Synchronized phasor measurements of a power system event in Eastern Denmark

Two sets of synchronized phasor measurements 200 km apart have been performed during a planned outage of a double 400-kV tie-line between Eastern Denmark and Southern Sweden. The interconnection between Southern Sweden and Eastern Denmark comprises of a double 400-kV line and a double 132-kV line. The outage of the 400-kV tie-line weakened the Eastern Danish power system and excited power oscillations in the interconnected power systems. During this event prototype phasor measurements units (PMU) gave the opportunity of real-time monitoring of positive sequence voltage and current phasors using satellite-based Global Positioning System (GPS). Comparisons between real-time recordings and results from dynamic simulations with PSS/E are presented. The main features from the simulation analysis are successfully verified by means of the corresponding synchronized phasor measurements.