Automatic thermal monitoring on power transformers

In order to take any proper maintenance actions the transformers conditions should be acquired. Since the transformer performance is limited by its main insulation condition, we focus on the thermal monitoring. As the transformer failure statistic rises, the root cause and ways to solve the problem should be found. Based on failure modes and effect analysis overloaded, external disturbances and ambient condition have affected the transformer performance. Due to this complexity, a physical model is the fittest tool to solve the problem. In order to build such a model, automatic thermal monitoring should be developed. The system will record any temperature changes in any single event experienced by the transformer every 5 seconds. Three transformers that have been chosen as the pilot project are coming from 150/20 kV 60 MVA class. In this paper we would like to describe our experiences in installing sensors and developing the thermal modeling.