The Study On The New Compensation Strategy Of The Dynamic Voltage Restorer

The impact of the voltage sag could be inhibited effectively by dynamic voltage restorer (DVR).The traditional analysis method of the compensation strategy has some shortcomings. The paper proposes a new analysis method which based on the load voltage, the new method not only has clear physical concept but also could determine the compensation scope easily. More importantly, it could be applied to the unbalanced load. Using the new analysis method, the paper analyzes the compensation strategy of the three single phase H-bridge DVR and proposes a improved minimum energy compensation strategy which could prolong the compensation time as long as possible.The paper also analyze the compensation strategy of the DVR that share the DC link adopting the new method, the zero active power compensation strategy is realized. The simulation result proves the correctness of the theory.