Research on Secondary Frequency Regulation Strategy for Hybrid Energy Storage Stations in Regional Power Grids

Aiming at frequency fluctuations caused by high-penetration renewable energy, a coordinated secondary frequency regulation strategy is proposed for hybrid energy storage stations in regional power grid. Hybrid energy storage stations contain electrochemical energy storage stations (EESSs) and compressed air energy storage stations (CAESSs). Complete mathematical models of concerned energy storage stations are constructed, and a multi-objective exponential distribution optimization (MOEDO) algorithm is proposed to optimize regulation cost, automatic generating control (AGC) command tracking and constrain the state of charge (SoC) of energy storage equipment. The proposed strategy rationally distributes secondary regulation instructions for hybrid energy storage stations and thermal power plants. In the end, simulation results on a two-area interconnected power grid are given to verify the effectiveness of proposed strategy. Results reveal that the presented method can effectively suppress frequency deviation and tie-line power oscillation and maintain SoC within a safe operating range.