Stabilizing control strategy of complementary energy storage in renewable energy system

To eliminate the instabilities in renewable energy generations such as wind and PV systems, which are mainly caused by weather factors, this paper presents a concept of complementary battery-supercapacitor energy storage system. The power deviations between the output of renewable system and a given power generation plan can be smoothed by this complementary system. To coordinate the different storage types effectively, a control strategy is given based on floating average method. Further, modeling methodologies and numerical simulations are correspondingly conducted to verify the effectiveness of the control strategy. Results show that, compared with single battery energy storage system, the complementary storage system can give full play to the high-power advantage of supercapacitor and the energy availability of battery respectively. This concept and its modeling can be used to relieve operating pressure of the single battery storage system when high power fluctuations come cross.