Electric vehicle grade lithium polymer battery model using PSCAD

This paper presents the circuit model of a lithium polymer battery designed using Power Systems Computer Aided Design (PSCAD). The developed model takes into account the effect of temperature and discharge rate. The designed circuit is based on runtime model. Model takes into account a varying State of Charge (SOC). Model uses the SOC dependent parameters obtained from the curve fitting toolbox of the MATLAB. Using a runtime model this model is able to produce the accurate results in terms of DC response and overall battery runtime. The battery model developed is based on standalone application such as electric vehicle is discharging to grid through inverter with constant current profile. As a result the model is developed on discharge characteristic of the battery. This model is modular so it can be expanded to get the full battery bank voltage. PSCAD employs 3-D table for different parameters of the battery. Two axes are temperature and discharge rates. The third axis is for the parameters of the battery model. The simulation results differed from test results by maximum of 2.8%.