OICC Press Majlesi Journal of Electrical Engineering 2345-3796 3 3 2024 02 28 The Optimal Locating of Power Controller in Transmission Line With Consideration of Optimal Power Flow 10.1234/mjee.v3i3.116 EN Mostafa Eidiani Energy Security and Sustainable Energy Institute, Mashhad, Iran. 0000-0001-7736-6674 Journal Article 2024 02 28 In this paper two power elements for power controller in transmission line are presented: Variable Frequency Transformer (VFT) and Rotary Power Flow Controller (RPFC). In addition, here a new Optimal Power Flow (OPF) with these elements is presented. In this paper, it has been made use of the Impedance and Admittance nonsymmetrical matrix and the matrix of loss or coefficient B are calculated in a new method. It has also been indicated that the system is not optimized if optimal power flow is not considered in locating and power of flow controller in line. The proposed method was applied to a 26-bus and 6-generator system and the results were satisfactory.