This study focuses on improving a system’s stability and maximum load capacity and reducing losses in the electrical network using UPFC (unified power flow control) controller’s best location. UPFC is a family of flexible FACTS devices with significant potential for enabling power systems. Voltage stability issues and the ability to transmit power can be significantly reduced using a flexible ac transmission system (FACTS) controller. Compared to other devices controller, UPFC is a FACTS controller that incorporates more particular features and offers both series and shunt compensators. In this study, UPFC is used to increase electrical power dynamic performance through the use of power flow regulation. The existing power transmission line is experiencing issues such as high power losses, voltage fluctuations, and poor system stability. This paper reviews the benefits of using UPFC to improve power transmission line performance. UPFC is able to regulate active and reactive power flows, voltage magnitude and phase angle in real-time, and therefore can enhance the power transmission capacity of the line. Moreover, the UPFC can damp oscillations and improve power system stability. The paper also discusses the control strategies that can be used for UPFC to optimize its performance. Finally, it presents simulation results demonstrating the effectiveness of the UPFC in improving power transmission line performance, including increased power transfer capability and improved stability margins. The MATLAB/SIMULINK environment has been used to conduct all simulations for this work.