Optimization of Corona Ring Design for Composite Insulator Strings

A corona ring on an insulator string on a transmission line is one of the solutions to reduce the electric field stress surrounding the energized end of the insulator string. However, to reduce the electric field magnitude on an insulator string with an optimum design is a challenging task. An optimization methods; Gravitational Search Algorithm and Imperialist Competitive Algorithm were proposed in this work. An insulator string model geometry with a corona ring was modeled in a finite element analysis software. The electric field distribution was evaluated using variation of corona ring dimensions, i.e. the ring diameter, the ring tube diameter and the vertical position of the ring along the insulator string. The insulator string with a corona ring design shows the minimum electric field magnitude using optimization techniques. Hence, this indicates the capability of the proposed methods in achieving an optimum design of a corona ring on an insulator string.