Digital protection of the transformer with a capacity of 40 MVA of the «Pivdenno-Skhidna» substation «Kirovogradoblenergo»
Students Name: Okuskov Taras Anatoliiovych
Qualification Level: magister
Speciality: Electrical Energetics, Electrical Engineering and Electromechanics
Institute: Institute of Power Engineering and Control Systems
Mode of Study: full
Academic Year: 2023-2024 н.р.
Language of Defence: ukrainian
Abstract: PrJSC "Kirovogradoblenergo" is a private company headquartered in the city of Kropyvnytskyi. It is engaged in the distribution of electricity in the Kirovohrad region. A power transformer is an integral part of any substation, although in general they are made of high-quality materials and are subjected to strict tests before commissioning, so the requirements for their protection must also be serious. In addition to classic protection against external (mechanical) damage, the most modern technologies of relay protection are also used, which allow to ensure its uninterrupted operation, protect against disturbances that may occur in the electrical network, as well as against internal damage caused by natural processes of aging or untimely maintenance [1, 2, 3]. According to the task, during the work on the master’s qualification project, I will characterize the power district, perform a study of transformer damage and protection against them, and present transformer relay protection schemes [4]. The object of the research is the existing substation "Pivdenno-Skhidna" of PJSC "Kirovogradoblenergo". The subject of the study is digital protection and automation of the 40 MVA transformer of the South-Eastern substation. The purpose of the implementation is to calculate the operation parameters of the digital protection of the transformer based on the digital terminal of the HITACHI - ABB RET670 concern. The master’s qualification work provides information on the location, a single line diagram of the Pivdenno-Skhidna substation of Kirovogradoblenergo PJSC and the technical characteristics of the main electrical equipment of the substation. 8 The paper considered the main types of transformer damage and special modes of operation of networks of the studied voltage classes. The features of differential, current and gas protection of the transformer are also considered [1, 5]. Also, information is given about the features of relay protection and automation made on a digital basis, the advantages of digital devices, their accuracy and speed of operation are indicated. The general characteristics and main functions of the HITACHI-ABB RET-670 digital terminal, which is used for protection and automation of all types of transformers and shunt reactors, are given. Typical configurations and functions implemented in them are considered. The typical configuration of the "A05" terminal was selected, the set of functions of which allows to implement all the necessary protections and automation of the 40 MVA transformer of the 150/35/10kV substation "South-East". The main control and management functions of the digital terminal were also given [5]. With the help of the "DAKAR" software complex, the calculation of short-circuit currents (short-circuit currents) on the high-voltage (HV), medium-voltage (МV) and low-voltage (LV) sides of the transformer was performed for the maximum and minimum modes of short-circuit currents. The results of the calculations were used during the calculation of transformer protection and automation [3]. For the configuration of the digital terminal, appropriate tables with parameters and settings of protection and automation activations were created.