Dynamic Voltage Restorer with Compound Compensation Method

To realize the quick compensation of the sag voltage by the dynamic voltage restorer (DVR), reduce the influence on the sensitive load. This paper proposes a compound compensation based on pre-sag compensation and minimum energy compensation. Firstly, the compensation phasor diagrams of pre-sag compensation and minimum energy compensation are analyzed, and the respective output voltage and active power are obtained. Secondly, the working process of the compound compensation is explained, and the compensation phasor diagram and analytical formula are obtained. Finally, simulation and analysis results verify the effectiveness of the compensation strategy, which compensates voltage amplitude and phase, reduces energy loss, and improves voltage compensation time.