Research On Fault Diagnosis Method Of Disconnector In GIS Based On Multi-Sensor Fusion

With the increasing service life of GIS,equipment failures occur frequently,which gradually exposes the shortcomings of GIS in the process of material,design and installation.The disconnector in GIS can be isolated in case of equipment failure to prevent more serious loss.Therefore,it has important practical value to study the fault detection method of disconnector in GIS.This paper analyzes the methods and research status of GIS internal disconnector fault detection at home and abroad,establishes the disconnector Solid Works model,and carries out the finite element analysis by ANSYS,and obtains the fixed frequency and vibration mode of GIS internal disconnector under opening state,intermediate state and closing state.The transmission mechanism model of GIS internal disconnector is established by Adams,and the opening and closing simulation is carried out according to the actual situation,and the travel curve of external crank arm in the process of opening and closing is obtained.Through Ansoft to simulate the opening and closing driving motor,through simulating the three states of no-load,load and normal operation,the current curve change rule in three cases is obtained.According to the above three signals,a fault diagnosis method of GIS internal disconnector based on multi-sensor fusion is proposed.In this paper,a data acquisition device for GIS internal disconnector is developed.The current transformer and magnetic angular displacement sensor are used to collect the winding current signal and the angular displacement signal of the outer crank arm respectively.At the same time,the data monitoring system of upper computer is developed to realize the necessary functions of signal acquisition,storage,processing and display.This paper also developed a vibration signal acquisition device,through the vibration sensor and data acquisition card to measure the vibration signal of GIS moving contact operating room,and through the matching host computer software to store and export the data.In this paper,a DTW(dynamic time warping)algorithm is proposed to analyze the angular displacement data of the external crank arm.This method can dynamically analyze the subtle changes of the angular displacement curve,and greatly reduce the problem of large curve contrast error caused by different acquisition time.In this paper,a method of current curve envelope based on cubic spline interpolation algorithm is proposed.The method can accurately extract the upper and lower envelope of current curve and provide reliable guarantee for analyzing fault current curve.In this paper,a vibration signal processing algorithm based on wavelet packet decomposition and envelope spectrum is proposed.The algorithm can decompose the characteristic frequency of vibration signal,and the fault type can be obtained by comparing with the fault characteristic spectrum.Through the current signal,angular displacement signal and vibration signal,we can accurately judge whether there is fault operation condition and fault type of disconnector in GIS.