Multi-Objective Optimization of Dual Motor Electric Powertrain Systems

Abstract:
Dual motor electric powertrains are gaining increasing interest in current research. The application of two electrical machines allows to optimally distribute the required wheel power to both machines and to realize powershift multi speed transmission without friction elements. However, the optimal design of dual motor powertrain is characterized by a huge design space. In this paper, a design approach is presented allowing to design and optimize dual motor electric powertrain systems holistically. Therefore, a graphical methodology is applied describing these powertrains from a functional perspective. Compared to existing component-based approaches, this methodology significantly reduces the number of design candidates, which must be investigated to cover the design space exhaustively. Additionally, an iterative dynamics simulation is proposed, which allows to investigate necessary mode transitions during full load acceleration. Consequently, the effects of mode transitions can be considered in the optimization process, ensuring that comfort demands are fulfilled. Within a case study, the design approach is applied to a relevant design problem.