Abstract—The unified power flow controller (UPFC) is one of the FACTS devices vastly applied in power systems. This paper presents the modeling of a new structure of UPFC consists of two shunt voltage-source converters and a series capacitor. Through the presented modeling, the transient and steady states responses of UPFC are well investigated. The results of the investigation are presented for the transient and steady states by simulating proposed system in MATLAB changing each system parameter.

Index Terms—FACTS devices, steady state modeling, transient state modeling, UPFC.

Farzad Mohamamdzadeh Shahir is with Faculty of Electrical and Computer Engineering, University of Tabriz, Tabriz, Iran (e-mail: fmohammadzadeh@iau-ahar.ac.ir, f.m.shahir@gmail.com).
Ebrahim Babaei is with Faculty of Electrical and Computer Engineering, University of Tabriz, Tabriz, Iran (e-mail: ebabaei@ tabrizu.ac.ir).