Synchronous control method for four in-wheel otors of electric vehicle (EV)

EV with 4 in-wheel motors has advantages of system´s light weight because it has respectively independent control system. But it is difficult that EV has to control four in-wheel motors at once. The speeds of four in-wheel motors are different each other, because the disturbance and over wheel of four in-wheel motors are not the same. EV is necessary to control synchronously. Velocity differences among in-wheel motors make vibrations to the electric vehicle and can cause rollover. However, when the EV direction needs to be changed, EV is not effective to control synchronously. So the rear wheel motors need synchronous control while the front wheel motors need individual velocity control for direction change. Therefore, this paper suggests the synchronous control and direction change method for four in-wheel motors of EV. The performance is verified with simulation using MATLAB SIMULINK.