Research On Virtual Order Analyzer For Rotating Machinery

Order analysis is one of the most important techniques of rotating machinery involving vibration signal processing and fault diagnosis. Rotating machinery vibration includes stationary vibration and non-stationary vibration, which include important characteristic information that can reflect work-state of rotating machinery. It is important to inspection and diagnosis of setting. Up to now, most methods based on traditional FFT often used are very good at analyzing stationary vibration of rotating machinery, but not suitable for non-stationary vibration characteristics analysis to some extend. However the appearance of order analysis can resolve the problem well. The technique will be studied in this paper.The existing order tracking technologies in the world nowadays are introduced, and computational order tracking based on conic fitting is studied and implemented. Order tracking technology is one of the most important areas of order analysis. In the paper, by comparing with many kinds of order tracking technologies and considering the fact of the task and the characteristic of the virtual instrument, the order resampling times is computed through conic fitting and the resample is come true through interpolation filter, so the angular signal is achieved and the order tracking is succeed.The zero-phase digital filtering for avoiding order aliasing is studied and implemented. The tracking filtering for avoiding order aliasing always adopts the digital filter bank. In the paper, by studying the filtering for avoiding order aliasing, the zero-phase digital filtering for avoiding order aliasing is proposed.Computing method of rotating speed based on first order digital differential is proposed in the paper and Smoothing the speed curve through the piecewise least square technique with cubic spine curve fit which eliminates the errors and faults of computing rotating speed in the first time that brings up by tacho pulses destroyed. So precision of rotating speed computation is largely improved.The order spectrum and STFT time-frequency spectrum are studied and implemented. In the order analysis, there are two kinds of spectrum analysis technologies: two-dimensional spectrum analysis and three-dimensional spectrum analysis (namely spectrum map). The order spectrum is the main method of two-dimensional spectrum analysis, and the three-dimensional spectrum analysis includes time-frequency spectrum and speed-order spectrum. Through spectrum...