变速工况下采煤机行星齿轮传动系统故障诊断

Fault diagnosis method of shearer planetary gear transmission system under variable speed conditions

采煤机截割煤层时,牵引部行星齿轮传动系统处于变速工况,且行星齿轮传动系统结构复杂,导致振动信号存在多种调制现象,影响行星齿轮传动系统故障特征提取。针对上述问题,将阶次分析技术与包络谱相结合,提出了一种基于包络阶次谱分析的采煤机行星齿轮传动系统故障诊断方法。首先对行星齿轮传动系统的非平稳时域振动信号进行Hilbert包络分析,然后将非平稳时域包络信号进行计算阶次跟踪处理,转换为等角度的角域信号,最后对等角度角域信号进行快速傅里叶变换,得到信号的包络阶次谱。对该方法进行了仿真分析及基于动力传动故障诊断综合试验台的变速工况下行星齿轮传动系统故障诊断试验,结果表明:对于变速工况下的振动调制信号,阶次分析难以提取特征阶次,而包络阶次谱分析方法可有效提取其特征阶次,并实现了行星齿轮传动系统故障准确诊断。

When the shearer cuts the coal seam,the planetary gear transmission system of the traction unit is in a variable speed working condition,and the structure of the planetary gear transmission system is complicated.This leads to a variety of modulation phenomena of vibration signals,which affects the extraction of fault characteristics of the planetary gear transmission system.In order to solve the above problems,a fault diagnosis method of shearer planetary gear transmission system based on envelope order spectrum analysis is proposed by combining order analysis technique with envelope spectrum.Firstly,the method performs Hilbert envelope analysis on the non-stationary time-domain vibration signal of the planetary gear transmission system.Secondly,the method performs computed order tracking on the non-stationary time-domain envelope signal,converts it into equal angle angular domain signal.Finally,the method performs the fast Fourier transform on the equal angle angular domain signal to obtain the envelope order spectrum of the signal.The simulation analysis of this method and the fault diagnosis test of planetary gear transmission system under variable speed conditions based on the comprehensive test bed for power transmission fault diagnosis are carried out.The results show that it is difficult for the order analysis to extract the characteristic order for the vibration modulation signal under variable speed conditions.However,the envelope order spectrum analysis method can extract the characteristic order effectively and realize the accurate fault diagnosis of planetary gear transmission system.