Modelling and analysis of facts devices for stability improvement in power system using MATLAB software

The concept of FACTS (Flexible Alternating Current Transmission System) refers to a family of power electronics-based devices able to enhance AC system controllability and stability and to increase power transfer capability. FACTS devices, thanks to their speed and flexibility, are able to provide the transmission system with several advantages such as: transmission capacity enhancement, power flow control, transient stability improvement, power oscillation damping and voltage stability. This project investigates modelling and analysis of static Var Compensator (SVC), Static Synchronous Compensator (STATCOM) and Unified Power Flow Controller (UPFC) performance for stability improvement in power system. The ability of these FACTS devices for power flow control at normal condition are examined. In addition, the capability for damping electromechanical oscillations at fault condition in a power system are studied by these devices. This is achieved by modelling three phase test system 220KV in long transmission line. Furthermore, the UPFC device has tested in Kundur’s Four-Machine Test System at fault condition. The MATLAB/Simulink software is used to compare between different FACTS devices performance. The performance of SVC, STATCOM and UPFC is compared from each other. In comparative result UPFC is given the better result than the others. The simulation results in both of the test systems demonstrate the effectiveness and robustness of the proposed SVC, STATCOM and UPFC on stability improvement of the power system.