Open AccessLONGITUDINAL IMPEDANCE OF A SINGLE-CIRCUIT POWER TRANSMISSION LINE WITH TWO LIGHTNING PROTECTION CABLES IN THE PROBLEM OF REMOTE FAULT LOCATION
Author(s) -
Evgeniya A. Panova,
AUTHOR_ID
Publication year - 2021
Publication title -
vestnik ûžno-uralʹskogo gosudarstvennogo universiteta. seriâ ènergetika/vestnik ûžno-uralʹskogo gosudarstvennogo universiteta. seriâ, ènergetika
Language(s) - English
Resource type - Journals
eISSN - 2409-1057
pISSN - 1990-8512
DOI - 10.14529/power210405
Subject(s) - electric power transmission , fault (geology) , transmission line , electrical engineering , electrical impedance , lightning (connector) , power (physics) , short circuit , ground , line (geometry) , equivalent circuit , power transmission , lightning strike , relay , engineering , voltage , physics , geometry , mathematics , geology , quantum mechanics , seismology
One of the most important tasks in remote fault location in a 110 kV+ network is modeling the power lines taking into account the electromagnetic and electrostatic interaction of their conductive elements. A common approach is to use the mathematical models recommended by the guidelines for calculating short-circuit currents for relay protection. However, these models of power transmission lines take into account the geometric mean distance between the wires and the lightning protection cables, which means they average the values of the mutual induction impedances. In cases where wires and cables are located asymmetrically relative to each other, this leads to an overestimation of the zero-sequence impedance of power lines and, as a consequence, to an underestimation of the single-phase short-circuit current. This situation can affect the results of remote fault location. To eliminate this drawback, the article proposes a combined equivalent circuit for a single-circuit power transmission line with two lightning protection cables, based on a combination of methods of phase coordinates and symmetric components. The given equivalent circuit of power transmission lines allows calcula¬ting the mode parameters using the method of symmetric components and, at the same time, simulating those of interest for calculating power lines using phase coordinates.