Improving specification of transformers based on operational experience

A transformer in power system is a critical equipment and availability of this to be maintained at highest reliability. These are used for transferring power at elevated voltages to reduces losses. Failure of transformer jeopardise the utility and customer system and need to be avoided. Offline condition monitoring practices, though well established, fails to predict the failure of transformer. Online condition monitoring to be adopted for real time analysis and knowing the deterioration and in-time corrective actions with planned outages. Transformer failure data of Tata Power for last 10 years are analysed and based on the learning from these, operation and maintenance practiced were improved. The learnings from these failures/repairs were the actionable item for improving specification/design at the time of conceptualisation of new transformer and are presented in the paper.