摘要
针对柴油机气门故障诊断问题,在柴油机上模拟了气门间隙异常、气门漏气故障,同步测取了正常和故障情况下的缸盖振动与瞬时转速信号,提出了基于阶比跟踪的振动信号等角度重采样方法,准确地实现了振动信号时间域到角度域的转换,避免了频谱泄漏及混叠。考虑到缸盖振动信号的非平稳特性,应用经验模态分解法将振动信号分解成一系列具有不同尺度的内禀模态函数,利用三维Hilbert谱提取了反映柴油机故障的特征参数。试验结果表明:研究方法可以有效地提取柴油机振动信号的故障特征,从而实现柴油机配气机构故障诊断。
According to diagnosis of diesel engine valve faults, abnormal valve clearance and leakage were mimicked on a diesel engine, and cylinder head vibration signal and transient speed signal were measured synchronously on normal and fault valve conditions respectively. In order to avoid the leakage and aliasing of the frequent spectrum of the vibration signal, re-sampling method based on order tracking was proposed so that the vibration signal was transformed from time domain to crank angle domain accurately. Owing to its unsteadiness, the vibration signal was converted into a series of intrinsic mode functions with different scales using the empirical mode decomposition, and the parameters of the fault features were extracted by 3D Hilbert spectrums. Experimental results show that the feature extraction proposed in this study can effectively obtain the fault features of the vibration signal caused by valve faults of diesel engines, which can be used to realize the diagnosis of the valve system faults of a diesel engine.
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2016年第2期145-150,共6页
Chinese Internal Combustion Engine Engineering
基金
国家自然科学基金青年科学基金项目(51509051)
黑龙江省自然科学基金项目(E2015049)
