汽车间歇性抖动机理及评价方法讨论  

Discussion of the Mechanism and Evaluation Method of Automobile Intermittent Shake

作　　者：王金立 WANG Jinli(Anhui Jianghuai Automobile Group Co.,Ltd.,Anhui Hefei 230022)

机构地区：[1]安徽江淮汽车集团股份有限公司,安徽合肥230022

出　　处：《汽车实用技术》2022年第1期55-60,共6页Automobile Applied Technology

摘　　要：文章讨论了车辆出现间歇性抖动现象、命名,间歇性抖动表现的频率是动力总成悬置悬置的刚体模态频率,而不是转速的半阶次或燃烧的半阶次。分析了间歇性抖动的机理、主要的传递路径,如果发动机燃烧标定控制异常或开发过程中未关注燃烧稳定性会导致发动机出现失火现象,包括燃烧不良或多缸失火现象,这是间歇性抖动的根本原因。最后讨论了对燃烧稳定性影响较大的喷油控制、进气控制、点火控制等标定参数,给出了常用的燃烧稳定性指标及推荐限值。讨论了整车间隙性抖动的评价方法,包括飞轮端角加速度、座椅振动峰值系数和振动计量值等参数。最后结合某1.5 T发动机匹配整车出现的间歇性抖动问题,调查发现该发动机喷油控制中的EOIT角度控制对燃烧影响较大,原始标定数据的燃烧稳定性参数均低于推荐限值,EOIT由上止点前65度优化为上止点前85度,燃烧稳定性参数满足燃烧稳定性限值,异常频段振动幅值由10 mg降低到2.5 mg,降幅达到75%,解决了车内间歇性振动问题且整车排放满足排放法规要求。This article discusses the phenomenon and naming of the intermittent shake of the vehicle.The frequency of the intermittent shake is the rigid body modal frequency of the power train mount,not the half-order of the speed or the half-order of the combustion.The mechanism of intermittent shake and the main transmission path are analyzed.If the engine combustion calibration control is abnormal or the combustion stability is not attended during the calibration development process,it will cause the engine to abnormal combustion,including poor combustion or multi-cylinders misfire,which is the root cause of intermittent shake.Finally,the calibration parameters such as fuel injection control,intake control,and ignition control that have a greater impact on combustion stability are discussed,and commonly used combustion stability indicators and recommended limits are given.Discussed the evaluation method of vehicle intermittent shake,including parameters such as flywheel end angular acceleration,seat vibration peak coefficient and vibration dose value.Finally,combined with the intermittent shake problem of a 1.5 T engine matching a vehicle,the investigation found that the EOIT angle control in the fuel injection control of the engine has a greater impact on the combustion.The combustion stability parameters of the original calibration data are all lower than the recommended limit,optimized EOIT from 65 BDTC to 85 degrees BDTC,the combustion stability parameter meets the combustion stability limit,and the vibration amplitude of the abnormal frequency band is reduced from 10 mg to 2.5 mg,and the drop rate reaches 75%,which solves the intermittent shake of the car.and meet the requirements of emission regulations.

关 键 词：间歇性抖动 间歇性抖动机理 燃烧稳定性 喷油截止时刻 振动计量值 

分 类 号：U464[机械工程—车辆工程]