Optimal Charging Strategy for Electric Vehicle Battery

The increase in the emission rate of green-house gases mainly caused by the transport sector has led to growing concerns of global warming. Also, the prices of diesel of the diesel and petrol based fuels are getting higher day-by-day. This demands the inclusion of hybrid and plug-in hybrid vehicles in the transport sector. The major challenges that come in the way for increasing electric vehicle penetration are the charging strategy. The constant current-constant voltage strategy is a conventional method used for charging the batteries. The developed charging strategy in this thesis work is a constant temperature-constant voltage charging strategy. The strategy continuously monitors the charging temperature and with the help of a PID controller and a feed forward current term a charging current is generated. The objective is to develop time optimized charging strategy for electric vehicle batteries. The dynamic model of the charging strategy developed in MATLAB/Simulink software. The simulation studies have been carried out in different operating conditions like varying the charging state of charge of the battery i.e. at 0%, 20%, 50% and 80%. Simulation results show high current levels and faster charging and verify that the charging strategy is effective for real time operations.