Development of risk optimization model for high voltage substation transformer maintenance

Perfected maintenance strategies of power transformer in high voltage transmission system with improved reliability in the power system and reduced maintenance cost are required by electric utilities. Risk optimization model for maintaining the transformer is developed by a combination of transformer condition and network characteristic with applied scoring and weighting approach. Electrical and oil tests are collected and analyzed for the condition assessment, whereas operating characteristics of the transformer are gathered and calculated for the network assessment. To set up the recommended maintenance zones, the network index is higher weighted than the condition index. The transformer with high risk level is selected first for the maintenance action. The risk faced by the utilities is then managed by the proposed risk optimization model to achieve improved stability and reliability of the power system.