Weak fault characteristic extraction based on steady holographic-order spectrum

A steady holographic-order spectrum method was presented and used to extract weak fault characteristics of speed-varying signal of a gear box.Firstly,the influence of rotating speed fluctuation on the precision of the traditional order method was analyzed,and an improved order method based on rotating speed adjustment was constructed,the improved order spectrum of horizontal and vertical speed-varying signals was analyzed with the holographic spectrum,a steady holographic-order spectrum was constructed,and compared to the traditional order analysis result of a single test point's signal.Test results showed that the improved order spectrum can restrain the influence of rotating speed fluctuation on the equal angle sampling and improve the precision of order analysis,so the steadiness of holographic-order spectrum is enhanced efficiently;compared with order spectrum of a single measurement point in horizontal or vertical direction,the steady holographic-order spectrum can be used not only to analyze a speed-varying signal,but also fuse the information of different points,and the steady holographic-order spectrum's quantified parameters can estimate the technical status of the object to be diagnosed more accurately.It was proved that the steady holographic-order spectrum is an effective method to extract weak fault characteristics in a speed-varying signal.