A fundamental study on damping control design using PMU signals from dominant inter-area oscillation paths

This article presents a fundamental study on feedback control using different types of signals available from a dominant inter-area oscillation path; the passageway containing the highest content of the inter-area oscillations. Results from the previous studies verify the persistence and robustness of dominant path signals and suggest that using such signals, effective damping control may be achieved. To corroborate the implication, signals available from phasor measurement units (PMU) e.g. voltage phasors (magnitude and angle) from the dominant path are used as feedback inputs for a power system stabilizer (PSS) control design for damping enhancement. The corresponding performance are compared with those using generator speed, which is a commonly used signal though not available from PMUs, as inputs. Contrary to expectations found in common practice, that of speed being the one of the most effective signal for damping control, it is demonstrated here that their corresponding damping performance is inferior to those using voltage phasors as feedback inputs. A conceptualized two-area system is used to analyze damping performance throughout this study.