基于非线性压缩变换的某型航空发动机整机试车排故分析

Fault analysis of an aeroengine test based on nonlinear squeezing time-frequency transform

摘要:

本文基于非线性压缩变换对某型航空发动机整机试车振动信号进行了特征提取与故障诊断。非线性压缩变换由于其幅值无关性,能够增强微弱信号特征的表征能力,同时能够提高时频图的能量聚集性。本文对某型航空发动机进行地面整机试车试验,并通过数据采集装置获取各测点的振动信号,然后利用非线性压缩变换良好的微弱特征表征能力与时频聚集性,并结合其他信号分析方法,对采集到的振动信号进行分析。最终,结合航空发动机的结构与理论知识,实现了对其可能存在故障的排查与猜测,同时验证了非线性压缩变换在航空发动机实际试车振动信号分析中的有效性与实用性。

Abstract:

In this paper, the feature extraction and fault diagnosis of an aeroengine vibration signal are carried out based on nonlinear squeezing time-frequency transform. Nonlinear squeezing time-frequency transform can enhance the characterization of weak signal features because of its amplitude-independence, and it can improve the energy concentration of the time-frequency representation at the same time. In this paper, the ground test of an aeroengine is carried out, and the vibration signals of each measuring point are obtained by the data acquisition device. Then, the vibration signals collected are analyzed by nonlinear squeezing time-frequency transform and other signal analysis methods. Finally, combined with the structure of the aeroengine and the theoretical knowledge, the excluding and guessing of possible fault modes are realized, and the effectiveness and practicability of nonlinear squeezing time-frequency transform in the analysis of the actual aeroengine test signal are verified.