Real-time torque distribution strategy for an electric vehicle with multiple traction motors by particle swarm optimization

This paper introduces a torque distribution strategy for a pure electric vehicle with multiple traction motors in an electric propulsion system. This electric propulsion system consists of three motors - an indirectly - driven traction motor for front wheels and two in-wheel motors installed inside both rear wheels. A real-time torque distribution strategy is determined by particle swarm optimization theory to minimize energy consumption according to the torque-speed-efficiency maps of all the traction motors. Simulation results by hardware-in-the-loop show that the driving efficiency of the proposed real-time torque distribution strategy by particle swarm optimization is close to the results from the global optimization method by dynamic programming.