A New Algorithm to Detect Power Swing and Improve Operation of Distance Relays Zone 3 by Use Of PMU

Cascaded tripping of transmission lines due to mal-operation of zone 3 distance relays is main reason of blackouts worldwide and the main reason ofthese mal-operations is power swing. This paper presents a new approach to power swing detection by using synchronized phasor measurements data andprevent undesirable zone 3 distance relays tripping during stable power swings. Results are presented based on simulation studies carried out on a 400 kVsystem, using EMT DC/PSCAD. The PMU is simulated in MATLAB.

Keywords:

distance relay zone 3 , phasor measurment unit(PMU) , power swing detection