Energy regeneration technique for electric vehicles driven by a brushless DC motor

The development of energy regeneration capability in electric vehicles can extend their driving range making them a competent alternative for conventional internal combustion engine vehicles. In this study, a novel energy regeneration technique, called a two-boost method, for electric vehicles driven by a brushless DC (BLDC) motor, a widely used motor in vehicular technology, is proposed. Based on this technique, the BLDC motor driver, which is selected to be a three-phase inverter, is converted into two simultaneous boost converters during energy regeneration periods in order to transfer energy from the BLDC motor into the battery and provide the braking force. Also, this method is compared with the single-boost method. The simulation and experimental results show that the amount of regenerated energy in this method is more than twice of that in the single-boost method. Moreover, it is observed that in the two-boost method, the motor speed changes linearly without any control of the electrical torque. In addition, since the amount of regenerated energy in this method as compared to the single-boost method is higher, the energy regeneration efficiency in this method is increased significantly.