High power Dual Motor Drive System used in Fuel Cell vehicles

With the increasing concern of gas emission, climate change and energy crises, electric vehicles (EV), especially fuel cell hybrid electric vehicles (FCHEV), develop rapidly in current days. Meanwhile, permanent magnet synchronous motor (PMSM) drive systems are widely used in EV because of their advantages in wide speed ranges, high efficiency and power density. However, limited by manufacture technology and temperature characteristics of magnet materials, the application of PMSMs is restrained, especially for those which need high power level, such as heavy vehicles. This paper presents a high power Dual Motor Drive System (DMDS), including a dual motor and an integrated controller, which is a high performance solution for the problem concerned. The DMDS composes torque with a combining gearbox and transfers it to the drive shaft by a flange. Special attentions are given to the progresses that had been achieved in the 120 kW PMSM, the structure and control strategy employed by DMDS, and the optimized design to support a 17 tons Fuel Cell heavy bus. Finally some conclusions are illustrated.