Research Article
K. Venkata Ramana Reddy, M.
Abstract
In this paper an IEEE standard test system has been considered and Load flows were computed by using Newton- Raphson method with the help of MATLAB and a weak bus is identified. The bus that is with a low voltage magnitude is incorporated with FACTS devices namely TCSC and SVC in order to improve the voltage under normal conditions. Then the reactive power at a particular bus is increased until it reaches to the instability point and the voltage stability condition is evaluated by using an L-index method. The values which approach unity imply that it reaches to instability, and corresponding bus can be treated as weak bus i.e. with a highest value of L-index, and is incorporated with FACTS devices to enhance the voltage stability under post-fault steady state condition also.