Mitsubishi Electric FR-F802-E Instruction Manual page 68

Inverter for fans and pumps
Table of Contents

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• Calculation of equivalent capacity P0 of harmonic generating equipment
"Equivalent capacity" is the capacity of a 6-pulse converter converted from the capacity of consumer's harmonic generating
equipment and is calculated by the following equation: If the sum of equivalent capacities is higher than the limit in (refer to
page
66), harmonics must be calculated with the following procedure:
P0 = ∑ (Ki  Pi) [kVA]
Ki: Conversion coefficient (Refer to
Pi: Rated capacity
of harmonic generating equipment [kVA]

i: Number indicating the conversion circuit type
• Calculation of outgoing harmonic current
Outgoing harmonic current = fundamental wave current (value converted from received power voltage)  operation ratio 
harmonic content
• Operation ratio: Operation ratio = actual load factor  operation time ratio during 30 minutes
• Harmonic content: Found in
• Rated capacities and outgoing harmonic currents of inverter-driven motors
Fundamental
Applicable
wave current
motor
(A)
(kW)
400 V
75
123
90
147
110
179
132
216
160
258
220
355
250
403
280
450
315
506
355
571
400
643
450
723
500
804
560
900
630
1013
• Determining if a countermeasure is required
A countermeasure for harmonics is required if the following condition is satisfied: outgoing harmonic current > maximum
value per 1 kW contract power  contract power.
• Harmonic suppression techniques
Item
The converter unit (FR-CC2) is equipped with the DC reactor on its DC side, and outgoing harmonic current
Reactor installation
can be suppressed. By installing an AC reactor (FR-HAL) on the AC side of the inverter, the outgoing harmonic
(FR-HAL)
current suppression performance can be improved.
This converter trims the current waveform to be a sine waveform by switching the rectifier circuit (converter
high power factor
module) with transistors. Doing so suppresses the generated harmonic amount significantly. Connect it to the
converter
DC area of an inverter. Use the high power factor converter (FR-HC2) with the accessories that come as
(FR-HC2)
standard.
Installation of power
When used with a reactor connected in series, the power factor improving correction capacitor can absorb
factor improving
harmonic currents.
capacitor
Transformer multi-phase
Use two transformers with a phase angle difference of 30° as in
operation
corresponding to 12 pulses, reducing low-degree harmonic currents.
Passive filter
A capacitor and a reactor are used together to reduce impedances at specific frequencies. Harmonic currents
(AC filter)
are expected to be absorbed greatly by using this technique.
This filter detects the current in a circuit generating a harmonic current and generates a harmonic current
Active filter
equivalent to a difference between that current and a fundamental wave current to suppress the harmonic
(Active filter)
current at the detection point. Harmonic currents are expected to be absorbed greatly by using this technique.
page
66)
page
66.
Fundamental
wave current
Rated
converted
capacity
from 6.6 kV
(kVA)
(mA)
7455
87.2
2237
8909
104
2673
10848
127
3254
13091
153
3927
15636
183
4691
21515
252
6455
24424
286
7327
27273
319
8182
30667
359
9200
34606
405
10382
38970
456
11691
43818
512
13146
48727
570
14618
54545
638
16364
61394
718
18418
PRECAUTIONS FOR USE OF THE INVERTER

Rated capacity: Determined by the capacity of the
applied motor and found in Table 5. The rated
capacity used here is used to calculate the generated
harmonic amount and is different from the power
supply capacity required for actual inverter drive.
Outgoing harmonic current converted from 6.6 kV (mA)
(With a DC reactor, 100% operation ratio)
5th
7th
11th
13th
969
626
373
1158
748
445
1410
911
542
1702
1100
655
2033
1313
782
2797
1807
1076
3175
2052
1221
3545
2291
1364
3987
2576
1533
4499
2907
1730
5066
3274
1949
5696
3681
2191
6335
4093
2436
7091
4582
2727
7981
5157
3070
Description
- and - combinations to provide an effect
Power supply harmonics
17th
19th
23rd
25th
350
239
224
164
419
285
267
196
510
347
325
239
615
419
393
288
735
500
469
344
1011
688
645
473
1148
782
733
537
1282
873
818
600
1441
981
920
675
1627
1107
1038
761
1832
1247
1169
857
2060
1402
1315
964
2290
1559
1462
1072
2564
1746
1636
1200
2886
1965
1842
1351
3
67

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