NVH Performance Optimization Of Battery Electrical Vehicle

Under the call of the world,a new round of automobile revolution is about to come,Battery Electrical Vehicle are showing a blowout development,and major OEMs around the world have successively announced the time to stop the sale of internal combustion engine vehicles.The comfort of the whole vehicle needs to be paid attention to when the power part of the vehicle is changed,and people’s requirements for the quality and comfort of the vehicle are becoming more and more strict.Among them,quietness,as one of the signs of car comfort,is gradually sought after by people,and it has also become one of the factors that people consider when buying electric vehicles.Electric cars are quieter than conventional cars,but occupants often feel other noises prominent.Due to the lack of the concealment effect of the engine,the road noise and wind noise are particularly prominent when the vehicle is driving at high speed,and the noise generated when the air conditioner is running when the vehicle is idling is even more annoying.Therefore,the sound quality of electric vehicles has become one of the key elements of product competitiveness and user acceptance.This paper analyzes and optimizes the vibration and noise performance of Battery Electrical Vehicle from three aspects of road noise,wind noise and air conditioning system noise,so as to improve the NVH performance of the whole vehicle.In terms of road noise performance,the optimization analysis is carried out from the noise source and the noise transfer process.The actual cause of the noise generated by the noise source is analyzed by the tire modal.The transfer function of different paths is obtained,and the main components that cause noise are locked and optimized.In the optimization process of vehicle rim,the method of combining Solidworks and Abaqus co-simulation and experiment is used to optimize the dynamic stiffness of vehicle rim.The modal analysis method is used to analyze and optimize the vehicle sheet metal parts to solve the road noise problem with prominent frequencies.When analyzing the wind noise of the vehicle,the airtightness of the vehicle is firstly analyzed,and the airtightness test bench is used to investigate the airtightness of the vehicle.Containment optimization is carried out locally,and the air tightness problem of the whole vehicle is finally solved.When the vehicle uses the control variable method to lock the whistle problem in the wind tunnel laboratory,all the air inlets at the front of the vehicle are tested for containment,so as to solve the problem of wind noise during the high-speed driving of the vehicle.In the optimization of vibration and noise of vehicle air conditioning system,its transfer model and noise transfer path are studied.In the semi-anechoic laboratory,the noise of the vehicle air-conditioning system is tested and checked.The external controller is used to lock the gear where the problem noise is located,and the modal characteristics of the pipeline are changed by lengthening the pipeline,so as to avoid the vibration noise from the compressor and the pipeline.Resonance phenomenon occurs when the modal phases of the circuit overlap.The optimization scheme of vehicle NVH performance can not only be used to guide engineering design,but also provide a theoretical basis for the practice of interior noise diagnosis,shortening the research and development cycle of vehicle companies and saving costs.In addition,due to the limitations of the existing technology,it is necessary to make full use of the method of combining simulation and experiment in order to solve the problem better and faster.