Concepts of Facts Flexible AC Transmission System

This document contains the preface.

This document contains the contents.

A Flexible Alternating Current Transmission System (FACTS) is a system composed of static equipment used for the AC transmission of electrical energy. It is meant to enhance controllability and increase power transfer capability of the network. It is generally a power electronics-based system technology.

The voltage-control action of the SVC can be explained through a simplified block representation of the SVC and power system, as shown in Fig. 2.1. The power system is modeled as an equivalent voltage source, Vs, behind equivalent system impedance, Xs, as viewed from the SVC terminals.

Series capacitors offer certain major advantages over their shunt counterparts. With series capacitors, the reactive power increases as the square of line current, whereas with shunt capacitors, the reactive power is generated proportional to the square of bus voltage. For achieving the same system benefits as those of series capacitors, shunt capacitors that are three to six times more reactive power rated than series capacitors need to be employed.

The STATCOM (or SSC) is a shunt-connected reactive-power compensation device that is capable of generating and/or absorbing reactive power and in which the output can be varied to control the specific parameters of an electric power system. It is in general a solid-state switching converter capable of generating or absorbing independently controllable real and reactive power at its output terminals when it is fed from an energy source or energy-storage device at its input terminals. Specifically, the STATCOM considered.

Controller interactions can occur in the following combinations:
1. Multiple FACTS controllers of a similar kind.
2. Multiple FACTS controllers of a dissimilar kind.
3. Multiple FACTS controllers and HVDC converter controllers.

This document contains the Index.