ABB RELION RET670 - Setting Guidelines

protection (reference angle set to 0) to trip if the active power from the generator is less
than about 2%. One should set the overpower protection (reference angle set to 180) to
trip if the power flow from the network to the generator is higher than 1%.
Underpower protection
Overpower protection
Q Q
P P
Operating point
without
turbine torque
Margin Margin
Operate
Line
Operate
Line
Operating point
without
turbine torque
IEC09000019-2-en.vsd
IEC09000019 V2 EN-US
Figure 284: Reverse power protection with underpower or overpower protection
9.12.3 Setting guidelines
SEMOD172134-4 v7
GlobalBaseSel: Selects the global base value group used by the function to define
IBase, VBase and SBase as applicable.
Operation: With the parameter Operation the function can be set Enabled/Disabled.
Mode: The voltage and current used for the power measurement. The setting
possibilities are shown in table
44.
Table 44: Complex power calculation
Set value
Mode Formula used for complex power calculation
A, B, C
* * *
A A B B C C
S V I V I V I= × + × + ×
EQUATION2055-ANSI V1 EN-US (Equation 453)
Arone
* *
AB A BC C
S V I V I= × - ×
EQUATION2056-ANSI V1 EN-US (Equation 454)
PosSeq
*
3
PosSeq PosSeq
S V I= × ×
EQUATION2057-ANSI V1 EN-US (Equation 455)
AB
* *
( )
AB A B
S V I I= × -
EQUATION2058-ANSI V1 EN-US (Equation 456)
Table continues on next page
1MRK 504 163-UUS A Section 9
Current protection
Transformer protection RET670 2.2 ANSI 581
Application manual