A power battery charge estimation method

The present invention is a method of estimating the amount of battery charge, as follows: Ⅰ, get open circuit voltage as a function of SOC and the open circuit voltage; Ⅱ, measured SOC initial value; Ⅲ, sampling and get unscented Kalman filter SOC Initial estimates; ⅳ, according to the battery state equation and observation equation performed Sigma-point sampling unscented Kalman filter UT transform to obtain estimates for the measurements to estimate the battery SOC next time estimates and covariance. The present invention uses open circuit voltage and unscented Kalman filter with each other in SOC estimate, high estimate accuracy, the initial value of the SOC obtained by open circuit voltage, and SOC estimate revised up its estimation accuracy, unscented Kalman filter of wireless approximation process, reducing errors, calculation speed and improve the efficiency of the SOC estimation.