A new controller structure for current source rectifiers

High power three-phase current type pulse width modulation (PWM) rectifiers are becoming increasingly popular as the front-end converter in power electronic systems due to unity displacement power factor control, reduced line current harmonics and tighter electromagnetic compatibility (EMC) regulation. A new control structure utilizing the concept of input-output linearization technique, pole and zero placements using the Butterworth polynomial is designed for current source rectifiers for unity power factor operation and dc voltage regulation. Utilization of the complex-variable form model voltage equations expressed in the synchronous reference frame simplifies the presentation and design of the controllers. Experimental and computer simulation results of a controlled rectifier confirm the validity of the proposed control technique.