Modified Algorithm for Controlling the Traction Electric Motor of a Electric Vehicle

This paper discusses a modified control algorithm for a permanent magnet traction electric motor in an electric vehicle. The vehicle's electric drive system is implemented based on the principle of field-oriented vector control with the realization of the maximum torque per ampere (MTPA) control strategy. The modification in control consists of calculating the current torque on the motor shaft based on the measured flux-producing and torque-producing currents, forming the ratio of the calculated current torque to the current phase current of the electric motor, and adjusting the electric motor current reference for the MPTA block. The proposed model of traction electric motor is suitable not only for electric vehicles but also for other high-performance electric drive systems. Furthermore, it can ease the setting of PI controller of the control drive system and increase the efficiency of the traction system by decreasing the iron losses of the dynamic operation of electric motor.