A Techno-Economic Method for Replacing Transformers

A method for developing a more systematic approach to determining the life expectancy of transformers is presented. The approach is based on an economic analysis of the operational characteristics of transformers in conjunction with the technical issues involved in the decision process. Enhanced use is made of the well-known bathtub failure model, including repairs and scheduled maintenance, in order to arrive at a more economically oriented replacement decision. This goal is achieved in part by taking into account the uncertainty inherent in transformer failures and the corresponding interruptions in power. In essence, this technique constitutes a decision support system for determining the life expectancy of a transformer.