Wide Area Protection against Voltage Collapse using a Novel Online Composite Index

One of the three aspects of the stability in power systems is voltage stability. Since voltage collapse can be a reason of the global blackout in power networks, the importance of this study is revealed. In this regard, this paper focuses on transient voltage stability problem and to achieve this goal we use wide area measurement system. To transient voltage stability assessment, a novel fast index is used. The index in one of its three parts monitors the produced reactive power in the network. Important events like generator outage, line outage and load increasing are studied in the paper. Simulation results in the DIgSILENT Power Factory software on IEEE 39 buses dynamic system demonstrate the efficiency of proposed approach with respect to other methods.