49
3
3.1.4
Harmonic suppression guideline
Harmonic currents flow from the inverter to a power receiving point via a power transformer. The harmonic suppression
guideline was established to protect other consumers from these outgoing harmonic currents.
The three-phase 200V input specifications 3.7kW or less are previously covered by "Harmonic suppression guideline
for household appliances and general-purpose products" and other models are covered by "Harmonic suppression
guideline for consumers who receive high voltage or special high voltage". However, the general-purpose inverter has
been excluded from the target products covered by "Harmonic suppression guideline for household appliances and
general-purpose products" in January 2004. Later, this guideline was repealed on September 6, 2004. All capacities of
all models are now target products of "Harmonic suppression guideline for consumers who receive high voltage or
special high voltage".
"Guideline for specific consumers"
This guideline sets forth the maximum values of harmonic currents outgoing from a high-voltage or especially high-
voltage consumer who will install, add or renew harmonic generating equipment. If any of the maximum values is
exceeded, this guideline requires that consumer to take certain suppression measures.
(1) Application of the harmonic suppression guideline for specific consumers
Table 1 Maximum Values of Outgoing Harmonic Currents per 1kW Contract Power
Received Power
Voltage
5th
7th
11th
13th
17th
19th
23rd
Over 23rd
6.6kV
3.5
2.5
1.6
1.3
1.0
0.9
0.76
0.70
22kV
1.8
1.3
0.82
0.69
0.53
0.47
0.39
0.36
33kV
1.2
0.86
0.55
0.46
0.35
0.32
0.26
0.24
Table 2 Conversion factors for FR-F700 series
Class
Circuit Type
Conversion Factor (Ki)
3
Three-phase bridge
(Capacitor smoothing)
Without reactor
K31 = 3.4
With reactor (AC side)
K32 = 1.8
With reactor (DC side)
K33 = 1.8
With reactor (AC, DC sides)
K34 = 1.4
5
Self-exciting three-phase bridge
When high power factor converter is used
K5 = 0
Table 3 Equivalent Capacity Limits
Received Power Voltage
Reference Capacity
6.6kV
50kVA
22/33kV
300kVA
66kV or more
2000kVA
Table 4 Harmonic content (Values of the fundamental current is 100%)
Reactor
5th
7th
11th
13th
17th
19th
23rd
25th
Not used
65
41
8.5
7.7
4.3
3.1
2.6
1.8
Used (AC side)
38
14.5
7.4
3.4
3.2
1.9
1.7
1.3
Used (DC side)
30
13
8.4
5.0
4.7
3.2
3.0
2.2
Used (AC, DC sides)
28
9.1
7.2
4.1
3.2
2.4
1.6
1.4
Install, add or renew
equipment
Calculation of equivalent
capacity total
Equivalent
capacity total
Calculation of outgoing
harmonic current
Not more than
harmonic current upper
limit?
Harmonic suppression
measures unnecessary
Harmonic suppression
measures necessary
Equal to or less
than upper limit
More than upper limit
Above reference
capacity
Equal to or less
than reference
capacity