Abstract

Flexible AC Transmission Systems (FACTS) and their controllers are of great interest today. FACTS controllers can offer great opportunities in modern power system, allowing better and safer operation of the grid. Their technical benefits are very well acknowledged, but there are some factors limiting the widespread of this technology: a) lack of a comprehensive consideration of FACTS for multiple operational problems and operational conditions, b) lack of economic assessment of FACTS projects for utilities and transmission entities [1] c) lack of a clear understanding of the options of devices and their configurations [1], and most importantly d) the high degree of uncertainty associated with the transmission system on the time scale that is needed to assess this kind of long-term projects. This paper gives a brief introduction of various FACTS devices and their controllers, main research methods. We mainly provide a survey of FACTS' economic assessment method proposed so far. We conclude that there is a huge literature body of technical benefits associated with FACTS targeting on single operational problems, but limited work on addressing their practical application considerations, and economic evaluation, offering great research opportunities. © 2009 IEEE.