Instruments and Systems: Monitoring, Control, and Diagnostics Annotation << Back New Directions in Traditional Methods of Transformer Insulation Testing D.A. KUROV, S.E. STEPANOV The processes of degradation of insulation of windings of current-carrying parts of power transformers, electric machines, apparatus and electrical equipment are considered. The analysis of traditional methods of testing and evaluating the state of isolation of transformers by applying a constant voltage is presented. The main reasons and errors of changing the insulation parameters during temperature fluctuations are revealed. A new methodology for analyzing the measurement of frequency characteristics of dielectrics is proposed, which makes it possible to adequately and accurately convert the results of the evaluation of insulation parameters in the frequency range as a function of temperature. The results of the research are implemented in systems and devices for complex diagnostics of substation equipment transformers. Keywords: transformer, diagnosis of DC, the insulation of the windings, the system, apparatus, method of measurement of parameters of frequency characteristics of dielectrics. DOI: 10.25791/pribor.03.2020.1156 Pp. 09-14.