Placement of various FACTS devices in voltage stability analysis based on critical bus.

The electrical system operation continuously approaches the stability threshold due to the demand growth over time. The continued of demand growth overtime can cause a voltage drop makes system becomes unstable. Placement of flexible alternating current transmission (FACTS) is an alternative to improve load margin of the system also improve the voltage profile of the system. The types of FACTS are unified power flow controller (UPFC), static var compensator (SVC), thyristor-controlled series capacitors (TCSC) and static synchronous series compensator (SSSC) respectively. The authors compare several FACTS on improving the stability of the tested system by improving their voltage profile in IEEE 14 bus test system. Using sensitivity index by performed continuation power flow (CPF) to know the placement of FACTS device is proposed. It is proven that the placement of FACTS in the system can improve system stability and reliability by increasing the voltage profile and loading margin. The placement of the UPFC in critical bus of IEEE 14 Bus system increase the maximum loading parameter by 0.22 p.u. (7.99%) and improve the voltage profile of bus 14 by 0.23 p.u. (34.86%). [ABSTRACT FROM AUTHOR]