A Dynamic Reactive Power Control Strategy of LC-Type Energy Storage Converter for Achieving Zero Reactive Power and Improving Power Quality

Due to the reactive power caused by the LC filter, the output reactive power of energy storage converters can be hardly controlled at zero, which will reduce the efficiency of converters. Firstly, the mechanism and characteristics of the output reactive power error of the LC-type energy storage converter are analyzed theoretically. As the sampling current of the energy storage converter is the current of the filter inductance, the output reactive power of the energy storage converter is not zero. The reactive power error increases with the increase of the capacity of the filter capacitance. To address this issue, a dynamic reactive power control strategy of LC-type energy storage converters is proposed. By dynamically adjusting the reactive power command, the output reactive power of the LC-type energy storage converter can be stably controlled at zero under grid disturbance. Meanwhile, the design rules of the LC filter no longer need to consider the reactive power error caused by the capacitance, the LC filter can be further optimized, which can improve power quality. Finally, the experimental results verify the effectiveness of the proposed control strategy.