Partial discharge. XI. Limitations to PD as a diagnostic for deterioration and remaining life

For pt.X see ibid., vol.8, no.1, p.16 (1992). The correlation of partial discharge (PD) measurements with insulation degradation and failure is addressed. The limitations inherent to such diagnostics as applied to solid insulating systems are examined. The discussion is based on simple experimental facts and the physics of discharge within solid dielectrics. It is concluded that meaningful evaluation of PD measurements in terms of the rate of degradation or remaining life is impossible in the absence of a microscopic description of the defect.<>