Avaliação da performance térmica e do posicionamento de sensores de fibra ótica em transformadores de potência por meio de simulações CFD.

Abstract

The internal temperatures and the ability to dissipate the heat from active part influence the windings’ insulation deterioration and determine how long power transformers are able to remain in operation. Due to the great importance of this equipment for the electrical system, studies to avoid failures and ealy aging are needed. This work presents an evaluation of thermal perfomance of power transformers and the optical fiber sensor positioning to tem perature monitoring. For this, experimental results of a power transformer under ODAN (Oil Direct and Air Natural) cooling conditions with 20 optical fiber sensors along its windings were compared with CFD simulations results performed on ANSYS FLuent. It was verified that the puctual temperature measured by optical sensores my not accurately represent the critical temperatures along transformers’ windings, and the windings’ arrangements impact on oil flow and temperature distribution, as the number and positioning of block washers being necessary to be considered in previous studies for a better positioning of the sensors and temperature monitoring.