Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: Conventional Voltage Regulators.
Artykuły w czasopismach na temat „Conventional Voltage Regulators”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 50 najlepszych artykułów w czasopismach naukowych na temat „Conventional Voltage Regulators”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj artykuły w czasopismach z różnych dziedzin i twórz odpowiednie bibliografie.
1
Akkouchi, K., L. Rahmani i R. Lebied. "New application of artificial neural network-based direct power control for permanent magnet synchronous generator". Electrical Engineering & Electromechanics, nr 6 (3.12.2021): 18–24. http://dx.doi.org/10.20998/2074-272x.2021.6.03.
Pełny tekst źródłaStreszczenie:
Purpose. This article proposes a new strategy for Direct Power Control (DPC) based on the use of Artificial Neural Networks (ANN-DPC). The proposed ANN-DPC scheme is based on the replacement of PI and hysteresis regulators by neural regulators. Simulation results for a 1 kW system are provided to demonstrate the efficiency and robustness of the proposed control strategy during variations in active and reactive power and in DC bus voltage. Methodology. Our strategy is based on direct control of instant active and reactive powers. The voltage regulator and hysteresis are replaced by more efficient and robust artificial neuron networks. The proposed control technique strategy is validated using MATLAB / Simulink software to analysis the working performances. Results. The results obtained clearly show that neuronal regulators have good dynamic performances compared to conventional regulators (minimum response time, without overshoots). Originality. Regulation of continuous bus voltage and sinusoidal currents on the network side by using artificial neuron networks. Practical value. The work concerns the comparative study and the application of DPC based on ANN techniques to achieve a good performance control system of the permanent magnet synchronous generator. This article presents a comparative study between the conventional DPC control and the ANN-DPC control. The first strategy based on the use of a PI controller for the control of the continuous bus voltage and hysteresis regulators for the instantaneous powers control. In the second technique, the PI and hysteresis regulators are replaced by more efficient neuronal controllers more robust for the system parameters variation. The study is validated by the simulation results based on MATLAB / Simulink software.
2
de Negreiros, Gustavo Fernandes, Fábio Xavier Lobo, Igor Cavalcante Torres i Chigueru Tiba. "Impact on Voltage Regulation in Medium Voltage Distribution Networks Due to the Insertion of Photovoltaic Generators". Energies 16, nr 3 (26.01.2023): 1307. http://dx.doi.org/10.3390/en16031307.
Pełny tekst źródłaStreszczenie:
The objective of this paper was to analyze the impacts caused by the operation of voltage regulators in electrical distribution networks and to evidence the number of operations in the face of short-duration voltage variation caused by the high intermittency of the connected PV generators. A real LV and MV feeder was used, modeled in OpenDSS software, based on normative standards, adjustments, and technical maneuvers strategically used by the local utility. The analyses considered the temporal variations for the photovoltaic generators and different load demand profiles connected to the feeder. The feeder was submitted to the demand curves varying the load percentage, framing it in high and conventional (nominal) load according to the profiles of consumers and prosumers connected. The simulations made it possible to observe the exacerbated elevation in the number of maneuvers performed by the voltage regulators of the network. The single-phase voltage regulators stood out by the elevation of control operations, causing premature wear of the PV generation equipment connected to the most loaded phase. It was observed that discrepancies in the power flow in the lines and the voltage levels at the busbars. The creation of strategies and decisions to correct these impacts caused to transformers and regulators is possible.
3
Ameziane, Hatim, Kamal Zared, Hicham Akhamal i Hassan Qjidaa. "Full On-chip low dropout voltage regulator with an enhanced transient response for low power systems". International Journal of Electrical and Computer Engineering (IJECE) 9, nr 6 (1.12.2019): 4637. http://dx.doi.org/10.11591/ijece.v9i6.pp4637-4648.
Pełny tekst źródłaStreszczenie:
<span>A full on chip low Dropout Voltage Regulator (LDO) with fast transient response and small capacitor compensation circuit is proposed. The novel technique is implemented to detect the variation voltage at the output of LDO and enable the proposed fast detector amplifier (FDA) to improve load transient response of 50mA load step. The large external capacitor used in Conventional LDO Regulators is removed allowing for greater power system integration for system-on-chip (SoC) applications. The 1.6-V Full On-Chip LDO voltage regulator with a power supply of 1.8 V was designed and simulated in the 0.18µm CMOS technology, consuming only 14 µA of ground current with a fast settling-time LNR(Line Regulation) and LOR(Load regulation) of 928ns and 883ns respectively while the rise and fall times in LNR and LOR is 500ns.</span>
4
Ali Azam Khan, Md, i Mohammad Ali Choudhury. "Efficient Voltage Regulation with Modified Hybrid SEPIC DC-DC-Converter". MATEC Web of Conferences 160 (2018): 02004. http://dx.doi.org/10.1051/matecconf/201816002004.
Pełny tekst źródłaStreszczenie:
Switch mode dc-dc converters are attractive for their small size, ease of control and efficient power conversion. Output voltage is regulated by duty cycle control of semiconductor switch of switch mode dc-dc converters. The voltage gain and efficiency of practical switching regulators deviate from ideal values at extreme duty cycles. Also, desired gain /attenuation is not achievable at high/low duty cycles. In applications where high gain or high attenuation of voltage is desired with acceptable energy conversion efficiency, hybrid dc-dc switching converters are used. Hybrid dc-dc converters are combination of voltage multiplier/division circuit with appropriate SMPS circuits. By incorporating voltage multiplier/division cell with conventional SEPIC converters, desired voltage gain (either very low or very high) may be achieved at acceptable energy conversion efficiency. In the present work with an aim to attain very high voltage gain by conventional SEPIC topologies, a new voltage multiplier cell consisting of multiple inductors and diodes is proposed.
5
Bulatov, Yuri, Andrey Kryukov i Konstantin Suslov. "Using Group Predictive Voltage and Frequency Regulators of Distributed Generation Plants in Cyber-Physical Power Supply Systems". Energies 15, nr 4 (9.02.2022): 1253. http://dx.doi.org/10.3390/en15041253.
Pełny tekst źródłaStreszczenie:
The widespread use of distributed generation (DG) plants in cyber-physical power supply systems (CPPSS) requires solving the complex problem of setting their regulators. The presented study aimed to determine the performance of the group predictive voltage and frequency regulators of DG plants in CPPSS. These studies were conducted in the MatLab environment on the CPPSS models with gas turbine units and with a small-scale hydroelectric power plant. The proposed method for tuning group predictive regulators makes it possible to improve the quality control indices. The research has established that with an additional load connected, the maximum voltage dip is reduced by a factor of 3.5 compared to conventional control regulators. In addition, the time of a transient process for the generator rotor speed is decreased by a factor of 3. In the case of a short-term short circuit, predictive regulators can reduce the time of the transient process by a factor of 1.5 and the overshoot by more than 2 times. The simulation results have confirmed the efficiency of group predictive regulators when used in DG plants, i.e., improvement of the quality of control processes in various operating modes.
6
Mayouf, Messaoud. "Control strategy of a standalone variable speed wind energy conversion system based on direct drive permanent magnet synchronous generator". Journal of Renewable Energy and Technology 1, nr 1 (11.11.2022): 1–8. http://dx.doi.org/10.38208/jret.v1i1.378.
Pełny tekst źródłaStreszczenie:
In this paper, we propose a control strategy for a stand-alone wind energy conversion system (WECS) based on a direct drive permanent magnet synchronous generator (PMSG), loaded on a DC-type charge. In the considered wind-power generating system, the generator provides a DC voltage to the load through a three-phase rectifier, controlled by the Pulse Width Modulation (PWM) technique. The main control strategy target is to maintain the DC voltage insensitive to fast changes in wind speed and load, by offsetting the generator output current with the charge current. The approach adopted in this paper is based on the estimate of the PMSG electromagnetic torque assuming that wind velocity remains quasi-stationary in a steady state. The instant power reference is assessed by the charge controller according to the rated DC bus voltage, using actual electrical measurements as the voltage and current. To achieve adequately the power decoupling, the field-oriented control is used with conventional PI-type regulators to provide direct and quadrature control reference voltages and ensure DC bus voltage regulation. To assess the proposed control strategy efficiency, the simulation model was subjected to different load and wind speed variations. Simulation results performed using the MATLAB Simulink model show high accuracy and strength during steady-state and transient operations.
7
Ghazzali, Mohamed, Mohamed Haloua i Fouad Giri. "Fixed-time control of voltage dynamics of three-phase voltage source inverters with LC output filter". International Journal of Power Electronics and Drive Systems (IJPEDS) 13, nr 3 (1.09.2022): 1843. http://dx.doi.org/10.11591/ijpeds.v13.i3.pp1843-1853.
Pełny tekst źródłaStreszczenie:
<p>This paper puts forward a fixed-time cascade voltage control system for threephase voltage source inverters (VSIs) with LC output filter.First, a feedforward decoupling mechanism is used to elminate the dependency between the d-q parts of the control system. Then, proportional-integral (PI) regulators are used for current control in the inner loop. The current reference is provided by a novel VSI control technique developed for fixed-time voltage regulation and reference tracking. The approach suggested in this work tracks and maintains the voltage magnitude at its normalized value in a finite-time and before a maximum settling-time fixed in advance and independent of the system’s initial state. The voltage controller also maintains current stability by providing a smoother and smaller current reference. A comparative study with VSI conventional PI control for linear, nonlinear and unbalanced loads confirms the theoretical results.</p>
8
Djebbar, Mohamed Salah, Aziz Boukadoum i Abla Bouguerne. "Performances of a wind power system based on the doubly fed induction generator controlled by a multi-level inverter". International Journal of Power Electronics and Drive Systems (IJPEDS) 14, nr 1 (1.03.2023): 100. http://dx.doi.org/10.11591/ijpeds.v14.i1.pp100-110.
Pełny tekst źródłaStreszczenie:
The objective of this work is to study the contribution that the use of the multi-level inverter can make compared to a conventional two-level inverter, in a wind power production line (WPG) associated with a doubly fed induction generator (DFIG). The DFIG is driven by a variable speed wind turbine and operates in maximum power point tracking (MPPT) mode, for optimum efficiency. The rotor of the DFIG is supplied by a DC/AC inverter with five levels with MPC structure, controlled by the PWM technique, while the stator is connected with the network. The active and reactive powers exchanged between the DFIG and the network is achieved by indirect vector control with oriented stator flux (IFOC), with conventional regulators, ensuring zero reactive power and a unitary power factor. The total harmonic distortion (THD) of the current signals/voltages of the entire wind chain is exposed and criticized. The obtained results are very promising, offering the possibility for wind turbines with multi-level inverter to work in high voltage and large power.
9
Xu, Aoqi, Yassine Bouteraa, Nasreen Kausar, Ardashir Mohammadzadeh, Dragan Pamucar i Mohammed Abdullah Salman. "A Fuzzy Intelligent Computing Approach for Energy/Voltage Control of Microgrids". Journal of Mathematics 2023 (17.04.2023): 1–11. http://dx.doi.org/10.1155/2023/5289114.
Pełny tekst źródłaStreszczenie:
The control and energy management problems of microgrids (MGs) are challenging due to the high level of uncertainties and disturbances such as changes in demands, mechanical powers, and solar energies. So, intelligent computing is needed to be developed for these systems. This paper uses an optimal and robust fuzzy controller for automatic voltage and frequency regulation. The fuzzy logic develops the resistance against uncertainties and disturbances such as irradiation, wind power changes, and load demand variation. The introduced controller uses appropriate and effective criteria that include rising time, settling time, overshoot, and the degree of resistance of the control system to uncertainties and perturbation effects. Through simulations and compassion with conventional regulators, the better accuracy of the suggested approach is demonstrated.
10
Abegaz, Brook W., i Sina Zarrabian. "Modified Q-Learning Method for Automatic Voltage Regulation in Wide-Area Multigeneration Systems". International Transactions on Electrical Energy Systems 2022 (10.06.2022): 1–13. http://dx.doi.org/10.1155/2022/3047761.
Pełny tekst źródłaStreszczenie:
The state-estimation and optimal control of multigeneration systems are challenging for wide-area systems having numerous distributed automatic voltage regulators (AVR). This paper proposes a modified Q-learning method and algorithm that aim to improve the convergence of the approach and enhance the dynamic response and stability of the terminal voltage of multiple generators in the experimental Western System Coordinating Council (WSCC) and large-scale IEEE 39-bus test systems. The large-scale experimental testbed consists of a six-area, 39-bus system having ten generators that are connected to ten AVRs. The implementation shows promising results in providing stable terminal voltage profiles and other system parameters across a wide range of AVR systems under different test scenarios including N-1 contingency and fault conditions. The approach could provide significant stability improvement for wide-area systems as compared to the implementation of conventional methods such as using standalone AVR and/or power system stabilizers (PSS) for the wide-area control of power systems.
11
Go, Seok-Il, Sang-Yun Yun, Seon-Ju Ahn, Hyun-Woo Kim i Joon-Ho Choi. "Heuristic Coordinated Voltage Control Schemes in Distribution Network with Distributed Generations". Energies 13, nr 11 (3.06.2020): 2849. http://dx.doi.org/10.3390/en13112849.
Pełny tekst źródłaStreszczenie:
The voltage and reactive power control (Volt/VAR Control, VVC) in distribution networks has become a challenging issue with the increasing utilization of distributed generations (DGs). In this paper, a heuristic-based coordinated voltage control scheme that considers distribution voltage control devices, i.e., on-load tap changers (OLTC) and step voltage regulators (SVR), as well as reactive power control devices, i.e., DGs, are proposed. Conventional voltage control methods using non-linear node voltage equations require complex computation. In this paper, the formulation of simplified node voltage equations accounting for changes in tap position of distribution voltage control devices and reactive power changes of reactive power control devices are presented. A heuristic coordinated voltage control scheme using the proposed simplified node voltage equations is proposed. A coordinated voltage control scheme to achieve voltage control for nominal voltage and conservative voltage reduction (CVR) is presented. The results of the proposed schemes are compared with the results from the quadratic optimization method to confirm that the proposed schemes yields suitably similar results. Furthermore, a tap scheduling method is proposed to reduce the number of tap changes while controlling network voltage. The tap position is readjusted using a voltage control performance index (PI). Simulation results confirm that when using this method the number of tap changes is reduced. The proposed scheme not only produces reasonable performance in terms of control voltage of networks but also reduces the number of tap changes made by OLTC. The proposed control method is an alternative candidate for a system to be applied to practical distribution networks due to its simplified calculations and robust performance.
12
Boudechiche, Ghania, Mustapha Sarra, Oualid Aissa, Jean-Paul Gaubert, Boualam Benlahbib i Abderezak Lashab. "Anti-Windup FOPID-Based DPC for SAPF Interconnected to a PV System Tuned Using PSO Algorithm". European Journal of Electrical Engineering 22, nr 4-5 (30.10.2020): 313–24. http://dx.doi.org/10.18280/ejee.224-503.
Pełny tekst źródłaStreszczenie:
This paper deals with a shunt active power filter (SAPF) integrated in a photovoltaic (PV) system, which is interfaced to the grid via a double-stage configuration, for simultaneously improving the power quality in the existence of non-linear loads and injecting the PV harvested power to the power grid. The direct power control (DPC) based on the conventional Proportional-integral (PI) suffers from some shortcomings in the transient state, such as large overshoots and undershoots in the voltage. Long response time is another disadvantage when using such a controller. To overcome this situation, the proposed control method is equipped by an anti windup fractional order proportional-integral differentiator (AW-FOPID) regulator, replacing the standard PI or PID regulators to maintain the DC link voltage at its desired value with small overshoots and undershoots in the voltage, while maintaining a short response time. The AW-FOPID controller, however, has five parameters, which makes it troublesome to tune. Accordingly, to adjust this AW-FOPID parameters, the Particle Swarm Optimization (PSO) algorithm is employed by minimizing the Integral Time Absolute Error (ITAE). Furthermore, an intelligent algorithm for tracking the maximum power point (MPPT) based on fuzzy logic has been applied to eventually resolve the drawback of the rapidly changing weather conditions. The overall control scheme is examined by simulation using MATLAB/Simulink software. The obtained simulation results and comparative study demonstrate the feasibility and performance of this control strategy.
13
Zhang, Jun Li. "STATCOM Based on Cascade Multilevel Inverter". Applied Mechanics and Materials 55-57 (maj 2011): 1365–69. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.1365.
Pełny tekst źródłaStreszczenie:
Static Synchronous Compensator (STATCOM) using the voltage source inverter (VSI) has been widely accepted as the current generation of the reactive power regulators of power system, improving the network steady-state and dynamic performances, regulates power factor, reduces losses and allows higher power flows in the exist line, assists in the post-fault recovery of transmission system. The cascade inverter not only can eliminate the bulky transformers compared with the conventional STATCOM, but also employ a sinusoid pulse width modular scheme: phase-shift. The use of the feedback linearization approach to design nonlinear controllers of power inverters is particularly interesting because it transforms a nonlinear system into a linear one in terms of its input–output relationship. Partial linearization may still be useful in some cases providing that the internal zero dynamics exhibit a proper transient performance.
14
Guesmi, Tawfik, Badr M. Alshammari, Yosra Welhazi, Hsan Hadj Abdallah i Ahmed Toumi. "Robust Fuzzy Control for Uncertain Nonlinear Power Systems". Mathematics 10, nr 9 (27.04.2022): 1463. http://dx.doi.org/10.3390/math10091463.
Pełny tekst źródłaStreszczenie:
This paper presents a new control technique based on uncertain fuzzy models for handling uncertainties in nonlinear dynamic systems. This approach is applied for the stabilization of a multimachine power system subject to disturbances. In this case, a state-feedback controller based on parallel distributed compensation (PDC) is applied for the stabilization of the fuzzy system, where the design of control laws is based on the Lyapunov function method and the stability conditions are solved using a linear matrix inequalities (LMI)-based framework. Due to the high number of system nonlinearities, two steps are followed to reduce the number of fuzzy rules. Firstly, the power network is subdivided into sub-systems using Thevenin’s theorem. Actually, each sub-system corresponds to a generator which is in series with the Thevenin equivalent as seen from this generator. This means that the number of sub-systems is equal to the number of system generators. Secondly, the significances of the nonlinearities of the sub-systems are ranked based on their limits and range of variation. Then, nonlinearities with non-significant variations are assumed to be uncertainties. The proposed strategy is tested on the Western systems coordinating council (WSCC) integrated with a wind turbine. The disturbances are assumed to be sudden variations in wind power output. The effectiveness of the suggested fuzzy controller is compared with conventional regulators, such as an automatic voltage regulator (AVR) and power system stabilizers (PSS).
15
Dev Prakash Chourasia and Bhoopendra Singh. "Hybrid Electric Vehicle with Solar Integration using Bi directional DC-DC converter with Fuzzy Logic Control". International Journal for Modern Trends in Science and Technology, nr 02 (12.02.2021): 1–8. http://dx.doi.org/10.46501/ijmtst0702001.
Pełny tekst źródłaStreszczenie:
In this paper, a sunlight-based hybrid electric vehicle is planned on MATLAB Simulink. In this a primary fuel source which sun based and a helper source which is battery is utilized to fabricate a bidirectional DC-DC converter. In General thought, an electric vehicle uses a battery that is charged from an external force gracefully, anyway sunlight-based PV modules are used to charge a battery by strategies for fascinating radiation from the sun and changing over it into electrical force (Photovoltaic Effect) by proposed procedure. The electrical capacity to batteries got from sun powered PV modules, which might be connected either in course of action or equivalent and charge regulators. To cross a conclusive force point in the sunlight-based board, additionally Maximum Power Point Tracker (MPPT) regulator is used [3]. The sun powered PV part is executed utilizing a fuzzy based MPPT strategy. In the control framework for bidirectional DC-DC converter, an ANFIS framework is utilized to diminish the blunders and give a DC yield to DC machine which speaks to the Electric Vehicle. The utilization of Solar gives limitless energy and diminishes the expense of different other options. The advantage of ANFIS and Fuzzy joined framework gives the best accuracies and proficiency in the framework as contrasted and conventional PI based which is a more calculative control framework. The yield voltage of bidirectional DC-DC converter is about 430v to drive the electric vehicle. The advantage of this plan is low count intricacy by utilizing ANFIS and Fuzzy based MPPT calculation for Photovoltaic module[3].
16
Mikhalchuk, Nikolay. "PERSPECTIVE DIRECTIONS FOR THE IMPROVEMENT OF ENERGYOPTIMAL PARAMETERS AND TRACTION PROPERTIES OF THE LOCOMOTIVE". Bulletin of scientific research results, nr 4 (17.12.2017): 161–73. http://dx.doi.org/10.20295/2223-9987-2017-4-161-173.
Pełny tekst źródłaStreszczenie:
Objective: To develop and justify energy-efficient and energy-saving control technology of traction electric drive with maximum realization of traction properties. Methods: Mathematical modeling, experimental manufacturing of prototypes of the converters and control system. Results: Theoretical justification was presented, based on refinement of the theory of energy processes in electrical circuits with solid state power controllers. It was proposed to apply electrical resistance of elements in electric power systems as a power control parameter instead of the conventional voltage. It was revealed that, in contrast to the existing analogues, semiconductor power regulators of different application with a new control parameter acquire the property of the electric variator. Technical solutions for manufacturing an innovative traction electric rolling stock were introduced with the use of advanced technical solutions of power control with adaptive control system that provides improved traction properties without shortening irreversible transformation of electric energy of power semiconductor devices. As an example, the solutions involving artificial intelligence in control systems of complex technical systems were presented, based on graphics processors, neural networks, providing parallel processing of large information arrays. Practical importance: Introduction of electric solid state variable speed with adaptive, intelligent control systems will significantly raise energy efficiency and improve the implementation of traction parameters of the locomotive.
17
Opeiko, O. F. "Reference Input Signals Formation for Induction Motor Control in Traction Drive". ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations 66, nr 3 (1.06.2023): 205–14. http://dx.doi.org/10.21122/1029-7448-2023-66-3-205-214.
Pełny tekst źródłaStreszczenie:
The purpose of this work is to build the analytical improved (with resistances estimation) real time computation of the reference inputs for rotor flux and torque in the vector control system of an induction motor of a traction electric drive. The reference inputs must maximize electromagnetic torque in conditions of voltage source instability, particularly in magnetic field weakening mode. The conventional way to control the field weakening mode is to form flux coupling task inversely proportional to the speed or inversely proportional to the square of the speed in second and third zones respectively. Such reference input signals are not able to provide the maximum torque capability over the entire speed range, and the improved torque capability is achieved in different ways. For instance, voltage feedback is useful for the torque capability enhancement in conditions of internal and external perturbations. A wide change in speed with the weakening of the flux reveals the nonlinear properties of an induction electric motor. However, in vector control systems, proportional-integrating (PI) regulators are usually used. Therefore, firstly, linear PI controllers must be robust, and secondly, the reference input signals for flux and torque must guaranty linear, not saturated state of each PI controller. The proposed expressions for calculating reference inputs for induction motor rotor flux and electromagnetic torque as functions of actual rotor speed are the approximate expressions. The estimation of the possible error shows that the error is acceptable. Simulation is performed for the vector control system of an induction motor and taking into account the calculation of the control signal by the microcontroller and the dynamics of the frequency invertor. The simulation of the resulting system validates the effectiveness of the control system using the proposed expressions for the formation of real-time reference input signals for setting the flux and torque.
18
Reddy, R. Obulakonda, Sandeep Kautish, V. Padmanabha Reddy, N. Sudhakar Yadav, Meznah M. Alanazi i Ali Wagdy Mohamed. "Effects of Integrated Fuzzy Logic PID Controller on Satellite Antenna Tracking System". Computational Intelligence and Neuroscience 2022 (7.03.2022): 1–11. http://dx.doi.org/10.1155/2022/7417298.
Pełny tekst źródłaStreszczenie:
An electrical device that transforms the electricity into the waves of radio and vice versa is termed the antenna. Its main deployment is in the transmitter and receiver of the antenna. While transmission, the transmitter of radio at the extremities of the antenna furnishes the electricity which oscillates at the frequency of radio wave and energy is released as current as em waves. Some of the voltage is formed from the em wave that is invaded at the point of receiving to amplify the receiver. This study focuses on the analysis of the satellite system to aid in mobile antenna tracking. It also examines the techniques for fuzzy control which make up traditional networks that are used. Initially, a basic idea of tracking loops with stabilized antennas was suggested in light of the requirement for the margin of phase and bandwidth. If the gain of the track is reduced due to changes in attributes and throughput, it will be reduced. In addition, fuzzy regulators and PID constituents are used to enhance the loop. The results indicate that the higher and lower antenna tracking gains within the loop were the best fit and the loop's fluctuations are reduced. A controller based on fuzzy logic can be most efficient due to its simplicity and robustness. It is also discovered that fuzzy logic controllers are evaluated by their behavior in relation. This paper presents an evaluation of the controllers in fuzzy logic, which is based on its integration with conventional controllers. There are three gains in PID's regulator PID and every gain can be used to control the variables of inputs and outcomes. The effects of the responses were analyzed and were compared. The commonality was discovered in the results according to the increase in time for II/6 and II/3 based on PID's regulator PID stability, it can be improved by this system, and there is a reduction in the duration of stability. Furthermore, the period of stability may be reduced through the fusion of PID and fuzzy. The effectiveness of the system could be enhanced by the implementation of the neural network. It is also possible to design the two types of control that could be used to control the proposed solid platform.
19
Malysz, John, Serge A. Y. Afeli, Aaron Provence i Georgi V. Petkov. "Ethanol-mediated relaxation of guinea pig urinary bladder smooth muscle: involvement of BK and L-type Ca2+ channels". American Journal of Physiology-Cell Physiology 306, nr 1 (1.01.2014): C45—C58. http://dx.doi.org/10.1152/ajpcell.00047.2013.
Pełny tekst źródłaStreszczenie:
Mechanisms underlying ethanol (EtOH)-induced detrusor smooth muscle (DSM) relaxation and increased urinary bladder capacity remain unknown. We investigated whether the large conductance Ca2+-activated K+ (BK) channels or L-type voltage-dependent Ca2+ channels (VDCCs), major regulators of DSM excitability and contractility, are targets for EtOH by patch-clamp electrophysiology (conventional and perforated whole cell and excised patch single channel) and isometric tension recordings using guinea pig DSM cells and isolated tissue strips, respectively. EtOH at 0.3% vol/vol (∼50 mM) enhanced whole cell BK currents at +30 mV and above, determined by the selective BK channel blocker paxilline. In excised patches recorded at +40 mV and ∼300 nM intracellular Ca2+ concentration ([Ca2+]), EtOH (0.1–0.3%) affected single BK channels (mean conductance ∼210 pS and blocked by paxilline) by increasing the open channel probability, number of open channel events, and open dwell-time constants. The amplitude of single BK channel currents and unitary conductance were not altered by EtOH. Conversely, at ∼10 μM but not ∼2 μM intracellular [Ca2+], EtOH (0.3%) decreased the single BK channel activity. EtOH (0.3%) affected transient BK currents (TBKCs) by either increasing frequency or decreasing amplitude, depending on the basal level of TBKC frequency. In isolated DSM strips, EtOH (0.1–1%) reduced the amplitude and muscle force of spontaneous phasic contractions. The EtOH-induced DSM relaxation, except at 1%, was attenuated by paxilline. EtOH (1%) inhibited L-type VDCC currents in DSM cells. In summary, we reveal the involvement of BK channels and L-type VDCCs in mediating EtOH-induced urinary bladder relaxation accommodating alcohol-induced diuresis.
20
Alelaj, Fajer, Mohamed Dahidah i Haris Patsios. "Mitigating Electrical Disturbances with Hybrid Distribution Transformer". Electrical Engineering : An International Journal 10, nr 1 (30.03.2023): 1–15. http://dx.doi.org/10.5121/eeij.2023.10101.
Pełny tekst źródłaStreszczenie:
Hybrid transformers (HT) have the advantages of the conventional transformer, the regulatory abilities of power electronic converters, and reduce the impact of the grid. The impacts of the existing grid are voltage sag, voltage swell, harmonic distortion, and voltage unbalanced. The power electronic converter has a controllable advantage such as regulating the voltage and can transfer only a fraction of the power. The aim of the paper is to augment the conventional power distribution transformer with a partially rated power electronic module to enhance flexibility and introduce new features to the distribution transformer. In this paper, the proposed back-to-back converter included an active front rectifier and a modular multilevel converter (MMC) was simulated by MATLAB/Simulink software. The proposed back-to-back converter was used at the primary side of the distribution transformer to compensate for the voltage sag and swell issues. The simulation results were obtained under different conditions such as various supply voltages and various loads. Hence, the proposed system has the ability to regulate the output voltage under various conditions with ±10%.
21
Anantwar, Harsha, Shanmukha Sundar i B. R. Laksmikantha. "Optimal controllers design for voltage control in Off-grid hybrid power system". International Journal of Electrical and Computer Engineering (IJECE) 9, nr 6 (1.12.2019): 4586. http://dx.doi.org/10.11591/ijece.v9i6.pp4586-4597.
Pełny tekst źródłaStreszczenie:
<p>Generally, for remote places extension of grid is uneconomical and difficult. Off-grid hybrid power systems (OGHPS) has renewable energy sources integrated with conventional sources. OGHPS is very significant as it is the only source of electric supply for remote areas. OGHPS under study has Induction generator (IG) for wind power generation, Photo-Voltaic source with inverter, Synchronous generator (SG) for Diesel Engine (DE) and load. Over-rated PV-inverter has capacity to supply reactive power. SG of DE has Automatic voltage regulator for excitation control to regulate terminal voltage. Load and IG demands reactive power, causes reactive power imbalance hence voltage fluctuations in OGHPS. To manage reactive power for voltage control, two control structures with Proportional–Integral controller(PI), to control inverter reactive power and SG excitation by automatic voltage regulator are incorporated. Improper tuning of controllers lead to oscillatory and sluggish response. Hence in this test system both controllers need to be tune optimally. This paper proposes novel intelligent computing algorithm , Enhanced Bacterial forging algorithm (EBFA) for optimal reactive power controller for voltage control in OGHPS. Small signal model of OGHPS with proposed controller is tested for different disturbances. simulation results are compared with conventional method , proved the effectiveness of EBFA.</p>
22
Mrazova, Katerina, Jaromir Bacovsky, Zuzana Sedrlova, Eva Slaninova, Stanislav Obruca, Ines Fritz i Vladislav Krzyzanek. "UranyLess Low Voltage Transmission Electron Microscopy: A Powerful Tool for Ultrastructural Studying of Cyanobacterial Cells". Microorganisms 11, nr 4 (29.03.2023): 888. http://dx.doi.org/10.3390/microorganisms11040888.
Pełny tekst źródłaStreszczenie:
Sample preparation protocols for conventional high voltage transmission electron microscopy (TEM) heavily rely on the usage of staining agents containing various heavy metals, most commonly uranyl acetate and lead citrate. However high toxicity, rising legal regulations, and problematic waste disposal of uranyl acetate have increased calls for the reduction or even complete replacement of this staining agent. One of the strategies for uranyless imaging is the employment of low-voltage transmission electron microscopy. To investigate the influence of different imaging and staining strategies on the final image of cyanobacterial cells, samples stained by uranyl acetate with lead citrate, as well as unstained samples, were observed using TEM and accelerating voltages of 200 kV or 25 kV. Moreover, to examine the possibilities of reducing chromatic aberration, which often causes issues when imaging using electrons of lower energies, samples were also imaged using a scanning transmission electron microscopy at 15 kV accelerating voltages. The results of this study demonstrate that low-voltage electron microscopy offers great potential for uranyless electron microscopy.
23
Ohanu, Chibuike Peter, Kenneth Chinonso Odo, Luke Uwakwe Omeje i Tole Sutikno. "Output performance evaluation of the automatic voltage regulator system on pre-filter control technique". International Journal of Power Electronics and Drive Systems (IJPEDS) 14, nr 2 (1.06.2023): 789. http://dx.doi.org/10.11591/ijpeds.v14.i2.pp789-798.
Pełny tekst źródłaStreszczenie:
<p>Automatic voltage regulator (AVR) is used at each generating station or synchronous generators to maintain voltage supply at steady state or at a constant value otherwise the performance of the generator will be affected. The combination of AVR system with controllers clears fluctuation due to variation in load, speed, temperature, and power factor. This causes deviation in generator’s voltage and damage to power equipment. This work presents performance enhancement of AVR system using Proportional Integral and Derivative (PID) with pre-filter control technique. The enhanced performance was achieved by designing a nonlinear model of a synchronous generator, a PID controller and a low pass filter or pre-filter using MATLAB/Simulink model. The introduction of the proposed PID controller with LPF at load variation of 20 seconds, reduces the rise time and the peak time to 5.2975 seconds and 12.31 seconds respectively. This increases the overshoot and the settling time to 4.28 seconds and 17.60 seconds. However, the developed scheme provides a stable time response performance for various desired generator voltages considered. The performance of the proposed scheme was compared with conventional PID controlled AVR system without LPF. The proposed scheme provides more stability as indicated by the percentage overshoot, which is 4.5788% (for PID) and 4.2765% (for PID with prefilter). This has contributed to knowledge an AVR control system with better performance in terms of rise time, peak time, overshoot and settling time for stabilized generator output voltage.</p>
24
Choe, Young-Joe, Hyohyun Nam i Jung-Dong Park. "A Low-Dropout Regulator with PSRR Enhancement through Feed-Forward Ripple Cancellation Technique in 65 nm CMOS Process". Electronics 9, nr 1 (12.01.2020): 146. http://dx.doi.org/10.3390/electronics9010146.
Pełny tekst źródłaStreszczenie:
In this paper, a low-dropout (LDO) regulator with an enhanced power supply rejection ratio (PSRR) is proposed with a feed-forward ripple cancellation technique (FFRC) in 65 nm CMOS technology. This technique significantly improves the PSRR over a wide range of frequencies, compared to a conventional LDO regulator. The LDO regulator provides 35–76.8 dB of PSRR in the range of 1 MHz–1 GHz, which shows up to 30 dB of PSRR improvement, compared with that of the conventional LDO regulator. The implemented LDO regulator has a dropout voltage of 0.22 V and a maximum load current of 20 mA. It can also provide an output voltage of 0.98 V at a range of 1–1.3 V of the input voltage. The load regulation is 2.3 mV/mA while the line regulation is 0.05 V/V. The circuit consumes 385 μA with an input voltage of 1.2 V. The total area without pads is 0.092 mm2.
25
Bo, Liang, Yu Ren Li, Lei Xu i Jiu Li Lu. "Research on Voltage Regulator System of Aircraft Power Generation System". Advanced Materials Research 588-589 (listopad 2012): 552–57. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.552.
Pełny tekst źródłaStreszczenie:
The paper analyzed the composition of the aircraft synchronous generator system. The simulation model of the three-stage synchronous generator is established in the environmental of MATALB according to the motion equation of generator and coordinate transformation. Proposed a control algorithm based on the Sliding-mode Variable Structure Control (SVSC) theory after analyzed the conventional control algorithm of voltage regulator. Particularized the realized method of the SVSC algorithm is proposed. Simulation of both control algorithms were conducted under MATLAB. Simulation results indicated the validity of the SVSC algorithm and advantages against conventional control algorithm.
26
Wang, Songlin, Shuang Feng, Hui Wang, Yu Yao, Jinhua Mao i Xinquan Lai. "A novel high accuracy bandgap reference voltage source". Circuit World 43, nr 4 (6.11.2017): 141–44. http://dx.doi.org/10.1108/cw-04-2017-0019.
Pełny tekst źródłaStreszczenie:
Purpose This paper aims to design a new bandgap reference circuit with complementary metal–oxide–semiconductor (CMOS) technology. Design/methodology/approach Different from the conventional bandgap reference circuit with operational amplifiers, this design directly connects the two bases of the transistors with both the ends of the resistor. The transistor acts as an amplifier to amplify the change of voltage, which is convenient for the feedback regulation of low dropout regulator (LDO) regulator circuit, at last to realize the temperature control. In addition, introducing the depletion-type metal–oxide–semiconductor transistor and the transistor operating in the saturation region through the connection of the novel circuit structure makes a further improvement on the performance of the whole circuit. Findings This design is base on the 0.18?m process of BCD, and the new bandgap reference circuit is verified. The results show that the circuit design not only is simple and novel but also can effectively improve the performance of the circuit. Bandgap voltage reference is an important module in integrated circuits and electronic systems. To improve the stability and performance of the whole circuit, simple structure of the bandgap reference voltage source is essential for a chip. Originality/value This paper adopts a new circuit structure, which directly connects the two base voltages of the transistors with the resistor. And the transistor acts as an amplifier to amplify the change of voltage, which is convenient for the feedback regulation of LDO regulator circuit, at last to realize the temperature control.
27
Kilani, Dima, Baker Mohammad i Mohammad Alhawari. "Switched Inductor DC–DC Boost Regulator Using Voltage-to-Time Controller for TEG Applications". Energies 15, nr 9 (3.05.2022): 3330. http://dx.doi.org/10.3390/en15093330.
Pełny tekst źródłaStreszczenie:
This paper presents a switched inductor (SI) DC–DC boost regulator designed for thermoelectric generator (TEG) applications. To boost and regulate the output voltage, two feedback loops are implemented which control the duty cycle of the SI clock. The first loop consists of a pulse skip modulation (PSM) controller that compares the load voltage and reference voltage. Based on the comparison output, the PSM will either pass or bypass the modulated pulse width signal generated from the second loop. The second loop replaces the conventional circuit design of the pulse width modulation (PWM) with a voltage-to-time converter (VTC). The VTC converts the difference between load and supply voltage to time delay resulting in a modulated pulse width. This work is the first to report on utilizing VTC circuit in the SI boost regulator. The proposed SI boost regulator is designed using 65 nm CMOS technology which converts the TEG voltage of 50 mV to support dynamic voltage scaling in the range of 0.6 V to 0.8 V. The PSM and PWM controller loops can tune the duty cycle of the clock in the range of 0 to 70%. It achieves a peak efficiency of 60.9% at 30 μW load power. Comparing the proposed single-stage SI boost regulator with the conventional two cascaded stages of switched-inductor boost converter followed by switched capacitor regulator, the area is reduced by 9.6× and power efficiency is increased by 1.35×.
28
Et. al., K. Muralidhar Goud,. "Stability analysis of Automatic Voltage Regulator using Fractional Order Controller". Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, nr 2 (10.04.2021): 780–87. http://dx.doi.org/10.17762/turcomat.v12i2.1084.
Pełny tekst źródłaStreszczenie:
We aim to design a fractional order robust control system. It is an advanced model of classic PID controller whose order will be non-integer.PID controller that we generally use has many advantages and disadvantages with respect to the disadvantages like, it doesn’t give accurate values of constants, exact values of the time domain parameters as well as frequency domain parameters of the control system and we have more robust problem. Wearable electronic based an automatic voltage regulator can automatically preservesthe terminal voltage of generator at a fixed value under varyingly load and operating temperature. AVR controls output by sensing the output voltage at a power-generating coil and compares it to a stable reference. The combination of fractional order controller with an automatic voltage regulator is proved to be better than conventional controllers.
29
Yang, Ying, Jing Yuan i Hu Zhang. "Regulator Design of Vector Control System". Advanced Materials Research 383-390 (listopad 2011): 7082–89. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.7082.
Pełny tekst źródłaStreszczenie:
A Decoupling method based on feedforward voltage compensation is adopted to eliminate completely the coupling between exciting current and torque current. Based on conventional design methods of single-variable linear system , the paper analyses and designs detailedly the flux loop, speed loop and current loop. A design method based on double closed-loop PI regulator for speed sensorless vector control system is proposed. Through experimental results, we demonstrate its good performance.
30
Garfi, Oumaima, Helmi Aloui i Nadia Chaker. "Impacts of photovoltaic power source intermittence on a distribution network". International Journal of Electrical and Computer Engineering (IJECE) 9, nr 6 (1.12.2019): 5134. http://dx.doi.org/10.11591/ijece.v9i6.pp5134-5142.
Pełny tekst źródłaStreszczenie:
<span lang="EN-US">The integration of the photovoltaic (PV) solar systems into distribution networks has brought new challenges to the network planners. One of the most interesting is to prevent the impacts of the PV intermittent character on the steady state system operation conditions. This work is aimed to investigate such effect on voltage performance, conventional generator daily behavior and automatic voltage regulator operation. Simulations were conducted on a 33-bus IEEE radial distribution power system. In order to provide a reliable study, a real PV power profile was considered. Obtained results over a period of 24 hours revealed that the PV integration contributes to an enhancement of the overall voltage profile, a considerable saving in the total amount of the produced active power and a reduction of power losses. However, the PV intermittent character causes significant transformation in buses voltages daily profiles as well as changes in production plan. To sum up, this paper reports the alterations, caused by the PV source intermittence, which must be taken into consideration by the distribution networks planners to maintain the overall network parameters within safe operating condition</span>
31
Ghayyoor, Muhammad, Mian Muhammad Amir Ayaz, Ajmal Farooq i M. Ali. "Design of an integrated SEPIC and Buck Converter for High Step-down Applications". International Journal of Advanced Natural Sciences and Engineering Researches 7, nr 6 (25.07.2023): 214–23. http://dx.doi.org/10.59287/ijanser.1156.
Pełny tekst źródłaStreszczenie:
To overcome the issues related to special power supply called voltage regulator module (VRM) used for microprocessors, a special DC-DC converter will be designed in this work in which single-ended primary inductor (SEPIC) converter and the inverted form of buck converter are combine. As per available literature the problems associated with conventional VRM’s are slow transient response and narrow duty cycle. Other issue related to the voltage regulator module is the high voltage stress that occurs on switches of VRM. The solution to these problems is presented in the form of a new proposed dc-dc converter topology in which the single ended primary inductor is combined with the inverted form of buck converter. The proposed topology has the advantages of reducing the transient time at moderate duty cycle because of the parallel combination of the inductor. Similarly, the parallel combination of capacitor will step down the voltage from 12v to the appropriate voltage level required for the microprocessor. The steady state operation and transient state operation of the proposed VRM is discussed in this thesis. Various operating states of proposed converter are discussed and related equations for voltage gain, voltage stress and transient response have been derived. Output waveforms are plotted, and mathematical modeling is carried out. Simulation results for proposed and conventional VRM are obtained and from comparison of results, it is clear that proposed VRM is good in performances compared to conventional VRM’s.
32
Ghayyoor, Muhammad, Mian Muhammad Amir Ayaz, Ajmal Farooq i M. Ali. "Design of an integrated SEPIC and Buck Converter for High Step-down Applications". International Conference on Applied Engineering and Natural Sciences 1, nr 1 (21.07.2023): 436–44. http://dx.doi.org/10.59287/icaens.1036.
Pełny tekst źródłaStreszczenie:
To overcome the issues related to special power supply called voltage regulator module (VRM) used for microprocessors, a special DC-DC converter will be designed in this work in which single-ended primary inductor (SEPIC) converter and the inverted form of buck converter are combine. As per available literature the problems associated with conventional VRM’s are slow transient response and narrow duty cycle. Other issue related to the voltage regulator module is the high voltage stress that occurs on switches of VRM. The solution to these problems is presented in the form of a new proposed dc-dc converter topology in which the single ended primary inductor is combined with the inverted form of buck converter. The proposed topology has the advantages of reducing the transient time at moderate duty cycle because of the parallel combination of the inductor. Similarly, the parallel combination of capacitor will step down the voltage from 12v to the appropriate voltage level required for the microprocessor. The steady state operation and transient state operation of the proposed VRM is discussed in this thesis. Various operating states of proposed converter are discussed and related equations for voltage gain, voltage stress and transient response have been derived. Output waveforms are plotted, and mathematical modeling is carried out. Simulation results for proposed and conventional VRM are obtained and from comparison of results, it is clear that proposed VRM is good in performances compared to conventional VRM’s.
33
Anwar, N., A. Hanif, M. U. Ali i A. Zafar. "Chaotic-based particle swarm optimization algorithm for optimal PID tuning in automatic voltage regulator systems". Electrical Engineering & Electromechanics, nr 1 (23.02.2021): 50–59. http://dx.doi.org/10.20998/2074-272x.2021.1.08.
Pełny tekst źródłaStreszczenie:
Introduction. In an electrical power system, the output of the synchronous generators varies due to disturbances or sudden load changes. These variations in output severely affect power system stability and power quality. The synchronous generator is equipped with an automatic voltage regulator to maintain its terminal voltage at rated voltage. Several control techniques utilized to improve the response of the automatic voltage regulator system, however, proportional integral derivative (PID) controller is the most frequently used controller but its parameters require optimization. Novelty. In this paper, the chaotic sequence based on the logistic map is hybridized with particle swarm optimization to find the optimal parameters of the PID for the automatic voltage regulator system. The logistic map chaotic sequence-based initialization and global best selection enable the algorithm to escape from local minima stagnation and improve its convergence rate resulting in best optimal parameters. Purpose. The main objective of the proposed approach is to improve the transient response of the automatic voltage regulator system by minimizing the maximum overshoot, settling time, rise time, and peak time values of the terminal voltage, and eliminating the steady-state error. Methods. In the process of parameter tuning, the Chaotic particle swarm optimization technique was run several times through the proposed hybrid objective function, which accommodates the advantages of the two most commonly used objective functions with a minimum number of iterations, and an optimal PID gain value was found. The proposed algorithm is compared with current metaheuristic algorithms including conventional particle swarm optimization, improved kidney algorithm, and others. Results. For performance evaluation, the characteristics of the integral of time multiplied squared error and Zwe-Lee Gaing objective functions are combined. Furthermore, the time-domain analysis, frequency-domain analysis, and robustness analysis are carried out to show the better performance of the proposed algorithm. The result shows that automatic voltage regulator tuned with the chaotic particle swarm optimization based PID yield improvement in overshoot, settling time, and function value of 14.41 %, 37.91 %, 1.73 % over recently proposed IKA, and 43.55 %, 44.5 %, 16.67 % over conventional particle swarm optimization algorithms. The improvement in transient response further improves the automatic voltage regulator system stability for electrical power systems.
34
Aribowo, Widi. "Focused Time Delay Neural Network For Tuning Automatic Voltage Regulator". EMITTER International Journal of Engineering Technology 7, nr 1 (15.06.2019): 34–43. http://dx.doi.org/10.24003/emitter.v7i1.315.
Pełny tekst źródłaStreszczenie:
This paper proposes a novel controller for automatic voltage regulator (AVR) system. The controller is used Focused Time Delay Neural Network (FTDNN). It does not require dynamic backpropagation to compute the network gradient. FTDNN AVR can train network faster than other dynamic networks. Simulation was performed to compare load angle (load angle) and Speed. The performance of the system with FTDNN-AVR has compared with a Conventional AVR (C-AVR) and RNN AVR. Simulations in Matlab/Simulink show the effectiveness of FTDNN-AVR design, and superior robust performance with different cases.
35
Chouaba, S. E., i A. Barakat. "Controlled Brushless De-Excitation Structure for Synchronous Generators". Engineering, Technology & Applied Science Research 9, nr 3 (8.06.2019): 4218–24. http://dx.doi.org/10.48084/etasr.2768.
Pełny tekst źródłaStreszczenie:
The main weakness of the brushless excitation system in a synchronous generator (SG) is the slow de-excitation response obtained during a load rejection. That is why voltage overshoots may be observed on the generator terminals. This behavior is mainly due to the exciter machine response time and the rotating diode bridge which is not able to quickly de-excite the generator by negative excitation voltages. This paper presents a new brushless de-excitation structure able to perform a quick de-excitation of the generator by providing controlled negative excitation voltage to the generator main field winding. The proposed structure is based on a new brushless de-excitation machine, called a control machine, and mounted on the same shaft of the generator and the brushless exciter. The brushless control machine is a low power one and used to transfer the orders from the voltage regulator to the discharge system located on the rotor side of the main generator. The dynamic performance of the proposed de-excitation system is evaluated in terms of system stability, voltage regulation response times and voltage overshoots during different load rejection tests. The proposed system is compared to the conventional brushless excitation system without the proposed de-excitation structure. In addition, a comparison is done with the static excitation system. The simulation tests are realized on an experimentally validated model of 11kVA synchronous generator developed in Matlab/Simulink.
36
Zhao, Shuangxing, Chenchang Zhan i Guigang Cai. "A 2 × VDD-Enabled Output-Capacitor-Free Low-Dropout Regulator with Fast Transient Response for Low-Cost System-on-Chip". Journal of Circuits, Systems and Computers 27, nr 09 (26.04.2018): 1850143. http://dx.doi.org/10.1142/s0218126618501438.
Pełny tekst źródłaStreszczenie:
This paper presents a [Formula: see text]-enabled output-capacitor-free CMOS low-dropout (LDO) regulator with fast transient response for cost-effective system-on-chip (SoC) power management applications with elevated-[Formula: see text] supply. All the MOS transistors used in the proposed LDO regulator are low voltage (LV) MOSFETs, hence saving the high voltage devices fabrication cost required in a conventional design. Two LV power transistors are cascaded in the power train. A mid-rail regulator is used to generate [Formula: see text] voltage for the power transistors as well as the main error amplifier to guarantee safe operation. The mid-rail regulator employs stacking transistors to handle the high supply voltage. Moreover, Miller compensation with adaptive biasing is used to achieve good stability and fast transient response. A proof-of-concept design is fabricated in a standard 0.18-[Formula: see text]m CMOS process which achieves 3.3–3.6[Formula: see text]V nominal input, 3.1[Formula: see text]V nominal output and 100[Formula: see text]mA loading capability with all the transistors being 1.8[Formula: see text]V MOSFETs.
37
Yang, Wei Bin, Shao Jyun Xie i Han Hsien Wang. "A Sub-1V 0.18um Output-Capacitor-Free Digitally Controlled LDO". Applied Mechanics and Materials 764-765 (maj 2015): 471–75. http://dx.doi.org/10.4028/www.scientific.net/amm.764-765.471.
Pełny tekst źródłaStreszczenie:
The new digital control loop of the low-dropout regulator (LDO) is presented. It is composed of coarse tracking circuit and fine tracking circuit, and no external output capacitor is required to stabilize the control loop. The proposed method makes the quiescent current lower than conventional analog LDOs. The operational amplifier of the conventional LDO fails to operate at 0.7V, and the developed digital LDO in 0.18um CMOS achieved the 0.7V input voltage and 0.5V output voltage with 99.99% current efficiency and 2.6-μA quiescent current at 20mA load current. Therefore, the proposed DLDO is suitable for low power applications.
38
Narasipuram, Rajanand Patnaik, i Subbarao Mopidevi. "A Novel Hybrid Control Strategy and Dynamic Performance Enhancement of a 3.3 kW GaN–HEMT-Based iL2C Resonant Full-Bridge DC–DC Power Converter Methodology for Electric Vehicle Charging Systems". Energies 16, nr 15 (4.08.2023): 5811. http://dx.doi.org/10.3390/en16155811.
Pełny tekst źródłaStreszczenie:
The conventional resonant inductor–inductor–capacitor (L2C) DC–DC converters have the major drawbacks of poor regulation, improper current sharing, load current ripples, conduction losses, and limiting the power levels to operate at higher loads for electric vehicle (EV) charging systems. To address the issues of the L2C converter, this paper proposes an interleaved inductor–inductor–capacitor (iL2C) full-bridge (FB) DC–DC converter as an EV charger with wide input voltage conditions. It comprises two L2C converters operating in parallel on the primary side with 8-GaN switches and maintains the single rectifier circuit on the secondary side as common. Further, it introduces the hybrid control strategy called variable frequency + phase shift modulation (VFPSM) technique for iL2C with a constant voltage charging mode operation. The design requirements, modeling, dynamic responses, and operation of an iL2C converter with a controller are discussed. The analysis of the proposed concept designed and simulated with an input voltage of 400 Vin at a load voltage of 48 V0 presented at different load conditions, i.e., full load (3.3 kW), half load (1.65 kW), and light load (330 W). The dynamic performances of the converter during line and load regulations are presented at assorted input voltages. In addition, to analyze the controller and converter performance, the concept was validated experimentally for wide input voltage applications of 300–500 Vin with a desired output of 48 V0 at full load condition, i.e., 3.3 kW and the practical efficiency of the iL2C converter was 98.2% at full load.
39
Martins Bezerra, Pedro André, Florian Krismer, Johann Walter Kolar, Riduan Khaddam-Aljameh, Stephan Paredes, Ralph Heller, Thomas Brunschwiler i in. "Experimental Efficiency Evaluation of Stacked Transistor Half-Bridge Topologies in 14 nm CMOS Technology". Electronics 10, nr 10 (12.05.2021): 1150. http://dx.doi.org/10.3390/electronics10101150.
Pełny tekst źródłaStreszczenie:
Different Half-Bridge (HB) converter topologies for an Integrated Voltage Regulator (IVR), which serves as a microprocessor application, were evaluated. The HB circuits were implemented with Stacked Transistors (HBSTs) in a cutting-edge 14 nm CMOS technology node in order to enable the integration on the microprocessor die. Compared to a conventional realization of the HBST, it was found that the Active Neutral-Point Clamped (ANPC) HBST topology with Independent Clamp Switches (ICSs) not only ensured balanced blocking voltages across the series-connected transistors, but also featured a more robust operation and achieved higher efficiencies at high output currents. The IVR achieved a maximum efficiency of 85.3% at an output current of 300 mA and a switching frequency of 50 MHz. At the maximum measured output current of 780 mA, the efficiency was 83.1%. The active part of the IVR (power switches, gate-drivers, and level shifters) realized a high maximum current density of 24.7 A/mm2.
40
Liang, Jiawei. "Overview of Voltage Regulator Modules in 48 V Bus-Based Data Center Power Systems". CPSS Transactions on Power Electronics and Applications 7, nr 3 (30.09.2022): 283–99. http://dx.doi.org/10.24295/cpsstpea.2022.00026.
Pełny tekst źródłaStreszczenie:
The intermediate dc bus voltage in modern data center backend power supply is evolving from conventional 12 V to 48 V. It still requires the voltage regulator modules (VRM) to feed the terminal loads such as memory and computing units operating with very high current (> 100 A/module) and very low logic voltage (0.8 V-1.8 V). This makes it challenging to optimize the design of load-side VRMs with quadrupled input voltage. This paper comprehensively reviews the state-of-the-art 48 V VRMs and categorizes them according to passive component utilization. The first category is inductive solution which is further divided into coupled-inductor-based converters and transformer-based converters. The second category named capacitive solution is further divided into resonant switched-capacitor-based converters (Resonant SCC) and hybrid switched-capacitor-based converters (Hybrid SCC). Typical topologies are discussed, analyzed and summarized to perform a comprehensive performance comparison, such that the characteristics of different VRMs can be manifested. Some design considerations are also given to facilitate the design of the practical prototypes. Moreover, opportunities and challenges in the future data center power system are presented to provide technical insights.
41
Li, Fanyang, i Hao Jiang. "A High-PSRR Low Dropout Regulator for LNB Using the First-Stage Reference-Included Coarse-Filtering Technique". Journal of Circuits, Systems and Computers 24, nr 02 (27.11.2014): 1550022. http://dx.doi.org/10.1142/s021812661550022x.
Pełny tekst źródłaStreszczenie:
A high-PSRR low dropout regulator using the first-stage reference-included coarse-filtering technique is presented, for the reduced output ripple of the low noise block (LNB) power supply in the satellite set-top box. Compared with the conventional system, the regulator with the technique is characterized by the two successive negative feedback loops, so as to alleviate the output ripple of the power supply caused by the preceding DC–DC converter's modulation signal. With the technique, the ripple near to the frequency of the LNB supply voltage tuning signal (22 kHz) can be significantly alleviated. To further enhance the PSRR performance without the reference-by-pass capacitor, the bipolar-loop buffer amplifier and the reference-included coarse-filtering regulator are proposed. The circuits are extracted from the LDO layout and simulated with a 0.35 μm BCD process in Cadence. With the typical 16.3 V input supply voltage and loading current 100 mA, the line regulation corresponding to the DC supply voltage is achieved at -72 dB; the PSRR performance of the supply voltage ripple up to the frequency (100 kHz) is better than -70 dB; Moreover, the quiescent current without the loading impedance is less than 153 μA.
42
Tozser, B., I. Taczi i A. Torok. "The use of innovative tools in the medium voltage grid development, a case study of series voltage regulator". Renewable Energy and Power Quality Journal 21, nr 1 (lipiec 2023): 594–99. http://dx.doi.org/10.24084/repqj21.409.
Pełny tekst źródłaStreszczenie:
The rapid technological improvements concerning the renewable energy sources and the energy policy of the European Union, and the National Energy Strategy are leading to a rapid increase in the number of intermittent renewable power plants. Thus, new challenges emerge in the operation of the distribution system. To operate the system efficiently, the use of innovative technologies must be considered, because conventional network development strategies cannot always provide an optimal solution for the problem. This paper analyses the effects of largescale wind power generation on a medium voltage system and a solution of the problems faced through a case study of a serial voltage regulator. The difference between the profiles of generation and loads causes the residential transformers at the end of the line to encounter large, more than 8% voltage fluctuation. To assess the site’s voltage profile, time series symmetrical load flow calculations were performed. After the thorough analysis of the circumstances a serial voltage regulator device was implemented at 3 different nodes of the system and a placement analysis was carried out with statistical tools. The results showed a 3% decrease in the voltage fluctuation at the end of the line even when the device was far from these nodes; and with an optimal placement, the device could halve the largest voltage fluctuation on the line.
43
Goff, Daniel T., Steve J. A. Majerus i Walter Merrill. "A 200 °C Quad-Output Buck Type Switched Mode Power Supply IC". Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2014, HITEC (1.01.2014): 000022–27. http://dx.doi.org/10.4071/hitec-ta16.
Pełny tekst źródłaStreszczenie:
A high temperature (>200 °C), quad-output, buck type switched-mode power supply (SMPS) IC capable of operating over a wide input supply range of 6 V to 15 V is described. The IC is a compact power supply solution for multi-voltage microprocessors, sensors, and actuators. The SMPS topology is a 112 kHz fixed-frequency, synchronous buck converter with slope compensation. A novel internal feedback design enables the output voltages to be pin-programmed to one of three common supply voltages—5 V, 3.3 V, or 1.8 V—while an external resistor divider can also be used for arbitrary voltage programming. Integrated power supply output MOSFET switches minimize the external part count and synchronous rectification reduces power dissipation and improves current capacity. The IC was fabricated in a conventional, low-cost, 0.5 μm bulk CMOS foundry process. Patented circuit design techniques allow the IC to operate in excess of 200 °C and circuit operation was demonstrated at ambient temperatures up to 225 °C. The foundry process is optimized for 5 V applications, however, the IC accepts input voltages up to 15 V and can produce outputs up to 10 V by utilizing extended drain single- and double-sided NMOS and PMOS transistors for the linear regulator pass transistor, error amplifier, and SMPS switches. The high-side FETs are controlled through capacitive coupled level shift circuits to ensure the gate-oxide voltage limits are not exceeded while still maintaining fast signal transitions. The IC also includes a tunable, 25 MHz monolithic oscillator that is programmable over a SPI serial interface. The oscillator bias current is comprised of a programmable constant-gm bias current and a programmable PTAT bias current. The programmability can be used to set the oscillation frequency, but can also be used together with a calibration curve on a microcontroller to achieve a more stable oscillation frequency over temperature. The output current of the quad SMPS was limited to 70 mA by a lower than expected saturation current of the extended-drain PMOS switch devices. The system showed good line regulation (<0.1%) and 50% load step response stability (+/− 100 mV) at a nominal output current of 50 mA when tested at 200 °C ambient.
44
Hong, Qian-Rong, Pak-Ian Chan, Wai-Kit Sou, Cheng Gong i Chi-Seng Lam. "Linear Quadratic Regulator Optimal Control with Integral Action (LQRIC) for LC-Coupling Hybrid Active Power Filter". Applied Sciences 12, nr 19 (28.09.2022): 9772. http://dx.doi.org/10.3390/app12199772.
Pełny tekst źródłaStreszczenie:
Renewable energy generation and nonlinear load devices will generate harmonics and reactive power to power grids, resulting in current distortion and low power factors. To solve the power quality problems, the LC-coupling hybrid active power filter (LC-HAPF) is proposed, with lower DC-link voltage and lower cost compared with conventional active power filters (APFs). The LC-HAPF requires a controller to operate, therefore, hysteresis current control (HCC) and proportional current control (PCC) were proposed. However, they both result in significant steady-state error. Hence, linear quadratic regulator control (LQRC) with integral action (LQRIC) is proposed for the LC-HAPF in this paper to mitigate the steady-state error. The d-q-0 coordinate state-space model of the LQRIC-controlled LC-HAPF is derived, and a detailed design guideline of the weighting matrices Q and R of LQRIC is given. By the state-space model and weighting matrices, the gain matrix K of LQRIC can be acquired by MATLAB, thus a good steady-state performance can be ensured. Finally, the simulation results of different controllers for the LC-HAPF under 40V and 50V DC-link voltages are given to verify the effectiveness of the proposed LQRIC. The experimental results of LQRIC-controlled LC-HAPF are also given to verify the feasibility of the proposed LQRIC.
45
Chub, Andrii, Oleksandr Husev i Dmitri Vinnikov. "Simulation Study of Nonlinear PI-Controller with Quasi-Z-Source Derived Push-Pull Converter". Electrical, Control and Communication Engineering 4, nr 1 (1.12.2013): 26–31. http://dx.doi.org/10.2478/ecce-2013-0018.
Pełny tekst źródłaStreszczenie:
Abstract This paper is focused on the control issues of the quasi-Z-source derived push-pull converter with integrated magnetic elements. The proposed converter is intended for applications that require a high gain of the input voltage and galvanic isolation, i.e. power conditioning systems for renewable energy sources, such as variable speed wind turbines with direct driven permanent magnet synchronous generators. Magnitude and frequency of the output voltage of such turbines are variable due to intermittent nature of the wind power. Despite number of advantages converter has complicated dynamic behavior. Simulations showed change of stability margin depending on current operation point of the wind turbine and output load. Closed loop control system should provide fast response and stable operation in the wide range of wind speeds. Simulations showed that the conventional PI-controller with saturation cannot satisfy those requirements. Nonlinear PI-controller was derived by adding adjustment block to the conventional PI-controller. Adjustment block is drastically changing proportional and integral gains of the controller according to sign of the output voltage error. Proposed controller is compared with conventional one by means of simulation in PSIM. Simulation results prove that proposed nonlinear control system has improved regulator performance.
46
Liu, Xiao Wei, Bing Jun Lv, Peng Fei Wang, Liang Yin i Na Xu. "A Curvature-Compensated, High Power Supply Rejection CMOS Bandgap Reference for MEMS Micro-Accelerometer". Key Engineering Materials 483 (czerwiec 2011): 481–86. http://dx.doi.org/10.4028/www.scientific.net/kem.483.481.
Pełny tekst źródłaStreszczenie:
The reference is an important part in the accelerometer system. With the development of science and technology, the request of the performance of accelerometers is increasingly higher and the precision of reference directly affects the performance of accelerometers. Therefore, a reference voltage applicable to accelerometers is presented based on the analysis of basic principles of conventional bandgap reference (BGR) in this paper. A high-order curvature compensation technique, which uses a temperature dependent resistor ratio generated by a high poly resistor and a nwell resistor, effectively serves to reduce temperature coefficient of proposed reference voltage circuit and to a large extent improve its performance. To achieve a high power supply rejection ratio (PSRR) over a broad frequency range, a pre-regulator is introduced to remain the supply voltage of the core circuit of BGR relatively independent of the global supply voltage. The proposed circuitry is designed in standard 2.0μm CMOS process. The simulated result shows that the average temperature coefficient is less than 2ppm/°C in the temperature range from -40 to 120°C. The improvement on temperature coefficient (TC) is about 10 times reduction compared to the conventional approach. And the PSR at DC frequency and 1kHz achieves -107 and -71dB respectively at 9.0V supply voltage.
47
Mohamed, Mohamed A. A., Seang Shen Yeoh, Jason Atkin, Ahmed M. Diab, Mohsen Khalaf i Serhiy Bozhko. "Enhanced Starting Control Scheme for PMM-Based Starter/Generator System for MEA". Aerospace 10, nr 2 (11.02.2023): 168. http://dx.doi.org/10.3390/aerospace10020168.
Pełny tekst źródłaStreszczenie:
A control approach for aircraft Starter/Generator (S/G) with Permanent Magnet Machine (PMM) operating in Flux Weakening (FW) mode is presented. The proposed strategy helps the previous approaches which are adopted for the Variable Voltage Bus (VVB) or Voltage Wild Bus (VWB) concept for an aircraft Electric Power System (EPS), to cover a wide speed range in motoring and generation modes. Compared to prior works, the proposed control approach adjusts the q-axis reference voltage with a single current regulator, and the maximum available voltage provided by the converter is used to evaluate the d-axis voltage. By adopting the proposed approach, the DC bus voltage can be fully utilized, increasing aircraft efficiency by allowing the S/G system to operate at a wide range of speeds. The results of the analytical design and the performance of the system were verified by time-domain simulations using MATLAB/Simulink and experiments and compared to the conventional method.
48
Kumar, Ch Santosh, i S. Tara Kalyani. "Power Quality Improvement using Solar Fed Multilevel Inverter Based STATCOM". International Journal of Electrical and Electronics Research 10, nr 4 (30.12.2022): 1159–65. http://dx.doi.org/10.37391/ijeer.100464.
Pełny tekst źródłaStreszczenie:
The major goal about suggested technique is to use a PSO-based proportional-integral (PI) controller towards enhance power quality performance about three-phase grid-connected inverter system. An approach like aforementioned tries to stabilize output current & voltage, lower harmonics, & lessen DC link input voltage fluctuation. Through reducing error about voltage regulator & current controller schemes in inverter system, particle swarm optimization (PSO) technique was used towards adjust PI controller settings. When compared to conventional approach, simulation results show certain optimal parameters PI controller created among PSO produces better performance index results. According towards various research, reactive power supply can only modestly reduce voltage sags while totally mitigating harmonics using specialized power devices. Effective & dependable use about PV solar farm inverters as STATCOMs is required towards guarantee certain generating units stay connected towards grid during voltage sags & towards enhance system performance during abnormal circumstances.
49
Samman, Faizal Arya, Dea Fatriziah Hamka, Made Dharma Budy Diatmika i Ida Rachmaniah Sahali. "Adaptive Interpolated PI Gain Scheduling for Voltage Regulator in Solar Charge Controller Applications". E3S Web of Conferences 72 (2018): 02001. http://dx.doi.org/10.1051/e3sconf/20187202001.
Pełny tekst źródłaStreszczenie:
Buck-boost converter is one of the dc-dc convert0.er that can both increase and decrease the value of output voltage. Due to its wide output range, this converter is very appropriate for using in solar-based electric generation systems. To control the stable expected output voltage, this converter is usually integrated with feedback control. One of the old and widely used control techniques is PID control. However, conventional PID controls still have deficiencies, because the parameters of PID parameters are static so that for wide ranges of input or load will provide different transient responses. This paper will present a new PI control with an adaptive interpolated PI gain scheduling technique. The proposed control algorithm has been embedded and implemented in real microcontroller hardware and its performance has been tested under load change conditions, and the input voltage changes within the range of 8-22 V. Testing results show that PI control with gain scheduling technique produces better transient response compared to the traditional fixed PI controller. The time domain transient response measurements, under load changes within the range of 20-1000 Ohm, present that the proposed control algorithm give settling time value below 1.0 second, rise-time below 0.436 second, maximum overshoot below 0.5%, and the steady-state error below 0.3 V.
50
Alapati, Suresh, Sreehari Rao Patri i K. S. R. Krishna Prasad. "An Adaptively Biased Capacitor-Less Low Dropout Regulator with Improved Transient Performance". Journal of Circuits, Systems and Computers 26, nr 10 (27.02.2017): 1750146. http://dx.doi.org/10.1142/s0218126617501468.
Pełny tekst źródłaStreszczenie:
A novel fully on-chip low dropout (LDO) linear regulator with a supply voltage of 1.6[Formula: see text]V, dropout voltage of 200[Formula: see text]mV and a quiescent current of 64.4[Formula: see text][Formula: see text]A is presented in this paper. The slew rate limitations of conventional low dropout regulator (LDR) employing folded cascode structure are overcome by fixed bias LDR (FB LDR) with the usage of recycled transistors of conventional LDR. The FB LDR with its limited input common mode range limits the transient response. The adaptive bias LDR (AB LDR) overcomes these limitations of FB LDR and further enhances the transient performance. However, fast rise and fall time demands of advanced digital technology demand the regulator to respond to corresponding fast load changes. These challenges are addressed by an additional fast reacting path. An undershoot of 89.95[Formula: see text]mV for a load current changes from 0[Formula: see text]mA to 100[Formula: see text]mA and an overshoot of 150.1[Formula: see text]mV for a current change of 100–0[Formula: see text]mA is observed for the adaptive bias transient enhanced LDR. The load regulation of 20.6[Formula: see text][Formula: see text]V/mA and power supply rejection (PSR) of [Formula: see text]47.8[Formula: see text]dB@ 10[Formula: see text]kHz is achieved due to the improved closed loop gain and bandwidth of LDR. The standard 180[Formula: see text]nm UMC CMOS process is employed.