Table of Contents
Advertisement
EMC and leakage currents
Not used
Three-phase bridge
Used (AC side)
Used (DC side)
(Capacitor smoothing)
Used (AC, DC sides)
1) Calculation of equivalent capacity (P0) of harmonic generating equipment
The "equivalent capacity" is the capacity of a 6-pulse converter converted from the capacity of consumer's harmonic
generating equipment and is calculated with the following equation. If the sum of equivalent capacities is higher than the
limit in Table 3, harmonics must be calculated with the following procedure:
P0 = Ki
Pi) [kVA]
Ki: Conversion factor (Refer to Table 2.)
Pi: Rated capacity of harmonic generating equipment[kVA]
i: Number indicating the conversion circuit type
2) 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 Table 4.
Table 5 Rated Capacities and Outgoing Harmonic Currents for Drive Unit Drive
Fundamental
Applicable
Wave Current [A]
Motor (kW)
200V
400V
0.1
0.61
0.30
0.2
0.98
0.49
0.4
1.61
0.81
0.75
2.74
1.37
1.5
5.50
2.75
2.2
7.93
3.96
3) Application of the guideline for specific consumers
If the outgoing harmonic current is higher than the maximum value per 1kW contract power contract power, a harmonic
suppression technique is required.
4) Harmonic suppression techniques
No.
Item
Reactor installation
1
(FR-HAL, FR-HEL)
High power factor converter
2
(FR-HC2)
Installation of power factor
3
improving capacitor
Transformer multi-phase
4
operation
Passive filter
5
(AC filter)
Active filter
6
(Active filter)
42
Table 4 Harmonic Contents (Values at the fundamental current of 100%)
Reactor
5th
65
38
30
28
Fundamental
Wave Current
Capacity
Converted from
6.6kV (mA)
18
30
49
83
167
240
Install an AC reactor (FR-HAL) on the AC side of the drive unit or a DC reactor (FR-HEL) on its DC side
or both to suppress outgoing harmonic currents.
This converter trims the current waveform to be a sine waveform by switching in the rectifier circuit
(converter module) with transistors. Doing so suppresses the generated harmonic amount significantly.
Connect it to the DC area of an drive unit. The high power factor converter (FR-HC2) is used with the
standard accessory.
When used with a series reactor, the power factor improving capacitor has an effect of absorbing
harmonic currents.
Use two transformers with a phase angle difference of 30 as in
effect corresponding to 12 pulses, reducing low-degree harmonic currents.
A capacitor and a reactor are used together to reduce impedances at specific frequencies, producing a
great effect of absorbing harmonic currents.
This filter detects the current of 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 a
harmonic current at a detection point, providing a great effect of absorbing harmonic currents.
7th
11th
13th
41
8.5
14.5
7.4
13
8.4
9.1
7.2
* Rated capacity: Determined by the capacity of the applied motor and
found in Table 5. It should be noted that the rated capacity used here is
used to calculate generated harmonic amount and is different from the
power supply capacity required for actual drive unit drive.
Outgoing Harmonic Current Converted from 6.6kV (mA)
Rated
(No reactor, 100% operation ratio)
(kVA)
5th
7th
0.22
11.7
7.38
0.35
19.5
12.3
0.57
31.85
20.09
4.165
0.97
53.95
34.03
7.055
1.95
108.6
68.47
14.20
2.81
156.0
98.40
20.40
Description
17th
19th
7.7
4.3
3.1
3.4
3.2
1.9
5.0
4.7
3.2
4.1
3.2
2.4
11th
13th
17th
19th
1.53
1.386
0.774
0.558
2.55
2.31
1.29
0.93
3.773
2.107
1.519
6.391
3.569
2.573
12.86
7.181
5.177
18.48
10.32
7.440
-, - combination to provide an
23rd
25th
2.6
1.8
1.7
1.3
3.0
2.2
1.6
1.4
23rd
25th
0.468
0.324
0.78
0.54
1.274
0.882
2.158
1.494
4.342
3.006
6.240
4.320
Hide quick links:
Advertisement
Table of Contents
