Input Current Rate Limiter-Based Transient Oscillation Suppression of Input Filter Voltage and Current for Current-Source Three-Phase PWM AC/DC Converter

Abstract

PWM control is promising to achieve a unity power factor and to improve the input current distortion in a high performance current-source three-phase AC/DC converter system. In contrast to the voltage-source converter, the LC filter connected between the source and the converter may cause an LC resonance both in steady and transient states. Many reports have been published to improve the current distortion in steady state and to suppress the current oscillation in transient state of the current-source PWM converter by using the feedback control.This paper gives an analysis of the transient oscillation of the filter voltage and current, and proposes a simple open-loop suppression method by using the rate limiter of the input current reference. Furthermore, the design rule of the LC filter for the suppression control of the transient oscillation is described. The effectiveness of the proposed approach has been verified by experiments.