The SOC estimation of battery based on the method of improved Ampere-hour and Kalman filter

In the independent photovoltaic systems, the accurate estimation of the remaining capacity of the battery will greatly extend the lifespan of the system and improve the reliability of the system. This paper based on the method of Ampere-hour, the initial state of charge (SOC) is estimated by the open-circuit voltage method, the initial SOC and the real time SOC is corrected by the Kalman filter algorithm, the initial SOC estimation error and the accumulated error of current is reduced to ensure the accuracy of the SOC estimation. Experiments were performed to test for 12V100AH lead-acid battery; the results show that the SOC is accurately estimated by the proposed algorithm.