The Research Of Method Improving The Accuracy Of Holosepctrum Analysis For Rotating Machinery

Holospectrum analysis is one of the most important techniques of rotating machinery involving vibration signal processing and fault diagnosis. Currently, vibration signal analysis based on FFT can basically meet the need of usual fault signature abstraction and fault analysis, and can not meet the need of accurate diagnosis and complicated fault diagnosis because of not utilizing the phase information of vibration signal affectively. Holospectrum is just developed under this condition. Making full use of the amplitude,frequency and phase information of the horizontal and vertical channels of one or several sections, therefore,Holospectrum technology can identify and diagnose the concealed fault signature more accurately than general methods. Therefore, Holospectrum technology is set to the research object. Its contributions list as follows:â‘ When the speed pulse signal is provided, a calculation of the speed curve is achieved using first order digital differential method and the lease square of five points three times smoothing approach.â‘¡A new method of holospectrum based on zoom spectrum and correction of phase difference is put forward against to the lower precision of traditional holospectrum in intensive spectrum environment. First, it takes selected band zoom method, using multiple analytical band-pass filter, in order to conduct zoom analysis on the interval, which the center of is order frequency, and then the impact of intensive spectrum can be eliminated by increasing the frequency resolution. With correction of phase difference for the max peak, the amplitude and phase of each order frequency can be acquired. At the last, the holospectrum is synthesized. Through the simulation and the analysis of flexible rotor's vibration signal, the result shows that it has higher precision in practice and can diagnose the rotation machinery fault more accurately and more effectively.â‘¢In the study of purification filter to original orbits signal, against non-stationary feature of orbits signal, taking into account of frequency domain localization properties of harmonic wavelet, use the harmonic wavelet to refine and decompose frequency band ,extract the data points of target band, reconstruct signal and synthesize orbit. Experiments show the harmonic wavelet has the advantages and feasibility in non-stationary signals filtering. â‘£Finally, a holospectrum analysis systems for rotating machinery is developed, with VC++ as the development platform. This system has friendly interface and is operated easy. Experiment result shows that this system can effectively extract and analyze characteristic information of vibration signal in rotating machinery.