13.10 Calculation Formula
204
Harmonic Voltage (Uharm), Harmonic Current (Iharm), Inter-harmonic voltage
(Uiharm), Inter-harmonic current (Iiharm)
Single Phase 2-wire
1P2W
Single
Phase
3-wire
1P3W
3-Phase,
3-Wire,
2-Measure-
ment
3P3W2M
3-Phase,
3-Wire,
3-Measure-
ment
3P3W3M
3-Phase,
4-Wire
3P4W
Uharm[Vrms]=Uck
(including adjacent inter-harmonic com-
ponents)
U
1k
U
4k
U’ck=
Uck=
U
1k
U
2k
U
4k
U
12k
U
32k
U
4k
U
12k
U
23k
U
31k
U
4k
U
1k
U
2k
U
3k
U
4k
• For 3-phase 3-wire connections, indicates the result of harmonic calculations using the
line voltage. For 3-phase 4-wire connections, indicates the result of harmonic calculations
using the phase voltage.
• The harmonic voltage content percentage is calculated by dividing the harmonic voltage
component for the specified order by the fundamental voltage component and multiplying
by 100.
• For 60 Hz measurement, the value 10 in the formula is replaced with 12. For 400 Hz mea-
surement, the value 10 in the formula is replaced with 80.
• When K = 0, the Uc0 component is treated as DC for order 0.
Iharm[Arms]=Ick
(including adjacent inter-harmonic com-
ponents)
I
1k
I
4k
I’ck=
Ick=
I
1k
I
2k
I
4k
I
1k
I
2k
I
4k
I
1k
I
2k
I
3k
I
4k
I
1k
I
2k
I
3k
I
4k
• The harmonic current content percentage is calculated by dividing the harmonic current
component for the specified order by the fundamental current component and multiplying
by 100.
• When using 60 Hz, the number "10" in the expression above is "12." When using 400 Hz,
the number "10" in the expression above is "80."
• When K = 0, the Ic0 component is treated as DC for order 0.
Uiharm[Vrms]=Uck U
1k
U
4k
U’ck=
Uck=
U
1k
U
2k
U
4k
U
12k
U
32k
U
4k
U
12k
U
23k
U
31k
U
4k
U
1k
U
2k
U
3k
U
4k
• The values 3 and -3 in the formula apply to 50 Hz measurement and are replaced with 4
and -4 for 60 Hz measurement. In the formula, k = 0.5, 1.5, 2.5, 3.5,...
• For 3-phase 3-wire connections, indicates the result of harmonic calculations using the
line voltage. For 3-phase 4-wire connections, indicates the result of harmonic calculations
using the phase voltage.
• The inter-harmonic voltage content percentage is calculated by dividing the inter-harmonic
voltage component for the specified order by the fundamental voltage component and
multiplying by 100.
• For 60 Hz measurement, the value 10 in the formula is replaced with 12.