High dynamic response control of induction motor in high-speed region for electric vehicle drive system

Electric vehicle drive systems require fast torque response and high efficiency over a wide range of velocities. In this paper, a fast torque response control strategy suitable for the region above the base frequency is proposed based on an analysis of the impact of the efficiency optimization strategy on dynamic response. The operation characteristics of induction motors in typical drive cycles are analyzed at first, then an efficiency optimization strategy based on loss model and its corresponding fast torque response control strategy are proposed. The efficiency optimization strategy improves the motorpsilas efficiency in steady state, and the fast torque response control strategy distributes magnetizing current and torque current according to the voltage limit offset to achieve maximum torque output in the dynamic process. The strategy breaks through the limitation of traditional maximum torque control strategies based on the steady state analysis. The simulation and experimental results indicate that the proposed control strategy can provide fast torque responses above the base frequency in dynamic processes and reduce the impact on the electric vehiclepsilas dynamic response caused by the efficiency optimization strategy.