A Novel Three-Phase Three-Wire Dynamic Voltage Restorer

A novel optimal control method of three-phase three-wire Dynamic Voltage Restorer (DVR) and its simplified topological structure are proposed. Based on virtual-floating-ground analysis method, a time-domain mathematical model and the control equation of DVR's converter are established; the optimal feasible solution with minimum objective function value of the control equation is deduced. Compensation voltage detection is based on digital phase lock, and the switching time is calculated by line voltages, the control performance under the proposed control strategy is analyzed, which greatly improve the utilization rate of DC side voltage and the DVR's compensation capability. The simulation and experiment results of three-phase three-wire DVR under the proposed algorithm are given; the results show its validity and feasibility. (paper)