MATHEMATICAL MODELING OF THE PROCESS OF DIAGNOSTICS OF THE TECHNICAL CONDITION OF TRANSFORMER INSULATION USING PETRI NETS

Abstract

"In this paper, we have expanded the possibilities of using Petri nets for modeling the process of technical diagnostics. A structural and mathematical model of a system for monitoring diagnostic signs and diagnosing the current state of insulation of transformer substations is proposed, which will allow monitoring the technical condition provided that the parameter values are close to the limit indicators, which, in turn, will classify the results obtained into three classes: normal operation, damage to the turn and interphase insulation of transformer substations. Verification of the obtained results of the implementation of the presented model was carried out and it was found that the diagnostics of the current state of the insulation of these transformers was performed quite effectively with constant monitoring of certain diagnostic parameters with an average absolute deviation rate within 6.19-7.11%, however, in the case when the value of the maximum the deviation indicator during implementation will be more than ±11%, then it becomes necessary to take into account additional parameters that affect the quality of the maintenance process and operation of electrical equipment in the future, for example, the design of transformers and unfavorable conditions for their operation. The analysis of the implementation results made it possible to determine the quality of the developed model, which was controlled by two indicators, namely, the time of the diagnostics, which averaged 0.024 sec., and a fairly good agreement between the results of its implementation with the standard (93.46%), which led to its recommendation when monitoring the current state of the insulation of transformer substations. Also, the software implementation of the obtained model will provide real-time monitoring of diagnostic indicators and will allow determining the residual life of transformers in the event of a possible damage to the turn and interphase insulation more efficiently by about 20% of possible analogues, thereby ensuring a reduction in the number of occurrences of uncontrolled emergencies and a decrease in hourly, material and energy losses."