Calculation of Active Power Transfer Capability using Repeated Power Flow Program

  • Ham, Jung-Pil (Department of Electrical Eng. Hong-Ik University) ;
  • Kim, Jung-Hoon (Department of Electrical Eng. Hong-Ik University) ;
  • Lee, Byung-Ha (Department of Electrical Eng. In-Cheon University) ;
  • Won, Jong-Ryul (Department of Electrical Eng. An-Yang University)
  • Published : 2002.03.01


The power transfer capability is determined by the thermal, dynamic stability and voltage limits of the generation and transmission systems. The voltage stability depends on the reactive power limit and it affects the power transfer capability to a great extent. Then, in most load flow analysis, the reactive power limit is assumed as fixed, relatively different from the actual case. This paper proposes a method for determining the power transfer capability from a static voltage stability point of view using the IPLAN which is a high level language used with PSS/E program. The f-V curve for determining the power transfer capability is determined using Repeated Power Flow method. It Is assumed that the loads are constant and the generation powers change according to the merit order. The maximum reactive power limits are considered as varying similarly with the actual case and the effects of the varied maximum reactive power limits to the maximum power transfer capability are analyzed using a 5-bus power system and a 19-bus practical power system.


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