MODELING THE OPERATION OF 110 kV BUSBAR SECTION DIFFERENTIAL PROTECTION BASED ON A MICROPROCESSOR-BASED DEVICE

Abstract

Ensuring a reliable power supply for a production process is impossible without the uninterrupted operation of power system components. The current trend toward increasing power consumption in the electrical grid infrastructure of metallurgical enterprises increases the probability of higher short-circuit currents, which, in turn, may lead to non-selective operation of busbar differential protection. At present, there is a growing trend toward the use of microprocessor-based devices in the modernization of relay protection and automation systems. For example, digital substations are being implemented, and new types of current transformers are being introduced. At the same time, microprocessor-based devices are economically advantageous because they offer a high availability factor and short operating time. Objectives. The research is aimed at developing a model of the logic part of busbar differential protection based on the BE2704 terminal manufactured by EKRA Research and Production Enterprise LLC. Methods Applied. A specialized domestic software package has been used to develop a mathematical model of various operating modes of the busbar differential protection. A comparative analysis has been performed using parameters recorded by a terminal operating in an actual power system to verify the functionality and accuracy of the differential protection algorithms. Originality. The novelty of the study lies in modeling the operation of busbar differential protection using BE2704 terminals under the conditions of a specific substation to assess the correctness of protection operation during faults, as well as in using the obtained results to configure protection terminals and train personnel. Result. A model of the busbar differential protection of the BE2704 terminal manufactured by EKRA Research and Production Enterprise LLC has been developed and analyzed. The adequacy of the model has been confirmed by comparing the simulation results with actual oscillograms of protection operation. Optimal parameters of the differential protection for the 110 kV busbar sections have been determined, ensuring maximum sensitivity and selectivity with minimum operating time. Practical Relevance. The model makes it possible to verify the connection diagrams, operating algorithms, and setting parameters of the BE2704 terminal at the 110/35/6 kV Taganay substation. This eliminates errors during the implementation and commissioning of equipment at the substation and reduces commissioning time. Analysis of various operating modes of busbar differential protection algorithms has made it possible to identify fundamental errors at the algorithm development stage and take measures to eliminate them, thereby reducing the time required to implement the equipment under development.