Driving Torque Control of Dual-Motor Powertrain for Electric Vehicles

Abstract

This paper investigates the driving torque control method for the dual-motor powertrain in electric vehicles (EVs) to achieve the performance of accurate vehicle speed tracking, seamless driving mode shift, and high energy efficiency. The configuration of the dual-motor powertrain is based on the parallel axle transmission structure, which does not contain any clutch or synchronizer. The powertrain provides three driving modes that are two single-motor driving modes and one dual-motor combined driving mode. A detailed dynamic model of the dual-motor powertrain is built to simulate the dynamic response of an EV. An energy management strategy (EMS) is used to select the driving mode and determine the ideal driving torque of two motors. The dynamic control strategy tries to track the ideal vehicle speed when uncertain parameters existed and avoid power interruption or impact during the mode shift. Three dynamic control strategies are proposed, which are the backward dynamic control strategy (BDCS), combined forward and backward dynamic control strategy (CFBDCS), and nested forward and backward dynamic control strategy (NFBDCS). The simulation results demonstrate that the NFBDCS has the best comprehensive performance in vehicle speed tracking, seamless mode shift, and good system energy efficiency.