Effect of static var compensator upon synchronizing torque coefficient

Abstract As power systems have increased in size and complexity, and as the number of power ties between different systems has increased, the nature of the system stability has changed. A static var compensator (SVC), constructed by fixed capacitor (FC) and thyristor controlled reactor (TCR), is designed and implemented to improve the damping of a synchronous generator, as well as controlling the system voltage. The SVC is placed at the generator bus terminal, with the speed and voltage deviation as the feedback signals. In this paper, a formula has been developed showing the effect of SVC upon synchronizing torque coefficient, such that damping is improved and the system voltage is controlled. A simplified analysis of the effect of SVC on the stability of a machine connected to an infinite bus, as well as 21 bus real system is presented. It is observed that the SVC is capable of increasing damping and controlling the system voltage.

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