Summarized Diagnostic Parameter for Condition Assessment of Power Transformer Windings Insulation

To determine parameter fit for diagnosing power transformer windings insulation condition, heat-mass exchange processes are studied in power transformers turn insulation based on the mathematical model considering windings parameters change caused by changes in the moisture content, temperature and pressure. The analysis of the process of heat and moisture transfer in the insulation of windings of the power transformer on the basis of differential equations and the generalized kinetics equation of changes in the volume of insulation of the windings with a minimum number of constants. Based on the diagnostic parameter, it is possible to predict the residual insulation life of the extremely loaded equipment of traction transformer substations by the dynamics of moisture content and, consequently, the further operation of the transformer or the need for its repair.