Development of asset management support tools for oil-immersed transformer

Decision support tools (PC programs) for creating a maintenance strategy for electric power equipment based on the asset management technique are being very intensively developed in Japan to reduce maintenance costs. In this paper, two programs for an oil immersed transformer based on the evaluation of the life-cycle cost are presented. One provides the optimum overhaul timing and expense by considering the repair cost for oil leakage from the main body and the overhaul effect. The other provides the optimum overhaul strategy by considering the oil leakage probability and replacement cost of transformer accessories, such as bushings and a conservator. These programs have been demonstrated by referring to actual maintenance data of one Japanese utility. Other utility companies can examine which strategies are better with their own data.