ABB Relion 670 Series RES670, Техническое руководство

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Set value: Mode Formula used for complex power calculation
C,A
*
C A CA
*
S V (I I
)
= ×
-
EQUATION2043 V1 EN
(Equation 43)
A
*
A A
S 3 V I
= × ×
EQUATION2044 V1 EN
(Equation 44)
B
*
B B
S 3 V I
= × ×
EQUATION2045 V1 EN
(Equation 45)
C
*
C
C
S 3 V I
= × ×
EQUATION2046 V1 EN
(Equation 46)
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
pickup signal PICKUP1(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 pickup signal is still active. At activation of any of the two stages a common signal
PICKUP 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 value.
The drop-power value of stage1 can be calculated with the
Power1(2) , Hysteresis1(2) :
drop-power1(2) = Power1(2) – Hysteresis1(2)
For small power1 values the hysteresis1 may not be too big, because the drop-power1(2)
would be too small. In such cases, the hysteresis1 greater than (0.5 ·
Power1(2) ) is
corrected to the minimal value.
If the measured power drops under the drop-power1(2) value the function will reset after
a set time
DropDelay1(2) . The reset means that the pickup signal will drop out ant that the
timer of the stage will reset.
Section 8
1MRK 511 365-UUS A
Current protection
264 Phasor measurement unit RES670 2.1 ANSI
Technical manual