Electricity plays a significantly important role in the life of the present day man. Nowadays it is present in all areas of our lives, its use has become exceptionally extensive. We only notice the presence of electric energy, if its continuity ceases. We need to produce electric energy to the consumers’ current claims continuously, because the technology storing the recquired quantity of electricity is not available yet.
To insure the continuous supply of customers we need main equipments, which are reilable and their potential breakdown can be foreseen, with these we can avoid breakdowns with big losses and damage. In order to define the working states of the equipments on the electric energy network detailed diagnostic measurements are needed These diagnostic examinations survey the electric network elements nondestructively, and most of the examinations can be performed on the spot.
My thesis’ primary aim was to present the diagnostic examinations of distribution transformers. The power transformers are indispensable elements of the electric energy system. The state of influences the safety of the full system to a great extent.
In the first part of my thesis, after briefly describing the electric network, I present the function and the role that transformers play in the electric network. It will be evaluated by the help of standards, literature, measurements, different mistakes, and in total with the definition of their general state.
In the second, and the main part of my thesis, after the theoretical section the examinations performed on transformers in practice are reviewed. Three measurements of distribution transformers, that I got from ELMŰ Network Ltd. Diagnostic group, show well the various examinations, what kind of mistakes can be found in the insulation and in the mechanics state.
Finally I outline shortly the health index of transformer evaluating system. I compare it with other systems, that describe general state. After all I show other oppurtunities to develop and refine the system.