摘要
针对柴油机气门间隙故障诊断问题,在WP7柴油机上模拟了多种气门间隙故障,测取了正常及故障条件下的缸盖振动信号。考虑柴油机缸盖振动信号具有非平稳的特点,提出一种基于局部均值分解边际谱和马氏距离的故障诊断方法。该方法在LMD边际谱的基础上定义了频率中心,并以此作为柴油机气门间隙的故障特征,利用马氏距离判断柴油机气门的工作状态。试验结果表明:该方法可以有效地提取柴油机气门间隙故障特征,实现柴油机气门机构故障诊断。
For diagnosis of diesel engine valve clearance fault, several valve clearance faults were simu- lated in model WP7 diesel engine, and cylinder head vibration signals were measured in normal and fault con- ditions. In view of non-stationary characteristics of diesel engine cylinder head vibratiofa signals, a fault diag- nosis method based on local mean decomposition （LMD） marginal spectrum and Mahalanobis distance was proposed. In the method frequency center was defined based on the LMD marginal spectrum, using Mahal- anobis distance method as fault features for judging diesel engine valve operation condition. Experimental results show that the method can effectively extract diesel engine valve clearance fault features and use them in fault identification.
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2014年第6期96-100,共5页
Chinese Internal Combustion Engine Engineering
基金
国家自然科学基金重点项目(U1233201)
国家"八六三"高技术研究发展计划项目(2012AA1117064)
关键词
内燃机
柴油机
气门间隙
局部均值分解
边际谱
马氏距离
IC engine
diesel engine
valve clearance
local mean decomposition（LMD）
marginal spectrum
Mahalanobis distance
