Bender B93100735, Руководство пользователя

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Power Quality
51 PEM735_D00084_02_M_XXEN/06.2020
6.3.6 Harmonic voltages
Under normal operating conditions, during each period of one week, 95 % of the 10 min
mean r.m.s. values of each individual harmonic voltage must be less than or equal to the
values given in table 6.1. Resonances may cause higher voltages for an individual har-
monic.
Moreover, the THD of the supply voltage (including all harmonics up to the order 40)
must be ≤ 8 %.
Overview of the limits for individual harmonics
Tab. 6.1: Limits for individual harmonics
Note table 6.1: The 3n harmonics are highlighted. They contribute significantly to the
unwanted heating of the neutral conductor.
Harmonics order Percentage [%] Harmonics order Percentage [%]
2
2.0
3
5.0
4
1.0
5
6.0
6
0.5
7
5.0
8
0.5
9
1.5
10
0.5
11
3.5
12
0.5
13
3.0
14
0.5
15
0.5
16
0.5
17
2.0
18
0.5
19
1.5
20
0.5
21
0.5
22
0.5
23
1.5
24
0.5
25
1.5
No values are given for harmonics of order higher than 25, as they are usually low, but
largely unpredictable due to resonance effects.