Study on current sensorless dynamic decoupling control of voltage source rectifier

Transitional current overshoot, DC offset and slow current response are the inherent drawbacks of conventional indirect or phase amplitude current control of three phase voltage source PWM rectifier. Analyses show that it is essentially a steady decoupling method, all the drawbacks are caused by current control based on steady state viewpoint. A new cascade dynamic decoupling compensator of boost PWM rectifier in the synchronous reference frame is firstly presented. The compensator not only decouples the crossing influence of d, q current in real time but also modifies the current nature response characteristic. The current response speed can be designed arbitrarily by assigning appropriate poles of the compensator. All above mentioned defects are eliminated after the compensator was employed. In addition, the proposed scheme doesn´t need current sensors at all. Simulation shows that it is a high performance and competitive control scheme.