Supercapacitor hybrid energy storage system applied to photovoltaic power generation

Abstract

In order to solve the problem of power pulsation at the DC bus side caused by uneven illumination or load fluctuation, a hybrid energy storage system for supercapacitors is proposed. In the hybrid energy storage circuit, inductors are added to form a high-frequency filter with the supercapacitor, and the supercapacitor absorbs the high-frequency current component of the DC side. The traditional droop control strategy is adopted to effectively filter the high-frequency current component of the battery side, and the battery is responsible for processing the low-frequency current component. The simulation results show that the proposed hybrid energy storage system can reduce the voltage pulsation of the DC bus, and the response and recovery speed is faster, which can effectively suppress the power pulsation on the side of the photovoltaic DC bus.