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I_A
I_B
I_C
I3P
Distortion
measure-
ment
Total
harmonic
distortion
Total
demand
distortion
Harmonic
calculation
SMNTHD_A
SMNTHD_B
SMNTHD_C
SMNTDD_A
SMNTDD_B
SMNTDD_C
SMNDC_A
SMNDC_B
SMNDC_C
SMNH01_A
SMNH01_B
SMNH01_C
SMNH02_A
SMNH02_B
SMNH02_C
...un
til
hmax
Figure 960: Functional module diagram
10.1.5.1
Distortion measurement
The Distortion measurement module measures harmonics up to the 11
th
harmonic.
The filter used for harmonics includes a spectrum of frequencies near each
harmonic frequency. FFT for one period is used. The resulting frequency spectrum is
wider than in a harmonic subgroup. An anti-aliasing filter is used.
10.1.5.2
Total harmonic distortion
The total harmonic distortion THD is calculated from the measured harmonic
components with the formula
THD
I
I
h
h
n
=
=
∑
1
2
2
(Equation 390)
I
h
h
th
harmonic component
I
1
Fundamental frequency current (1
st
harmonic)
n
Number of harmonics
1MRS759142 F
Power quality measurement functions
REX640
Technical Manual
1809
Содержание RELION REX640
Страница 1: ... RELION PROTECTION AND CONTROL REX640 Technical Manual ...
Страница 2: ......
Страница 3: ...Document ID 1MRS759142 Issued 2023 02 07 Revision F Copyright 2023 ABB All rights reserved ...
Страница 167: ...Figure 62 Signal outputs in power supply module 1MRS759142 F Basic functions REX640 Technical Manual 167 ...
Страница 184: ...Figure 84 mA channels working as mA outputs Basic functions 1MRS759142 F 184 REX640 Technical Manual ...
Страница 1868: ...Figure 989 ANSI extremely inverse time characteristics General function block features 1MRS759142 F 1868 REX640 Technical Manual ...
Страница 1869: ...Figure 990 ANSI very inverse time characteristics 1MRS759142 F General function block features REX640 Technical Manual 1869 ...
Страница 1870: ...Figure 991 ANSI normal inverse time characteristics General function block features 1MRS759142 F 1870 REX640 Technical Manual ...
Страница 1874: ...Figure 995 ANSI long time inverse time characteristics General function block features 1MRS759142 F 1874 REX640 Technical Manual ...
Страница 1875: ...Figure 996 IEC normal inverse time characteristics 1MRS759142 F General function block features REX640 Technical Manual 1875 ...
Страница 1876: ...Figure 997 IEC very inverse time characteristics General function block features 1MRS759142 F 1876 REX640 Technical Manual ...
Страница 1877: ...Figure 998 IEC inverse time characteristics 1MRS759142 F General function block features REX640 Technical Manual 1877 ...
Страница 1878: ...Figure 999 IEC extremely inverse time characteristics General function block features 1MRS759142 F 1878 REX640 Technical Manual ...
Страница 1882: ...Figure 1002 RI type inverse time characteristics General function block features 1MRS759142 F 1882 REX640 Technical Manual ...
Страница 1885: ...Figure 1004 UK rectifier inverse time characteristic 1MRS759142 F General function block features REX640 Technical Manual 1885 ...
Страница 1959: ......