An Adaptive Control Strategy for Minimizing Losses in EV Traction Systems Under Variable Speed Demands

With growing global concerns about energy issues and the increasing demand for Electric Vehicles (EVs), improving the system-level efficiency of EV traction systems has become more critical. This paper analyzes the overall losses and efficiency of an Electric Vehicle (EV) traction system within the rated speed range across different switching frequencies and explores how switching frequency and current quality affect the losses in the Interior Permanent Magnet Synchronous Motor (IPMSM) and the inverter. To minimize system losses, an adaptive switching frequency control strategy is proposed based on the conventional speed-current dual PI controller. This approach dynamically adjusts the controller parameter, i.e. the switching frequency, in real-time according to varying speed demands, while also limiting torque ripple. Simulation results confirm the effectiveness of the proposed control method.