Dissertations / Theses on the topic 'Switched mode power supply'
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Reddy, Amarnath. "Expert system based switched mode power supply design." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/12842.
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The design of power electronic systems requires wide ranging expertise in complex and often tedious tasks, such as the design of the power circuit, selection of power semiconductor devices, design of the feedback loop, design of wound components, and design for Electromagnetic Compatibility (EMC). Many of the tasks rely heavily on the experience of the designer, and cannot be solved analytically. This makes the design iterative, time consuming, and heavily dependent on the designer's experience. At present, circuit simulation packages such as SPICE or SABER are used to test a design in software. Even with these tools, it is still necessary to build a prototype to verify the design, usually followed by several test-modify-retest cycles before a final design is reached. This process involves considerable decision making, which requires substantial expertise in all aspects of power electronics. This thesis investigates the use of expert system technology, one of many artificial intelligence techniques, to assist in the design of power electronic systems. Faster design times and a more efficient design are among the advantages that can be achieved using an expert system based design. In this study, Switched Mode Power Supplies have been chosen as a typical power electronic system. An expert system (developed using wxCLIPS) has been linked with a circuit simulator (SPICE), extensive databases and a graphical display system to provide a comprehensive design environment. The techniques used in the system cover all facets of the design: preliminary circuit design, component selection, circuit simulation, control loop design, and design for EMC. Extensive knowledge bases covering the various design rules are built into the expert system. The design methodology aims to give a near complete system design with an optimum configuration produced at minimum time and cost. The investigated techniques could readily be adapted to other power electronic applications, such as Uninterruptible Power Supplies and motor drives.
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Gartner, Andy Michael. "The development of a 100 KHZ switched-mode power supply." Thesis, Cape Technikon, 1991. http://hdl.handle.net/20.500.11838/1168.
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Thesis (Masters Diploma (Electricity Engineering) -- Cape Technikon, Cape Town,1991At the time of the design the maximum allowable operating frequency for an output power of between 200 and 250 watts was 100 kHz. Although a 600 kHz operating frequency could have been achieved, it would only be at a very low output power level. To maximise the current components available, a 210 watt 100 kHz direct-off-line switched-mode power supply was developed. The design presented can be used to power any compatible IBM XT/AT personal computer. The prototype was tested. An overall efficiency of 61% was achieved. The final prototype required 1 521 cm3 and weighed approximately 980 g, representing a power to volume ratio of 0.14 W/cm3 (2.26 W/inch3). Detailed procedures are also presented to help with the design and selection of the reactive components. Special design features include the half-bridge push-pull topology, MOSFETS as power switches, digital current limiting, primary power limiting, multiple outputs and fault counting to name but a few.
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Nuttall, Daniel Robert. "Advanced high frequency switched-mode power supply techniques and applications." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/advanced-high-frequency-switchedmode-power-supply-techniques-and-applications(5792cb86-58e3-488b-b27e-559c18e55250).html.
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This Thesis examines the operation and dynamic performance of a single-stage, single-switch power factor corrector, S4 PFC, with an integrated magnetic device, IM. Also detailed isthe development and analysis of a high power light emitting diode, HP LED, power factorcorrection converter and proposed voltage regulation band control approach.The S4 PFC consists of a cascaded discontinuous current mode, DCM, boost stage anda continuous current mode, CCM, forward converter. The S4 PFC achieves a high powerfactor, low input current harmonics and a regulated voltage output, utilising a singleMOSFET. A steady-state analysis of the S4 PFC with the IM is performed, identifying theoperating boundary conditions for the DCM power factor correction stage and the CCMoutput voltage regulation stage. Integrated magnetic analysis focuses on understanding theperformance, operation and generated flux paths within the IM core, ensuring the device doesnot affect the normal operation of the converter power stage. A design method for the S4 PFCwith IM component is developed along with a cost analysis of this approach. Analysis predictsthe performance of the S4 PFC and the IM, and the theoretical work is validated by MATLABand SABER simulations and measurements of a 180 W prototype converter.It is not only the development of new topological approaches that drives theadvancement of power electronic techniques. The recent emergence of HP LEDs has led to aflurry of new application areas for these devices. A DCM buck-boost converter performs thepower factor correction and energy storage, and a cascaded boundary conduction current modebuck converter regulates the current through the LED arrays. To match the useful operatinglifetime of the HP LEDs, electrolytic capacitors are not used in the PFC converter. Analysisexamines the operation and dynamic characteristics of a PFC converter with low capacitiveenergy storage capacity and its implications on the control method. A modified regulationband control approach is proposed to ensure a high power factor, low input current harmonicsand output voltage regulation of the PFC stage. Small signal analysis describes the dynamicperformance of the PFC converter, Circle Criterion is used to determine the loop stability.Theoretical work is validated by SABER and MATLAB simulations and measurements of a180 W prototype street luminaire.
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Petkov, Roumen Dimitrov. "High power switched mode magnetron power supply systems for industrial microwave heating applications." Thesis, Teesside University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259645.
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Chew, W. M. "Optimum electromagnetic design for wound components in SMPS applications." Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328339.
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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.
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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.
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Wong, Fu Keung, and n/a. "High Frequency Transformer for Switching Mode Power Supplies." Griffith University. School of Microelectronic Engineering, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050211.110915.
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A power supply is an essential part of all electronic devices. A switching mode power supply is a light weight power solution for most modern electronic equipment. The high frequency transformer is the backbone of modern switched mode power supplies. The skin effect and proximity effects are major problems in high frequency transformer design, because of induced eddy currents. These effects can result in transformers being destroyed and losing their power transferring function at high frequencies. Therefore, eddy currents are unwanted currents in high frequency transformers. Leakage inductance and the unbalanced magnetic flux distribution are two further obstacles for the development of high frequency transformers. Winding structures of power transformers are also a critical part of transformer design and manufacture, especially for high frequency applications. A new planar transformer with a helical winding structure has been designed and can maintain the advantages of existing planar transformers and significantly reduce the eddy currents in the windings. The maximum eddy current density can be reduced to 27% of the density of the planar transformer with meander type winding structure and 33% of the density of the transformer with circular spiral winding structure at an operating frequency of 1MHz. The voltage ratio of the transformer with helical winding structure is effectively improved to 150% of the voltage ratio of the planar transformer with circular spiral coils. With the evenly distributed magnetic flux around the winding, the planar transformer with helical winding structure is excellent for high frequency switching mode power supplies in the 21st Century.
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Wong, Fu Keung. "High Frequency Transformer for Switching Mode Power Supplies." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367650.
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A power supply is an essential part of all electronic devices. A switching mode power supply is a light weight power solution for most modern electronic equipment. The high frequency transformer is the backbone of modern switched mode power supplies. The skin effect and proximity effects are major problems in high frequency transformer design, because of induced eddy currents. These effects can result in transformers being destroyed and losing their power transferring function at high frequencies. Therefore, eddy currents are unwanted currents in high frequency transformers. Leakage inductance and the unbalanced magnetic flux distribution are two further obstacles for the development of high frequency transformers. Winding structures of power transformers are also a critical part of transformer design and manufacture, especially for high frequency applications. A new planar transformer with a helical winding structure has been designed and can maintain the advantages of existing planar transformers and significantly reduce the eddy currents in the windings. The maximum eddy current density can be reduced to 27% of the density of the planar transformer with meander type winding structure and 33% of the density of the transformer with circular spiral winding structure at an operating frequency of 1MHz. The voltage ratio of the transformer with helical winding structure is effectively improved to 150% of the voltage ratio of the planar transformer with circular spiral coils. With the evenly distributed magnetic flux around the winding, the planar transformer with helical winding structure is excellent for high frequency switching mode power supplies in the 21st Century.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Microelectronic Engineering
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Vuckovic, Ashlee. "The effects of varying the frequency of a switched mode power supply controlled DC motor." Thesis, Vuckovic, Ashlee (2015) The effects of varying the frequency of a switched mode power supply controlled DC motor. Other thesis, Murdoch University, 2015. https://researchrepository.murdoch.edu.au/id/eprint/28661/.
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In industry DC machines are still used today due to their torque-speed characteristics [1]. The DC motors speed characteristics can be further enhanced by the addition of external electronic controls, such as buck converters. [2]. However, the addition of these external electronic controls to the DC motor also adds a complexity to these type of systems and problems can also arise from these buck converter/DC motor configurations [2].
This thesis examines the complexities that arise from these type of systems, in particular how these complexities effect that the speed-torque characteristics of a separately excited DC Motor may have during Discontinuous Conduction Mode (DCM) and Continuous Conduction Mode (CCM).
To demonstrate the affects that Discontinuous Conduction Mode and Continuous Conduction Mode has on the speed-torque characteristics of a DC motor, a setup was designed and constructed with the following design objectives:
• Convert AC power from mains to regulated DC power, using a power supply that must:
o Supply power to a DC motor
o Operate with a variable switching frequency from a few Hz – 2 kHz
o Operate with a variable voltage from 0 – 240 V
o And have a maximum current output of 1.5 A
• The setup must be able to measure the speed, load torque, the armature current and voltage waveforms must also be observable and produce speed-torque curves of the DC motor
Once completed, the setup was used to examine the speed-torque characteristics of the DC motor setup. The setup was able to meet all the design objectives. The results from the setup demonstrated a nonlinear region during DCM operation and a linear region CCM operation, in speed-torque curves of the setup. The main observations from the setup showed that the torque-speed curves experienced a larger nonlinear region at lower switching frequencies when compared to the torque-speed curves of systems that were operating at higher frequencies. Additionally, it was found that at higher voltages, the speed-torque curves experienced a smaller linear region when compared with the speed-torque curves of systems at lower voltages.
Further analysis revealed the speed characteristic of the system was mainly caused by dramatic voltage drops over the armature of the motor, and that the dramatic voltage drops occurred during DCM, when load was applied to the motor.
A simulation of the final setup was produced, although the simulation model could benefit from further improvements and modifications. The model was able to demonstrate some general trend that was observed in the results section.
The setup was also adapted for future use as teaching aid that was aimed at 3rd year engineering students at Murdoch University. The purpose of the setup was to contribute to the student’s basic understandings of motor operation during DCM and CCM. A student laboratory exercise was successfully completed as part of project objectives. The project setup can be replicated in a laboratory environment and used to demonstrate the effects that DCM and CCM, have speed-torque characteristics of a DC Motor
Overall, this project was considered to be successful, as all the objectives were completed during the course of the thesis project.
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Doss, Gary Richard Jr. "Novel Intelligent Power Supply Using A Modified Pulse Width Modulator." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1253576739.
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Kutluay, Koray. "Fully Digital Parallel Operated Switch-mode Power Supply Modules For Telecommunications." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606640/index.pdf.
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Digitally-controlled, high power universal telecommunication power supply modules have been developed. In this work, the converter control strategy, and its design and implementation first, by means of parallel-operated, dual, 8-bit microcontrollers, and then by using a high processing power digital signal processor (DSP) have been emphasized. The proposed dual-processor based digital controller provides an extended operating output voltage range of the power supplies, user programmable current limit setting, serial communication based active load current sharing with automatic master-slave selection among parallel-operated modules, user selectable number of back-up battery cells,
programmable temperature compensation curves, and automatic derating without extra hardware requirement. Overload and output short-circuit protection features are also controlled by software.
One of the processors in the digital controller is employed for user interface purposes such as long term records, display, and alarm facilities, and remote control, which are inherently slow processes. The fast processing speed required by output voltage setting, current limit, and load current sharing however is to be fulfilled by a second processor dedicated to the adjustment of output voltages of modules. Tight dynamic load regulation requirement of a telecommunication power supply has been fulfilled by a 150 MIPS DSP, in place of a low cost, 8-bit microcontroller.
The implemented digitally-controlled, 1.8 kW, 0-70V telecommunication power supplies have been tested successfully in several locations in the field.
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Kaya, Ibrahim. "A Switch Mode Power Supply For Producing Half Wave Sine Output." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609781/index.pdf.
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In this thesisanalysis, design and implementation of a DC-DC converter with active clamp forward topology is presented. The main objective of this thesis is generating a rectified sinusoidal voltage at the output of the converter. This is accomplished by changing the reference signal of the converter. The converter output is applied to an inverter circuit in order to obtain sinusoidal waveform. The zero crossing points of the converter is detected and the inverter drive signals are generated in order to obtain sinusoidal waveform from the output of the converter. Next, the operation of the DC-DC converter and sinusoidal output inverter coupled performance is investigated with resistive and inductive loads to find out how the proposed topology performs. The design is implemented with an experimental set-up and steady state and dynamic performance of the designed power supply is tested. Finally an evaluation of how better performance can be obtained from this kind of arrangement to obtain a sinusoidal output inverted is thoroughly discussed
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Nasir, Nasir. "Development of novel low noise switch-mode power supply designs for high fidelity audio power amplifiers." Thesis, Bournemouth University, 2017. http://eprints.bournemouth.ac.uk/29795/.
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Today, linear power supplies are widely used to provide the supply voltage rail to an audio amplifier and are considered bulky, inefficient and expensive due to the presence of various components. In particular, the typical requirements of linear designs call for physically large mains transformers, energy storage/filtering inductors and capacitors. This imposes a practical limit to the reduction of weight in audio power systems. In order to overcome these problems, Switch-mode Power Supplies (SMPS) incorporate high speed switching transistors that allow for much smaller power conversion and energy storage components to be employed. In addition the low power dissipation of the transistors in the saturated and off states results in higher efficiency, improved voltage regulation and excellent power factor ratings. The primary aim of this research was to develop and characterize a novel low noise switch mode power supply for an audio power amplifier. In this thesis, I proposed a novel balancing technique to optimize the design of SMPS that elevate the performance of converter and help to enhance the efficiency of power supply through high speed switching transistors. In fact, the proposed scheme mitigates the noise considerably in various converter topologies through different mechanisms. To validate the proposed idea, the technique is applied to different converters e.g; PFC boost converter, flyback converter and full-bridge converter. The performance of audio amplifier is evaluated using designed SMPS to compare with existing linear power supply. On the basis of experimental results, the decision has been made that the proposed balanced SMPS solution is as good as linear solution. Due to novelty and universality of balancing technique, it can provide a new path for researchers in this field to utilize the SMPS in all other audio devices by further enhancing its efficiency and reducing system noise.
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Klejma, Michael. "Svářečka MIG/MAG se spínaným zdrojem." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-318095.
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This diploma thesis deals with design of welding power supply for MIG / MAG and MMA technique with continuous output current 120 A. The first, theoretical part is devoted to welding process technology, physical characteristics of electric arc and description of individual welding methods. The thesis also deals with the concept of power converter. The design of the switched-mode power supply is based on a full bridge topology. In order to implement advanced controls of welding power supply, the ARM Cortex M4 microprocessor was selected. Due to the large power consumption of the stepper motor for drive the welding wire, an auxiliary switched-mode power supply was also implemented. The documentation describing the realization of the welding power supply and the results of the measurements are in the last part of the thesis. The welding power supply was successfully revived and reached nominal parameters. Inert gas welding has not been tested yet, due to lack of time caused by extensive work in order to complete mechanical realization.
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Al-Baidhani, Humam A. "Design and Implementation of Simplified Sliding-Mode Control of PWM DC-DC Converters for CCM." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1590930594283361.
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Hrubý, Lukáš. "Napájecí zdroj pro vesmírné aplikace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377071.
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The following work deals with a design of switched mode power supply. In this essay, there is detailed description of non-isolated and isolated topologies of SMPS, used in industry. Next, there are calculations for design and analysis which are needed for space design. There will also be selected devices, which could be used in final device. Based on experience and ECSS requirements, there will be chosen parameters of SMPS, which could be then used as a module for future space design. Chosen topology of SMPS will be created as engineering model assembled with commercial components. One part of this work is dedicated to design and realization of planar transformer and coupled inductor.
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Jorda, Ivo. "Univerzální napájecí zdroj s mikrokontrolérem." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220573.
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The aim of this thesis is design of adjustable switched mode power supply with symmetrical output of 25 V, and switched mode power supply with fixed output voltage of 5 V. Required maximum output current of each outputs is 3 A. At the beginning of the paper function of the basic SMPS topologies is described. Next all reqiured SMPSs are designed and chosen parts of the design are simulated. In the second half of the thesis assembly and testing of PCB are described as well as functions of programs. Last chapter contains results of meassurement of power supply paramters.
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Xie, Manjing. "Digital Control for Power Factor Correction." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/34258.
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This thesis focuses on the study, implementation and improvement of a digital controller for a power factor correction (PFC) converter.
The development of the telecommunications industry and the Internet demands reliable, cost-effective and intelligent power. Nowadays, the telecommunication power systems have output current of up to several kilo amperes, consisting of tens of modules. The high-end server system, which holds over 100 CPUs, consumes tens of kilowatts of power. For mission-critical applications, communication between modules and system controllers is critical for reliability. Information about temperature, current, and the total harmonic distortion (THD) of each module will enable the availability of functions such as dynamic temperature control, fault diagnosis and removal, and adaptive control, and will enhance functions such as current sharing and fault protection. The dominance of analog control at the modular level limits system-module communications. Digital control is well recognized for its communication ability. Digital control will provide the solution to system-module communication for the DC power supply.
The PFC converter is an important stage for the distributed power system (DPS). Its controller is among the most complex with its three-loop structure and multiplier/divider. This thesis studies the design method, implementation and cost effectiveness of digital control for both a PFC converter and for an advanced PFC converter. Also discussed is the influence of digital delay on PFC performance. A cost-effective solution that achieves good performance is provided. The effectiveness of the solution is verified by simulation.
The three level PFC with range switch is well recognized for its high efficiency. The range switch changes the circuit topology according to the input voltage level. Research literature has discussed the optimal control for both range-switch-off and range-switch-on topologies. Realizing optimal analog control requires a complex structure. Until now optimal control for the three-level PFC with analog control has not been achieved. Another disadvantage of the three-level PFC is the output capacitor voltage imbalance. This thesis proposes an active balancing solution to solve this problem.Master of Science
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Melša, Vojtěch. "Výkonový audio zesilovač využívající AC/DC měnič." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219827.
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The aim of this work was to design and construct a simple audio amplifier, which would be based of involvement and components used in switching power sources on the maximum degree (for example from usual ATX sources for computer). The main motivation for development is the existence of many old sources that do not use and big interest of users for the construction of home audio amplifiers for small and medium power. Amplifiers based on switching power sources with greater efficiency and less weight than comparable classic amplifiers (working in classes A, B or AB). Their disadvantage is the complicated design and introduction of distortion and spurious signals to the amplified signal. This work will be described a design of simple amplifier, which will minimize these negative effects. For shortcomings and wrong parameters this proposed involvement will be eventually described and implemented design of amplifier in class D.
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Dias, Agnaldo Vieira. "Sistema de alimentação chaveado para modulador de pulsos com linha de retardo aplicado em sistema radar = Switching mode system to supply pulse modulators based in pulse forming network applied to radar." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258992.
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Orientador: Ernesto Ruppert FilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-21T00:56:13Z (GMT). No. of bitstreams: 1 Dias_AgnaldoVieira_M.pdf: 2229736 bytes, checksum: 725a7fa267bc30780c457689e4356336 (MD5) Previous issue date: 2012
Resumo: O estudo da utilização de conversores CC/CC isolados e elevadores de tensão para a alimentação de moduladores de pulsos é apresentado neste trabalho. Foi selecionada a topologia em ponte completa, dando-se enfoque ao problema das capacitâncias parasitas envolvidas no circuito, que aparecem de forma acentuada em transformadores elevadores de tensão e filtros indutivos de saída e são altamente indesejáveis quando se opera em regime chaveado. Essas capacitâncias são tratadas através de uma forma de amortecimento, onde a energia armazenada nas mesmas é devolvida à fonte primária ao final de cada semiciclo de chaveamento, tentando obter-se menor volume, maior rendimento e menor dissipação de calor no conversor. Além disso, um circuito de regulação de carga é utilizado para garantir uma maior estabilidade de pulso e contornar problemas típicos de moduladores de pulsos utilizados em radares, como o efeito de backswing. O modulador de pulsos utilizado como carga para esse sistema opera com uma tensão de alimentação de 1kV, frequência de repetição de pulsos (PRF) de 585Hz e consome uma potência da ordem de 2,1kW. O conversor CC/CC é alimentado por um barramento CC não regulado de 280V
Abstract: The study of high-voltage isolated DC/DC converters used to supply pulse modulators is presented on this dissertation. The Full Bridge topology was selected, focusing in problems caused by parasitic capacitances in the circuit. This characteristic, which appears sharply in high voltage transformers and in inductors of output filter, is highly undesirable when the circuit is operated in switching mode. These capacitances are handled using a soft commutation technique, where their stored energy are returned to the primary source in the end of each switching cycle, trying to get a low size, high efficiency and low heat dissipation in the converter. Moreover, a charging regulator circuit is used to ensure good pulse stability and avoid typical problems in the pulse modulators use, such as the backswing effect. The pulse modulator used as load for this converter operates with a supply voltage of 1kV, pulse repetition frequency (PRF) of 585Hz and consumes 2.1 kW. The converter input is supplied by a 280V unregulated DC bus
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica
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Šír, Michal. "Laboratorní napájecí zdroj s digitální řídicí jednotkou." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242115.
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This project deals with a design of power and control circuits for a laboratory power supply source, consisting of a continuous conduction mode active rectifier and DC/DC converter. Detailed design of input rectifier with active power factor correction, DC/DC converter and control circuits with their implementation to digital signal processor are the project results.
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Arntzen, Chris. "THE BICYCLE-POWERED SMARTPHONE CHARGER." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1008.
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This thesis entails the design and fabrication of a smartphone charger that is powered by a bicycle dynamo hub. In addition to the design and validation of the charger prototype, this thesis involves the testing and characterization of the dynamo hub power source, the design and construction of specialized test equipment, and the design and prototyping of a handlebar-mounted case for the smartphone and charging electronics. With the intention of making the device a commercial product, price, aesthetics, and marketability are of importance to the design. An appropriate description of the charger circuit is a microcontroller-based energy management system, tailored to meet strict power demands of current smartphones. The system incorporates a switched-mode power supply, lithium polymer battery, microcontroller, and specialized protection circuitry. Prototype testing confirms that the circuit meets the charging requirements of the smartphone at bicycle speeds ranging from 7 miles per hour to as high as 55 miles per hour.
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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.
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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.
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Mitáš, Daniel. "Ovládací rozhraní CNC frézky." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219821.
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This project deals with portal-type CNC milling machine design and construction. CNC milling machine should be able to machining light metals and alloys. This document contains description of mechanical components selection, machine frame design and building, design and construction of USB motion control unit and also contains control software description and user manual.
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Baglan, Fuat Onur. "Design Of An Educational Purpose Multifunctional Dc/dc Converter Board." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12610103/index.pdf.
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In this thesis a multifunctional DC/DC converter board will be developed for utilization as an educational experiment set in the switched-mode power conversion laboratory of power electronic courses. The board has a generic power-pole structure allowing for easy configuration of various power converter topologies and includes buck, boost, buck-boost, flyback, and forward converter topologies. All the converters can be operated in the open-loop control mode with a switching frequency range of 30-100 kHz and a maximum output power of 20 W. Also the buck converter can be operated in voltage mode control and the buck-boost converter can be operated in peak-current-mode control for the purpose of demonstrating the closed loop control performance of DC/DC converters. The designed board allows for experimentation on the DC/DC converters to observe the macroscopic (steadystate/ dynamic, PWM cycle and low frequency) and microscopic (switching dynamic) behavior of the converters. In the experiments both such characteristics can be clearly observed such that students at basic learning level (involving only the macroscopic behavior), and students at advanced learning level (additionally involving the parasitic effects) can benefit from the experiments. The thesis reviews the switch mode conversion principles, gives the board design and proceeds with the experiments illustrating the capabilities of the experimental system.
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Žamberský, Jan. "Zvyšující měnič napětí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-241973.
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Práce se zabývá popisem jednotlivých typů zdrojů s důrazem na izolované topologie. Poté je rozebírána nejvhodnější volba pro zdroj na anodické bondování, kde jsou kladeny požadavky na vysoké výstupní napětí s malým proudem. Další část rozebírá problematická místa návrhu a na co je třeba dávat pozor. Poté je proveden vlastní návrh zdroje s popisem optimalizačních kroků. Tento zdroj je odsimulován. Dva rozdílné přístupy k realizaci takového zdroje jsou poté porovnány a nejlepší je vybrán. Je ukázána možnost, jak realizovat bipolární výstup. V poslední části je tento zroj sestaven a proměřeny jeho parametry.
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Deniéport, Romain. "Amélioration du rendement énergétique et de la dynamique d'entrée de convertisseurs d’énergie isolés par l’utilisation de techniques analogiques et numériques de commande." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112381.
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Les travaux présentés ici proposent des convertisseurs d’énergie à haut rendement et très large dynamique de tension d’entrée, c'est-à-dire capables de fonctionner avec un rendement énergétique élevé sur une plage de tension d’entrée étendue (typiquement de 9V à 200V). De multiples tensions de réseaux sont standards dans l’industrie : elles sont spécifiques à un domaine (aéronautique, ferroviaire, …) et dépendent de la source primaire d’alimentation électrique (batterie d’accumulateurs, génératrice, …). Au sein d’un équipement embarqué, plusieurs réseaux peuvent cohabiter : une alimentation principale 110V et une alimentation de secours sur batterie 12V, par exemple. Le besoin de convertisseurs large dynamique d’entrée est donc une réalité, mais il n’existe sur le marché que peu de convertisseurs capables de réaliser une dynamique d’entrée supérieure à dix. Dans un premier temps, nous avons étudié les enjeux et les problématiques liés à la large dynamique d’entrée, afin de mieux cerner les limitations des topologies de puissance classiques. Nous avons ensuite traité le cas d’une architecture de conversion d’énergie de type série, dont nous avons amélioré le rendement énergétique grâce à l’utilisation de circuits d’aide à la commutation. Cette solution ayant des performances limitées, nous avons proposé de nouvelles architectures de convertisseurs DC/DC, de type parallèle, capables de supporter des dynamiques de tension d’entrée supérieures à vingt et ayant un rendement énergétique élevé (supérieur à 80%). Nous avons également étudié et mis en œuvre des stratégies de commande, numériques et analogiques, permettant de contrôler ces nouvelles topologies complexesPower converters are present in virtually every embedded system, but many standards of DC networks exist: the supply voltage is depending on how the power is generated (battery, alternator …) and can range from 12V to more than 115V. When an equipment must comply with a 110V main supply and 12V back-up supply, the use of a wide input voltage range DC/DC converter is mandatory. Since classical switched mode power converters cannot achieve simultaneously high efficiency and wide input voltage range, manufacturers rarely propose DC/DC converters with an input voltage range greater than 10. This work tackles the issue of wide input voltage power conversion. After discussing about designs trade off and problems that stem from a wide input range, we try to improve the overall efficiency of a classical buck-boost converter, by using non dissipative switching-aid circuits. We also proposed a novel two stages power converter capable of dealing with very wide input voltage ranges (more than 20), without a reduction of the power efficiency. Since those new converters are far more difficult to control, some theoretical analysis was performed and some practical tests were done using complex controls laws
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Forsyth, A. J. "Switched-mode power conversion." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233948.
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The thesis begins with a general introduction to switched-mode power conversion. The main application areas of the technique are outlined and a summary is presented of current research work. The following chapters then focus on one recent development in the field, the Cuk converter and integrated magnetics. First, the steady-state performance limitations of the Cuk converter are explored through a comparison with the basic switched-mode converter topologies. The circuit is seen to possess several attractive properties including input and output current waveforms which are continuous rather than pulsating. However, the switching losses are shown to be high. A regenerative snubber is presented which reduces the transistor turn-off loss whilst preserving the high-quality input and output current waveforms of the converter. The integrated magnetics technique is discussed in the following chapter. This is the technique whereby converter magnetic components are coupled to eliminate input and output ripple currents and therefore improve steady-state performance. The possible problems are highlighted of attempting to couple transformers and inductors on a single core and an alternative coupling technique is outlined which uses an auxiliary electric circuit. The introduction of magnetic coupling in the Cuk converter to eliminate input and output ripple currents and improve steady-state performance results in more complicated dynamic characteristics and a more complex control problem. The state-space averaging technique is used in chapter 4 with the aid of a control engineering design package, CLADP, to analyse the problem. The impact of component coupling on the converter dynamic characteristics is explained and possible control strategies are suggested and verified. Finally, the Cuk converter with component coupling is assessed as a large-signal waveshaper. Several inverter configurations are examined in which a switched-mode converter operating under closed-loop control is used as a waveshaper to synthesise high-quality sinusoidal output currents. The implementation of the schemes using a Cuk converter with component coupling is described.
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Botek, Lukáš. "Dvojčinný síťový spínaný zdroj." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-412970.
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This master´s thesis describes switch mode power supply and discusses the design of its individual parts. It also contains a simulation of the power part of the converter and a reseach in the area of DC/DC converters.
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Zatloukal, Tomáš. "Platforma pro ladění spínaných zdrojů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-433291.
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The following work deals with a design of power supply testbench with design of their replaceable modules and circuits for their measurement. The final product should be used for faster design and tuning of switching power supplies. In this essay, there is detailed description of switching power supplies, analysis of support circuits and calculations for design. Based on theoretical background and selected parameters, a connection concept will be created. This concept will be validated by a device that will consist of main board, changeable modules and measurement circuits.
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Wall, Simon Robert. "Control of switched-mode power converters." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362966.
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Li, Bo. "Conception et test de cellules de gestion d'énergie à commande numérique en technologies CMOS avancées." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00782429.
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Les technologies avancées de semi-conducteur permettent de mettre en œuvre un contrôleur numérique dédié aux convertisseurs à découpage, de faible puissance et de fréquence de découpage élevée sur FPGA et ASIC. Cette thèse vise à proposer des contrôleurs numériques des performances élevées, de faible consommation énergétique et qui peuvent être implémentés facilement. En plus des contrôleurs numériques existants comme PID, RST, tri-mode et par mode de glissement, un nouveau contrôleur numérique (DDP) pour le convertisseur abaisseur de tension est proposé sur le principe de la commande prédictive: il introduit une nouvelle variable de contrôle qui est la position de la largeur d'impulsion permettant de contrôler de façon simultanée le courant dans l'inductance et la tension de sortie. La solution permet une dynamique très rapide en transitoire, aussi bien pour la variation de la charge que pour les changements de tension de référence. Les résultats expérimentaux sur FPGA vérifient les performances de ce contrôleur jusqu'à la fréquence de découpage de 4MHz. Un contrôleur numérique nécessite une modulation numérique de largeur d'impulsion (DPWM). L'approche Sigma-Delta de la DPWM est un bon candidat en ce qui concerne le compromis entre la complexité et les performances. Un guide de conception d'étage Sigma-Delta pour le DPWM est présenté. Une architecture améliorée de traditionnelles 1-1 MASH Sigma-Delta DPWM est synthétisée sans détérioration de la stabilité en boucle fermée ainsi qu'en préservant un coût raisonnable en ressources matérielles. Les résultats expérimentaux sur FPGA vérifient les performances des DPWM proposées en régimes stationnaire et transitoire. Deux ASICs sont portés en CMOS 0,35µm: le contrôleur en tri-mode pour le convertisseur abaisseur de tension et la commande par mode de glissement pour les convertisseurs abaisseur et élévateur de tension. Les bancs de test sont conçus pour conduire à un modèle d'évaluation de consommation énergétique. Pour le contrôleur en tri-mode, la consommation de puissance mesurée est seulement de 24,56mW/MHz lorsque le ratio de temps en régime de repos (stand-by) est 0,7. Les consommations de puissance de command par mode de glissement pour les convertisseurs abaisseur et élévateur de tension sont respectivement de 4,46mW/MHz et 4,79mW/MHz. En utilisant le modèle de puissance, une consommation de la puissance estimée inférieure à 1mW/MHz est envisageable dans des technologies CMOS plus avancées. Comparé aux contrôlés homologues analogiques de l'état de l'art, les prototypes ASICs illustrent la possibilité d'atteindre un rendement comparable pour les applications de faible et de moyen puissance mais avec l'avantage d'une meilleure précision et une meilleure flexibilité.
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Šlezingr, Jan. "Parametrizace mezních křivek odolnosti elektrických spotřebičů na krátkodobé poklesy a výpadky napětí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217724.
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This master’s thesis work deal with diagnosis parameters immunity curves uniphase appliance on short - term voltage dips a interuption. Immunity curve is dependence smallest possible sizes RMS voltage for performance given to criteria function on time continuation voltage event. Curves of resistance is different for each electric appliance, and depending on the size and over-voltage network, the burden on resources and voltage during the event.. The goal of this work is to devise a methodology for measuring the implementation of parametric measurement limit curves of resistance for selected types of appliances.
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Hallworth, Michael. "Digital peak current mode control of switched-mode power supplies." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602418.
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Peak current mode control is a popular method of SMPS control due the inherent cycle-by- cycle current limiting, feed-forward control and current sharing ability it provides. However, the subharmonic oscillations which plague peak current mode control must be removed using slope compensation. Until the work presented in this thesis, there have been no true digital implementations of peak current mode control due to the difficulties associated with implementing a digital form of slope compensation. This thesis introduces a complete digital peak current mode converter which uses a novel method of digital slope compensation to remove the subharmonic oscillations observed when using peak current mode control. The digital implementation of peak current mode control is applied to a Buck converter design example which directly compares the proposed digital scheme with an equivalent analog scheme. Exact analytical design equations are derived which allow a specified crossover frequency and phase margin to be achieved concurrently. The l6W Buck converter design example compares the digital peak current mode controlled converter with an analog converter designed to the same specification and tested on the same power stage PCB. The detailed steady state, transient and frequency response results from the hardware experimentations show excellent correlation with the MATLAB simulated converter and are in good agreement with the equivalent analog converter. The crossover frequency is specified as 15kHz and is measured as 14.71kHz on the proposed digital converter with a measured phase margin only 5' less than the specification. The results confirm that the operation of the proposed digital peak current mode control scheme is functionally similar to analog peak current mode control.
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Kadlec, Josef. "Spínané zdroje velkých výkonů - paralelní řazení zdrojů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-234609.
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This doctoral thesis deals with the issue of high power switched-mode power supplies that are designed as modular systems. The thesis describes series, parallel and series-parallel possibility of connected converters. System can achieve extremely high output current for converters connected in parallel. For converters connected in series, the system can achieve extremely high output voltage. The main goal of this thesis is to develop so-called reconfigurable modular system. It is a system that can change converters connection of serial, parallel or series-parallel connection - during its operation. This option to change converters connection significantly extends the control range of output voltage and output current of the whole system. For all these mentioned variants of the modular system there are described and simulated suitable control schemes. The issue of interleaved PWM is described in the thesis. Output voltage ripple and current ripple equations were derived for each converters connection. These equations, which were derived either for systems with interleaved PWM or for systems without of phase shifted PWM, are also proved by simulations. Design of reconfigurable modular system with power of 9.6 kW that contains four converters was introduced in this thesis. Converters use modern transistors and diodes of SiC material. The proposed reconfigurable modular system was successfully manufactured. The measurement results are also shown in the work.
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Bodetto, Dallera Mirko Andrés. "Contribución al diseño de convertidores de tipo elevador-reductor para alimentación de sistemas de iluminación en leds." Doctoral thesis, Universitat Rovira i Virgili, 2015. http://hdl.handle.net/10803/312827.
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.En aquesta tesis doctoral es presenta el disseny i implementació d’un sistema d’alimentació ac-dc basat en convertidors de tipus elevador-reductor d’única etapa. El sistema s’ha dissenyat per regular el corrent d’alimentació d’un conjunt de LEDs connectats en sèrie. El sistema d’alimentaciódissenyat té la capacitat de mantenir constant el flux lumínic dels LEDs i permet la dimerització en un ampli rang de valors de corrent. Simultàniament, el sistema manté un nivell molt baix d’harmònics introduïts a la xarxa de corrent altern.
L’anàlisi ha demostrat la viabilitat en l’aplicació del control en mode lliscant per a la imposició d’un comportament como resistor lliure de pèrdues (LFR) en convertidors de tipus elevador-reductor d’ordre elevat (Ćuk, SEPIC i Shepard-Taylor) en els que es pretengui simultàniament regular el corrent de sortida. En aquest context, s’ha exposat en detall l’anàlisi dinàmic, i posterior disseny del llaç de regulació de corrent, del LFR basat en el convertidor Ćuk quan s’alimenta a través d’una font de corrent alterna de 230 Vrms-50 Hz.
Un dels problemes trobats ha estat l’aparició de distorsió a la forma d’ona del corrent d’entrada en els passos per zero. Aquesta distorsió impedeix, per baixes potències d’entrada, el compliment de la norma d’introducció d’harmònics i, per tant, limita el seu ús en aplicacions de dimerització. S’ha proposat una solució basada en la modulació de la finestra d’histèresi de tal forma que a la proximitat del pas per zero la freqüència de commutació del convertidor augmenta. Mitjançant aquesta tècnica es garanteix tant el compliment de las normes preceptives com un rang de dimerització del 0 al 100 %.
Las previsions teòriques s’han verificat mitjançant simulació i a partir de prototipus experimentals.En esta tesis doctoral se presenta el diseño e implementación de un sistema de alimentación AC-DC basado en convertidores de tipo elevador-reductor de única etapa. El sistema se ha diseñado para regular la corriente de alimentación de un conjunto de LEDs conectados en serie. Este tiene la capacidad de mantener constante el flujo lumínico de los LEDs y permite la dimerización en un amplio rango de valores de corriente. Simultáneamente, el sistema mantiene un nivel muy bajo de armónicos introducidos a la red de corriente alterna. El análisis ha demostrado la viabilidad en la aplicación del control en modo deslizante para la imposición de un comportamiento como resistor libre de pérdidas (LFR) en convertidores de tipo elevador-reductor de orden elevado (Ćuk, SEPIC y Shepard-Taylor) en los que se pretenda simultáneamente regular la corriente de salida. En este contexto, se ha expuesto en detalle el análisis dinámico, y posterior diseño del lazo de regulación de corriente, del LFR basado en el convertidor Ćuk cuando se alimenta a través de una fuente de corriente alterna de 230 Vrms-50 Hz. Uno de los problemas encontrados ha sido la aparición de distorsión en la forma de onda de la corriente de entrada en los cruces por cero. Dicha distorsión impide, para bajas potencias de entrada, el cumplimiento de la norma de introducción de armónicos y, por tanto, limita su utilización para aplicaciones de dimmerización. Se ha propuesto una solución basada en modulación de la ventana de histéresis de tal forma que en las cercanías del cruce por cero la frecuencia de conmutación del convertidor aumenta. Mediante esta técnica se garantiza tanto el cumplimiento de las normas preceptivas como un rango de dimerización del 0 al 100 %. Las previsiones teóricas se han verificado mediante simulación y a partir de prototipos experimentales.
In this thesis, the design and implementation of an ac-dc power factor correction system based on single-stage step up/down converters is presented. The system has been designed to regulate the supply current of a string of LEDs connected in series. The driver has the capability to maintain a constant luminous flux and to dimmer the LED in a wide range of current values. Simultaneously, the system maintains a very low level of current harmonics introduced into the AC mains. The analysis has demonstrated the feasibility in applying the sliding mode control for imposing simultaneously, at single-stage high-order converters (Ćuk, SEPIC and Shepard-Taylor), a Loss-Free Resistor (LFR) behavior and a regulated output current. In this context, it has been exposed in detail the dynamic analysis and the design of a current regulation loop for a Ćuk-based LFR supplied from a AC voltage source of 230 Vrms-50 Hz. One of the problems identified has been the presence of distortion in the input current waveform at the zero crossings. Such distortion prevents, for low input powers, the harmonics compliance and therefore limits their use in LED dimming. To overcome this problem, it has been proposed a technique, based on a variable hysteresis window, to improve the performance near the zero crossing of the input current. This improvement is achieved by increasing the switching frequency near this zero crossing region. With this technique, the dimming range goes from 0-100% maintaining at the same time very low harmonic distortion at the input current. Moreover, experimental and computer simulation results presented are given in order to verify the theoretical predictions.
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Folprecht, Martin. "Síťový spínaný zdroj." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-318189.
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Al, Tanany Ahmed. "A Study of Switched Mode Power Amplifiers using LDMOS." Thesis, University of Gävle, Department of Technology and Built Environment, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-701.
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This work focuses on different kinds of Switch Mode Power Amplifiers (SMPAs) using LDMOS technologies. It involves a literature study of different SMPA concepts. Choosing the suitable class that achieves the high efficiency was the base stone of this
work. A push-pull class J power amplifier (PA) was designed with an integrated LC resonator inside the package using the bondwires and die capacitances. Analysis and motivation of the chosen class is included. Designing the suitable Input/Output printed circuit board (PCB) external circuits (i.e.; BALUN circuit, Matching network and DC
bias network) was part of the work. This work is done by ADS simulation and showed a simulated result of about 70% drain efficiency for 34 W output power and 16 dB gain at 2.14 GHz. Study of the losses in each part of the design elements is also included.
Another design at lower frequency (i.e.; at 0.94 GHz) was also simulated and compared to the previous design. The drain efficiency was 83% for 32 W output power and 15.4 dB Gain.
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Yan, Xingda. "Hybrid modelling and control for switched-mode power converters." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/415789/.
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Switched-mode power converters are some of the most widely used power electronics circuits due to their advantages of high conversion efficiency, flexible output voltage, light weight. A variety of control methods have been developed for the switched-mode power converters. However, in many practical situation, additional constraints need to be considered, e.g., safety measurement, current limiting or soft-starting, gross changes of operation point with guaranteed system stability, which has not been fully addressed in the available research works. On the other hand, the majority of the control design for power converters are based on the state-space averaged approach which involves considerable approximation in analysis and synthesis. Hence, advanced control techniques are in demand, which should be more constraints friendly and based on more precise models. In this thesis, much attention has been spent on designing controllers for both DC-DC converters and DC-AC inverters based on hybrid modelling and Lyapunov stability theory. Due to the existence of the power switches, switched-mode power converters are hybrid systems with both continuous dynamics and discrete transition events. Instead of linearizing the converter model around a specific operating point, hybrid modelling captures both dynamics, which results in more accurate models. Firstly, a novel sampled-data control approach is proposed for DC-DC converters. DC-DC converters are modeled as sampled-data switched affine systems according to the status of the power switch. In order to avoid the delay of the switching signal, an on-line prediction method is adopted to estimate the system state at the next switching instant. Based on the switched affine model and the predicted system state, a novel switching control algorithm is synthesized by using the switched Lyapunov theory. The proposed approach is able to not only drive the output to a prescribed set point from any initial condition, but also track a varying reference signal, and the switching frequency can be adjusted online with guaranteed stability. In addition, with this approach, Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) operations can be treated in a unified way. Experimental verification has been carried out to test the effectiveness and merits of the proposed method. Furthermore, to compensate the information loss due to limited access to the state, a multiple sampling scheme is employed to derive a discrete-time switched affine model with an augmented measurement output for DC-DC converters. Based on the model, an output-feedback switching control law, which drives the system state to a set of attainable switched equilibria, is synthesized by using a quadratic state-space partition. The multiple sampling scheme not only facilitates the controller synthesis, but also improves the energy efficiency of the converter by allowing a lower switching frequency. In addition, hybrid modelling techniques have been extended to more complicated cases – DC-AC inverters as the increasing number of power switches and the time-variant nature of the references. A current controller based on the hybrid model of the three-phase two-level inverter has been developed, which can drive the inverter currents tracking the desired power references in realtime and keep a unity power factor at the same time. This method has been extended to three-phase NPC inverters later on. However, in order to solve the neutral point balancing issue, a capacitor voltages prediction algorithm, modified from model predictive control, has been adopted. It should also be mentioned that a novel hybrid model for a grid-connected single-phase NPC inverter also has been presented, which models not only the dynamic of the inverter but also the dynamic of the current reference. An experimental test platform including a three-phase NPC inverter and a FPGA control board has been designed to demonstrate the implementation of the proposed control scheme in practice.
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Johansson, Simon. "Design of power supplies for Piezo LEGS and SiC experiment : KTH Student satellite MIST." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-196216.
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KTH is funding a project whose goal is to send a satellite into space. This project is called MIST (Miniature Student Satellite) which is assembled by a team of students at KTH. On the satellite there are experiments that are invented by other teams, in two of those experiments a power supply is required. This thesis is a technical investigation on how to design the power supply to both of those experiments, which are called SiC and Piezo LEGS. Piezo LEGS will investigate how their nanosized motors will behave and function in a space environment. SiC will investigate how their silicone carbide transistors will be affected by the space environment. A team made of four other students was selected to produce SiC experiments and a PCB in which this work is included. A literature study was done to get a better understanding of how power supplies work and to know how to select a good power supply. When the power supplies were selected they were simulated to meet the requirements. The next step was to do a Printed Circuit Board(PCB) for the SiC experiment and Piezo LEGS to be able to test the power supplies functionality in the physical world. Both of the converters reached the required output and characteristics working on their respective PCB. More time is needed for long time testing and optimization on the PCB layouts.MIST (Miniature Student Satellite) är ett av KTH subventionerat projekt vilket har som mål att skicka upp en satellit i rymden. Projektet kommer omfatta flera olika experiment. Piezo LEGS ska undersöka en motors funktionalitet i rymdmiljö. SiC ska undersöka hur Silicon carbide halvledare och transistorer påverkas av rymdmiljön. Båda experimenten kräver varsin strömförsörjning för att fungera. Detta projekt ska undersöka kraven på strömförsörjning samt testa prototypen av ett kretskort för densamma. Först genomfördes en förstudie av de två typer av regulatorer som vanligtvis används som strömförsörjning, den linjära regulatorn och switch-mode regulatorn för att förklara olika strömförsörjningsteknologier, samt ta reda på de olika miljökraven. Baserat på förstudiens resultat erhölls kunskap för hur tester ska tas fram för funktionalitet av regulatorerna så att de når kraven för MIST för att sedan kunna producera de båda regulatorerna. Målet är att resultatet av simuleringarna på strömförsörjningen ska stämma överens med utfallet av kretskorten som produceras. Mätningar genomfördes på prototyp kretskort som visade att simuleringarna var korrekta och gav strömförsörjningen rätt resultat på kretskorten. Några av funktionerna på regulatorerna hann ej testas på grund av tidsbrist och mycket framtida arbete kvarstår.
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Parveg, Dristy Rahul. "A Study of Different Switched Mode Power Amplifiers for the Burst Mode Operation." Thesis, University of Gävle, Department of Technology and Built Environment, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-3090.
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Power-amplifier efficiency is a significant issue for the overall efficiency of most wireless system. Therefore, currently there are different kind of Switched mode power amplifiers are developed which are showing very high efficiency also at higher frequencies but all of these amplifiers are subjected to drive with the constant envelope signals. Whereas, for the increasing demand of high data rate transmissions in wireless communication there are some new modulation schemes are introduced and which are generating no more a constant envelope signal but a high peak to average power signal. Therefore, recently a new technique is proposed called the burst mode operation for operating the switched mode power amplifiers efficiently while driven by a high peak to average power signal.
The purpose of this master thesis work was to review the theory of this burst mode operation and some basic investigations of this theory on switched mode power amplifiers were performed in simulation environments. The amplifiers of class D, inverse D, DE and J are studied. The thesis work was mainly carried out by ADS and partly in MATLAB SIMULINK environment. Since this burst mode operation is a completely new technique therefore a new Harmonic balance simulation setups in ADS and Microwave Office are developed to generate the RF burst signals.
A Class J amplifier based on LDMOS technique is measured by a 16 carrier multi-tone signal having peak to average power ratio of 7 dB and achieved the drain efficiency of 50% with -30 dBc linearity at 946 MHz.
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Williams, Richard. "High frequency multi-element transformers for switched-mode power supplies." Thesis, University of Bristol, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283625.
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Theodore, Susan Mack 1958. "Reduction of electromagnetic interference in multiple switched mode power supplies." Thesis, The University of Arizona, 1995. http://hdl.handle.net/10150/278520.
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A method to reduce Electromagnetic Interference (EMI) of multiple switching waveforms by harmonic cancellation is presented. The waveforms considered are input currents generated by 'n' Discontinuous Mode (DCM) Flyback Switched Mode Power Supplies (SMPS) that share a common source. The waveforms are modeled as ideal triangular waveforms and a Fourier analysis is performed to determine the phase relationship, θ, that minimizes the EMI. The combined EMI is minimum when θ=360°/n and maximum when θ=0°. A system of two DCM Flyback SMPS is designed in such a way that both 0° and 180° phase shifts between input current waveforms are possible. In both cases EMI filters are designed to meet EMI standard MIL-STD-461. The system is simulated and constructed and the experimental results are presented. These results demonstrate the accuracy of the modeled waveform and the reduction of conducted EMI when optimal phasing is achieved.
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Hietakangas, S. (Simo). "Design methods and considerations of supply modulated switched RF power amplifiers." Doctoral thesis, Oulun yliopisto, 2012. http://urn.fi/urn:isbn:9789514298363.
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Abstract This thesis studies the design methods and properties of supply-modulated switch-mode radio frequency power amplifiers. Besides simulation based studies and theory review, two amplifiers were designed: a discrete MESFET class E amplifier (0.5 W at 1 GHz), and an integrated pHEMT class E-1 amplifier (2.0 W at 1.6 GHz) with an on-chip resonator. The existing design methods of the resonant output network of switching amplifiers were reviewed and some extensions on the handling of nonlinear capacitances were proposed. The effects of varying supply voltage were studied and suggestions were given to minimize Vdd / AM and Vdd / PM distortion in supply modulated amplifiers. The implementation of the bias feed was also discussed resulting in proposing a combination of a short transmission line and a small inductor, which provides both fast supply modulation and little effect on harmonic impedances. The main contributions are related to the study of the input impedance of a class E power amplifier, where the effects of supply dependent input impedance and timing skew generated by injected harmonic distortion were analyzed. The stabilization of the amplifier was also discussed. Based on the findings, a push-pull class E amplifier with extra cross-coupled feedback capacitors and second harmonic traps at the gates appears to be a very good starting point for a further studyTiivistelmä Tämä väitöstyö käsittelee radiotaajuuksilla toimivien käyttöjännitemoduloitujen kytkintehovahvistimien ominaisuuksia ja suunnittelumenetelmiä. Suunnittelumenetelmiin liittyvän katsauksen ja simulaatioihin perustuvan tutkimusten lisäksi kaksi vahvistinta toteutettiin väitöstutkimuksen aikana: diskreettikomponentein toteutettu E-luokan vahvistin (MESFET, 0.5 W ja 1 GHz) ja integroituna piirinä toteutettu käänteinen E-luokan vahvistin (pHEMT, 2.0 W ja 1.6 GHz), jonka lähdön resonaattoripiiri sisällytettiin integroituun piiriin. Kytkinvahvistimien suunnittelumenetelmiä verrattiin ja kehitettiin edelleen siten, että suunnitteluvaiheessa voidaan ottaa huomioon esim. transistoripiirin takaisinkytkennässä olevan kapasitanssin epälineaarisuus. Työssä tutkittiin myös käyttöjännitemodulaation vaikutusta kytkinvahvistimien toimintaan, ja tutkimuksen tuloksena annettiin muutamia ehdotuksia käyttöjänniteriippuvan amplitudi- (Vdd / AM) ja vaihemodulaation (Vdd / PM) vähentämiseksi. Lähdön biasointipiirin toteutukseen suositeltiin pienen kelan ja siirtolinjan yhdistelmää. Yhdistelmän avulla pyritään maksimoimaan modulaationopeus ja minimoimaan vaikutukset harmonisiin impedansseihin. Pääkohtina väitöksessä ovat E-luokan kytkinvahvistimesta saadut tutkimus- ja mittaushavainnot käyttöjännitteen funktiona muuttuvasta transistorin tuloimpedanssista sekä suurikokoisen transistorin tuloissa tapahtuvan, säröytymisen aiheuttaman tulosignaalien ajoitusvirheen analyysi. Näiden lisäksi vahvistimen stabiilisuuteen kiinnitettiin huomiota. Saatujen havaintojen perusteella voimme todeta, että push-pull -tyyppinen E-luokan vahvistin olisi mielenkiintoinen valinta jatkotutkimuksille
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Bowden, James Anthony. "Electrical tuning of electromagnetic energy harvesters with switched mode power electronics." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616884.
Full textAbstract:
Energy Harvesting is a key enabling technology for highly distributed electronic systems such as wireless sensor networks, One of the most commonly described harvesting techniques is vibration harvesting, where a base-excited resonant mass/spring system is damped via an electromechanical transducer. A significant drawback of the resonant mechanical system, required to amplify low-level base vibrations, is the narrow bandwidth over which the system can operate, This thesis describes work carried out towards a method of increasing the bandwidth of resonant vibration harvesters by synthesising a variable complex load impedance using highly efficient switched-mode converters: loading the harvester with an optimum complex impedance effectively tunes the complete electromechanical system to the excitation frequency. This tuning effect is described analytically and demonstrated in practice with linear impedance emulating circuits. To benchmark the electrically tuned system against a more conventional converter, a micro power resistance emulator was developed, featuring an average quiescent power consumption of 56.6uW and a peak efficiency of 85.4%. The prototype harvester for which this tuning system was developed generates approximately 20mW, presenting a challenge for • converter design. This is further exacerbated when synthesizing large reactive loads at tuning frequencies far from mechanical resonance where the apparent power is much larger than the real power delivered from the harvester. To achieve the desired performance a custom micropower VSC power stage was implemented using discrete components, having an average quiescent power consumption of 454uW. The complete switched-mode tuning system requires current and voltage sensing, control compensation and PWM generation. A range of analogue and miJ5'ed signal implementations of these subsystems were investigated and it was concluded that at this power level the most significant challenge arises from balancing gate drive losses against the requirement for ultra low conduction losses in the power devices. Experimental results demonstrate that electrical tuning can extend the bandwidth over which a resonant vibration harvester can provide useful DC power, to almost three times that achieved with a simple unity power factor converter synthesising a fixed load resistance.
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Pešl, Jiří. "Spínaný zdroj se spínáním při nulovém napětí." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242009.
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Diploma thesis describes the design of an switched mode power supply with switching at zero voltage for driving the anode of Anode-layer type ion source. First aim of thesis is ion sources and specialy Anode-layer type of ion source in detail. Main aim of thesis are important aspects of the design of switching mode power supply, which comes later the detailed construction of an switched mode power supply with output voltage 2800 V at output power 2800 W.
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Li, Nan. "Digital control strategies for DC/DC SEPIC converters towards integration." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00760064.
Full textAbstract:
The use of SMPS (Switched mode power supply) in embedded systems is continuously increasing. The technological requirements of these systems include simultaneously a very good voltage regulation and a strong compactness of components. SEPIC ( Single-Ended Primary Inductor Converter) is a DC/DC switching converter which possesses several advantages with regard to the other classical converters. Due to the difficulty in control of its 4th-order and non linear property, it is still not well-exploited. The objective of this work is the development of successful strategies of control for a SEPIC converter on one hand and on the other hand the effective implementation of the control algorithm developed for embedded applications (FPGA, ASIC) where the constraints of Silicon surface and the loss reduction factor are important. To do it, two non linear controls and two observers of states and load have been studied: a control and an observer based on the principle of sliding mode, a deadbeat predictive control and an Extended Kalman observer. The implementation of both control laws and the Extended Kalman observer are implemented in FPGA. An 11-bit digital PWM has been developed by combining a 4-bit Δ-Σ modulation, a 4-bit segmented DCM (Digital Clock Management) phase-shift and a 3-bit counter-comparator. All the proposed approaches are experimentally validated and constitute a good base for the integration of embedded switching mode converters
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Goad, Stephen D. "The theory and design of switched-mode power transformers for minimum conductor loss." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/52290.
Full textAbstract:
A comprehensive and general analysis of the electromagnetic
fields, power dissipation, and energy storage
within transformer windings is presented. Emphasis is
placed on applications in switched-mode power conversion.
One-dimensional radial variation of the field quantities is
assumed.
The first phase of the investigation is for sinusoidal
excitation; solutions for the current density and magnetic
field intensity are derived and studied in order to develop
a fundamental understanding of the basic phenomena.
Expressions for the power dissipation and energy storage in
both single- and multi-layer windings are then derived
which, upon investigation, yield a technique for minimizing
the power dissipation by choosing an optimum conductor
thickness. Several levels of accuracy, ranging from exact
solutions to very simple and physically meaningful series
approximations, are defined and examined to determine their
usefulness and range of validity.
The time-harmonic treatment is generalized to arbitrary
periodic exoitation by means of Fourier analysis, resulting
in a powerful extension of its applicability to any possible
converter topology. Results for several representative
waveshapes are presented from which a fundamental dependence
cn the waveform bandwidth is discovered.
Practical application of the theoretical analysis is
considered by developing models for several couon winding
types: single and multi-filar round wire, litz wire, and
sheet conductors. Experimental results are presented and
compared with the theoretical results for each of these
cases. Finally, a design procedure is outlined for
switched—mode pour transformers which is based on this
work.Ph. D.
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Garcia, Robert John. "THE EFFECTS OF COMPENSATION ON LOAD TRANSIENT RESPONSE IN SWITCHED MODE POWER CONVERTERS." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/291724.
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Tsang, Chi Wa. "Novel design techniques and control schemes for higher efficiency switched-mode power converters." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6476/.
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This thesis details novel control schemes and design techniques with the aim of improving the performance of several switched-mode power converter topologies. These improvements include higher steady-state and transient efficiencies for hard-switching converters and the automatic current limiting provision for LLC resonant converters. The thesis initially attempts to use linear closed-loop controllers to improve the transient response of synchronous buck converters, enabling them to be designed with a lower open-loop bandwidth so that the system can achieve higher efficiency. Three types of controllers were investigated viz: the PID, the state-feedback and the predictive controller. All three controllers exhibit similar step responses, which are the maximum transient responses achievable by the linear controllers with the given requirements. The thesis then examines the parallel converter (i.e. a converter with two parallel connected power modules (PMs)) in detail with a view to improve the efficiency and to minimise the current ripple experienced by the output capacitor. Two control schemes and a design technique for the parallel converter are proposed, to simultaneously improve its efficiency and power density. The parallel converter in this research consists of two non-identical rated PMs (termed main PM and auxiliary PM), with the transient response requirement allocated to the auxiliary PM, thereby allowing the main PM to operate at a lower frequency for higher steady-state efficiency. The first control scheme activates the auxiliary PM only when a pre-determined deviation in load/output voltage is exceeded under a load step. Thus, eliminating the losses contributed by the low efficiency auxiliary PM for small load step changes. The second control scheme shapes the auxiliary PM inductor current to be equal and opposite to the main PM current ripple, which when combined reduce the current ripple as experienced by the output filter capacitor, thereby allowing a lower value (and hence physically smaller) capacitor to be selected for higher power density. In order to improve the converter's steady-state efficiency further, the minimum load condition is allocated to the auxiliary PM in the new design technique. These allow both the main PM inductance and its switching frequency to be lower for higher efficiency. In recent years, the LLC has received much attention owing to its favourable operating characteristics including high efficiency and high power density. Usually one chooses to operate at or very close to the load independent point (LIP) since very little control effort is required to regulate the converter's output voltage in response to changes in the load. However under fault conditions where the load tends towards a short circuit, excessive currents can flow and thus control action need to be taken to protect both the converter and the load. The final topic of the thesis hence studies the characteristics of an LLC resonant converter with current-limiting capacitor-diode clamp and develops a new equivalent circuit model to predict the behaviour under overload conditions. A detailed analysis of the converter is presented using the proposed model, from which a design methodology is derived allowing the optimum circuit components to be selected to achieve the required current limiting/protection characteristics.