Coordinated Tuning of AVRs and PSSs for Local and Inter-Area Modes of Oscillation in Eastern Regional Grid of India

A wide range of events can cause oscillations in power systems. Most oscillations are dampened by the system, but a few oscillations may remain undamped, causing the system to collapse. As a result, in the history of modern power system operation and control, low frequency oscillations (LFOs) investigation is necessary. This paper explains the small signal stability analysis of eastern regional (ER) grid neglecting the impact of other regional grids of India. The modal analysis is performed to know the LFO modes in ER grid system. The coordinated tuning of automatic voltage regulators (AVRs) and power system stabilizers (PSSs) have been carried out to damp out these LFO modes and provide required stability margin. The modes those are excited during the disturbance having less damping and high amplitude have been studied and discussed. The truncated 102-bus ER grid system of India is considered for this analytical study.