ABSTRACT
Flexible AC transmission systems (FACTS) and high-voltage direct current (HVDC) technologies are crucial for interconnecting long offshore cables with the offshore wind farms. FACTS and HVDC also have an important role to play in the integration of large-scale, transmission-connected wind farms and solar fields into a smart transmission grid. FACTS systems can be used in various configurations in order to control load flow and to improve dynamic conditions on the grid: in a parallel connection (SVC, STATCOM); in a series connection; or as a combination in both a parallel and series connection. The synchronous condenser's usefulness in the smart grid is not unlike modern FACTS devices. Voltage-source converter (VSC)-HVDC technology is now emerging as a flexible and economical alternative for future transmission grid expansion. VSC-HVDC is the preferred technology for connecting islanded grids, such as offshore wind farms, to the power system. The STATCOM consists of a VSC operating as an inverter with a capacitor as the DC energy source.
