ABB REG670 Commissioning Manual page 273

1MRK 502 073-UUS A
Generator protection REG670 2.2 ANSI and Injection equipment REX060, REX061, REX062
Commissioning manual
7. Confirm that a circulating current is measured on the local HMI that is equal in
magnitude to 5% of I2Base, with polarity as discussed in step 6.
8. Confirm the settings for Ci (Compensation Factor) and Xi (Transformer Short
Circuit Impedance). Using these setting values and the measured quantity of
circulating current from the local HMI (Icc_i), calculate the value for circulating
current voltage adjustment Vci.
= × ×
Vdi Ci Icc i Xi _
EQUATION2089-ANSI V1 EN-US
The voltage regulation algorithm then increases (for transformer T2) or decreases
(for transformer T1) the measured voltage by Vdi and compares Vi against the
voltage deadband limits V1 and V2 for the purposes of voltage regulation.
= +
Vi VB Vdi
EQUATION2091-ANSI V1 EN-US
9. To cause a tap change, the calculated value for circulating current voltage
adjustment must offset the injected quantity for bus voltage V
outside the voltage deadband created by setting VDeadband. Expressed by
equation 117 and equation 118.
> -
Vdi V 2 VB
(Equation 117)
EQUATION2093-ANSI V1 EN-US
=
VB Vset
(Equation 118)
EQUATION2095-ANSI V1 EN-US
Therfore:
× ×
Ci Icc i Xi V _
EQUATION2097-ANSI V1 EN-US
(
-
V 2
>
Icc i _
EQUATION2099-ANSI V1 EN-US
Testing functionality by secondary injection
(for the purposes of this test procedure)
> -
2 Vset
)
Vset
( )
×
Ci Xi
Section 13
(Equation 115)
(Equation 116)
so that Vi is
B
(Equation 119)
(Equation 120)
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