Multiobjective Optimization of Powertrain Mode Switching With Hysteresis Control for Electric Heavy-Duty Vehicles

The powertrain of electric heavy-duty vehicles is typically composed of multiple motors and multi-speed transmissions, leading to a diverse range of operating modes. Due to the highly dynamic driving conditions and the necessity to optimize energy consumption, the powertrain undergoes frequent mode switching, which negatively impacts ride comfort. This paper proposes a multi-objective optimization method for mode switching with hysteresis control, where the hysteresis control effectively enhances driving comfort by setting appropriate hysteresis values. The optimal hysteresis value is determined by solving the Pareto front to balance energy consumption and ride comfort. The results demonstrated that the proposed method effectively balanced three cost functions, leading to significant reductions in gear shifting (e.g. 48.5% in C-WTVC) and motor switching (e.g. 51.0% in C-WTVC) with only a minimal increase in energy consumption (e.g. 1.1% in C-WTVC). The performance of the proposed method was validated through comparisons with the benchmark under six global standard driving cycles, confirming its effectiveness even without explicit cost function boundaries. This multi-objective optimization approach can be widely applied in the development of EMS that incorporate hysteresis control.