Optimized models for overload monitoring of power transformers in real time moisture migration model

In this paper a mathematical model, based on experimentation, to estimate the axial moisture distribution in power transformer windings was developed. The model considers the variables of moisture content in oil, top oil temperature, as well as the transformer´s design parameters and ageing of the insulation system. The model was validated using a small-scale experimental setup, which represents a 75 MVA transformer. The developed model proved to be more accurate than existing models. It considers the axial moisture distribution in paper, in 4 thermal zones equidistantly distributed along the height of the winding. This paper compares the results of the proposed model with those provided by other authors.