Using D-FACTS in microgrids for power quality improvement: A review

Microgrids have attracted much attention in recent years due to their ability to integrate distributed energy resources, storage devices, and loads as well as to operate in grid-connected mode or in islanded mode. Microgrids are expected to provide high-quality power with high efficiency, reliability, and security. However, the inherent intermittent nature of the renewable sources and switching nature of the power electronic interfaces adversely affect the power quality in the microgrid. This paper presents a review of power quality enhancement techniques commonly used in microgrids. Among these techniques, Distribution Flexible Alternating Current Transmission System (D-FACTS) devices show great promise in strengthening AC transmission systems stability and control; providing speed and flexibility for several applications. An extensive overview of the state-of-the-art D-FACTS devices will be presented. As of today, costs and reliability concerns are the main barriers to the integration of these technologies. Wide deployment of these devices will depend on their ability to overcome their limitations through the maturity of the devices and economies of scale.