Analysis of the effects of gear trasmission structure on the electric vehicle performaces

In the present paper a comparative analysis of the performances of a battery electric vehicle (BEV) characterized by the use of different transmission systems are developed. With this aim a general model of a BEV has been implemented in Matlab environment. In order to coherently compare the energy performance when different configuration of BEV occurs, the New European Driving Cycle has been used. Moreover, a detailed model of the battery pack has been introduced in order to carefully estimate the combined effects of the design choices related both to the vehicle gears and to the regenerative braking. At this aim, a double gear transmission system for a BEV has been designed and the comparison with a one gear vehicle has been presented. The simulation results point out a grade climbing and top speed improvement in the double gear transmission BEV. In particular, by considering a suitable shifting gear strategy, a reduction of the energy provided by the battery and, consequently, an improved travel range have been obtained.