#facts controller

Flexible ac transmission systems (FACTSs) and voltage-source converters, with smart dynamic controllers, are emerging as a stabilization and power filtering equipment to improve the power quality. Also, distributed FACTSs play an important role in improving the power factor, energy utilization, enhancing the power quality, and ensuring efficient energy utilization and energy management in grids. This paper presents a literature survey of FACTS technology tools and applications for power quality and efficient utilization of electric system. There are some drawbacks of FACTS devices. These drawbacks can be fulfilled by using new compound, scalable, light weighted and cost effective devices that are distributed-FACTS (D-FACTS). D-FACTS controllers are distributed version of conventional lumped FACTS controllers and their cost is low due to lower ratings of component and reliability also increases due to redundancy of devices. The Enhanced Power Flow Controller (EPFC) is a D-FACTS controller which is distributed version of thyristor controlled series controller. DPFC controllers are used in series at small distance gap at every 5-10 km distance with transmission line to control the power flow. This paper discusses extensive review of the DPFC controller and its application in modern power system era.