Active Control for the Through-the-road Parallel Hybrid Electric Vehicle Low Frequency Longitudinal Vibration

Through-the-road parallel (TTRP) hybrid electric vehicle (HEV) is composed of an internal combustion engine (ICE) and an electric motor mounted on the different axles. These two powertrains are coupling through the road-tire force. Because of the special architecture, the low frequency longitudinal vibration of this typology HEV has different vibration character at different power modes. Low frequency longitudinal vibration is one of the key factors of the vehicle drivability. Controlling the vehicle low frequency longitudinal vibration is one way to improve the vehicle drivability. The low frequency longitudinal vibration of TTRP HEV at different power modes is discussed and the simplified model is developed. Based on the simplified model of different power modes, a unified multiple-model predictive controller is designed. In order to evaluate the control effect, multiple power modes are simulated at special maneuver to compare the vehicle acceleration curve with and without controller. These maneuvers include Tip-in, Tip-out with different torque distribution. The results show that the suggested MMPC approach for TTRP HEV has good effect on the drivability improvement.