Implementation of distributed compensation in the transmission lines design (D-FACTS)

The design and construction of transmissions lines has been a well-established practice since the beginning of power systems. However, nowadays it is more difficult to build new ones, due to environmental and economic concerns, even technical issues like variable power supplies, affects the new designs of transmission lines. One way to avoid or delay the building of new lines, is to upgrade the old ones, not only by conventional methods but including new technologies, like including power electronics. The design of the transmission lines is a multidisciplinary work, which requires a detailed analysis of each of its basic parameters. On the other hand, the Flexible AC-Transmission Systems (FACTS), have proved to be a valuable tool in optimizing transmission systems. A variant of this technology is the application of power electronics devices embedded along the transmission lines, instead of large-scale substation at its ends; this technology has been called Distributed Flexible AC-Transmission Systems (D-FACTS). D-FACTS are small devices that are accommodated in the power cables. This article presents the concept of D-FACTS technology and its impact on the electromechanical design of new transmission lines.