Control and power quality improvement of three-phase PWM-Rectifier

Abstract

This thesis presents performance enhancement of PWM-rectifiers. Several control strategies have been proposed for the PWM-rectifier, such as voltage-oriented control (VOC), direct power control (DPC) and their combination: DPC with space vector modulation (DPC-SVM). Moreover, various virtual flux estimation techniques have been presented as a sensorless control algorithm in order to rise system reliability by decreasing the number of sensors and improving line-voltage estimation accuracy. Finally, a recent control strategy based on model predictive control has been introduced; this strategy reduces the complexity of the control circuit. All presented techniques have been investigated through simulation using MATLAB/Simulink software. The simulation results validate the presented control strategies. Sensorless predictive control features excellent PWM-rectifier performance as well as high robustness to network distortions.