NOVEL REDUCED-ORDER SMALL-SIGNAL MODEL OF A 3-PHASE PWM RECTIFIER ANDITS APPLICATION IN CONTROL DESIGN AND SYSTEM-ANALYSIS

A reduced-order (RO) small-signal model of three-phase pulse-width-mod ulation (PWM) rectifiers is proposed. By combining the PWM switch mode l and equivalent multimodule model techniques in dc-dc converters, a t hree-phase rectifier can be modeled as a dc-dc converter with equivale nt power capability and small-signal characteristics. This model reduc es the system order to two and greatly simplifies the control design a nd system analysis of three-phase converters. In this paper, the propo sed pc model is also used for control design and for system interactio n analysis on the three-phase interface of a boost rectifier. The RO m odel is verified with the d-q model, switching-model simulation, and e xperimental results.