Equivalent Circuit Model of Lead-acid Battery in Energy Storage Power Station and Its State-of-Charge Estimation Based on Extended Kalman Filtering Method

摘要

Based on the performance testing experiments ofthe lead-acid battery in an energy storage power station, themathematical Thevenin battery model to simulate the dynamiccharacteristics is established. The constant current intermittentdischarge experiments are used for obtaining the initial modelparameters values. Then the function relationship is fittedbetween the various parameters and the remaining power SOC.Combining the electrical characteristic equations in the relatedmathematical model, the voltage response data are produced inthe simulation environment. The obtained data are comparedwith the actual experimental data of the voltage to get thedifference, which is used to obtain the optimum modelparameters estimation online based on the unconstrainednonlinear optimization method. Finally, on the basis of theparameter identification results on the mathematical model, thestate space equations are established and the extended Kalmanfiltering method is used for SOC estimation. In the modelvalidation and algorithm simulation implementation, it can beseen form the simulation results that these models andestimation algorithm have high prediction precision and cansimulate the real-time dynamic battery, achieve the rapidconvergence, and satisfy the need of actual simulation andengineering application.