného posouvače úrovně, který využívá pouze jeden galvanicky oddělený posouvač úrovní pro komunikaci v obou směrech, což výrazně snižuje plochu struktury izolátoru. Jako součást následného návrhu je představen galvanický izolátor který je schopen přenášet analogovou hodnotu napětí. Analogový izolátor byl testován v reálné aplikaci síťového spínaného zdroje jako náhrada standardního optočlenu. Tato konstrukce umožňuje integraci primárních a sekundárních obvodů v jednom pouzdře, což umožní snížit složitost a cenu spínaného zdroje.

APA, Harvard, Vancouver, ISO, and other styles

25

Saint-Laurent, Martin. "Modeling and Analysis of High-Frequency Microprocessor Clocking Networks." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7271.

Full text

Abstract:

Integrated systems with billions of transistors on a single chip are a now reality. These systems include multi-core microprocessors and are built today using deca-nanometer devices organized into synchronous digital circuits. The movement of data within such systems is regulated by a set of predictable timing signals, called clocks, which must be distributed to a large number of sequential elements. Collectively, these clocks have a significant impact on the frequency of operation and, consequently, on the performance of the systems. The clocks are also responsible for a large fraction of the power consumed by these systems. The objective of this dissertation is to better understand clock distribution in order to identify opportunities and strategies for improvement by analyzing the conditions under which the optimal tradeoff between power and performance can be achieved, by modeling the constraints associated with local and global clocking, by evaluating the impact of noise, and by investigating promising new design strategies for future integrated systems.

APA, Harvard, Vancouver, ISO, and other styles

26

Ghossein, Layal. "Alimentation de circuit de commande rapprochée « Gate-drive » pour nouveaux convertisseurs de puissance haute tension." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI016.

Full text

Abstract:

Le transport d’énergie par des lignes HVDC constitue le principal réseau de transmission d’énergie électrique du futur. Les convertisseurs de puissance (par exemple de type MMC) qui constitueront ce réseau devront être capables de gérer des tensions de l’ordre de centaines de kilovolts ce qui rend critique l’alimentation des dispositifs de contrôle (gate-drive) de ces convertisseurs. Il est nécessaire de concevoir des solutions qui garantissent l’alimentation de ces gate-drives avec une isolation.Pour ce faire, un circuit basé sur le principe du flyback et utilisant un JFET normalement passant a été développé. Il est placé en parallèle d’un condensateur typiquement connecté aux bornes d’un bras d’onduleur. Il permet d’alimenter le dispositif de puissance dès qu’une faible tension est appliquée à son entrée. Cette fonction est assurée grâce au caractère normalement passant du JFET. Pour le prototype développé, la tension du bras est de 2 kV. La tension de sortie est régulée à 24 V. De nos jours, des JFET normalement passants avec une tenue en tension supérieure à 2 kV n’existent pas sur le marché. Donc, pour supporter les tensions mises en jeu dans le circuit, une mise en série de JFET SiC normalement passants commandés par un MOSFET Si a été réalisée (montage « super-cascode »). Le circuit développé est capable de fournir 20 W pour alimenter des gate-drives à des potentiels flottants. Le rendement obtenu est proche de 60 %. Aussi, le problème d’isolation est résolu par cette solution d’auto-alimentation
HVDC power transmission is the future of the electrical energy transmission network. The power converters (e.g. MMC) used in this network will be able to cope with voltages of hundreds of kV, making the power supply of the gate-drive devices in these converters challenging. It is then necessary to design solutions that guarantee the power supply of these gate-drives, while providing high voltage isolation. To do this, a circuit, based on the flyback principle, was developed. It is placed in parallel with a capacitor typically connected to a half-bridge circuit. It has an auto-start feature. This allows to supply the gate-drive as soon as a low voltage is applied to the input of the self-supply system. This is obtained by taking advantage of the normally-ON character of the JFET. In our prototype, the input voltage is 2 kV. High voltage JFETs of 2 kV and higher breakdown voltages are not yet available on the market. So, to achieve this high voltage capacity, a series of Normally-ON SiC JFETs controlled by a low voltage Si MOSFET (Super-cascode circuit) is used in the circuit. The developed circuit is able to supply 20 W at different floating potentials with output voltage regulated at 24 V and an efficiency close to 60%. The isolation problem is then solved using this solution

APA, Harvard, Vancouver, ISO, and other styles

27

Uherek, Jaromír. "Návrh vysokonapěťového zdroje sinusového napětí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220114.

Full text

Abstract:

Object of the master´s thesis is design of a high voltage power supply for testing insulation materials with output voltage 50 V - 2 kV at fixed frequency 50 Hz. The power supply is controlled by personal computer and measured data are sent back to the personal computer. The Universal Serial Bus (USB) is used for communication between the PC and the device.

APA, Harvard, Vancouver, ISO, and other styles

28

Španěl, Petr. "Spínané zdroje." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-433024.

Full text

Abstract:

This thesis deals with switched mode power supplies based on resonant principle to achieve high efficiency. Several ways of switched mode power supplies optimalisation are described as part of the work to achieve better efficiency. Priparily, the new generation of switching elements based on SiC and resonant topology are used to achieve significant switching loss minimization. The selected resonant topology is simualted in detail and then built with focus on high efficiency. The main content of the work consists in the design and realization of the switched mode power supply with selected control algorithms and their comparison. The problems associated with usage of new SiC MOSFET generation in TO-247-4L package are being solved within the design and implementation of the power source. To solve the main problems, new 3rd SiC MOSFET gate driver was developer for working with switching frequencies in hundreds of kHz and resisting very high voltage stress on the controlled transistor. The next part of the gate driver is the overcurrent protection. The overcurrent limit can be set easily by changing one component. This protection reacts very quickly in hundreds of nanoseconds, so it is capable of saving the converter even in branch failure and going to hard short circuit. The functional sample of the series resonant converter was built and revated in the work. The converter based on 3. Generation of SiC MOSFET transistors from Cree in a modern case TO-247-4L was built. For this inverter, it was also necessary to develop both the control scheme and the resonance frequency tracking to achieve accurate switching and thus achieve the use of the resonant principle of the converter to the maximum extent possible. The result of this work is up to 3 kW converter with adjustable output voltage while maintaining high efficiency up to 96%.

APA, Harvard, Vancouver, ISO, and other styles

29

LAVIOLA, MICHELE. "LNG as the future marine fuel, Waste Heat Recovery Systems & Cold Ironing solutions for eco-friendly maritime transport." Doctoral thesis, Università degli studi di Genova, 2018. http://hdl.handle.net/11567/930196.

Full text

Abstract:

Nowadays a regulatory framework regarding the pollutant emissions abatement, both at international and local level, significantly interests the maritime sector. To comply with the latest environmental rules, a new approach to ship design and a renewed way to operate the ship are need both in navigation and in harbour. This PhD Thesis aims to investigate on the positive features offered by the LNG fuel, more eco-friendly than the traditional marine fuel oils. In the first part of the research, the performance comparison between two marine engines, fuelled by natural gas and diesel oil respectively is reported. Two different simulation codes, one for each engine, validated by means of geometrical and performance data provided by the manufacturer have been developed to extend the comparison to the whole working area of the examined engines. In the second part of the research, a LNG-repowering study of a cruise ferry is presented. The study is enhanced by the investigation on possible Waste Heat Recovery (WHR) systems aiming at the reduction of Green House Gas (GHG), pollution, and money saving. A computational code has been developed to carry out the sizing and to analyse the energetic performance and economical aspects of the several examined WHR layout systems. The more eco-friendly layout for the considered ship is proposed to comply with in force rules. The third part of the PhD Thesis is focused on studying some maritime technical solutions for the electric energy generation and delivery to ships moored in port, by means of LNG fuelled generators installed on board a floating unit. Two different scenarios, regarding the LNG supply chain, are considered and some options for producing cleaner electric energy are then investigated. The reference area examined in this study is the old port of Genoa, where the traffic of both passenger and cargo ships takes place. The analysis is carried out by means of a MATLAB numerical code to calculate the most important features of the floating unit, as dimensions and weights and the most significant characteristics of the electric generation equipment, as the average load factor, fuel consumption and energy cost. From an economical point of view, the externalities costs abatement, thanks to the technical solution proposed are investigated. The study also focuses on the estimation of governmental incentives to promote and sustain the use of the proposed power supply barge, resulting into a fully positive technical solution.

APA, Harvard, Vancouver, ISO, and other styles

30

Joshi, T. G. Subhash. "Power Electronic Technologies for Medium and High Power High Voltage Power Supplies." Thesis, 2017. http://etd.iisc.ac.in/handle/2005/4322.

Full text

Abstract:

The performance of systems used in various high voltage applications depend majorly on the output voltage ripple of High Voltage Power Supplies (HVPS). One of the failure mode of microwave tube (MWT) commonly used in these applications is due to the energy accumulation above the specified limit during fault events due to higher stored energy in HVPS. This demands either a protection for MWT or reduced ripple voltage without increasing the stored energy. This thesis investigates a protection device for MWT that operate with MW power level HVPS, and design method to reduce the output voltage ripple for medium power HVPS. A crowbar is an energy diverting device connected in parallel with the MWT. It protects the tube during fault by providing an alternative path for the ow of energy. Conventional crowbars are built using either mercury or nitrogen gas-based switches. Due to the environmental concern and higher operational cost, the state-of-the-art is to replace these devices with semiconductor devices, referred to as solid state crowbar (SSC). This research, models and designs the subcomponents of an SSC, including: (i) Modelling of fault current, and a fuse wire that is used to emulate a MWT during internal arc (ii) Design of di=dt limiting inductor (iii) Design of static and dynamic voltage balancing network for the thyristor (iv) Mechanical assembly design that ensures meeting the required crowbar electrical characteristics (v) Selection of cost-effective semiconductor device for crowbar application (vi) Thermal modelling of crowbar for pulse power applications (vii) Selection of cable for the pulse power application. In a switched converter topology, the causes of output voltage ripple are: the switch action, input dc ripple, and variations in the load. In this thesis the influence of input voltage ripple on the output dc voltage, called Audio Susceptibility (AS), is discussed. AS of load resonant converters has not been widely studied in literature. This research uses exact discretization method to obtain: (i) The analytical large signal and cyclic steady state model of the Series Resonant Converter (SRC) considering the resonant tank and output filter states (ii) The analytical small signal AS model of the SRC, and resonant gain condition for input ripple (iii) The design of an SRC for superior AS performance (iv) A comparison of SRC design for (a) superior AS performance and (b) maximum power transfer capability (v) A selection of SRC components including the high voltage high frequency magnetics and selection of the MosFET. All the modelling and design method considered in this work has been verified by experimental studies on two 10MW, 10kV peak power SSC and a 10kW, 10kV SRC that has been fabricated as a part of the research.

APA, Harvard, Vancouver, ISO, and other styles

31

Hung-WenChen and 陳鴻文. "Analysis and Implementation of High Voltage Power Supply." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/83599253900072512509.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Li, Ren-Hao, and 李仁豪. "Modular Design of Adjustable High Voltage Pulsed Power Supply." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8u46ys.

Full text

Abstract:

碩士
國立臺灣科技大學
電機工程系
107
This thesis aims to achieve a modular design of an adjustable high voltage pulsed power supply. The proposed system includes a DC/DC converter and a circuit for controlling output pulse width. The DC/DC converter is structured by full-bridge LLC resonant circuit as a basic power module and combines through input parallel output series (IPOS) form to increase the output voltage and output power. Moreover, the digital controller is incorporated with a human-machine interface, where the different output specifications can be obtained according to the preset parameter values. In addition, in order to stabilize output voltage, the frequency modulation technique is used to reach the required level, and the duty cycle control is employed to balance the output voltage between power modules. Furthermore, the burst mode is added into the pulse width control strategy for eliminating voltage spike and resonant current spike. Finally, both the computer simulation and experimental results are used to verify the feasibility and validity of the proposed system.

APA, Harvard, Vancouver, ISO, and other styles

33

Ke, Chih Wei, and 柯智偉. "Development of a High-Frequency High-Voltage Pulse Power Supply System." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/03556125194806504443.

Full text

Abstract:

碩士
南台科技大學
電機工程系
97
This thesis discusses control methods of high-frequency high-voltage pulse power supply system. It can be applied to the dielectric barrier discharging, corona discharging, and so on. The proposed structure’s first stage is active power factor corrector, It is provides steady DC voltage by boost AC-DC conveter to second stage’s full-bridge ZVS converter to get the desired voltage. The second stage is controlled by pulse width modulation and pulse density modulation, As the pulse width modulation can’t control the system in low power, range a pulse density modulation control is propose to improve. This thesis used the Microchip controller to achieve the pulse density modulation control, thus the high-frequency high-voltage pulse power supply system can have both the pulse width modulation control and pulse density modulation control functions.

APA, Harvard, Vancouver, ISO, and other styles

34

Kuo-YiHsiao and 蕭國毅. "Design and Implementation of a High-Voltage Power Supply with Power Factor Correction." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/36246230702646579554.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

K, Aroul. "Development of efficient power supply For low voltage high current Applications." Thesis, 2009. http://ethesis.nitrkl.ac.in/2760/1/mtech_research_Thesis.pdf.

Full text

Abstract:

In order to meet demands for faster and more efficient data processing, modern microprocessors are being designed with lower voltage implementations. The continuous packing of more devices on a single processor chip is increasing its current demands calling for an aggressive power management. These demands, in turn require special power supplies to provide lower voltages with higher currents capabilities for microprocessors. This work presents a modified low voltage high current Voltage Regulator Module (VRM) technology for desktop computers, and portable applications. The developed advanced VRM has advantages over conventional ones in power efficiency and reliability. The SMPS outputs of desktop computers are mainly􀵇5􀜸,􀵇12􀜸. Considering the factor of distribution loss for today’s processors +12V input supply is used instead of +5V and then it is step down to 1.2V. To make this dc/dc conversion efficient at lower voltages, synchronous converter is an obvious choice because of lower conduction loss in the diode. Primarily the various losses occurring in Synchronous Buck Converter (SBC) is analyzed mathematically. The results conclude the dominance of the switching loss on the high side MOSFET. ZVT, the most efficient among the soft switching techniques is employed to the SBC. The suggested Zero Voltage Transition (ZVT) Single Phase SBC is simulated using PSIM for design values of 3.3V, 12A output and switching frequency 200 kHz. The proposed converter exhibits an efficient performance in comparison with the conventional converter. Additionally, the resonant auxiliary circuit in ZVT, which conducts for a short period of time, is also devoid of the switching loss. The simulation results are then verified experimentally by developing a prototype of the proposed converter for a switching frequency of 200 kHz.

APA, Harvard, Vancouver, ISO, and other styles

36

Zeng, You-Wei, and 曾宥瑋. "Study and Implementation of a High-Voltage DC Power Supply for Wide-Range Output Voltage." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/51874345130158260233.

Full text

Abstract:

碩士
國立臺灣科技大學
電子工程系
103
This thesis mainly develops a high-voltage DC power supply with a wide-range of adjustable output voltage. It focuses on the design and control of a full-bridge phase-shifted series resonant converter. The proposed full-bridge phase-shift series resonant converter features a novel two-mode operation. When low voltage output, it operates in phase-shifted PWM mode. When high voltage output, it operates in series resonant mode. In both modes, the zero voltage switching can be achieved during dead times. Therefore, the proposed converter can realize the target of high conversion efficiency for all voltage conditions. The power-stage is a full-bridge phase-shifted series resonant converter, which has the characteristics of zero voltage switching. Since the output apply in high-pressure situations, so the secondary side choose a full bridge rectifier circuit to reduce the voltage stress. In order to implement the digital controller, the DSP chip TMS320F28035 developed by Texas Instruments is adopted. Finally, a 450W adjustable power supply with 400V input voltage and an output voltage ranging from 400V to 3000V is designed and implemented. Experimental results of the prototype converter are shown and discussed to verify the feasibility of the studied scheme.

APA, Harvard, Vancouver, ISO, and other styles

37

Chia-LunLiu and 劉加侖. "Study and Implementation of High Voltage Power Supply for X-ray Generator." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/31444008637560923764.

Full text

Abstract:

碩士
國立成功大學
電機工程學系碩博士班
98
In this thesis, a high voltage power supply for X-ray generator is studied and implemented. X-ray power supply is composed of high voltage power supply and filament circuit. The high voltage power supply consists of a full-bridge converter, a series resonant tank, a high step-up transformer and a voltage multiplier, which utilizes phase-shift control scheme to control the power supply for achieving high voltage output. The filament circuit employs push-pull topology to generate preheated power. When the filament is preheated and the high voltage output terminal is crossed on X-ray’s anode and cathode, the X-ray tubes is derived. Finally, a laboratory full-bridge prototype of 50-100 kV with adjustable voltage output and a push-pull circuit for the filament circuit of output voltage 3-5 V has been implemented to verify the theoretical analysis. Keywords：X-ray generator, full-bridge phase-shifted, voltage multiplier, filament preheater, high-voltage power supply

APA, Harvard, Vancouver, ISO, and other styles

38

Hsu, Ming Shyang, and 許明祥. "Implementation of High Voltage Power Supply Applied to the Traveling Wave Tube." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/94452542343522285244.

Full text

Abstract:

碩士
輔仁大學
電子工程學系
92
A high voltage power supply applied to the traveling wave tube (TWT) is proposed in this paper. A Buck current-fed full bridge converter is used to reduce the effect of leakage inductances of high voltage transformer for improving the performance. The switching frequency of the converter is chosen at 100 kHz to reduce the size and weight of power supply. The transformer windings utilize 19 kV insulation wire. The high voltage output rectifier and double voltage multiplier provided the need for multiple high voltage outputs for cathode, collector-1, collector-2 of the TWT, respectively. This paper mentioned the simply scheme to develop and design the high voltage power supply. Finally, computer simulation and experimental results of laboratory prototype with 100 kHz、10 kV and 1 kW output are presented to demonstrate the feasibility of circuit topology.

APA, Harvard, Vancouver, ISO, and other styles

39

Chen, Cun-Min, and 陳存旻. "An Adjustable Pulse-width High Voltage Pulsed Power Supply with Digital Controller." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/pw3u87.

Full text

Abstract:

碩士
國立臺灣科技大學
電機工程系
106
This thesis presents an adjustable pulse-width high voltage pulsed power supply based on the full-bridge LLC resonant topology with a digital controller. First, the system transfer function including parastic capacitance effect is derived to select the resonant component. Moreover, the proposed system can achieve zero voltage switching to reduce power loss even under pulsed output. In addition, the modified burst PWM control is combined with variable frequency control to eliminate the output voltage spike. Furthermore, the voltage feedback control is implemented by using the auxiliary winding to simplify the circuit design and to provide electrical isolation. Finally, both the computer simulation and experimental results are used to verify the feasibility and validity of the proposed system.

APA, Harvard, Vancouver, ISO, and other styles

40

Chang, De-Wei, and 張德威. "Study and Implementation of a DC Power Supply for High-Voltage Capacitor Testing." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/85397133952837459143.

Full text

Abstract:

碩士
國立臺灣科技大學
電子工程系
104
This thesis mainly develops a high-voltage DC power supply with wide-range output voltage for high voltage capacitor test. The power stage consists of a buck DC-DC converter and a full-bridge SRC DC-DC converter. The pre-stage buck converter is operated to achieve the proposed voltage adjustment and provide the input voltage for post-stage converter. The post-stage circuit is a full-bridge phase-shifted series resonant converter, which provides 1kW rated power and a wide-range output voltage from 40V to 6kV. A DSP chip TMS320F28035 developed by Texas Instruments is adopted for realizing digital controller. In this thesis, the operation principles and design considerations for a prototype system were analyzed and discussed. Experimental results of the prototype converter are shown to verify the feasibility of the studied scheme.

APA, Harvard, Vancouver, ISO, and other styles

41

Yang, Min-Nan, and 楊敏男. "Effects and Improvements of Voltage Sags on High-Tech Industry Power Supply System." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/28410460109047005899.

Full text

Abstract:

碩士
國立彰化師範大學
電機工程學系
99
Due to rapid development in the Central Taiwan Science Park (CTSP) of Taiwan, the requirements of electricity consumption grow fast year by year. The high-tech industry has the characteristics of highly sensitive production equipment and intensive production, and thus has great requirements of stable power supply and good power quality. This study is of a high-tech factory in the CTSP as an example, by building power quality monitoring systems, and thus based on the SEMI F47 standard to analyze the reasons and categories of the voltage sags. The results can be as a reference for installing voltage sag improvement equipment and new high-tech factory and power system planning. Further, installing the voltage sag compensation equipment to improve the loss due to voltage sag is illustrated. In addition, the analysis and comparison of the voltage sag events before and after the establishment of the EHV substation (E/S) in the CTSP show the benefits of the E/S on reducing the voltage sag occurrences and the losses of the production.

APA, Harvard, Vancouver, ISO, and other styles

42

Chu, Hsin-Yu, and 朱星諭. "A STUDY OF OUTPUT ADJUSTABLE SWITCHING-MODE HIGH POWER DC POWER SUPPLY WITH HIGH EFFICIENCY AND LOW VOLTAGE REGULATION." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/57531397563916727568.

Full text

Abstract:

碩士
大同大學
電機工程研究所
89
The purpose of this thesis is to develop a high output power, adjustable switching-mode DC power supply with high efficiency, low ripple factor, and low voltage regulation. The system consists of a 3φ AC controller, a 3φisolating transformer, and DC output active compensating filters. The 3φ switching-mode AC controller with PWM control takes charge of the variable output voltage. A 3φ transformer used for isolating the load and source, and filtering out high frequency harmonics by its inductance effect. The DC output active compensating filter takes charges of compensating and reducing the low frequency ripple voltage that is hard filtered by classical passive LC filter. Finally a single-chip microprocessor 80196MC, with proper software is used to implement the control scheme of the system and accomplish the expectation of the low voltage regulation. In the thesis, the designs of hardware structure and software algorithm are established, the proposed switching-mode DC power supply may operate at 15KW and 0V∼130V adjustable output voltage, the efficiency is greater than 90%, voltage regulation and ripple factor are both less than 1.0%.

APA, Harvard, Vancouver, ISO, and other styles

43

Chuang, Ching-Fang, and 莊景芳. "Application of High Voltage and High Frequency Power Supply for the Traveling Wave Tube Circuit System." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/82473277714267789922.

Full text

Abstract:

碩士
輔仁大學
電子工程學系
89
ABSTRACT The traveling wave tube is a device that can change the RF signal strength and frequency modification by input control signal. It is widely used in the list of electric application strategies as below: Doppler radar system, electronic counter-measurement system, guide missile system, the satellite communication system, television translating system, the low noise amplifier receiver, high band radar system, the wave source of dot matrix in phase, …and so on. The merit is it only needs the stable input power equipment with the guarantee to work fine. Again, because of the different operating frequency and output power in different working place, the current solutions can’t meet its need. The contribution of this thesis is the buck current-fed full bridge power converter because the better adapting. It is in designing and manufacture of the topology. It is approved by the quality and reliability.

APA, Harvard, Vancouver, ISO, and other styles

44

Liu, Wei-Chang, and 劉偉章. "The Design of Very-Low-Voltage Operational Amplifier with High Power Supply Rejection Ratio." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/01331873055627426172.

Full text

Abstract:

碩士
國立雲林科技大學
電子與資訊工程研究所碩士班
92
The operational amplifier is the basic and important block in analog circuit. In recent years the supply voltage is scaled down in modern process, it will be a challenge to design the operational amplifier in such low supply voltage. Due to the popularity of mixed-mode integrated circuit design, digital circuit noise can easily couple to analog circuit through power path. A cascode compensation method will be used for enhance analog circuit power supply noise rejection ability. In switch-capacitor application the input capacitor of operational amplifier will affect the speed of whole circuit. A neutralization circuit skill will improve this problem in this thesis. A 1.1 voltage operational amplifier with high power supply rejection ratio is designed in this thesis using TSMC0.35μm 2P4M process .

APA, Harvard, Vancouver, ISO, and other styles

45

Lin, Bing-Jyun, and 林秉均. "Adjustable Phase-Shifted Full-Bridge High Voltage DC Power Supply with Fully Digital Controller." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/ftj3mr.

Full text

Abstract:

碩士
大同大學
電機工程學系(所)
102
An adjustable phase-shifted full-bridge high voltage dc power supply with fully digital controller is proposed in this paper. The proposed controller consists of a user interface control and a phase-shifted full-bridge control. By varying the phase-shifted angle calculated from the parameters entered in the user interface and the sampling output voltage, the output voltage is equal to the preset output voltage. In addition, the proposed system can achieve ZVS under various load conditions to reduce power loss. Next, a multi-range sampling circuit is proposed in this paper. This circuit can increase the precision of the output voltage and indirectly improve the ADC resolution while the output voltage is modulated in a wide range. Finally, the system efficiency is up to 94.2% at full load. In addition, the output voltage is close to the preset output voltage under various load conditions, and the voltage deviation is 0.005% ~ 0.49%

APA, Harvard, Vancouver, ISO, and other styles

46

Huang, Jian-Ming, and 黃建銘. "A High Voltage Power Supply with Continuous Adjustable Function for Corona Wind Radiating Application." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/48263873557637781948.

Full text

Abstract:

碩士
大同大學
電機工程學系(所)
102
A high voltage power supply with continuous adjustable function for corona wind radiating application is proposed in this thesis. First, the digital control scheme is adopted to overcome the problem for difficultly modulating the output voltage for traditional high voltage power supply. Moreover, the implemented single-transformer incorporating voltage multiplier structure and multi-transformers structure are used to compare the system performances. Next, all the mathematical models in the all operating mode are derived to get the corresponding relationship between the control signal and the output voltage. Furthermore, the prototype achieves electrical isolation and cost down by using the primary side control (PSR) technique to conduct the voltage feedback. In addition, the over current protection function is also incorporated into this system. Finally, the power factor corrector (PFC), auxiliary power circuit and high voltage power supply are integrated in the proposed system. Besides, all the simulation and experimental results are very close to the theory predictions.

APA, Harvard, Vancouver, ISO, and other styles

47

謝明泰. "Design of a High Voltage Power Supply for Traveling Wave Tube Using Feedforward Compensation." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/02437527780604889816.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Hsiang, Sing-Syue, and 向星學. "The Research on Diagnosis Wiring Connection with Meter of Facility of High Voltage Power Supply." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7wqdrq.

Full text

Abstract:

碩士
國立臺北科技大學
電機工程系所
102
In the process of power generation, transmission and distribution, the energy measurement is a very important part in power system. The high voltage consumers have watt-hour meter, var-hour meter, high voltage current transformer(CT) and high voltage Potential Transformer(PT) in the Meter of Facility(MOF). The failure of Metering devices contains internal components that operate in wrong way and wiring connect of human’s mistake, That will not accurately calculate the energy of customers. Therefore, the research is practical on the method of fault detection. In this study, according to the wiring structure of Taipower. Simulate plenty of fault models of meter incorrect wiring connection, And analyze the relation of electrical parameters. Finally, utilizing Borland C++ Builder designs a fast and accurate way to detect incorrect wiring connection, and reduce the probability of mistake by human’s determining. The result of this study shows that system can determine incorrect wiring connections accurately and monitor immediately. Consequently, this paper provides reference for Taipower and customers.

APA, Harvard, Vancouver, ISO, and other styles

49

Ku, Ying-Ying, and 古盈霙. "Design and Implementation of a High Voltage Power Supply for Portable Silent-Discharge Ozone Generators." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/04750801814454181922.

Full text

Abstract:

碩士
國立清華大學
電機工程學系
96
Ozone has strong sterilization capability and does not cause re-pollution to the environment. However, since it has a short half-life, meaning that it deoxidizes into oxygen in a short time span, makes it impossible to be put in mass production and store in containers. Hence, for small scale applications like in domestic use, a miniaturized ozone generator would be very convenient. The dielectric barrier ozone generator is one of the quietest types among all discharge ozone generators. Therefore, the main purpose of this thesis is focused to design and implement a high voltage power supply for miniaturized portable dielectric barrier discharge (also called the silent discharge) ozone generators for the use in indoor environments. Basically, the contributions of this thesis can be summarized as follows. First, propose a high voltage power supply for silent discharge ozone generators used for indoor applications and miniaturization demands. The high voltage power supply consists of two stages. The front stage is a boost-type power factor correction circuit to achieve low current harmonics and high power factor. The second stage is a half-bridge high frequency series-parallel resonant inverter with zero-voltage switching to achieve less voltage stress and higher efficiency. Second, some design criteria are given for designing the high voltage power supply by employing the high frequency equivalent circuit model of the ozone generator together with a burst mode control to achieve more robust output voltage under changing loads. Finally, a high voltage power supply with 80~270Vac 60Hz input, 2kVac 300kHz output, and 500W rated power is actually implemented. The power factor of the front stage PFC is 0.95~0.99, and the highest efficiency may reach 96%. The second stage high voltage inverter can achieve an efficiency of 87% approximately. It turns out that the overall efficiency can reach 83.5%. Also, it is seen that the constructed prototype can indeed achieve the expected performance.

APA, Harvard, Vancouver, ISO, and other styles

50

Chen, Yan-Jhang, and 陳晏彰. "Study and Implementation of a 30 kV High-voltage DC Power Supply with a Wide-range of Adjustable Output Voltage." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/56428955630551991376.

Full text

Abstract:

碩士
國立臺灣科技大學
電子工程系
100
This thesis mainly develops a 30 kV high-voltage DC power supply with a wide-range of adjustable output voltage. The power stage consists of a power factor corrector (PFC) and a buck current-fed push-pull DC-DC converter. The pre-stage PFC circuit is operated at boundary current conduction mode (BCM) to achieve high input power factor and provide a 380 V regulated DC voltage to the post-stage circuit. The buck current-fed DC-DC converter with a secondary voltage multiplier provides a high-voltage output from 5 kV to 30 kV with a rated power of 100W. A flyback converter is designed as the auxiliary power supply to provide two sets of 15V/0.2A and a 5V/2A for control stage. In this thesis, the operation principles and design considerations for the studied high-voltage power supply are discussed and analyzed. A laboratory prototype circuit is built and tested. The experimental results are shown to verify the feasibility of the proposed scheme.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'High Voltage Power Supply (HVPS)'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles