Optimization design and performance comparison of different powertrains of electric vehicles

In order to improve the economy of electric vehicles, three dual-motor coupling power trains are proposed: dual-motor multi-mode coupling powertrain (DMMCP), dual-motor torque coupling powertrain (DMTCP), dual-motor speed coupling powertrain (DMSCP). Among them, DMMCP has two coupling modes of speed and torque, DMTCP can only realize torque coupling, DMSCP can only realize speed coupling. In order to evaluate their performance, they are compared with the traditional single-motor one-speed transmission powertrain (SMOSP) and single-motor two-speed transmission powertrain (SMTSP). The performance of a powertrain is not only related to its topology, but also greatly influenced by the selection of structural parameters. So this paper proposes a method of parameter optimization and optimal performance evaluation, which can obtain the optimal structural parameters while evaluating the performance of a powertrain. The results show that the dual-motor coupling powertrains are better than the traditional single-motor powertrains in the economic performance, and have a broad application prospect. (C) 2020 Elsevier Ltd. All rights reserved.