Transient Stability Improvement Using UPFC and SVC

With increased power transfer, transient stability is increasingly important for secure operation. Transient stability evaluation of large scale power systems is an extremely intricate and highly non-linear problem. An important function of transient evaluation is to appraise the capability of the power system to withstand serious contingency in time, so that some emergencies or preventive control can be carried out to prevent system breakdown. In practical operations correct assessment of transient stability for given operating states is necessary and valuable for power system operation. Static VAR Compensator is a shunt connected FACTS devices, and plays an important role as a stability aid for dynamic and transient disturbances in power systems. UPFC controller is another FACTS device which can be used to control active and reactive power flows in a transmission line. The damping of power system oscillations after a three phase fault is also analyzed with the analyzation of the effects of SVC and UPFC on transient stability performance of a power system. A general program for transient stability studies to incorporate FACTS devices is developed using modified partitioned solution approach. The modeling of SVC and UPFC for transient stability evaluation is studied and tested on a 10-Generator, 39 Bus, New England Test System.