T&D World Magazine
SEL-487E Transformer Protection Relay Now Offers Real-Time Control

SEL-487E Transformer Protection Relay Now Offers Real-Time Control

Schweitzer Engineering Laboratories, Inc. (SEL) has announced wide-area-measurement-based control in a transformer relay for the first time. This enhancement to the SEL-487E Transformer Protection Relay allows it to receive IEEE C37.118 synchrophasor messages from up to two phasor measurement units, time-correlate the information, and take control actions based on local and remote messages. Remote angles, currents, and voltages received in the serial synchrophasor message can be combined with local measurements for basic or advanced applications.

"A multirestraint transformer differential relay, such as the SEL-487E, is an ideal platform for synchrophasor-based control," said Roy Moxley, SEL marketing manager for synchrophasors. "Large generators and transmission stations that frequently use this type of relay can now easily apply remote measurements to control tap changers, regulate generator voltage, and notify operators of system conditions."

This advanced SEL-487E Relay communications technology allows customers to:

  • Trip or start generators based on system load angles.
  • Control tap position based on combined values.
  • Send alarms based on changing angles.
  • Apply SELogic control equations to time-correlated remote measurements.
  • Detect system separation to initiate islanding control.
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