Voltage stability indices: Formulation and classification perspectives

Abstract

Voltage instability had been observed as the foremost cause of blackout incidents worldwide in last three decades. In order to deploy an appropriate countermeasure and enhance voltage stability margin, voltage stability predictor is of utmost importance. Therefore, much research had been focussed to propose voltage stability indices (VSIs) that can identify weak areas and overall condition of power systems. In this paper systematic review covering imperative aspects of formulation theory, expressions, critical values and applicability of VSIs has been presented in chronological order. A broad categorization of VSIs is also addressed. An inclusive review provides a strong foundation for further research in the perspective of voltage stability evaluation for real-time control applications.