Cost-Effective Insulation Coordination Design for 115-kV Transmission Line due to Lightning Back Flashover

This paper presents a cost-effective insulation coordination design for the 115-kV transmission line of EDL (Electricite Du Laos) in Lao PDR (Laos People's Democratic Republic). The design's main objective is to find an insulation coordination model with the minimum total cost. In this paper, PSCAD/EMTDC software has been applied to realize the technical objective, and the total costs of the different transmission line designs using various surge protection options have been calculated. The multi-objective optimization (MOOP) method has been used to select an optimal solution by satisfying both technical and cost objectives. The results reveal that the proposed method can be used to choose the appropriate transmission line design with the reduced back flashover voltage with optimal cost due to lightning for 115-kV overhead transmission lines.