SOC Estimation of LiFeO4 Battery Energy Storage System

Battery energy storage system as the voltage regulator device is widely used in distributed power generation system. LiFeO4 battery has broad application prospects in the energy storage system. Based on a large number of test data, the characteristic of LiFeO4 battery is analyzed systemically, and the battery equivalent circuit model is established. SOC estimation algorithm of LiFeO4 battery is got according to the extended Kalman filter (EKF) theory. In order to improve the estimation accuracy of SOC, the improvement of three aspects has been applied in the improved EKF method. The offline simulation results show that the improved EKF can improve the accuracy of SOC estimation effectively.