汽车怠速间歇性异常抖动研究

Study of intermittent abnormal shake of vehicle idle condition

汽车在怠速工况,间歇性异常抖动会严重影响驾乘舒适性。针对该问题,对车辆的振动特性、转速波动和发动机内部燃烧参数进行了全面测试。基于间歇性异常抖动特征对发动机的转速波动、进气压力,喷油量和点火提前角进行了详细的对比分析。综合利用时域分析、频谱分析和角度域分析相结合的方法来识别异常抖动原因。研究表明,发动机内部的进气压力,喷油量和点火提前角控制不稳定,在一段时间内波动较大,引起发动机瞬态转速的波动,进而引起车内的一阶异常抖动的间歇性变化。建议对发动机燃烧稳定性进行优化来改善该问题。

The intermittent abnormal shake of the automobile under idle condition significantly affects the driving comfort.The vehicle vibration and combustion behavior of the engine are tested and analyzed, including the engine speed fluctuation,inlet air pressure, oil injection and the ignition angle. Then the time domain analysis, spectral analysis and angle domain analysis are used to identify the source of theabnormal shake. The study reveals some conclusions. The inlet air pressure,oil injection and ignition angle are unsteady during a period of time so that the engine rotation speed fluctuate intermittently.Then the vibration of 1 storder of the engine and seat fluctuate accordingly. It is advised that the burning stabilityoptimization of the engine be used to improve this problem.