It shall be noted that only in the first two operating modes that is, 1 & 2 the
measurement function calculates exact three-phase power. 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
(Equation 153)
Im( )
=
Q
S
EQUATION1404 V1 EN
(Equation 154)
2
2
=
=
+
S
S
P
Q
EQUATION1405 V1 EN
(Equation 155)
cos
P
PF
S
j
=
=
EQUATION1406 V1 EN
(Equation 156)
Additionally to the power factor value the two binary output signals from the function
are provided which indicates the angular relationship between current and voltage
phasors. Binary output signal ILAG is set to one when current phasor is lagging
behind voltage phasor. Binary output signal ILEAD is set to one 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
Calibration of analog inputs
Measured currents and voltages used in the CVMMXN function can be calibrated to
get class 0.5 measuring accuracy. This is achieved by amplitude and angle
compensation at 5, 30 and 100% of rated current and voltage. The compensation
below 5% and above 100% is constant and linear in between, see example in
figure
.
Section 16
1MRK502052-UEN B
Monitoring
884
Technical manual
Summary of Contents for Relion REG670
Page 1: ...Relion 670 series Generator protection REG670 2 0 IEC Technical manual ...
Page 2: ......
Page 44: ...38 ...
Page 58: ...52 ...
Page 80: ...74 ...
Page 106: ...100 ...
Page 482: ...476 ...
Page 548: ...542 ...
Page 570: ...564 ...
Page 600: ...594 ...
Page 608: ...602 ...
Page 630: ...624 ...
Page 862: ...856 ...
Page 1094: ...1088 ...
Page 1226: ...1220 ...
Page 1250: ...1244 ...
Page 1297: ...1291 ...