New Combined MTPA–VCLMT–CPR Control Strategy for IPMSM Drives in Vehicle Propulsion System

Abstract

The control of electric vehicles (EVs) is achieved through the management of their in-wheel motors, which are part of the electric traction system. This study has derived an algorithm strategy for the operation of interior permanent magnet synchronous motors (IPMSM) used in high-speed electric traction applications. The strategy combines the maximum torque per ampere control (MTPA) for low speeds and the control of the Voltage Current Limited Maximum Torque (VCLMT) and the Constant Power Region (CPR) for high speeds. By implementing this strategy, precise and independent control of the torque applied to each in-wheel motor is achieved, ensuring high torque at high speeds. This level of control is crucial for embedded systems. IPMSMs have been identified as a promising choice for electric vehicle applications due to their ability to generate reluctance torque, as well as their higher efficiencies, torque, and power densities. To ensure the smooth functioning of the IPMSM motor, a crucial component in electric vehicles, the proposed method incorporates a combination of three torque control strategies and divides the torque/speed characteristics into five distinct zones. The effectiveness of this strategy was confirmed through extensive simulation using MATLAB/Simulink. The numerical simulation results demonstrate exceptional traction system dynamics across a wide range of operating speeds.