Voltage Stability Evaluation of The Khouzestan Power System in Iran Using CPF Method and Modal Analysis

Voltage stability is an important factor that needs to be taken into consideration during the planning and operation of power systems in order to avoid voltage collapse and subsequently partial or full system blackout. The study of the voltage collapse phenomenon can provide a way to prevent this event from happening. There have been many methods developed to study the criteria of voltage collapse phenomenon but static analysis probably provide the best way to study this phenomenon. This paper presents Continuation Power Flow (CPF) method to assess voltage stability of the Khouzestan power system in Iran for both normal operation and for contingencies. In rest of this work Modal analysis is used to complete the voltage stability evaluation. The voltage stability of the system has been analyzed during the peak load condition of the summer 2007. The calculation identifies the weakest bus where remedial action may be needed for voltage support.