In modern days due to the ever increasing in demand for electric power, the transmission lines are usually required to operate under full load condition and, consequently, there is a higher impact to the power flow in case the large interconnected transmission networks encounter faults due to many factors. Changing loads and atmospheric conditions are unpredictable factors. This paper purposes power flow control between parallel lines by using Thyristor Controlled Series Capacitor (TCSC). It is a series controller from the flexible AC Transmission System (FACTS) family. It consists of back to back Thyristor. By changing the firing angle of this back to back Thyristor it is possible to vary the reactance of the TCSC. In this paper this device is used to regulate the transmission line reactance in order to share power flow if any disturbance occurs during the transfer of electric power. This device can also work continuously by solving the errors in transmission lines. The systematic procedure for modeling and simulation are proposed by using MATLAB/ Simulink. The optimal location of TCSC device is considered for power flow control. The proposed approach is carried out on two area test system.