A Simple Scheme for Wide Area Detection of Impending Voltage Instability

This paper proposes a synchrophasor-assisted simple scheme suitable for on-line anticipation of the impending long-term voltage instability in the power system. The proposed scheme utilizes the bus voltage magnitude and the consecutive bus voltage deviations in the system. These two criteria are combined by means of their weighted sum, to define a Synchrophasor Based Voltage Instability Monitoring Index (SVIMI). A new algorithm is also developed for updation of the criteria weights. The performance of the proposed scheme is demonstrated on New England (NE) 39-bus system and Northern Regional Power Grid (NRPG) 246-bus Indian system. The test results are also compared with two existing voltage stability monitoring schemes to demonstrate the effectiveness of the proposed method.