Análisis de la trayectoria de la impedancia de falla vista por el relé de distancia en sistemas eléctricos ante oscilaciones de potencia

Abstract

The rejection and entry of large blocks of load, sudden departures or disconnections of lines, entry and rejection of generating plants cause alterations in the power flow, therefore, these effects cause a modification in the angles of the synchronous machines, causing power oscillations. . The impact of power swings on electrical systems can be devastating and show weak spots in large electrical systems, so oscillating systems must be dissociated so that the rest of the electrical system maintains stability. Likewise, power oscillations can affect the protection zones of the distance relay due to waves at different frequencies, which alter the voltage and current magnitudes of the electrical system and this can erroneously open the transmission lines. The programming of the distance protection relays against oscillatory events has a function that allows the impedance path to be analyzed, thus enabling the blocking or opening of the electrical transmission lines. Therefore, the objective of this article is to analyze the power oscillations when the center of the oscillation of the electrical system is located on the transmission line and, in turn, how the impedance trajectory appears when it enters the protection zone. of the distance relay through laboratory simulations.