TY - JOUR T1 - Optimal Placement of FACTs Devices Using Hybrid Line Stability Index AU - Ibrahim, Luay G. AU - AL-Rubayi, Rashid H. JO - Journal of Engineering and Applied Sciences VL - 14 IS - 8 SP - 2739 EP - 2744 PY - 2019 DA - 2001/08/19 SN - 1816-949x DO - jeasci.2019.2739.2744 UR - https://makhillpublications.co/view-article.php?doi=jeasci.2019.2739.2744 KW - Hybrid line stability index KW -FACTS device KW -voltage stability index KW -(Lmn) KW -(FVSI) KW -(HLSI) AB - The many of the power cuts in the electricity system in the last decade and in recent times indicate that much research yet necessarily to be done to address the instability voltage and the ensuing collapse. This study presents a method to find and select the optimum location of FACTs device using the Hybrid Line Stability Index (HLSI) that is appropriate for the prediction voltage collapse in power system networks. Such the HLSI was obtained by deriving expressions basics equivalent line stability index (Lmn) and Fast Voltage Stability Index (FVSI) and mix their through a switch logic based on the voltage angle difference where indicate the nearness voltage collapse. The HLSI has tested on IEEE 9-bus system it gives the same results as the other indicators (Lmn and FVSI). For the base state, IEEE 9-bus system was found to be stable with all the three indicators has approximately equal values <1 for all lines. The contingency state detect that ranks of bus 5 the weakest bus in the system with the lower maximum allowable reactive load of (120 MVar) and the line critical concerning bus 5, the line connecting bus 5-7. The values the three indicators, Lmn, FVSI and HSLI, approximately equal increasing the accuracy of HLSI. ER -