High-Performance Control of a Boost Type PWM Rectifier under Unbalanced Operating Conditions with Integral Variable Structure Control

This paper presents a simple and effective supply voltage unbalance correction approach for a PWM rectifier and a new current controller based on integral variable structure control (IVSC). The current commands in the proposed approach are generated by making the positive sequence current command in phase with the positive sequence voltage and the negative sequence current command 180 degree out of phase with the negative sequence voltage. By choosing current commands in this way, constant dc-link voltage together with sinusoidal input current at unity power factor can be achieved. Integral variable structure current controller in stationary frame is used to provide robustness and achieve high performance current tracking in the face of system uncertainties and disturbance. The existence and stability of sliding mode is ensured by using a proper reaching law approach. The effectiveness of the proposed supply voltage unbalance correction approach and integral variable structure based current controller are validated through experimental results