Multimode dual-motor electric vehicle system for eco and dynamic driving

Abstract

Electric vehicles (EVs) offer benefits in terms of reducing emissions and saving energy over other conventional vehicles. There have been various studies on EVs for energy efficiency and driving performance improvement. As an area of EV systems, dual-motor systems with planetary gear trains have been studied for fuel efficiency improvement, but they have limitations for torque vectoring and maximum torque compared to other typical systems. To overcome these limitations, a novel dual-motor EV system with a planetary gear train has been suggested for eco and dynamic driving modes. The system achieves variable motor operating points for energy efficiency improvement by using dual motors with a planetary gear train. Multiple driving modes are implemented by a synchronizer for torque vectoring and motor maximum torque driving. The suggested system was analyzed by comparison with a typical left-and-right-wheel independent drive dual-motor system with representative EPA test cycles. The novel dual-motor system shows not only the possibility of eco driving by improving fuel efficiency compared to typical dual-motor systems but also performance driving with torque vectoring functionality, which is not available for previous dual-motor systems with planetary gear trains.