Nima Amjady - WEE Member Department of Electrical Engineering Semnan University, Semnan, Iran
Masoud Esmaili - National Dispatching Department Tavanir Company, Tehran, Iran

Voltage security problems have been one of the major concerns for electric utilities as a result of system heavy loading In this paper, continuation method is used for voltage security monitoring of electric power systems. By using continuation method, voltage stability margin of power system at base case and contingency is computed. Also, two systematic methods for determining the most vulnerable buses of power system are presented. These buses are the best candidates for voltage collapse of power system. The proposed methods have been examined on the test system of New Zealand and Iran's power system network. Obtained results confirm the validity of the developed approaches.

Voltage Stability, Continuation Method