Electrical Engineering

, Volume 94, Issue 1, pp 37–48

Detection of electric treeing of solid dielectrics with the method of acoustic emission

Open Access
Original Paper


The paper presents results of research of electrical treeing of solid dielectrics with the method of acoustic emission (AE). The study was performed with an alternating voltage of 50 Hz in the range up to 21 kV (RMS) on methyl polymethacrylate or crosslinked polyethylene samples. They were of cuboidal shape of the dimensions 25 × 10 × 4 mm. One of the cuboid sample walls of the dimensions 25 × 4 mm was covered with a conducting paint. On the opposite wall, a surgical needle of T-25 type was screwed. The distance between the electrodes (the needle and the wall covered with a conducting paint) was in the range 0.5–2.0 mm. Registered signals were denoised with wavelet transformation method and then there were analyzed. The following parameters were analyzed: a sum and rate of acoustic emission counting, a sum and rate of acoustic emission events, RMS value of the electric signal leaving the converter. Spectrum and spectrogram were also analyzed. It was found that AE signals are generated during electrical treeing of solid dielectrics. Values of chosen parameters increased their values when the process begins. There are also some dominant frequencies ranges, different for different kinds of dielectrics, connected with the treeing.


Acoustic emission Electrical treeing Electrical insulation Solid dielectrics 


  1. 1.
    Białasiewicz J (2004) Wavelets and approximations. WNT, Warszawa (in Polish)Google Scholar
  2. 2.
    Ding H-Z, Varlow BR (2005) Thermodynamic model for electrical tree propagation kinetics in combined electrical andmechanical stresses. IEEE Trans Dielectr Electr Insulation 12(1):81–89CrossRefGoogle Scholar
  3. 3.
    Dissado LA (2002) Understanding electrical trees in solids: from experiment to theory. IEEE Trans Dielectr Electr Insulation 9(4):483–497CrossRefGoogle Scholar
  4. 4.
    Dissado LA, Dodd SJ, Champion JV, Williams PI, Alison JM (1997) Propagation of electrical tree structures in solid polymeric insulation. IEEE Trans Dielectr Electr Insulation 4(3): 259–279CrossRefGoogle Scholar
  5. 5.
    Dobrzycki A (2008) Acoustic emission method in analysis and measurement of electrical treeing process in a strong electric field. Doctoral thesis, Poznan (in Polish)Google Scholar
  6. 6.
    Dobrzycki A, Opydo W (2007) An attempt to appraise the progress of methyl polymethacrylate degradation induced by a strong electric field on the grounds of analysis of acoustic signal emission, vol 56. Poznan University of Technology Academic Journals, Poznan, pp 197–203Google Scholar
  7. 7.
    Dobrzycki A, Opydo W, Dobroszewski R (2006) Computer-aided analysis of acoustic emission signals accompanying methyl polymetacrylate degradation in a strong electric field, vol 52. Poznan University of Technology Academic Journals, Poznan, pp 201–210Google Scholar
  8. 8.
    Documentation of R3α transducer. PAC, Princeton (2002)Google Scholar
  9. 9.
    Imai K (2002) Properties of tree propagation from a simulated tree channel. In: Proceedings of IEEE 2002 annual report conference on electrical insulation and dielectric phenomena. IEEE, pp 963–966Google Scholar
  10. 10.
    Kaneiwa H, Suzuoki Y, Mizutani T (2001) Characteristics of partial discharges in artificial simulated tree channels during tree propagation. IEEE Trans Dielectr Electr Insulation 8(1):843–848CrossRefGoogle Scholar
  11. 11.
    Kaneiwa H, Suzuoki Y, Mizutani T (2000) Partial discharge characteristics and tree inception in artificial simulated tree channels. IEEE Trans Dielectr Electr Insulation 7(6):72–77CrossRefGoogle Scholar
  12. 12.
    Kudo K (1998) Fractal analysis of electrical trees. IEEE Trans Dielectr Electr Insulation 5(5):713–726CrossRefGoogle Scholar
  13. 13.
    Lyons RG (2006) Understanding digital signal processing. WKiŁ, Warszawa (in Polish)Google Scholar
  14. 14.
    Uehara H, Kudo K (2005) Temporal propagation characteristics of simulation tree considering growth probability. In: Proceedings of 2005 international symposium on electrical insulating. Kitakyushu, Japan, pp 17–20Google Scholar

Copyright information

© The Author(s) 2011

Authors and Affiliations

  1. 1.Institute of Electrical Engineering and ElectronicsPoznan University of TechnologyPoznanPoland

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