Design And Research On Powerwtrain Mounting System For A Hybrid Electricl Bus

The NVH performance of vehicles determine the intrinsic quality of the automobile,the quality of powertrain mounting system design has an important impact on the Automobile NVH performance.Select the support parameters of the suspension system properly and a reasonable design of the vehicle powertrain mounting system can significantly reduce the vibration of the vehicle powertrain and vehicle body.Not only can improve the NVH performance of the whole vehicle,but also can prolong the service life of engine and other components.This paper,by consulting relevant literatures,summarizes the general research and related design theory of domestic and foreign scholars on the research of the powertrain mounting system.Based on the NVH status of a Hybrid Electric bus,the rigid body dynamic model of the suspension system with 6-point support is established,the suspension system is tested and analyzed theoretically,the quality parameters of the powertrain and the elastic parameters of the rubber pad are obtained,the installation position and the installation angle of each suspension point are measured in the vehicle coordinate system.By using MATLAB software,the calculation program of the inherent characteristics of the powertrain mounting system is developed and based on the energy decoupling method,the coupling degree of the suspension system is analyzed.Based on the sensitivity analysis of the stiffness parameters of the bus powertrain mounting system,the factors which have great influence on the stiffness of the suspension system are found out.Multi-objective optimization of the powertrain mounting system is carried out by using the three-direction stiffness of suspension system as the objective function and the suspension component as the design variableThe performance of the powertrain mounting system is analyzed from the time domain and frequency domain by ADAMS simulation software before and after the optimization combined with the comparison of vehicle vibration test.The rationality and validity of the optimized design are verified and the vibration isolation performance of the bus powertrain mounting system is improved and the NVH performance is improved.The research method used in this paper has some guiding significance for the structural design of the powertrain multi-point suspension system.