ABB Relion SMU615 Technical Manual page 183

1MRS758407 B
SMU615
Technical Manual
Function
Phase sequence current
measurement (CSMSQI)
Phase sequence voltage
measurement (VSMSQI)
Three-phase power and energy
measurement (PEMMXU)
1) The value provided is for 50 Hz network. The value for 60 Hz network is 90/36 (=54 Hz)
In the three-phase power and energy measurement function
PEMMXU, the deadband supervision is done separately for apparent
power S, with the preset value of fixed 10 percent of the Sn, and the
power factor PF, with the preset values fixed at 0.10. . All the power
measurement-related values P, Q, S and PF are reported
simultaneously when either one of the S or PF values exceeds the
preset limit.
Power and energy calculation
The three-phase power is calculated from the phase-to-earth voltages and phase-to-
earth currents. The power measurement function is capable of calculating a complex
power based on the fundamental frequency component phasors (DFT).
* *
S = (U I U I
⋅ + ⋅ +
A B
A B
GUID-8BF2FBFE-B33B-4B49-86AA-C1B326BBBAC1 V1 EN
Once the complex apparent power is calculated, P, Q, S and PF are calculated with the
equations:
P = Re( ) S
GUID-92B45FA5-0B6B-47DC-9ADB-69E7EB30D53A V3 EN
Q = Im( ) S
GUID-CA5C1D5D-3AD9-468C-86A1-835525F8BE27 V2 EN
2 2
S S P Q
= = +
GUID-B3999831-E376-4DAF-BF36-BA6F761230A9 V2 EN
P
Cos
ϕ =
S
GUID-D729F661-94F9-48B1-8FA0-06E84A6F014C V2 EN
Depending on the unit multiplier selected with Power unit Mult, the calculated power
values are presented in units of kVA/kW/kVAr or in units of MVA/MW/MVAr.
Settings
Ps Seq A deadband , Ng Seq A
deadband , Zro A deadband
Ps Seq V deadband , Ng Seq V
deadband , Zro V deadband
-
*
U I )
⋅
C
C
Section 7
Measurement functions
Maximum/minimum (=range)
40/0 (=40xIn)
4/0 (=4xUn)
(Equation 10)
(Equation 11)
(Equation 12)
(Equation 13)
(Equation 9)
177