Abstract
<bold>Abstract<bold>
Synchrophasors, defined as synchronized phasors, provide a real-time measurement of electrical quantities from across the power system. Applications include wide-area control, system model validation, determining stability margins, maximizing stable system loading,
islanding detection, system-wide disturbance recording, and visualization of dynamic system response.
This research utilized synchrophasor technology, which takes measurements at both ends of the line to validate transmission line distance relay settings. Methods were developed for the calculation of transmission line parameters, specifically the positive-sequence and zerosequence impedance of the line for both transposed and untransposed transmission lines. In the case of parallel lines, in addition to the positive- and zero-sequence impedance of the line, the zero-sequence mutual coupling was derived. For the case of transposed lines, a comparison between the Pi equivalent circuit and distributed parameter lines showed no significant difference between the two methods. PSCAD<sup>TM</sup>/EMTDC<sup>TM</sup> simulations were used to validate and verify the performance of the proposed method for the calculation of the transmission line parameters. Also, field data from Entergy phasor measurement units (PMUs) on a transmission line was presented. The calculation from the field measured data was calculated with actual relay settings and a method was proposed for validating the relay settings.
A Real Time Digital Simulator (RTDS®), GPS satellite-synchronized clock, PMUs, phasor data concentrators (PDCs), communications equipment, and visualization software were used to set up a network and simulate various cases to verify the performance and further validate
the results.