ABB REG670 - Check the Overcurrent Block Function; Single Transformer

condition, the voltage regulation function is not blocked and a lower command
should be issued from the IED.
13.10.3.6 Check the overcurrent block function
SEMOD175185-605 v5
1. Confirm the setting for Iblock in the local HMI under Main menu/Settings/
Setting group N/Control/TransformerVoltageControl(ATCC,91)/
TR1ATCC:x/TR8ATCC:x/TCCtrl/Iblock
2. Confirm the voltage control function response to an applied current above Iblock,
by reviewing the settings in the local HMI under Main menu/Settings/General
settings/Control/TransformerVoltageControl(ATCC,91)/TR1ATCC:x/
TR8ATCC:x/OVPartBk. This condition may cause an alarm or total block of
the voltage control function to be displayed on the local HMI.
3. Inject a current higher than the Iblock setting and confirm the alarm or blocking
condition is present on the local HMI. If an automatic or total blocking condition
occurs, change the applied secondary voltage and confirm that no tap change
commands are issued from the associated binary outputs. This situation can also
be confirmed through reviewing the disturbance and service reports on the local
HMI.
13.10.3.7 Single transformer
SEMOD175185-669 v2
Load drop compensation
SEMOD175185-672 v5
1. Confirm that OperationLDC is set to Enabled.
2. Confirm settings for Rline and Xline.
3. Calculate the expected load voltage V
L
(displayed as a measured value on the
local HMI) based on secondary injection of transformer secondary voltage (VB =
VSet) and rated load current (I
L
= I1Base), in accordance with equation 111.
V
L
= VB - (Rline + jXline) . I
L
EQUATION2081-ANSI V2 EN-US
(Equation 111)
where:
V
L
, I
L
= Re(I
L
) + jlm(I
L
) are complex phase quantities
When all secondary phase-to-ground voltages are available, use the positive-
sequence components of voltage and current. By separation of real and imaginary
parts:
1MRK 502 073-UUS A Section 13
Testing functionality by secondary injection
Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062 263
Commissioning manual