Trends in the development of the theory of relay protection
The article discusses the main trends in the development of the theory of relay protection. The author adheres to the opinion that the criterion for the correct development of any theory of relay protection can only be the degree of improvement of its main indicators: sensitivity with guaranteed selectivity of the relay protection device. For this purpose, the article introduces the new terms that necessary for operating with the developed methods and presenting already existing concepts in a new light. The simulation model of the protected object becomes the "teacher" of the relay protection algorithm, designed to make a decision on shutdown in damage modes within the protected zone (controlled modes) and not to make such a decision in normal operation and in damage modes outside the protected area (alternative modes). In the basis of the concepts introduced, the modes of operation of an energy facility exist in the multidimensional space of the variable parameters of its simulation model (object space), and they have to be recognized in the multidimensional space of available information parameters (setting space): currents, voltages, etc. In conclusion, it was concluded that as a technical system, relay protection is in constant development. The process of development of a technical system obeys general laws, on the basis of which it is possible to build a theory. The proposed theory of multidimensional relay protection seems to most accurately describe the current trends in the development of relay protection and automation as a technical system.