Classification and separation of partial discharge signals by means of their auto-correlation function evaluation

This paper describes a K-Means Clustering classification algorithm for the separation of Partial Discharge (PD) signals and pulsating noise due to multiple sources occurring in practical objects. It is based on the comparison of the Auto-Correlation Function (ACF) of the recorded signals assuming that the same source can generate signals having similar ACF while ACF differ when signals with different shapes are compared. The ACF has been selected for its capability of well summarize both time- and frequency-dependent features of the signals. A correlation index that presents the best compromise between strong and weak discrimination among pulses, has been selected out of different distance measurements. The final result of the algorithm is a set of classes containing signals having similar shape which can be processed successively for signal source identification. Meaningful applications of the proposed algorithm are also reported. Improvements in separation effectiveness can enhance the clearness of the PD patterns and, consequently, the quality of the defect identification.

[1]  J. MacQueen Some methods for classification and analysis of multivariate observations , 1967 .

[2]  Michael J. Kurtz,et al.  Experience with PDA diagnostic testing on hydraulic generators , 1988 .

[3]  W. Krause,et al.  Advanced suppression of stochastic pulse shaped partial discharge disturbances , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[4]  Jitka Fuhr Procedure for identification and localization of dangerous PD sources in power transformers , 2005 .

[5]  G. Stone,et al.  Propagation of Partial Discharge and Noise Pulses in Turbine Generators , 1986, IEEE Transactions on Energy Conversion.

[6]  Alfredo Contin,et al.  Use of a mixed-Weibull distribution for the identification of PD phenomena [corrected version] , 1995 .

[7]  A. Cavallini,et al.  A new methodology for the identification of PD in electrical apparatus: properties and applications , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[8]  Yasuo Suzuoki,et al.  Model for partial discharges associated with treeing breakdown: II. tree growth affected by PDs , 2000 .

[9]  M. Pompili,et al.  PD pulse burst characteristics of transformer oils , 2006, IEEE Transactions on Power Delivery.

[10]  C. Hudon,et al.  Partial discharge signal interpretation for generator diagnostics , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[11]  G. Montanari,et al.  Digital detection and fuzzy classification of partial discharge signals , 2002 .

[12]  A. J. Schwab,et al.  Modelling of partial discharge development in electrical tree channels , 2003 .

[13]  J. Devins The physics of partial discharges in solid dielectrics , 1984, Conference on Electrical Insulation & Dielectric Phenomena - Annual Report 1984.

[14]  A. Cavallini,et al.  Experience on partial discharge monitoring of power transformers , 2004, Conference Record of the 2004 IEEE International Symposium on Electrical Insulation.

[15]  Alfredo Contin,et al.  Partial Discharge cross-talk recognition in rotating machines by pulse-shape analysis: preliminary results , 2003, Proceedings: Electrical Insulation Conference and Electrical Manufacturing and Coil Winding Technology Conference (Cat. No.03CH37480).

[16]  Johan J. Smit,et al.  Standardization of on-line VHF PD measurements on turbo generators , 2002 .

[17]  G. Stone,et al.  Propagation of Partial Discharge and Noise Pulses in Turbine Generators , 1986, IEEE Power Engineering Review.

[18]  R. Bartnikas,et al.  Dielectric Electrode Surface Effects on Atmospheric Pressure Glow Discharges in Helium , 2007, IEEE Transactions on Plasma Science.

[19]  Massimo Pompili,et al.  Simultaneous ultrawide and narrowband detection of PD pulses in dielectric liquids , 1998 .

[20]  Yasuo Suzuoki,et al.  A novel physical model for partial discharge in narrow channels , 1999 .

[21]  T. Okamoto,et al.  Auto-correlation function of PD pulses under electrical treeing degradation , 1995 .

[22]  P. Morshuis,et al.  Partial discharges at DC voltage: their mechanism, detection and analysis , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[23]  A. Pemen,et al.  Propagation of partial discharge signals in stator windings of turbine generators , 2006, IEEE Transactions on Energy Conversion.

[24]  J. Devins,et al.  The 1984 J. B. Whitehead Memorial Lecture the Physics of Partial Discharges in Solid Dielectrics , 1984, IEEE Transactions on Electrical Insulation.

[25]  A. Cavallini,et al.  Analysis of partial discharge phenomena in paper-oil insulation systems as a basis for risk assessment evaluation , 2005, IEEE International Conference on Dielectric Liquids, 2005. ICDL 2005..

[26]  Massimo Pompili,et al.  Characteristics of the partial discharge pulse burst in transformer and switchgear oils , 2002, Proceedings of 2002 IEEE 14th International Conference on Dielectric Liquids. ICDL 2002 (Cat. No.02CH37319).

[27]  R. Bartnikas,et al.  Spark-to-glow discharge transition due to increased surface conductivity on epoxy resin specimens , 1993 .

[28]  Magdy M. A. Salama,et al.  Fuzzy logic applied to PD pattern classification , 2000 .

[29]  B. Yazici,et al.  Statistical pattern analysis of partial discharge measurements for quality assessment of insulation systems in high-voltage electrical machinery , 2004, IEEE Transactions on Industry Applications.

[30]  Alfredo Contin,et al.  Advanced PD inference in on-field measurements. II. Identification of defects in solid insulation systems , 2003 .

[31]  A. Cavallini,et al.  PD detection in extruded power cables: an approximate propagation model , 2008, IEEE Transactions on Dielectrics and Electrical Insulation.

[32]  J. Densley,et al.  Fundamentals of partial discharge in the context of field cable testing , 2000 .

[33]  R. E. James,et al.  Interpretation of Partial Discharge Quantities as Measured at the Terminals of HV Power Transformers , 1986, IEEE Transactions on Electrical Insulation.

[34]  K. D. Srivastava,et al.  Review of condition assessment of power transformers in service , 2002 .

[35]  Richard O. Duda,et al.  Pattern classification and scene analysis , 1974, A Wiley-Interscience publication.

[36]  Magdy M. A. Salama,et al.  Discrimination between PD pulse shapes using different neural network paradigms , 1994 .

[37]  R. Bartnikas,et al.  On the spark to pseudoglow and glow transition mechanism and discharge detectability , 1992 .

[38]  H. Okubo,et al.  A novel technique for partial discharge and breakdown investigation based on current pulse waveform analysis , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[39]  H.-G. Kranz,et al.  Fundamentals in computer aided PD processing, PD pattern recognition and automated diagnosis in GIS , 2000 .

[40]  E. Kuffel,et al.  Activity of moving metallic particles in prebreakdown state in GIS , 1997 .

[41]  M. Salama,et al.  PD pattern recognition with neural networks using the multilayer perceptron technique , 1993 .

[42]  Yasuo Suzuoki,et al.  The contribution of discharge area variation to partial discharge patterns in disc-voids , 2004 .

[43]  Alfredo Contin,et al.  Advanced PD inference in on-field measurements. I. Noise rejection , 2003 .

[44]  Junya Suehiro,et al.  PD characteristics and mechanisms in artificial air-filled voids at room and liquid nitrogen temperatures , 1999 .

[45]  D. W. Gross,et al.  Phase resolving partial discharge pattern acquisition and frequency spectrum analysis , 1994, Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM).

[46]  G. C. Stone,et al.  Application of partial discharge testing to motor and generator stator winding maintenance , 1994 .

[47]  Hitoshi Okubo,et al.  The relationship between partial discharge current pulse waveforms and physical mechanisms , 2002 .

[48]  A. Cavallini,et al.  A fuzzy logic algorithm to detect electrical trees in polymeric insulation systems , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[49]  P.T.M. Vaessen,et al.  A new frequency response analysis method for power transformers , 1992 .

[50]  Z.-I. Kawasaki,et al.  Toward automatic classification of partial discharge sources with neural networks , 2006, IEEE Transactions on Power Delivery.

[51]  Mors Assessment of Dielectric Degradation by Ultrawide-band PD Detection , 2004 .

[52]  A. Cavallini,et al.  PD inference for the early detection of electrical treeing in insulation systems , 2004, IEEE Transactions on Dielectrics and Electrical Insulation.

[53]  Magdy M. A. Salama,et al.  Neural network system using the multi-layer perceptron technique for the recognition of PD pulse shapes due to cavities and electrical trees , 1995 .

[54]  R. Plath,et al.  Synchronous 3-Phase Partial Discharge Detection on Rotating Machines , 2005 .

[55]  T. Okamoto,et al.  Contribution of surface conductivity to the current forms of partial discharges in voids , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.

[56]  A. Friedman Foundations of modern analysis , 1970 .

[57]  D. Wenzel,et al.  Separation of partial discharges from pulse-shaped noise signals with the help of neural networks , 1995 .

[58]  Frédéric de Coulon,et al.  Signal theory and processing , 1986 .

[59]  K. Kimura,et al.  New noise rejection techniques on pulse-by-pulse basis for on-line partial discharge measurement of turbine generators , 1996 .

[60]  Y. Suzuoki,et al.  /spl phi/-q-n patterns and current shapes of partial discharges in void , 1998, Proceedings of 1998 International Symposium on Electrical Insulating Materials. 1998 Asian International Conference on Dielectrics and Electrical Insulation. 30th Symposium on Electrical Insulating Ma.

[61]  R. Bartnikas,et al.  Effect of dielectric surfaces on the nature of partial discharges , 2000 .

[62]  Yasuo Suzuoki,et al.  Model for partial discharges associated with treeing breakdown: I. PDs in tree channels , 2000 .

[63]  G.C. Montanari,et al.  Partial discharge inference by an advanced system. Analysis of online measurements performed on hydrogenerator , 2004, IEEE Transactions on Energy Conversion.

[64]  L. Niemeyer A generalized approach to partial discharge modeling , 1995 .

[65]  Gian Carlo Montanari,et al.  Random sampling and data processing for PD-pulse height and shape analysis , 2000 .

[66]  A. Cavallini,et al.  Diagnosis of EHV and HV Transformers Through an Innovative Technique: Perspectives for Asset Management , 2008, Conference Record of the 2008 IEEE International Symposium on Electrical Insulation.

[67]  T. Kurihara,et al.  Particle-triggered pre-breakdown phenomena in atmospheric air gap under AC voltage , 2005, IEEE Transactions on Dielectrics and Electrical Insulation.