In this work, different types of Flexible Alternating Current Transmission Line controller and their performance have been discussed to use in the transmission line. Improvement of transmission capability has been showed by simulation software such as PSpice, Microsoft Visio, Paint and MATLAB/SIMULINK. Different case studies have also been investigated to verify the performance of proposed inverter and flexible alternating current transmission line controller. The simulation results prove that the controller with the proposed switching scheme functions successfully as the real time voltage and var controller. The performed work also will be able to minimize the reactive power flow in the transmission line. It is observed that, installing the flexible alternating current transmission line controller makes it possible to maintain the unity power factor to ensure maximum usage of transmission capability and improves the dynamic stability.