One Cost-effective Feedback Control Scheme for PWM Inverters Based on Repetitive Control

One digital control scheme, which is based on voltage differential feedback control and repetitive control, is proposed in this paper. For the first form, arbitrary pole placement can\´t be achieved, but the pole scope in the digital field that covers almost the applicable field, and higher accuracy in steady state is attained. For the latter form, arbitrary pole assignment can be achieved with the voltage differential feedback compensator inner loop, which can improve the dynamic characteristic of inverter; the repetitive control outer loop improves the steady state performance of inverter. The scheme, which can achieve the same control effectiveness as "state feedback pole assignment plus repetitive control" without current sensor, is proved on a PWM inverter whose control system is based on DSP TMS320F240