The Single-phase AC Regulator on Base of Bidirectional IGBT Switches

The Single-phase AC Regulator on Base of Bidirectional IGBT SwitchesIn the work one of the methods for regulation of sinus shape AC voltage for middle-power loads with activeinductive character is observed. Such a regulator keeping output voltage of sinus shape must be fast-reacting and work in closed-loop system. It's shown, that for providing such features Buck and Boost pulse regulators can be applied. The only difference from DC pulse converters is that electronic switches in the system must be with bidirectional conductivity. For this reason an IGBT transistors can be applied with implemented in structure reverse diodes and if such two transistors are connected in series and with contrary conductivity then at activating both one of them will be in on-state. Realization of AC regulators with such switches is described in the work. Results of computer modeling also are given. Output voltage ripples are investigated on subject of their range and efficiency of filtering equipment on LC base. Such regulators can be applied for instance in electrical transport self supply systems.

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Development of Robust Excitation Controller for Synchronous Generator

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.573.328 ◽

2014 ◽

Vol 573 ◽

pp. 328-333

Author(s):

R. Ramya ◽

K. Selvi ◽

M. Tamilvanan

Keyword(s):

Output Voltage ◽

Closed Loop ◽

Synchronous Generator ◽

Local Mode ◽

Small Signal ◽

Closed Loop System ◽

Robust Controller ◽

Sensitivity Approach ◽

Single Machine Infinite Bus ◽

The Stability

This paper deals with the design and evaluation of robust excitation controller for a single-machine infinite-bus power system. The design of the regulator guarantees the stability of the closed loop system and ensures the output voltage is maintained within an acceptable threshold. In addition, it damps out local mode oscillations for small signal disturbances. The designed robust controller is also analyzed under change in step input and disturbance, which limits the heavy oscillations on the speed ω and voltage. Glover-McFarlane loop shaping algorithm is applied in designing the robust excitation controller. Two different techniques such as Optimal control and mixed sensitivity approach is used in this paper. The performance of the AVR was analyzed and compared with IEEE type2 Exciter.

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A Single-Phase Nine-Level Boost Inverter

Energies ◽

10.3390/en12030394 ◽

2019 ◽

Vol 12 (3) ◽

pp. 394 ◽

Cited By ~ 1

Author(s):

Dai-Van Vo ◽

Minh-Khai Nguyen ◽

Duc-Tri Do ◽

Youn-Ok Choi

Keyword(s):

Output Voltage ◽

Single Phase ◽

Simple Structure ◽

Input Voltage ◽

Maximum Output ◽

Power Switches ◽

In Series ◽

Simulation And Experiment ◽

Laboratory Prototype ◽

Circuit Configuration

A novel single-phase nine-level boost inverter is proposed in this paper. The proposed inverter has an output voltage which is higher than the input voltage by switching capacitors in series and in parallel. The maximum output voltage of the proposed inverter is determined by using the boost converter circuit, which has been integrated into the circuit. The proposed topology is able to invert the multilevel voltage with the high step-up output voltage, simple structure and fewer power switches. In this paper, the circuit configuration, the operating principle, and the output voltage expression have been derived. The proposed converter has been verified by simulation and experiment with the help of PSIM software and a laboratory prototype. The experimental results match the theoretical calculation and the simulation results.

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Modeling and reliability analysis of three phase z-source AC-AC converter

Archives of Electrical Engineering ◽

10.1515/aee-2017-0055 ◽

2017 ◽

Vol 66 (4) ◽

pp. 731-743

Author(s):

Hanuman Prasad ◽

Tanmoy Maity

Keyword(s):

Reliability Analysis ◽

Output Voltage ◽

Closed Loop ◽

Supply Voltage ◽

Loop System ◽

Small Signal ◽

Closed Loop System ◽

Voltage Variation ◽

Three Phase ◽

Simulation Results

Abstract This paper presents the small signal modeling using the state space averaging technique and reliability analysis of a three-phase z-source ac-ac converter. By controlling the shoot-through duty ratio, it can operate in buck-boost mode and maintain desired output voltage during voltage sag and surge condition. It has faster dynamic response and higher efficiency as compared to the traditional voltage regulator. Small signal analysis derives different control transfer functions and this leads to design a suitable controller for a closed loop system during supply voltage variation. The closed loop system of the converter with a PID controller eliminates the transients in output voltage and provides steady state regulated output. The proposed model designed in the RT-LAB and executed in a field programming gate array (FPGA)-based real-time digital simulator at a fixedtime step of 10 μs and a constant switching frequency of 10 kHz. The simulator was developed using very high speed integrated circuit hardware description language (VHDL), making it versatile and moveable. Hardware-in-the-loop (HIL) simulation results are presented to justify the MATLAB simulation results during supply voltage variation of the three phase z-source ac-ac converter. The reliability analysis has been applied to the converter to find out the failure rate of its different components.

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