Modeling and active control of power-split hybrid electric vehicle launch vibration

One of the key challenges with the development of hybrid electric vehicles is the noise, vibration, and harsh behavior, specifically the uncomfortable ride experience during launch. This paper focuses on the driveline vibration caused by the quick response of the traction motor in the launch condition of hybrid electric vehicles. A torsional vibration differential equation for frequency analysis, including a Ravigneaux planetary gear set, a reducer, a differential, half shafts, and wheels, is thus built. Based on the equation, many components of the power-split system are simplified to make the controller design easy. Finally, wave superposition control strategy has been proposed to suppress the vibration, in which the concept is delaying part of the input to superimpose with the original input to eliminate the output wave. In order to optimize the control effect, parameters of the controller are chosen according to the system response. The simulation outcomes demonstrate that wave superposition control strategy is effective in attenuating the vibration generated by hybrid electric vehicles during launch conditions.