Application of FACTS Devices for Damping of Low-Frequency Oscillations in Azerbaijan's Power System

Abstract

The structure of Azerbaijan's power system is characterized by its substantial heterogeneity, i.e., unevenly loaded transmission lines in a large number of power flows, limited possibility of wheeling through backbone tie-lines due to the bypass power grid operation. The use of Flexible AC Transmission System (FACTS) devices makes it possible to impart active properties to a passive electrical network and thus provide flexible control over the operation of the power system. FACTS devices increase the transfer capability of the electrical network. It is known that a system of automatic control of damping can be used to augment the stability of power systems. Damping may be achieved using other devices installed with the express purpose of stability augmentation. Disruption of stability of the power system is the result of loss of synchronism of the generator rotor because of insufficient damping torque of low-frequency oscillations (usually 0.1–1.0 Hz) and local oscillations (1–3 Hz). We propose improving the damping of low-frequency oscillations by placing a unified power flow controller in the power system. The efficiency of the application is demonstrated through a case study of a 220 kV – 330 kV – 500 kV network.