Transient stability improvement in multi-machine system using power system stabilizer (pss) and static var compensator (svc)

Modern power systems are equipped with auxiliary equipments to consider power system stability, especially transient stability and small disturbance. Transient stability plays more effect role in stability of power system, during fault and huge disturbance. In this thesis, we offers comparative between power system stabilizer (PSS) and static Var compensator (SVC) used to improve damping oscillation and transient stability. Power system stabilizer is one of the traditionally devices and common controls applied to damp out the low frequency oscillations. The efficiency of a power system stabilizer PSS connected to the exciter and/or governor unit in damping electromechanical oscillations of isolated synchronous generator is verified. Also, the static Var compensator SVC device is a member of shunt flexible AC transmission system (FACTS) family, it is the recent development of power electronics. SVC makes contribution to improve the stability of the power system by controlling the amount of reactive power injected into or absorbed from the power system. The designed model has been tested for multi machine contain of 4 synchronous machine 6 bus with difference load simulated by software program, and took several cases. All simulation results show that SVC is superior to PSS in improving transient stability and damping oscillation.