Regenerative Braking Control of Induction Motor in Electric Vehicles for Optimal Energy Recovery

This paper discusses the regenerative braking control as applied to Electric Vehicle with two control techniques along with their performance comparison. Regeneration is realized through V/F, a scalar control method and Field Oriented Control (FOC), and a vector control method for an inverter fed Induction motor. A simple Look up Table approach is proposed for a real-time implementation of V/F control, while in FOC, a methodology is proposed to shift the operating point from braking to generation region for optimal energy recovery. A model representing the commercial electric vehicle GM EV1 is developed in the present study that emulates a typical Vehicle environment. The test conditions are mainly chosen to include all possible drive ranges like acceleration, cruising and deceleration to demonstrate start-up, motoring and regeneration control through both scalar and vector control methods. The theoretical relationship between the synchronous and the rotor speeds are presented to bring out the mode change from motoring to regeneration. Furthermore, the regeneration is ascertained with the current and power flow results.