Optimal Design of Electric Vehicle Power System with the Principle of Minimum Curb Mass

With the lightweight idea, an optimal design is developed for the powertrain of electric vehicles (EVs) to reduce the power consumption while maintaining excellent performance. Based on a prototype EV, the paper takes minimum curb mass as design principle, a single charge trip range mileage and whole life cycle of battery as constraints. The uniqueness of the design is the consideration in the selection of base speed and the associated change of motor and battery mass. The design is developed in two stages. With power and torque demand ensured, the first carries on the calculation and configuration of dynamic parameters to minimize curb mass for energy saving. The second stage verified the depth of discharge to guarantee good durability. The superiority of the design is demonstrated by comparing optimization results with original values.