Voltage stability constrained ATC calculation with contingency analysis in deregulated power systems

Since a couple of decades ago voltage stability assessment has received an increasing attention due to complexity of the power system. With the increase in power demand and limited power sources has caused the system to operate at its maximum capacity. It demonstrates line stability index in order to determine voltage stability limits in the power system. Promoting open access in the electricity industry has ultimately forced power systems around the globe to run closer to their operating limits. Many past experiences and recent incidents have once again highlighted the significance of power system security issues, and costs of its negligence can prove to be catastrophic. In this paper the line stability indices and the feasibility limit at different cases of line outages and generator outages are calculated. A case study of a 9-bus system and IEEE 30-bus Systems are presented to demonstrate the proposed technique.