Desenvolvimento e implementação de um sistema dedicado para diagnóstico de falhas em transformadores de distribuição

Abstract

It is estimated that millions of operations involving open-type fuse cutouts are performed annually so as to allow the replacement of transforms in which the primary protection worked as a result of internal or external faults. In this scenario, the operator cannot visually identify the type and location of a fault. To overcome this situation, the operator changes the faulty fuse link tail for another one that is faster and supports less current. Two possible consequences to this approach is that i) fuses can explode causing safety issues by spreading fragments and ii) transformers can spill out hot oil and thus polluting the environment and harm the operator. Electricity company statistics show that transformer explosion corresponds to 5 porcentage of the total events and can cause property damage and risk to human beings. In this thesis, a new electronic prototype for testing power transformers is proposed and developed. Both theoretical and practical contributions are made toward the problem solution and to the development of a compact and portable prototype that will be used to diagnose live transformers without disconnecting the secondary coil from the electricity source.