Research on active and reactive power coordinated control method of parallel compensator with energy storage

Abstract

Due to the high permeability of the distributed energy system under weak grid condition, the existence of line impedance reduces the voltage support capacity of the common coupling point, and the output intermittency of the energy system causes power imbalance during the system operation. To solve the problems mentioned above, this paper proposes a power coordinated control method based on energy-storage parallel compensator. Considering both the state of charge (SOC) of the energy-storage battery and the device capacity limitation, the parallel compensator under proposed control method performs real-time active and reactive power compensation to the grid, effectively solving the power fluctuation of the grid-connected system and ensuring the stability of the common coupling point voltage. The overall performance of the proposed control method is illustrated with the four-quadrant operation principle, the coordination control method mechanism, and the simulation-based performance. Finally, based on RT-BOX hardware-in-the-loop experimental platform, the experimental verification of different working conditions is carried out. The experimental results prove the effectiveness and accuracy of the proposed control method.