Structural topology and parameter optimization of torsional dampers used in parallel hybrid electric vehicles based on the working conditions

Hybrid electric vehicles (HEVs) are equipped with multiple power sources and involve complex mode-switching processes, which lead to intricate torsional vibration characteristics in their powertrains. This paper presents a novel clutch torsional damper with arc springs (CTD-AS) that combines the advantages of traditional clutch torsional dampers (CTDs) and dual-mass flywheels (DMFs). The structure and working principle of the CTD-AS are introduced in the paper, and a torsional damper parameter design method is discussed. During the study, a 13-degree-of-freedom concentrated mass model was established for an HEV powertrain, and optimization schemes based on multiple sets of operating conditions were obtained for a CTD, a DMF, and the CTD-AS. The optimized simulation results demonstrated that the average torsional vibration transmissibility value of the CTD-AS under the three working conditions was approximately 13.8% and 29.7% lower than that of the DMF and the CTD, respectively, and the overall performance is the best. The novel structural topology and parameter optimization method for the torsional damper of a parallel HEV proposed in this paper can effectively enhance driving smoothness under a variety of working conditions.