ABB RELION RET670, Applications Manual

Page: 319 / 1016

8.6.1 Identification
GUID-39299546-12A2-4D9D-86D0-A33F423944E4 v2
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Additional distance protection
directional function for earth faults
ZDARDIR
S00346 V1 EN-US
-
8.6.2 Application
SEMOD154885-5 v9
The phase-to-ground impedance elements can be supervised by a phase unselective
directional function based on symmetrical components (option).
8.6.3 Setting guidelines
SEMOD154897-5 v6
AngleRCA and AngleOp : these settings define the operation characteristic. Setting
AngleRCA is used to turn the directional characteristic, if the expected fault current
angle does not coincide with the polarizing quantity to produce the maximum torque.
The angle is positive, if operating quantity lags the polarizing quantity and negative if
it leads the polarizing quantity. The setting
AngleOp (max. 180 degrees) defines the
wideness of the operating sector. The sector is mirror-symmetric along the MTA
(Maximum Torque Axis).
Directional elements for ground-faults must operate at fault current values below the
magnitude of load currents. As phase quantities are adversely affected by load, the use
of sequence quantities are preferred as polarizing quantities for the ground directional
elements. Optionally six modes are available:
• Zero-sequence voltage polarized (-V
0
)
• Negative-sequence voltage polarized (-V2)
• Zero-sequence current (I
0
)
• Dual polarization (-V
0
/I
0
)
• Zero-sequence voltage with zero-sequence current compensation (-V0Comp)
• Negative-sequence voltage with negative-sequence current compensation (-
V2Comp)
The zero-sequence voltage polarized ground directional unit compares the phase angles
of zero sequence current I
0
with zero sequence voltage -V
0
at the location of the
protection.
1MRK 504 163-UUS A
Section 8
Impedance protection
Transformer protection RET670 2.2 ANSI 313
Application manual