Risk optimization of power transformer tank and accessories: Practical experiences in Thailand

Risk on relevant costs of power transformer acquisition into the network has been faced by electric utilities. Degraded transformers need a proper maintenance to prolong their in-service lifetime. Tank and accessories of the transformer are a part of major transformer components. Risk evaluation of the transformer tank and accessories is presented with practical experiences in Thailand. Historical failure records of 115/22 kV transformers and 230/115 kV transformers are calculated as the percentage of defective components. Condition and importance of the transformers are assessed. Transformer risk is then recognized by both indices. Finally, the risk can be managed and reduced by this recommended model. Stability and reliability of the system are improved.

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