Shepherd Battery Model Parametrization for Battery Emulation in EV Charging Application

This paper deals with battery model parametrization in view of battery emulation applied to onboard electric vehicle (EV) chargers featuring efficient energy management system. For this purpose, accurate battery modeling and a good state of charge (SOC) estimation, are key issues. Hence Shepherd model is adopted as it corresponds to the one used by the target emulator and simulation environment PSIM. While the target emulator uses the original Shepherd model, the simulation environment uses the ameliorated model to enhance dynamics during battery current variation. A method to easily identify both models’ parameters is described. Simulation results comparing the datasheet typical characteristic curve to the simulated curves from the adopted model show the compatibility of the model to the real battery cells’ performance. Battery pack emulation presents good results while considering a Li-ion battery cell and as well as a battery pack for SOC higher than 20%.