Neoenergia develops new technology for maintenance of power transformers


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With the new tool it is possible to monitor the quality of the insulating oil of the equipment with a detection system for the presence of moisture in the oil from the microwave, in an automated way

Neoenergia has developed an unprecedented tool to automate maintenance activities for power transformers in distribution substations. The new solution allows real-time monitoring of the quality of the insulating oil with a detection system based on microwaves, in real time.  The purpose is to make the processes more agile and safer, a process which today is carried out through the manual collection of material for analysis in the laboratory. The project is part of the Research and Development (R&D) Program, regulated by the National Electric Energy Agency (Aneel).

“Aligning safety and innovation, which are core values for the group, the project seeks to continue improving the quality of services provided to our customers. The new system brings a substantial gain in the maintenance actions of power transformers, the main asset in our substations, as it enables real-time and automated monitoring of the equipment's integrity, helping to anticipate failures and increase the useful life of our assets", states the R&D project manager, Paulo Gomes.

A prototype was developed to collect, detect and analyze moisture levels in insulating oils using microwaves. The presence of moisture can compromise the equipment's integrity and, therefore, the solution contributes to increase the transformer's useful life. The tool is attached to the equipment, being able to carry out the analyzes according to the frequency defined by the operation and maintenance technicians.

The solution is more accurate than existing sensors on the market as it does not require analysis beyond what can be done in real time by the tool itself, while the techniques already in use today require manual collection, transport and laboratory analysis.

“The equipment is easy to install and programmable. Being able to choose the frequency of sample collection according to the age of the transformer, without human interference, and having the result in real time are the great differentials of this project, as it will allow for more effective monitoring, allowing advance decision-making aimed at safety and asset preservation", explains Flávio Borja, the project's engineer.

The prototypes were tested in eight Celpe transformers, a distributor of Neoenergia in Pernambuco. The research resulted in the submission of two patents: one for the moisture detection system in insulating mineral oil through microwaves and another for the probe that collects the samples. The project was carried out in partnership with the Federal University of Juiz de Fora (UFJF) and LUPA Tecnologia.​

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