摘要
插电混合动力汽车的纯怠速工况,与传动汽车怠速有所不同,几乎完全无负载,可能会存在间歇性低频抖动问题,严重影响驾乘舒适性。首先提出间歇性指数来评价抖动的间歇性水平。进而对车内振动、发动机振动、转速波动和发动机缸内燃烧压力进行了全面测试及分析。综合利用时频分析,相关性分析和燃烧稳定性分析来识别间歇性抖动原因。研究表明,车内的间歇性抖动是由发动机的转速波动和燃烧稳定性差引起。通过优化发动机VVT参数,可以明显改善整车间歇性抖动,间歇性指数改善了40%,主观感受较好,达到优化目标。
The pure idle condition of plug-in hybrid electric vehicle(PHEV)is different from that of traditional vehicle.There’s little load for the pure idle condition of PHEV,so it might cause low-frequency fitful idle shake,which would affect the driving comfort.The fitful index is proposed to evaluate the shake.Then the vehicle vibration,engine vibration,engine speed fluctuation and combustion pressure are tested and analyzed.Then the time-frequency analysis,relevant analysis and combustion stability analysis are conducted to identify the source of the fitful shake.The study reveals some conclusions.The fitful shake of vehicle is caused by the terrible speed fluctuation and combustion stability.The optimization of VVT angle could improve the fitful shake by 40%.
作者
相龙洋
顾彦
鲜敏
Xiang Longyang;Gu Yan;Xian Min(Vehicle Integration Department,Technical Center of SAIC Motor,Shanghai 201804)
出处
《汽车实用技术》
2019年第11期75-77,共3页
Automobile Applied Technology
关键词
低频怠速抖动
间歇性指数
缸内压力
燃烧稳定性
VVT优化
low-frequency idle shake
fitful index
engine pressure
combustion stability
VVT optimization
