Operating mode control research of mild hybrid electric vehicle

Based on the purpose of the practical engineering applications, the state transition between operating modes of HEV and the corresponding control strategy of the modes were analyzed. Through the opening variation of the accelerator pedal and the electronic throttle, the control strategy of HEV in driving mode was discussed in detail. The state logic model of the HEV’s operating modes was built in Matlab/Simulink environment. And the performances of the HEV were simulated in the ECE15+EUDC driving cycle operating mode. Finally the emission and fuel consumption contrast experiments between the traditional vehicle and HEV were carried out on the roll test station. The simulation and test results show that the output torque of the engine and ISG motor can meet with the driving cycle requirements. HC emission decreases by 73.3%, and CO emission decreases by 35% of HEV, compared to that of the traditional vehicle, and the total emissions are much less than Europe Ⅲ emission limits. At the same time, 100-kilometer fuel consumption approximately decreases by 15.1% and the fuel saving result is obvious.