Collaborative Control of Novel Uninterrupted Propulsion System for All-Climate Electric Vehicles

Over the past decade, the electric vehicle industry of China has developed rapidly, reaching one of the highest technological levels in the world. Nevertheless, most electric buses currently serve urban areas, being unsuitable for all-climate operations. In response to the objective of massively adopting electric vehicles for transportation during all the events of the 2022 Beijing Winter Olympics, a dual-motor coaxial propulsion system for all-climate electric vehicles is proposed. The system aims to meet operating requirements such as high speed and adaptability to mountainous roads under severely cold environments. The system provides three operating modes, whose characteristics are analyzed under different conditions. In addition, dual-motor collaborative control strategy with collaborative gearshift and collaborative power distribution is proposed to eliminate power interruption during gearshift process and achieve intelligent power distribution, thus improving the gearshift quality and reducing energy consumption. Finally, gear position calibration for all-climate operation and proper gearshift is introduced. Experimental results demonstrate the advantages of the proposed dual-motor coaxial propulsion system regarding gearshift compared with the conventional single-motor automatic transmission.