Installation and operation of FACTS devices for enhancing steady-state security

This paper presents principles about installation and operation of flexible ac transmission systems (FACTS) devices to enhance the steady-state security of power system. Three generic types of FACTS devices are introduced and the proper location of each kind of FACTS devices is determined in accordance with the individual purpose of use. It is desirable to install shunt controllers where there is a need for voltage support according to V-Q sensitivity analysis and to install series controllers where line flow control is required to increase system loadability. It is also important to install combined series-shunt controllers such as UPFC in order to get most of their merits, that is, to control both the active and reactive power flow. An algorithm to minimize simultaneously and iteratively both kinds of security indices such as J(P) relating to line flow and J(V) relating to bus voltage is proposed in this paper. For minimization of security indices, each sensitivity vector of both indices is derived analytically. Results from the minimization show that optimal operating points of FACTS devices under various conditions of power system have been achieved. The proposed methodology to install and operate FACTS devices properly is verified on the IEEE 57-bus system where FACTS devices were operated under normal condition and in a line-faulted contingency. (C) 2004 Elsevier B.V. All rights reserved.