Algorithm for vehicle speed control when driving downhill for electrically powered vehicles

摘要

A control system is provided that prevents the speed of an electric vehicle from increasing on a downgrade by providing regenerative braking by a traction motor. The system includes an enabling circuit that provides an enabling signal when certain criteria are satisfied, such as a brake pedal and an accelerator pedal being inactive. The system further includes a controller that is enabled by the enable signal and receives a vehicle speed signal of the speed of the vehicle. The system also includes a switch that receives the enable signal and the vehicle speed signal. When the enable circuit provides the enable signal, the switch provides the controller with a speed setpoint for the last vehicle speed. When the vehicle speed signal exceeds the speed setpoint, the controller outputs a regenerative braking torque command to the traction motor to reduce the speed of the vehicle to the speed setpoint.