App. B Japanese Guideline for Suppressing Harmonics by Customers Receiving High Voltage or Special High Voltage
A-16
Note: The correction coefficient is to be determined as a matter of consultation between the customer and
electric power company for the customers receiving the electric power over 2000 kW or from the
special high voltage lines.
(4) Degree of harmonics to be calculated
The higher the degree of harmonics, the lower the current flows. This is the property of harmonics
generated by inverters so that the inverters are covered by "The case not causing a special hazard" of the
term (3) of 3. in Appendix of the guideline.
Therefore, "It is sufficient that the 5th and 7th harmonic currents should be calculated."
[3] Examples of calculation
(1) Equivalent capacity
Table B-8
Example of loads Input capacity and
No. of inverters
Conversion
factor
Equivalent capacity
[Example 1] 400 V, 3.7 kW, 10 units
w/ AC reactor and DC
reactor
4.61 kVA ± 10 units K32 = 1.4 4.61±10±1.4 = 64.54 kVA
[Example 2] 400 V, 1.5 kW, 15 units
w/ AC reactor
2.93 kVA ± 15 units K34 = 1.8 2.93±15±1.8 = 79.11 kVA
Refer to Table B-2. Refer to Table B-3.
(2) Harmonic current every degrees
Example 1: 400 V, 3.7 kW, 10 units (w/ AC reactor), maximum availability: 0.55
Table B-9
Fundamental current
onto 6.6 kV lines (mA)
Harmonic current onto 6.6 kV lines (mA)
5th
(38%)
7th
(14.5%)
11th
(7.4%)
13th
(3.4%)
17th
(3.2%)
19th
(1.9%)
23th
(1.7%)
25th
(1.3%)
394±10 = 3940
3940±0.55 = 2167
823.5 314.2
Refer to Tables B-4 and
B-6.
Refer to Tables B-5.
Example 2: 400 V, 3.7 kW, 15 units (w/ AC and DC reactor), maximum availability: 0.55
Table B-10
Fundamental current onto
6.6 kV lines (mA)
Harmonic current onto 6.6 kV lines (mA)
5th
(28%)
7th
(9.1%)
11th
(7.2%)
13th
(4.1%)
17th
(3.2%)
19th
(2.4%)
23rd
(1.6%)
25th
(1.4%)
394±15 = 5910
5910±0.55 = 3250.5
910.1 295.8
Refer to Tables B-4 and
B-6.
Refer to Table B-5.
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