Residual Voltage Scaling - ABB RELION REX640 Technical Manual

Section 3
Basic functions
3.17.3.4
190
All three phases must to be connected if the main or backup frequency
source is selected.
Frequency adaptive measurements for residual voltage can be activated with the
setting Frequency adaptivity. Two selections are provided.
Table 127: Frequency adaptivity setting for residual voltage measurement
Setting value
Disable
Enable
UTVTR setting Frequency adaptivity is visible only if system setting
Configuration/System/Frequency adaptivity is set to "Enable".

Residual voltage scaling

Calculated U is scaled to the same level as measured U
0
by the ratio of ULTVTR primary voltage and RESTVTR primary voltage within one
UTVTR instance. The assumption is open-delta U
Typical markings of an open-delta U
sqrt(3) :100V/sqrt(3) :100V/3. In case of a solid earth fault, this transformer gives
100 V output which corresponds to 11.547 kV. If ULTVTR primary voltage is set to
20 kV and RESTVTR primary voltage is set to 11.547 kV when this transformer is
used, URES_CLC and URES_MEAS output equal amplitude.
Slot F (AIM).X1-1;2_VT1
Slot F (AIM).X1-3;4_VT2
Slot F (AIM).X1-5;6_VT3
Slot F (AIM).X1-7;8_VT4
GUID-1ADFA88D-6440-4E47-9B38-DC31E6E87EA0 V1 EN
Figure 73: UTVTR1 configured with both measured and calculated U
The VT connection mode must be "WYE".
Description
Frequency adaptive measurements are disabled
for this UTVTR. Measurements are fixed to
nominal frequency defined with Configuration/
System/Rated frequency.
Frequency adaptive measurements are enabled.
In this case, the estimated network frequency is
defined by another preprocessing block.
measurement type.
0
transformer in a 20 kV network can be: 20kV/
0
UTVTR1
UL1 ALARM
UL2 WARNING
UL3 URES_ALARM
MINCB_OPEN URES_WARNING
URES U3P
URES_CLC
URES_MEAS
URES_CLC_DR
URES_MEAS_DR
U1_DR
U2_DR
U3_DR
NPS_DR
PPS_DR
FREQ_DR
O:11|T:2,5|I:1
1MRS759142 C
. The scaling is determined
0
UTVTR1[1]_U3P
UTVTR1[1]_URES_CLC
UTVTR1[1]_URES_MEAS
0
REX640
Technical Manual