A Novel Driving and Regenerative Braking Regulation Design Based on Distributed Drive Electric Vehicles

Electric vehicles mainly work in urban conditions. Due to frequent acceleration and deceleration, the driving and braking torques vary in a large range as well as the motor efficiency. Distributed drive electric vehicles allow for an independent and accurate torque control of each wheel. Based on that, a novel driving and regenerative braking regulation (DRBR) with respect to energy-saving is developed. Firstly, economy-based objective function is established to optimize the vehicle efficiency under driving conditions. Its solutions, traction distribution coefficient, are derived under the constraints of desired driving torque, current RPM and motor property. Then according to the ideal braking force distribution curve and ECE regulations, the regenerative braking regulation is proposed combining friction brake and motor brake. Therefore it can guarantee both the braking stability and the energy recovery. Finally, the driving and braking regulation is verified with computer simulations based on the worldwide harmonized light vehicles test procedures. The simulation results indicate that the presented approach improves vehicle efficiency significantly.