Novel reduced-order small-signal model of three-phase PWM rectifiers and its application in control design and system analysis

A reduced-order small signal model of three-phase PWM rectifiers is proposed. By combining the PWM switch model and equivalent multi-module model techniques in DC-DC power converters, a three-phase rectifier can be modeled as a DC-DC power converter with equivalent power capability and small-signal characteristics. This model reduces the system order to two, and greatly simplifies the control design and system analysis of three-phase power converters. In this paper, the proposed model is also used for control design and for system interaction analysis on the three-phase interface of a boost rectifier. The reduced-order model is verified with the d-q model, switching-model simulation and experimental results.