ABB RELION RET670 Applications Manual page 15

Transformer protection RET670 2.2 ANSI
Application manual
Identification.................................................................................... 396
Application....................................................................................... 396
System grounding.......................................................................397
Fault infeed from remote end..................................................... 399
Load encroachment....................................................................400
Short line application.................................................................. 401
Long transmission line application..............................................402
Parallel line application with mutual coupling............................. 403
Tapped line application...............................................................410
Series compensation in power systems.......................................... 413
Steady state voltage regulation and increase of voltage
collapse limit............................................................................... 413
Increase in power transfer.......................................................... 414
Voltage and current inversion.....................................................415
Impact of series compensation on protective IED of
adjacent lines..............................................................................424
Distance protection.....................................................................425
Underreaching and overreaching schemes................................426
Setting guidelines............................................................................ 433
General.......................................................................................433
Setting of zone 1.........................................................................434
Setting of overreaching zone......................................................434
Setting of reverse zone...............................................................435
Series compensated and adjacent lines.....................................435
Setting of zones for parallel line application............................... 440
Setting of reach in resistive direction..........................................442
Load impedance limitation, without load encroachment
function....................................................................................... 443
Zone reach setting higher than minimum load impedance.........444
Parameter setting guidelines...................................................... 445
ZMMMXU settings...................................................................... 448
Power swing detection ZMRPSB (68).................................................. 448
Identification.................................................................................... 448
Application....................................................................................... 449
General.......................................................................................449
Basic characteristics...................................................................449
Setting guidelines............................................................................ 450
Power swing logic PSLPSCH .............................................................. 458
Identification.................................................................................... 458
Application....................................................................................... 458
Table of contents
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