ABB RELION 650 Series Applications Manual page 94

Section 6
Differential protection
RED
670
IEC04000209 V1 EN-US
Figure 44: One two–winding transformer in the protected zone (example showing 670
Another alternative is with one three-winding transformer in the protected zone, shown in
figure 45. Observe that in this case, the three-winding power transformer is seen by the
differential protection as two separate power transformers, A and B, which have one common
winding on the HV side.
A
RED
670
IEC15000451 V1 EN-US
Figure 45: One three–winding transformer in the protected zone (example showing 670
TraAOnInpCh
This parameter is used to indicate that a power transformer is included in the protection zone
at current terminal X. This can be either a two-winding transformer or the first secondary
winding of a three-winding transformer. The current transformer feeding the IED is located at
the low voltage side of the transformer. The parameter is set within the range 0...3, where 0
(zero) is used if no transformer A is included in the protection zone. This is one of the few
settings that can be set differently for each separate master IED.
The setting specifies the current input on the differential current function block where the
input current must be recalculated, that is, referred to the high voltage side, which is the
reference side of the differential protection. The measured current, fed to the input channel
determined by the setting
RatVoltW1TraA and shifted counterclockwise by the angle, determined by the product
ClockNumTransA × 30 degrees.
RatVoltW1TraA
The rated voltage (kV) of the primary side (line side = high voltage side) of the power
transformer A.
RatVoltW2TraA
The rated voltage (kV) of the secondary side (non-line side = low voltage side) of the power
transformer A.
88
RED
670
device)
device)
TraAOnInpCh , will be recalculated to I · RatVoltW2TraA /
Protected zone
Protected zone
T
T
1MRK 505 363-UEN A
RED
670
en04000209.vsd
B
RED
670
IEC15000451-1-en.vsd
Application manual
M12541-239 v5
M12541-279 v3
M12541-282 v3