Optimization technique taking area effect into account for computer-aided insulation design of vacuum circuit breakers

As a computer-aided tool, the electric field calculation has been widely utilized for electrical insulation design of vacuum insulated power equipment like vacuum circuit breakers (VCB) and vacuum interrupters (VI). In this piper, we describe a computer-aided optimization technique of B high voltage electrode contour in the vacuum interrupter to improve the electrical insulation performance. The electrode area effect on vacuum breakdown characteristics as well as electric field distribution is introduced to the optimization process. In order to verify the accuracy and the efficiency of the proposed technique, we applied it into the contour optimization of a main contactor electrode in the vacuum interrupter. We compared the obtained results by the optimization proposed here and the electric field optimization. From the calculation results, we confirmed that the proposed optimization method has higher availability and higher accuracy than the electric field optimization from the view point of improvement of the electrical insulation performance.