Cascaded Fuzzy Controller for Electric Vehicle Traction System Battery Energy Management

This paper presents a battery energy management (BEM) technique for an indirect field oriented (IFO) induction motor driven electric vehicle (EV) traction system. The proposed technique is designed using two cascaded fuzzy logic controllers. The first fuzzy logic controller (FLC) generates the desired torque command current, Iq, to regulate the motor speed while the second fuzzy controller limits Iq based on the battery SOC. Computer simulations are developed for the entire EV traction system which is powered by a 450 V Li-ion battery bank. The simulation results even for a short period of 30 secs show that proposed BEM technique results in a reduction in the battery energy consumption and a lower degradation in the battery state-of-health (SOH) with little bit compromise on the motor acceleration.