Features of Modeling of Microprocessor Protection of a Transformer

The observed trend of introducing digital technologies into the structure of the fuel and energy complex is accompanied by a transition from full-scale testing methods to test methods on the stands of mathematical and semi-natural modeling. Carrying out traditional test methods is impractical, since it does not take into account all the characteristic modes of operation of objects, therefore, consideration of the features of digital differential protection of the transformer is carried out on the basis of a simulation model in the Simulink graphical environment based on Matlab, which provides reproduction of physical objects in the form of mathematical models. The purpose of the study of the proposed model was to determine ways to improve the accuracy of the differential protection settings and ensure the sensitivity of the protection under different operating modes of the transformer. During the study of the model, the features of modeling the protection operation were taken into account, taking into account the nature of the change in the instantaneous differential current in emergency modes, in the modes of overexcitation and the surge of the magnetizing current of the transformer. Based on the results of the research, optimal parameters were selected to prevent excessive triggering of the differential protection of the transformer based on the analysis of the harmonic composition of the current in case of damage.