Phasor-Based Instantaneous Current Control of Single-Phase PWM AC/DC Converter.

Abstract

This paper presents a current control strategy for a single-phase PWM AC/DC converter. The input current is sinusoidal and an effective power factor is unity. Since the control variables of the single phase converter are sinusoidal, the conventional control strategy requires high control gains to achieve zero steady state error. However, the gains are limited because of sampling delay.To solve the problem, the authors propose a new current control scheme of a single-phase PWM converter which has two special features: One is that a fast response of current is achieved by introducing a converter model in the controller. Another one is that the steady-state AC current control error is canceled even if the parameter differences between the converter model and the actual converter exist. Moreover, the steady-state current error can be eliminated under low gains by a feedback loop of the fundamental component of current error.The experimental data show the proposed control to be effective.