Estimation of state of charge of battery based on Extended Kalman Filtering

Estimation of state of charge (SOC) is the key technique for electric vehicle power management system. A simple battery nonlinear equivalent model under AMESim is built. By using Extended Kalman Filter method, battery SOC is estimated on-line through optimal estimation in the sense of minimum-variance when battery current fluctuates wildly. Co-simulation result shows that Extended Kalman Filter method which can estimate SOC with error less than 1.8% has high accuracy.