ABB RED650, Техническое руководство

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Set value for
parameter
“Mode”
Formula used for complex, three-
phase power calculation
Formula used for voltage and
current magnitude calculation
Comment
8 L2
*
2 2
3
= × ×
L L
S U I
EQUATION1399 V1 EN-US
(Equation 69)
2
2
3
= ×
=
L
L
U U
I I
EQUATION1400 V1 EN-US
(Equation 70)
Used when
only U
L2
phase-to-
earth voltage
is available
9 L3
*
3 3
3
= × ×
L L
S U I
EQUATION1401 V1 EN-US
(Equation 71)
3
3
3
= ×
=
L
L
U U
I I
EQUATION1402 V1 EN-US
(Equation 72)
Used when
only U
L3
phase-to-
earth voltage
is available
* means complex conjugated value
It shall be noted that only in the first two operating modes that is, 1 & 2 the
measurement function calculates the three-phase power accurately. In other
operating modes that is, from 3 to 9 it calculates the three-phase power under
assumption that the power system is fully symmetrical. Once the complex apparent
power is calculated then the P, Q, S, & PF are calculated in accordance with the
following formulas:
Re( )
=
P S
EQUATION1403 V1 EN-US
(Equation 73)
Im( )
=
Q S
EQUATION1404 V1 EN-US
(Equation 74)
2 2 = = +
S S P Q
EQUATION1405 V1 EN-US
(Equation 75)
cos
P
PF
S
j
= =
EQUATION1406 V1 EN-US
(Equation 76)
Additionally to the power factor value, the two binary output signals from the
function are provided which indicates the angular relationship between the current
and voltage phasors. Binary output signal ILAG is set TRUE when current phasor
is lagging behind voltage phasor. Binary output signal ILEAD is set TRUE when
current phasor is leading the voltage phasor.
Each analogue output has a corresponding supervision level output (X_RANGE).
The output signal is an integer in the interval 0-4, see section
"Measurement
supervision" .
Section 15
1MRK 505 394-UEN A
Monitoring
526 Line differential protection RED650 2.2 IEC
Technical manual