A Novel Index for Detecting Line Stability Based on the Structural Characteristics of Power Transmission Systems

Abstract

In general, there is a large mismatch between power generation and power demand. Hence to ensure the power quality of power transmission systems has become a challenging task. One major issue in power quality is voltage collapse, which can cause system blackout if not detected in time. There are many measures to detect voltage collapse, among which identification of weak buses and weak lines plays a major role. Weak buses are identified using the Structural Characteristics Method (SCM). A novel stability index based on network structural characteristics is proposed for the identification of weak lines that can cause voltage collapse. This Electrical Distance Stability Index (EDSI) is determined on the basis of the electrical distance between various buses with that of weak buses determined by a structural characteristics method. The major significance of SCM and EDSI is the determination of weak buses and weak lines respectively without the need for load flow analysis unlike the existing methods. The proposed index is implemented on IEEE 6, 14 and 30 bus systems. The results thus obtained by the EDSI are identical and effective when compared with the results of existing line stability indices.