Assessment of Voltage Stability Using Network Equivalent

Abstract

In this paper a fast system voltage stability index (FSVSI) has been proposed to assess overall system voltage stability of a multi-bus power system at a particular operating point using the concept of two bus network equivalent. A universal direct voltage stability index has also been explored to assess local (DVSI) as well as overall system voltage stability (DSVSI). An index called system transmission quality factor (STQF) has been developed to assess the power transmission quality of the overall system in the context of voltage stability. Two FACTS controllers, TCSC and STATCOM have also been incorporated in the present study to observe their effectiveness to ensure voltage stabilty. STATCOM has been found to be superior in order to improve voltage stability of power system as compared to TCSC. The developed concept has been validated using practical India Easten Grid (WBSEB system) and it has a high potential of on-line application.