柴油机表面低频振动的状态空间重构及其应用

State Space Reconstruction of Surface Low Frequency Vibration of Vehicle Diesel and Its Application

提出了由实测柴油机表面振动加速度信号经变换再用于状态空间重构的预处理过程,结合典型实测信号说明了此处理过程的分析方法用于诊断的情况。先对表面振动加速度信号进行积分和滤波,求得适用于特定分析目的的表面低频振动位移序列,通过对此序列的分析确定合适的重构参数,并据此重构了系统的状态空间,对正常情况和两种简单故障情况下的重构空间进行相图分析、最大Lyapunov指数分析、主成分分析,给出了相应结果。分析结果表明,基于低频振动位移重构状态空间的分析方法能够比较直观、清晰地区分正常状态和两种简单的故障状态。

The process of reconstructing state space based on transforms of originally measured vibration acceleration data of a diesel engine was studied. Examples were given to show the application of this process to the analysis and fault diagnosis of the diesel. Displacement sequences of low frequency vibration were formed by integrating and filtering the acceleration sequences, which is suitable for special analysis purpose. Then, state space was reconstructed based on each displacement sequence. The results of phase plane analysis, of maximal Lyapunov exponent analysis and of principal component analysis(PCA)were given with explanations. The results clearly discriminate among some simple technical conditions of the engine.