Study on compound control technology of single-phase dynamic voltage restorer

In this paper, a novel composite control strategy is proposed, which contains the load current direct feedforward control strategy for the inner loop and the improved proportional resonant (PR) feedback control strategy for the outer loop. The fundamental voltage and current vectors are extracted by an improved adaptive algorithm. Then the reference values of the voltage loop and the current loop are got via vector calculation based on the reactive power compensation strategy. In this way, the suggested compound control technology can enhance the stability and fasten the responding speed at the same time for the dynamic voltage restorer (DVR) and make it suitable for compensating fundamental and harmonic frequency fluctuation and has the ability of power factor correction. The feasibility and effectiveness of the proposed algorithm are verified by the simulation and the experimental results. ©, 2015, The editorial office of Transaction of China Electrotechnical Society. All right reserved.