Driving-Mode Switching Regulation Comparison of Four-Wheel-Independent-Drive Electric Bus for Energy Conservation

Compared with the traditional electric vehicle whose drive axle is composed of one single electric motor and differential, four-wheel-drive electric vehicle with in-wheel motor has tremendous potential and freedom to design various chassis dynamic control system. In this paper, a driving-mode switching regulation applied to this kind of electric bus for energy conservation is presented, by using minimum- instantaneous-energy-consumption torque distribution method. According to the calculation result of instantaneous energy consumption at each moment, this method can minimize the driving energy consumption by adjusting the drive torque between two-wheels and four-wheels and raise driving efficiency by up-grading working load rate of the motor in driving or braking conditions. The simulation results show that minimum-instantaneous- energy-consumption torque distribution method will save 6.68% energy consumption compared with the full-time mean-distribution four-wheel driving-mode.