An analysis on the shifting schedule of a single-shaft parallel hybrid electric bus

Taking a single-shaft parallel hybrid electric bus as objective, a reverse test analytical method for shift schedule is proposed. First the test procedure is designed based on the shifting parameters assumed. Then a real vehicle test is conducted to analyze the effects of acceleration pedal position, vehicle speed, battery SOC, motor torque, engine torque and the combined torque of engine and motor on shifting schedule. As a result the acceleration pedal position and vehicle speed are found to be the shifting parameters of the vehicle. Finally through the shifting tests with different acceleration pedal positions, road conditions and driving styles, the shifting schedule of the vehicle is successfully worked out, validating the correctness of the analytical method proposed.