The Characteristics and Growth Mechanisms of Demetallization due to Self Healing on MPPF for Capacitor Applications

  • Published : 2004.06.01

Abstract

In order to help understand the growth mechanisms of demetallization due to self healing on a metallized polypropylene film (MPPF), several types of defects affecting the breakdown of capacitor dielectrics were made. The breakdown voltages with dielectric thickness were measured at self healing and the demetallized area was evaluated for all of the self healing events. The shapes and growth processes of the demetallized spots on the dielectrics were investigated. As a result, self healing mainly occurred at pin tips, wrinkle sides, and junctions of the wrinkles, and the breakdown voltages strongly depended on the thickness of the dielectrics. In addition, the demetallized area due to self healing was governed by the breakdown voltage and it has been mainly grown by some factors; the applied voltage; the consequent self healing events taking place at the circumference of the original self healing spots; the conductive paths formed by two or more self healing spots and by the consequent self healing spots.

Keywords

References

  1. C. W. Reed and S.W. Cichanowski, 'The Fundamentals of Aging in HV Polymer-film Capacitors,' IEEE Trans. on Dielectrics and Electrical Insulation, vol.1, no.5, pp.904-922, Oct. 1994
  2. 'Technical Trend of Capacitor Films,' OHM, pp.36-40, Oct. 1998
  3. R. Bartnikas and R.M. Eichhorn, Engineering Dielectrics-Electrical Properties of Solid Insulating Materials : Molecular Structure and Electrical Behavior, ASTM Special Technical Publication, vol.lI A, pp.505-509, 1983
  4. D.G. Shaw, S.W. Cichanowski and A. Yializis, 'A Changing Capacitor Technology-Failure Mechanisms and Design Innovations,' IEEE Trans. on Electrical Insulation, vol.EI-16, no.5, pp. 399-412, Oct. 1981
  5. S. Tandon, Modelling of Stresses in Cylindrically Wound Capacitors : Characterization and the Influence of Stress on Dielectric Breakdown of Polymeric Film, Ph.D. dissertation, University of Massachusettes Amherst, USA, pp.3-8, Sep. 1997
  6. Y. Muramoto, M. Nagao and M. Kosaki, 'Self-healing breakdown of polyimide thin films in the cryogenic temperature region,' 13th. International Cryogenic Engineering Conference, vol.35, no.11, pp.791-793, 1995
  7. Y. Yoshida and T. Muraoka, 'The Development of High Voltage Power Capacitor Technology in Japan,' IEEE Electrical Insulation Magazine, vol.11, no.1, pp. 32-45, Jan./Feb. 1995
  8. Y. Yoshida and M. Nishimatsu, 'Power Capacitors,' IEEE Trans. on Electrical Insulation, vol.EI-21, no.6, pp. 963-973, Dec. 1986
  9. K.S. Kim, 'The Manufacture Technology in Power Condenser,' Monthly of Electrical Technology, pp.65-69, Nov. 1999