前端轮系振动引起的压缩机啸叫分析与优化

Analysis and Optimization of Air-compressor’s Whistle Caused by Vibration of Front End Accessory Drive Systems

振动噪声控制是前端轮系开发中的关键技术,对于轮系附件振动引起的噪声问题,行业内缺乏系统和实践研究。以某BSG(Belt-Driven Starter Generator)混动车型出现的空调压缩机啸叫问题为研究对象,通过压缩机台架试验、冷媒压力脉动分析和整车路径排查,确定噪声主要由压缩机激励皮带和轮系附件模态所致,并通过发动机悬置和车身传递到车内;结合模态测试和仿真手段,提出有效的工程化方案,方案实施后啸叫阶次降低15 dB以上,车内声品质得到明显改善。在解决问题的同时,为前端轮系附件的NVH设计,提供很好的工程实践经验。

The vibration and noise control is a key technology in the development of front end accessory drive(FEAD)of automobiles. However, there is few systematic and practical research of the noise caused by vibration of FEAD in the automobile industry. In this paper, the air-compressor whistle problem of a belt-driven starter generator(BSG) in hybrid assembly vehicles is studied. Through the bench test of the air-compressor, the analysis of refrigerant pressure pulsation and investigation of transmission path, it is determined that the whistle noise is mainly caused by the transverse vibration of the serpentine belt excited by the air conditioning compressor, which further amplifies the vibration of the accessory modes of the FEAD. By means of modal test and simulation, an effective engineering solution strategy is proposed. After the implement of the strategy, the whistling noise is reduced by 15 dB and the interior sound quality has been improved significantly. This work has provided a good engineering practical experience and a guidance for the FEAD NVH design.