Loss Minimization Based Energy Management for a Dual Motor Electric Vehicle

Abstract

The dual-motor electric vehicle has a simple structure, which enables the front and rear wheels to obtain adhesion at the same time. It can improve the acceleration characteristics of the vehicle and achieve high efficiency of the system. To optimize the propulsion efficiency, a power allocation method is designed to determine the torque ratio between the front and rear axle motors. This paper proposes an efficiency-based optimal energy management strategy for dual-motor driven electric vehicles. In this way, the remaining battery state of charge is improved by reducing vehicle power loss. The energy consumption of the vehicle is firstly determined by drive cycles. The optimal distribution factor is calculated to minimize the system loss at each time sample. This determines distributions of the traction, regeneration, and mechanical braking forces between two motors. Simulation analysis is conducted under drive cycles of NEDC and WLTC. Results show that the method can reduce the total energy consumption of the system. With the proposed method, the braking energy recovery rate is improved, which also enhances the economy of the whole vehicle under different driving conditions.