Electric Field Distributions in Laser Drilled Voids of Polymeric Test Samples

Future electric transportation systems are expected to employ electrical power trains with higher operating voltage and power density. Therefore, compact and reliable insulation systems are important, since they influence the system integration, thermal resistance, and parasitic inductance. In this paper, experiments and analysis show behavior which are not observed with mechanically produced holes before. A boundary element analysis of the electric field distribution around the voids reveals why these new observations are identified in voids with relatively sharp corners. The electric field computation shows conditions under which there is electric field enhancement at the void periphery. This drives the partial discharge (PD) activity and the erosion growth away from the center of the voids.