Mitsubishi Electric 800 Series Hardware Instruction Manual page 85

 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 (refer to
83), harmonics must be calculated by the equation in next subheading.
P0 = Σ (Ki × Pi) [kVA]
Ki: Conversion factor (Refer to
Pi: Rated capacity of harmonic generating equipment
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: actual load factor × operation time ratio during 30 minutes
• Harmonic content: Refer to
 Rated capacities and outgoing harmonic currents of inverter-driven motors
Rated
current (A)
Applicable
motor (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
No. Item
Reactor installation (FR-
1
HAL)
High power factor
2
converter (FR-HC2)
Installation of power factor
3
improving capacitor
Transformer multi-phase
4
operation
5 Passive filter (AC filter)
6 Active filter
84
3. PRECAUTIONS FOR USE OF THE INVERTER
3.2 Power supply harmonics
page 83.)
*1
[kVA]
page 83.
Fundamental
wave current Rated
converted capacity
from 6.6 kV (kVA)
(mA)
7455 87.2
8909 104
10848 127
13091 153
15636 183
21515 252
24424 286
27273 319
30667 359
34606 405
38970 456
43818 512
48727 570
54545 638
61394 718
With the DC reactor equipped on its DC side, the converter unit (FR-CC2) can suppress the outgoing
harmonic current. Install an AC reactor (FR-HAL) on the AC side of the inverter to further suppress
outgoing harmonic currents.
This converter trims the current waveform to be a sine waveform by switching the rectifier circuit
(converter module) with transistors. Doing so suppresses the generated harmonic amount significantly.
Connect it to the DC area of an inverter. Use the high power factor converter (FR-HC2) with the
accessories that come as standard.
When used with a reactor connected in series, the power factor improving correction capacitor can
absorb harmonic currents.
Use two transformers with a phase angle difference of 30° in combinations of
provide an effect corresponding to 12 pulses, reducing low-degree harmonic currents.
A capacitor and a reactor are used together to reduce impedances at specific frequencies. Harmonic
currents 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
equivalent to a difference between that current and a fundamental wave current to suppress the
harmonic current at the detection point. Harmonic currents are expected to be absorbed greatly by using
this technique.
*1 Rated capacity: Determined by the capacity of the applied
motor and found in the following table. 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
2237 969 626
2673 1158 748
3254 1410 911
3927 1702 1100
4691 2033 1313
6455 2797 1807
7327 3175 2052
8182 3545 2291
9200 3987 2576
10382 4499 2907
11691 5066 3274
13146 5696 3681
14618 6335 4093
16364 7091 4582
18418 7981 5157
Description
13th 17th 19th
373 350 239
445 419 285
542 510 347
655 615 419
782 735 500
1076 1011 688
1221 1148 782
1364 1282 873
1533 1441 981
1730 1627 1107
1949 1832 1247
2191 2060 1402
2436 2290 1559
2727 2564 1746
3070 2886 1965
to Δ and Δ to Δ, to
page
23rd 25th
224 164
267 196
325 239
393 288
469 344
645 473
733 537
818 600
920 675
1038 761
1169 857
1315 964
1462 1072
1636 1200
1842 1351