Unified robust zero-error tracking control of CVCF PWM converters

This paper proposes a unified robust zero-error tracking control scheme for constant-voltage-constant-frequency (CVCF) PWM converters to eliminate the tracking error in the presence. Based on the internal model principle, the proposed control scheme plugs a reference signal generator into the stable conventional feedback closed-loop system to accomplish zero error tracking of the dc or ac reference input. The design of the unified zero error tracking controller is systematically developed and the stability analysis of overall control system is discussed. Three examples of the proposed controlled CVCF converters, such as CVCF PWM inverter, boost-type PWM rectifier, and dc-dc PWM buck converter are studied to testify the validity of the proposed approach. Simulation and experimental results demonstrate satisfactory performance of the proposed unified robust zero error tracking controller even under parameter uncertainties and load disturbances.