Parallel Voltage Regulation - ABB RET670 Commissioning Manual

Section 11
Testing functionality by secondary injection
11.10.3.8
242
= -
ul im ub im , , xline il re rline il im
EQUATION2084 V1 EN-US
where:
ub is the complex value of the busbar voltage
il is the complex value of the line current (secondary side)
rline is the value of the line resistance
xline is the value of the line reactance
For comparison with the set-point value, the modulus of U
equation 110.
2
¦ U ¦ = (ul , re) + (ul , im)
L
EQUATION2086 V2 EN-US
4. Inject voltage for U
5. Inject current equal to rated current I2Base.
6. Confirm on the local HMI that service values for bus voltage and load current
are equal to injected quantities.
7. Confirm that the calculated value for load voltage, displayed on the local
HMI, is equal to that derived through hand calculations.
8. When setting OperationLDC set to On, the voltage regulation algorithm uses
the calculated value for load voltage as the regulating quantity to compare
against USet and the voltage deadband limits UDeadband and
UDeadbandInner.
9. While injecting rated current I2Base into the IED, inject a quantity for U
that is slightly higher then USet + |(Rline+jXLine) · I
the regulating voltage U
command should be issued from the IED.
10. Reduce the injected voltage for U
and confirm that the calculated value for load voltage is below USet and a tap
change command is issued from the IED.

Parallel voltage regulation

Master follower voltage regulation
1. For the transformers connected in the parallel group, confirm that
OperationPAR is set to MF.
2. For parallel operation, it is also recommended to confirm for parallel group
membership, defined by setting TnRXOP in the local HMI under Main
menu/Settings/Setting group N/Control/
TransformerVoltageControl(ATCC,90)/TR8ATCC:x/ParCtrl
× - ×
, ,
2
equal to setting USet.
B
is higher than USet, and hence no tap change
L
slightly below USet + |(Rline+jXLine) · I
B
1MRK 504 165-UEN A
(Equation 109)
are according to
L
(Equation 110)
|. This will ensure that
L
SEMOD175185-714 v2
SEMOD175185-716 v6
Transformer protection RET670 2.2 IEC
Commissioning manual
B
|
L