DAMPING OF LOW FREQUENCY OSCILLATIONS USING SYNCHROPHASOR MEASUREMENTS FROM WIDE AREA MEASUREMENT SYSTEM

Abstract

Increased progress of power systems has led to a structure of close generator groups connected to other groups by weak transmission lines. This has been known to cause oscillations were these groups oscillate against each other in an inter area fashion. This implies that power oscillates between areas and thus diminishes the transmission capability of the interconnected system. Growing oscillations eventually lead to loss of synchronism in a power system which can cause damage. In order to prevent damage under such circumstances, generators would have be disconnected from the system. This can cause disturbances or even worse, blackouts. Damping of oscillations thus plays a significant role in power system security by securing and increasing supply and transmission capability of the system. Some power system blackout incidents due to low frequency oscillation are given in the paper. The actual questions of the study of low-frequency oscillations of power in the interconnected power system (IPS) of Ukraine in terms of introduction of modern Wide Area Measuring System (WAMS) are considered. This paper describes the damping controller design for power system oscillations in interconnected power systems by means of using recordings of a WAMS. The global signal from Phasor Measurement Unit is an additional global signal for damping interarea modes. The choice of location, input signals and tuning of power oscillation damping controller based on residue method. The effectiveness of the proposed power oscillation damping controller are tested on a Kundur’s two - area system in DigSilent Power Factory.