柴油机振动是一种多振源的复杂振动形式,其机体表面振动是内部各种激振力共同作用的综合反映。在柴油机使用过程中技术状态的改变将导致激振力发生不同的变化,因此测量机体激振信号有利于对柴油机技术状态进行监测。通过测量不同技术状态的柴油机机体振动信号,利用小波包分析的方法,将柴油机振动信号按其特征频率进行了小波分解和重构,提取了振动信号特征。分析结果表明,此方法能够提高信噪比,提取的振动信号特征能够反映柴油机技术状态的变化。 Diesel engine vibration is a complex form of vibration of multiple sources, the body surface vibration is a comprehensive reflection of the various internal excitation force. In the process of using diesel engine technology status changes will lead to different exciting excitation force changes, so the body vibration signal is conducive to the technical status of diesel engine monitoring. By measuring the vibration signals of diesel engines in different technical states and using wavelet packet analysis, the vibration signal of diesel engine is decomposed and reconstructed by its characteristic frequency according to its characteristic frequency. The analysis results show that this method can improve the signal-to-noise ratio and the extracted vibration signal characteristics can reflect the change of diesel engine technology state.