Voltage Difference-Based Field-Weakening Control of Double-Rotor Hybrid Excitation Axial Flux Switching Permanent Magnet Motor

This paper investigates the operational performance of a novel Double-Rotor Hybrid Excitation Axial Flux Switching Permanent Magnet (DRHE-AFSPM) machine, combining the strengths of Flux-Switching Machines and Hybrid Excitation Synchronous Machines. The study analyzes the machine's structure and magnetic field adjustment principles, including inductance and flux linkage characteristics. A mathematical model is derived and a vector control-based drive system is established. The loading capacity of the DRHE-AFSPM motor is examined at low speeds using an id = 0 control approach based on a stage control strategy. For high-speed operation, a field-weakening control strategy is implemented, with the field-weakening moment determined based on the voltage difference. Simulations and experimental results demonstrate the DRHE-AFSPM motor's ability to fully utilize its torque with id = 0 control, highlighting its strong load capacity. Compared to speed-based field-weakening control strategies, the voltage difference-based approach offers improved inverter output voltage utilization and a broader speed regulation range. These findings suggest that the DRHE-AFSPM motor is a promising candidate for in-wheel motor applications in electric vehicles (EVs).