Column: Transformer maintenance

Column: Transformer maintenance

Vol. 5 Issue 3

Health indices and life assessment methodology

Myth, fake maintenance or genuine contribution to transformers fleet reliability?



Nowadays, trendy attempts to avoid transformer failures include life assessment programs, software and health indices. Although many efforts are invested in these approaches, the transformer failure rate is not significantly reduced. This article will highlight the main critical points that have to be taken into consideration when index and life assessment is concepted and evaluated. The more details are taken into consideration and the more deeply they are treated, the more representative and accurate the health index will be. An accurate health index is probably the best maintenance strategy to have for a large transformer fleet, and it may be ingrained in the mind of any human interdisciplinary expert, or in the code of an artificial intelligence software.

Keywords: health index, maintenance, life assessment

  1. Introduction

Transformers are a very important piece of equipment, vital and crucial for the functioning of a modern society. As the population and industrialization growth impose the use of higher voltage and higher power, with units occupying less room and using fewer insulation materials, modern transformer design is in many aspects quite different to transformers made 20 years ago.

In the post-privatization era, the redundancy of transformers has decreased substantially, so in case of a transformer failure, the impact for the final customer or stakeholder has grown bigger. The cost of power transformer monitoring and maintenance has become negligible in comparison to the cost of failure consequences. Transformer owners and engineers are willing to understand the failure mechanism, mainly to avoid a huge cost of power outage and eliminate replacement or repairing intervals, while papers, brochures and academic research on power transformer maintenance, survey and life assessments have become best-selling literature and preferred conference subjects.