Simulation and Control of a Novel Two-Speed Uninterrupted Mechanical Transmission for Electric Vehicles

Development of electric vehicle (EV) technology leads to the growing performance requirements of driving motor. Introducing a two-speed transmission to EV offers the possibility of economic and dynamic performance improvement of the whole powertrain. This paper presents an innovative two-speed Uninterrupted Mechanical Transmission (UMT), allowing the seamless shifting between two gears. Considering the uncertain factors during gearshift, a robust controller is designed based on H∞ control method. An optimal controller based on linear quadratic regulator is adopted for comparison. The results indicate that the UMT adopting robust controller provides an improvement of dynamic performance and shifting comfort for EV.