Integral equation method for the computation of PD inception voltage in voids

The presence of voids in insulation materials has deleterious effects on the electrical performance of insulation, and eventually cause breakdown of the insulation. Understanding the physics of partial discharge is a major field of research for the interpretation and identification of insulation defects. The integral equation method presented in this paper provides a general approach to computations of electric stress in dielectrics with voids. The applications of the method are illustrated by computations of the maximum electric stress and inception voltage for voids of various shapes. The method presented in this paper allows us to analyze the electric stress in dielectrics with voids, and thus to make assessment of the risk of insulation breakdown.