Torsional vibration analysis and optimisation of a hybrid vehicle powertrain

Aiming at a dual-motor torque coupling hybrid vehicle, its powertrain model is established by using the lumped mass method, and an engine transient torque model based on cylinder pressure is established to analyse its natural characteristics and torsional vibration response under typical working modes. Then, the sensitivity analysis of the main parameters of the powertrain such as flywheel inertia is carried out. Based on the analysis results, the multi-objective genetic algorithm is used to optimise the parameters of the powertrain. The results show that the optimised parameters can reduce the peak second-order angular acceleration of the transmission input shaft by 25.93% and 8.06%, and reduce the peak second-order angular acceleration of the driving wheel by 32.72% and 35.14% in two working modes.