Reliability Supporting of Relay Protection for 110kV Transmission Line with High-load and Short-distance in a Ring Network

Abstract

As part of its mandate to meet the increasing electricity demands of Ulaanbaatar while ensuring uninterrupted, reliable, and high-quality energy supply, the National Power Transmission Grid (NPTG) takes on the responsibility of expanding, revamping, and maintaining power transmission infrastructure, including lines, substations, and equipment. In order to enhance overall reliability, this expansion necessitates seamless integration of old and new systems. Implementing advanced technical solutions becomes imperative in order to meet these challenges. The city center, newly developed residential areas, and major consumers have been strategically located in close proximity to new transmission and distribution substations. As a result of 110 kV high-load circuit networks connecting these substations, a critical issue relates to the selectivity of short-distance lines. A relay protection solution has been explored for 110 kV high-load short-distance lines in this research, and its impact on the dynamic stability of the power system has been evaluated.