Traction Control Using a Disturbance Observer for Hybrid Electric Vehicles

This paper presents a practical approach designing a traction controller based on disturbance observer (DOB) in hybrid electric vehicles (HEVs). To conduct the traction control of HEVs, the proposed control scheme estimates disturbances in a specific frequency range caused by wheel-slips and reduces driving force in accordance with the estimated disturbance. A band pass filter is employed to the DOB to extract the disturbance in a specific frequency range causing wheel slip. In addition, a proportional-integral (PI) type regulator is applied to effectively reject the disturbances. To validate the proposed control algorithm, actual vehicle tests are performed using a C-segment HEV sport utility vehicle (SUV). The test results show that the proposed control algorithm achieved more enhanced energy efficiency as well as better ride comfort with maximizing traction force than the conventional control algorithm.