PWM rectifier

About: PWM rectifier is a research topic. Over the lifetime, 2254 publications have been published within this topic receiving 25614 citations.

Study on the control strategy of three-level PWM rectifier based on SVPWM

Abstract: The three-level PWM rectifier topology has been studied in this paper, and the decoupled state-space equations in synchronous rotating reference frame (d-q frame) were derived. The hierarchical controller structure is adopted, namely, the inner current-loop is responsible for reference current tracking and the outer voltage-loop is responsible for load regulation. The design methodologies for proportional-integral (PI) controllers are presented, for the inner current-loop and outer voltage-loop, respectively. The proposed three-level PWM rectifier based on space vector pulse-width-modulation (SVPWM) strategy is simulated using MATLAB/SIMULINK. Simulation results demonstrate that the proposed three-level PWM rectifier provides excellent performance both in steady-state and dynamic load variations. Pure sinusoidal waveforms can be achieved in grid currents with a unity power factor. Besides, energy feedback is realized.

Model predication control method of three-phase PWM (pulse width modulation) rectifier under unbalanced voltage

Abstract: The invention discloses a model predication control method of a three-phase PWM (pulse width modulation) rectifier under unbalanced voltage. The technical scheme mainly includes that the model predication control method of three-phase PWM rectifier under unbalanced voltage includes: negating input active power and input reactive power which are obtained by computation, enabling negated values to pass through proportional resonant controllers, obtaining second harmonic compensation voltages under a two-phase rotating coordinate system by means of compensating voltage computation, then obtaining second harmonic compensation voltages under a two-phase static coordinate system by means of reverse Park transformation, compensating the second harmonic compensation voltages under the two-phase static coordinate system into output voltage subjected to traditional model predication control, enabling voltage vectors with the minimum absolute values, which are differences of current given values and current predication values, to serve as optimal voltage vectors by value function selection, and using the optimal voltage vectors as switching signals for controlling power devices. The model predication control method of the three-phase PWM rectifier under unbalanced voltage is capable of effectively inhibiting second harmonic fluctuation of input power of the rectifier under the condition of unbalanced power grid voltage, and is simple in control structure, short in system delay and capable of simultaneously eliminating secondary pulses of input active power and input reactive power of the system.

Three-phrase pulse-width modulation (PWM) rectifier fault diagnosis method based on wavelet packet analysis and support vector machine

Abstract: The invention discloses a three-phrase pulse-width modulation (PWM) rectifier fault diagnosis method based on wavelet packet analysis and a support vector machine. The three-phrase PWM rectifier fault diagnosis method based on wavelet packet analysis and the support vector machine includes the steps: first, building a three-phrase PWM rectifier, determining classification principles and utilizing a wavelet packet arithmetic to analyze a direct current side output voltage of the rectifier; then, conducting energy spectrum and power spectrum analysis on a rebuilt small signal, determining a fault characteristic vector and building a data sample; and finally, choosing a support vector machine kernel function and a parameter, and building a multiple-value classifier so as to achieve fault diagnosis of the three-phrase PWM rectifier. The three-phrase PWM motor-generator set fault diagnosis method based on wavelet packet analysis and the support vector machine can improve fault diagnosis rate of the three-phrase PWM motor-generator set, avoid the problems of the data process and optimization of the traditional test method and effectively improve safety of an electric and electronic rectifier device.

A Robust Control Strategy for Three Phase Voltage t Source PWM Rectifier Connected to a PMSG Wind Energy Conversion System

Abstract: Permanent Magnet Synchronous Generator (PMSG) has been widely used in variable-speed Wind Energy Conversion System (WECS). Fuzzy logic control (FLC) of the generator side converter (rectifier) has the ability to have a good regulation of the DC link voltage regardless of the disturbances caused by the characteristics of the drive train. The main focus of this paper is to present a model for a voltage source rectifier which is connected to a PMSG in a wind turbine system, where a FLC based on Voltage Oriented Control (VOC) strategy is used to control the mentioned rectifier. The simulation results, using Matlab/Simulink, are presented to show the validity of the proposed model for the PWM rectifier compared to those obtained from the PI controller, and to evaluate the performance of the control strategy.

A modify technique to actively damp oscillation in the input LC filter of Three-phase PWM rectifier

Abstract: This paper proposes a modify technique to actively damp oscillation in the input LC filter of a three-phase PWM rectifier. The oscillation in the LC input filter of a three-phase PWM rectifier is damped by controlling voltage across the filter inductor. The principle is based on controlling the switches such that the input current of the filter follows the reference sine wave which is in-phase with the voltage to improve the power factor. The simulation results show that the proposed method can reduce current and voltage harmonic distortion at the point of common coupling and improve the power factor.