Online Voltage Instability Prediction Using Novel Indices from Trajectory of Voltage Profile

Voltage instability is a costly phenomenon, which can lead to vast blackouts in power systems if it is not foreseen and controlled in time. So there is a grave necessity to define and implement indices from power system that can indicate the level of voltage security and possibility of voltage collapse. This task has been facilitated by widespread usage of Phasor Measurement Units (PMUs) in Wide Area Measurement Systems (WAMS). These devices allow the operators to monitor system parameters by synchronized online data acquisition. This paper proposes a novel method for in-time evaluation of voltage stability condition and effective prediction of imminent voltage instability by conducting a fast process on voltage profile data and extraction of cogent indices for assessing voltage security. The proposed method is examined on a modified IEEE39-Bus system and its efficiency is tested in various scenarios.