An Optimal Voltage Support Control Strategy Considering Active Power Balance Based on Cascaded Energy Storage System

This paper proposes a control strategy for voltage support and power balance between phases based on the cascaded system. The reference currents injected into the system are closely related to the grid-connected impedance and the grid voltage unbalance factor in the proposed strategy. Simultaneously, it focuses on the reasonable design of the negative-sequence current injection to achieve the proposed target for balancing active power among phases. In order to avoid excessive injection current, the maximum injected current is controlled within the safe and reliable operating range of the inverter. Finally, the proposed control strategy is simulated on Matlab/Simulink.