Effect of the Interfacial Pressure and Electrode Gap on the Breakdown Strength of Various Qielectric: Interfaces

Absired: Electrical breakdown at the interface of two dlielectric surfaces is a major design consideration in unde~grournd cable accessories. Our previous studies have shown that the dlielectric strength of greased and aon-greased interfaeer can be greatly affected by their surface conditions as well as their substrate material There observations were made in both lalboratory molded sampler and real cable joints. The present paper deals with the effect of the interfacial pressure and electrode gap on the breakdown strength of various molded dielectric interfaces. Results showed that greased and "greased interfaces have each a distinct behavior in both parameten examined. Finally. a plot of the breakdown voltage as a function of the product of pressure and gap was introduced and reems to give a more appropriate representation of both effects.