Abstract:
Recent development of power electronics introduces the use of FACTS devices in power systems. FACTS devices are capable of controlling the network condition in a very fast manner by reactive power management and this unique feature of FACTS devices can be exploited to improve the transient stability of a system. Transient stability control plays a significant role in ensuring the stable operation of power systems in the event of large disturbances and faults. The improvement of transient stability of a two-area power system, using UPFC (Unified Power Flow Controller) which is an effective FACTS (Flexible AC Transmission System) device capable of controlling the active and reactive power flows in a transmission line by controlling appropriately its series and shunt parameters, also combined with Distributed Generation (DG) connected in the DC link to mitigate power quality disturbances. A collection of measured performance characteristics is presented to illustrate the unique capabilities of UPFC. The performance of UPFC is compared with other FACTS devices such as Static Synchronous Series Compensator (SSSC), Thyristor Controlled Series Capacitor (TCSC), and Static VAR Compensator (SVC) respectively.

Keywords: SVC, STATCOM, SSSC, Transient Stability, UPFC