Invetrer Scroll Compressor Vibration Signal Analysis

In recent years, the inverter scroll compressor has been widely applied in the airconditioning and refrigeration, compressed air, engine turbo, booster pump and other fields.Their working performance of the system is directly related to the work of the quality ofoperation, and the vibration parameters is a measure of an important indicator of the inverterscroll compressor performance analysis of vibration signal processing is a very importantaspect of the entire compressor test system.The inverter scroll compressor, small vibration,low noise, working frequency changes with the different work conditions and change, coupledwith some noise interference, makes the inverter scroll compressor of vibration signalfrequency analysis than general rotating machinery complex much, and traditional thesesignal processing method has been difficult to achieve the ideal effect.This subject in combination of the inverter scroll compressor vibration characteristics,the wavelet packet theory is widely applied in the current engineering signal processing, it canfinish decomposing to the low-frequency part and high-frequency part, and has a moresophisticated local analysis ability to complete the per-treatment of the vibration signal of theinverter scroll compressor. Based on the wavelet packet to deal with the noise of the twodifficulty of the key analysis, the first is the threshold function selection, proposes a newapplication in the speech signal processing is improved threshold function, and its denoisingresult were compared with the traditional threshold denoising function. The second is thequantification of the threshold value, detailed of the four thresholding rules, and through theMatlab wavelet packet tools function and the simulation signal, for the four kinds of rules doa comparative analysis. Draw to use the kind of improved wavelet packet threshold functioncan achieve better de-noising effects. In order to complete the inverter scroll compressor faultsignal envelope extraction, this paper introduced EMD method through Hilbert spectra andHilbert marginal chart to judge fault frequency, then complete fault signal diagnosis.Through the above two kinds of theory in different occasions successful example ofapplication, which both up applied to inverter scroll compressor vibration signal analysis,solve the compressor in the signal of post processing, easy to put the low frequency part(useful signal) ignore, also easy to put the high frequency part of signal (fault component) asnoise removal of a series of problems, and to the judgement of the performance and faultdiagnosis of the better effect. Finally, the measured signal, using Matlab software simulationanalysis go verify the above theory.