Modelling and Control of The Hybrid Storage System Providing Fast Frequency Support

With the rapid development of hybrid energy storage technology, the hybrid energy storage system composed of battery and supercapacitor has become an important means to provide fast frequency support to the power systems. In order to study the ability of hybrid energy storage system to provide fast frequency support to the power grid. This paper firstly describes the working mechanism of the hybrid energy storage system, and establishes a detailed model of the charging and discharging process of the hybrid energy storage system. Based on the detailed model, different droop control strategies of hybrid energy storage system are compared, and a simplified model is proposed. The accuracy of the simplified model is verified by comparing with the detailed model.