ABB Relion REG670, Technical Manual, Page: 438 / 1298

Table 227: Complex power calculation
Set value:
Mode
Formula used for complex power calculation
L1, L2, L3
* * *
1 1 2 2 3 3 L L L L L L
S U I U I U I
= × + × + ×
EQUATION1697 V1 EN
(Equation 88)
Arone
* *
1 2 1 2 3 3 L L L L L L
S U I U I
= × - ×
EQUATION1698 V1 EN
(Equation 89)
PosSeq
*
3
PosSeq PosSeq
S U I
= × ×
EQUATION1699 V1 EN
(Equation 90)
L1L2
* *
1 2 1 2
( )
L L L L
S U I I
= × -
EQUATION1700 V1 EN
(Equation 91)
L2L3
* *
2 3 2 3
( )
L L L L
S U I I
= × -
EQUATION1701 V1 EN
(Equation 92)
L3L1
* *
3 1 3 1
( )
L L L L
S U I I
= × -
EQUATION1702 V1 EN
(Equation 93)
L1
*
1 1
3
L L
S U I
= × ×
EQUATION1703 V1 EN
(Equation 94)
L2
*
2 2
3
L L
S U I
= × ×
EQUATION1704 V1 EN
(Equation 95)
L3
*
3 3
3
L L
S U I
= × ×
EQUATION1705 V1 EN
(Equation 96)
The active and reactive power is available from the function and can be used for
monitoring and fault recording.
The component of the complex power S = P + jQ in the direction Angle1(2) is
calculated. If this angle is 0° the active power component P is calculated. If this angle
is 90° the reactive power component Q is calculated.
The calculated power component is compared to the power pick up setting
Power1(2) . A start signal START1(2) is activated if the calculated power component
is larger than the pick up value. After a set time delay TripDelay1(2) a trip TRIP1(2)
signal is activated if the start signal is still active. At activation of any of the two stages
a common signal START will be activated. At trip from any of the two stages also a
common signal TRIP will be activated.
To avoid instability there is a settable hysteresis in the power function. The absolute
hysteresis of the stage1(2) is
Hysteresis1(2) = abs (Power1(2) – drop-power1(2)). For
generator reverse power protection the power setting is very low, normally down to
0.02 p.u. of rated generator power. The hysteresis should therefore be set to a smaller
Section 8
1MRK502052-UEN B
Current protection
432
Technical manual