Study of Deceleration Control using the Power Regenerative Brake to Improve the Ride Comfort in the Electric Vehicle

Ride comfort of regenerative brake in the electric vehicle is studied. Experiment device is consisted of the 3-phase synchronous motor, rotational load and the electrical double layer capacitor (EDLC) as the energy storage. The rotational load simulates the kinetic energy of the EV. The control method before improvement, large deceleration is generated when regenerative braking starts. It is caused by large current flowing into the circuit. As a result, regenerative energy is large. Thus, target value of deceleration is set. And deceleration control is studied by limitation of the current value by duty ratio control of the switching device in the circuit. And then it is a problem to be generated a large jerk when braking starts. To improve this problem, the drive motor is controlled by the speed command value given from the PC. As a result, current is suppressed and it is possible to be deceleration control on the target value.