Reduction of breakdown appearance by automatic geometry optimization

The paper describes the procedure for the reduction of the breakdown appearance in HV apparatus by automatic geometry optimization. Such procedure consists basically of three main steps: field analysis, breakdown criteria evaluation and geometry optimization. The evaluation of the breakdown criteria is briefly elaborated and illustrated at some well-known "two-sphere" examples. As the accurate analysis of electrical field in complex engineering apparatus is of the essential importance, we briefly present an accelerated boundary element method used for a field analysis. As a final step, an automatic geometry optimization is performed resulting at the end in an optimal geometry with the minimal "maximal" field stresses on the interfaces. This optimal geometry is obtained through an iterative procedure following the non-parametric non-gradient optimization strategy. Finally, the above procedures are illustrated at the design of the generator circuit breaker components.