METREL power master MI 2892, Инструкция по эксплуатации

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MI 2892 Power Master Theory and internal operation
159
Total nonactive power (arithmetic):
2 2
fundtot fundtot fundtot
P Sa Qa
 
[var],
(53)
Total power factor (arithmetic):
fundtot
fundtot
tot
Sa
P
DPFa

.
(54)
All fundamental power measurements are calculated from fundamental voltages and currents obtained
from harmonic analysis (see section 5.1.8 for details).
5.1.7 Energy
Standard compliance: IEC 62053-21 Class 1S, IEC 62053-23 Class 2
Energy measurement is divided in two sections: ACTIVE energy based on active power measurement
and REACTIVE energy, based on fundamental reactive power measurement. Each of them has two
energy counters for consumed and generated energy.
Calculations are shown below:
Active energy:
Consumed:


 

m
i
p p
i T i P Ep
1
) ( ) (
[kWh], p: 1,2,3, tot
Generated:


 

m
i
p p
i T i P Ep
1
) ( ) (
[kWh], p: 1,2,3, tot
(55)
Reactive energy:
Consumed:
 
 
 

 
m
i
pCap
m
i
Iind p
i T i Q i T i Q Eq
1 1
) ( ) ( ) ( ) ( [kvarh], p: 1,2,3, tot
Generated:
 
 
 

 
m
i
pInd
m
i
pCap p
i T i Q i T i Q Eq
1 1
) ( ) ( ) ( ) ( [kvarh], p: 1,2,3, tot
(56)
0
0
90
0
180
0
270
0
Ep-
Ep-
Ep+
Ep+
0
0
90
0
180
0
270
0
Eq+
Eq+
Eq- Eq-
L
e
a
d
L
a
g
Active Energy
Fundamental Reactive Energy
L
e
a
d
L
a
g
Figure 5.6: Energy counters and quadrant relationship