Prediction of Voltage Collapse in Power System using Different Indices

After some damaging blackouts, voltage stability and collapse have become more concerned problems. This paper analyzes voltage stability indices, named L index and Modal Analysis, which determines the weakest node of the system. From these indicators, it is allowed to predict the voltage instability or the proximity of the system to a voltage collapse. The advantage of the method lies in simple and fast numerical calculations. Through these indicators of voltage stability, it is easy to find the most vulnerable area in a power system. Performance of these indices are also compared in this paper. The computation of indices is done in MATLAB environment and evaluated on IEEE 6 bus, IEEE 14 bus and IEEE 30 bus system, considering various operating conditions and line outages.