Power System Stability Improvement by TCSC Controller Employing Invasive Weed Optimization (IWO) Algorithm Approach

Abstract

Due to the demands of the modern industries and households, the reliable and economic efficient utilization of electric power became a major challenge for the scientists, engineers and researchers. To fulfill those demands, it needs to interconnect large number of generators/turbines and transmit power over a very long transmission lines to the remote areas with heavy loadings, causing unstable system due to small frequency oscillations remaining and growing in the system. Traditionally Power System Stabilizers (PSS) were used to improve the power system stability. Due to reasons PSS failed, Thyristor Controlled Series Compensator (TCSC), which is a member of Flexible AC Transmission System (FACTS) family, used to improve stability instead. In this study, the non-linear model of TCSC controller is used to improve the power system stability. The behaviors of generator parameters such as rotor angle, rotor speed, internal voltage behind Xd‟ and equivalent excitation voltage are tested for the deviations in the oscillation and damping response. Invasive Weed Optimization (IWO) algorithm approach is used to optimize the TCSC controller parameters for each of three different loadings. IWO algorithm searches to find out the finest suitable set of parameters for the TCSC controller parameters, the stability is much effectively improved. To prove the effectiveness of the work, the system is tested with three different loading conditions. The fast acting of the controller, in case of disturbances, is one of the major aims that this work contributed. The cost function of the IWO shows how much this algorithm is efficient for fast optimization of the parameters.