Open AccessIdentification of measuring part elements of numerical relay protection by its response time
Author(s) -
Mikhail Andreev,
Aleksey Suvorov,
Vladimir Rudnik
Publication year - 2020
Publication title -
vestnik irkutskogo gosudarstvennogo tehničeskogo universiteta
Language(s) - English
Resource type - Journals
eISSN - 2500-1590
pISSN - 1814-3520
DOI - 10.21285/1814-3520-2020-5-1030-1040
Subject(s) - relay , microprocessor , digital protective relay , control theory (sociology) , converters , computer science , signal (programming language) , electronic engineering , electronic circuit , protective relay , voltage , engineering , electrical engineering , computer hardware , control (management) , power (physics) , physics , quantum mechanics , artificial intelligence , programming language
The purpose of the study is to develop an identification method of a specific implementation of the elements of the measuring part (intermediate converters, analog filters) and partially computational-logical part (digital filters) of a microprocessor relay protection by the signal actuation time, which, unlike the existing approaches allows to identify and exclude the delays introduced by the executive protection elements. The method of directed graphs is used to form a mathematical model of the measuring part of the microprocessor relay protection. The solution formed as a result of differential equations is implemented using the method of analog implicit continuous integration. The time delays introduced by the input protection circuits are determined as follows: identical signals are fed to the terminal and the mathematical model of protection; signal actuation time is recorded, where the time starting point is the moment the input signal reaches the setpoint and the end point is the moment of the actuation signal occurrence. Having studied 144 different combinations of measuring part elements (intermediate converters, analog filters) and digital filters with a finite impulse response of microprocessor relay protection, the most “optimal” combination has been chosen, which features the least deviation from the response time of a real device in all studied modes as compared with other combinations. The proposed identification method of input circuit elements of microprocessor (numerical) protection is the main way to bring the model closer to a real device. It also enables to receive a table of “typical” response times of protections with the different structure of the measuring part and depending on the specific type of protection terminal choose in practice a predetermined “optimal” internal composition of protection used when setting up protection using their mathematical models.