Effect of micro-fillers in polytetrafluoroethylene insulators on the characteristics of surface discharges in presence of SF6, CO2 and SF6-CO2 mixture

Effect of micro-fillers in polytetrafluoroethylene insulators on the characteristics of surface discharges in presence of SF6, CO2 and SF6-CO2 mixture

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This study is devoted to the optical and electrical characterisation of discharges propagating over insulators made of polytetrafluoroethylene (PTFE) filled with different kinds of micro-mineral fillers immersed in gas or gaseous mixture, under lightning impulse voltage (1.2/50 µs), using a point-plane electrode arrangement. The fillers the authors investigated are MoS2, Al2CoO4, SiO2 and CaF2. The gases and mixture the authors considered are SF6, CO2 and SF6-CO2. It is shown that the stopping length of discharges Lf increases quasi-linearly with the voltage; Lf is shorter in SF6 than in CO2 and it is higher when the point electrode is positive than when it is negative while the initiation voltage of discharges is higher with a negative point than with a positive one. The discharges do not always present a radial structure as reported in the literature. Also, the type of filler greatly influences the characteristics of creeping discharges. In a given gas or mixture, the shortest Lf is obtained with PTFE filled with MoS2 or Al2CoO4. Thus, insulators with these fillers appear as the best insulators.


    1. 1)
    2. 2)
      • C.X. Wang , A. Wilson , M.W. Watte . Surface charge flashover sustained by electrostatic surface charge on epoxy resin insulator in SF6. IEE Proc. A Sci. Meas. Technol. , 5 , 346 - 350
    3. 3)
      • I. Al Bawy , O. Farish . Insulator flashover in SF6 under impulse voltage conditions. IEE Proc. A , 89 - 97
    4. 4)
      • D. Shibutani , H. Naoki , H. Okubo . Impulse creepage discharge propagation mechanisms in N2/SF6 gas mixtures. Trans. Inst. Elect. Eng. Japan , 4 , 455 - 460
    5. 5)
      • Allen, N.L., Tan, B.H.: `Initiation of positive corona on insulator surface', Proc. 12th Int. Symp. on High Voltage Engineering, 2001, Bangalore, India, 3, p. 5–8.
    6. 6)
    7. 7)
    8. 8)
    9. 9)
      • T. Jing . Surface charge accumulation: an inevitable phenomenon in DC GIS. IEEE Trans. Electr. Insul. , 5 , 771 - 778
    10. 10)
      • K.D. Srivastava , J. Zhou . Surface charging and flashover of spacers in SF6 under impulse voltages. IEEE Trans. Electr. Insul. , 3 , 428 - 442
    11. 11)
      • K. Nakanishi , A. Yoshioka , Y. Shibuya , T. Nitta . (1982) Charge accumulation on spacer surface at DC stress in compressed SF6 gas, Dielectrics gaseous.
    12. 12)
      • H. Fujinami , T. Takuma , M. Yashima , T. Kawamoto . Mechanism and effect of DC charge accumulation on SF6 gas insulated spacers. IEEE Trans. Electr. Insul. , 333 - 340
    13. 13)
      • A. Knecht . (1982) Development of surface charge accumulation on epoxy resin spacers stressed with direct applied voltage, Dielectrics gaseous.
    14. 14)
      • Fouracre, R.A., Twema, F.A., MacGregor, S.J., Given, M.J.: `The influence of charge on surface flashover', Eleventh Int. Symp. on High Voltage Engineering, 1999, 3, p. 329–332, no. 467.
    15. 15)
      • Gallimbertti, I., Marchesi, I., Niemeyer, L.: `Streamer corona at an insulating surface', Proc. Seventh Int. Symp. on High Voltage Engineering, 1991, Dresden, Germany, p. 1–4.
    16. 16)
      • N.L. Allen , A.A.R. Hashem . The role of negative ions in the propagation of discharges across insulating surfaces. J. Phys. D. Appl. Phys. , 2551 - 2557
    17. 17)
      • S. Sato , W.S. Zaengl , A. Knecht . A numerical analysis of accumulated surface charge on DC epoxy resin spacer. IEEE Trans. Electr. Insul. , 333 - 340
    18. 18)
      • Jing, T., Morshuis, P.H.F.: `Evaluation of field-steering techniques in GIS with respect to surface charge accumulation', Proc. Fourth Int. Conf. on Conduction and Breakdown in Solid Dielectrics, 1992, Sestri Levante, Italy, p. 102–106.
    19. 19)
      • Coulibaly, M.L., Beroual, A., Aitken, O., Girodet, A.: `Experimental characterization of creeping discharges over solid/gas and solid gaseous mixture interfaces under lightning impulse voltage', Sixteenth Int. Conf. on Gas Discharges and Their applications, 7–12 September 2008, Cardiff, Wales, UK.
    20. 20)
      • Coulibaly, M.L., Beroual, A., Aitken, O., Girodet, A.: `Investigation on creeping discharges propagating over insulators immersed in gases and gas mixtures under lightning impulse voltage', Int. Conf. on High Voltage Engineering and Application, 9–12 November 2008, Chongqing, China.
    21. 21)
      • A. Beroual , M.L. Coulibaly , O. Aitken , A. Girodet . Investigation on creeping discharges propagating over epoxy resin and glass insulators in presence of different gases and mixtures. Eur. Phys. J. – Appl. Phys. , 3
    22. 22)
      • A.S. Pilla , R. Hackam . Modification of electric field at the solid insulator vacuum interface arising from surface charges on the solid insulator. J. Appl. Phys. , 1302 - 1313
    23. 23)
      • C. Laurent . Diélectriques solides et charges d'espace. Tech. l'Ingénieur, Traité d'électricité D2305 , 1 - 13
    24. 24)
    25. 25)
    26. 26)
      • L. Kebbabi , A. Beroual . Optical and electrical investigations on creeping discharges over solid/liquid interface under lightning impulse voltage. IEEE Trans. Dielectr. Electri. Insul. , 3 , 565 - 571
    27. 27)
      • L. Kebbabi , A. Beroual . Influence of solid insulating thickness on the morphology of creeping discharges propagating over solid/liquid interfaces – Fractal analysis. J. Phys. D Appl. Phys. , 177 - 183
    28. 28)
      • Coulibaly, L.: `Characterisation of creeping discharges propagating over solid/gas interface – relation between materials properties and fractal dimension', 2009, PhD, University of Lyon France, Ecole Centrale de Lyon.
    29. 29)
      • I. Fofana , M. Farzaneh . A simplified model for simulation of corona discharge development on an ice surface. IEEE CEIDP, Boulder, Colorado (USA) , 667 - 670
    30. 30)
      • L. Niemeyer , F. Pinnekamp . Leader discharges in SF6. J. Phys. D Appl. Phys. , 1031 - 1045
    31. 31)
      • K. Miyoshi , Y.W. Chung . (1993) Surface diagnostics in tribology, fundamental principles and applications, series on modern tribology.

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