To the choice of the principle functioning diagnostic system of digital substations

Diagnosis substations has an important role in their operation. Current diagnostic methods are directed to troubleshooting individual elements of electrical substations. At the same time, development of modern intelligent technologies made possible the complex simulation of complex technical systems, including digital substations. This fact allows upgrading a method of natural-model tests for the diagnosis of the state of digital substations. The method of natural-model tests uses experimental data to obtain an adequate model of the object. The model in this paper proposes the use of an approach based on the Petri nets creating a graphical model of an electrical substation and identifying the location of the fault. An example of the implementation of an electrical substation model based on the proposed approach is provided. A generalized algorithm for setting up a model based on the natural-model approach is offered.