Three-phase single-stage step-up/down current rectifiers with sliding mode PWM current controller and low sensitivity voltage regulator

This paper presents an active sliding mode PWM current controller for three-phase single-stage step-up/down current rectifiers operating in continuous current mode. This current controller imposes the input line currents to track the desired suitable sinusoidal signal in phase with the input source voltages, ensuring a near unity power factor operation of the rectifier. With this control strategy, the input currents are actively shaped, being possible to maintain a near sinusoidal current even with high ripple DC inductor current. A low sensitivity output voltage regulator modulating the sinusoidal reference amplitude of the current controller is also proposed. Experimental results are presented, and the performance compared with the behaviour of the conventional proportional integral output voltage control.