A Virtual Admittance Control Strategy of Three-Phase Voltage Source PWM Rectifier Under Unbalanced Input Voltage Conditions

A virtual admittance control strategy is proposed for three-phase voltage source PWM rectifier by analysis on the time-domain relationship between three-phase AC current and three-phase AC voltage under unbalanced input voltage conditions. The strategy does not only simplify the control algorithm, but also realize wanted power factor by the Coordinate Transformation. With reduced computation and improved speediness, generalized integrator is also introduced to realize static error free tracking control of positive and negative sequence current on two-phase static frame. Extensive simulation and experimental results verify the correctness of the proposed control strategy.