ABB ACS800-37-0170-3 - AC Voltage and Current Waveforms

The ACS800-37
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AC voltage and current waveforms
The AC current is sinusoidal at a unity power factor. The IGBT supply unit does not
generate characteristic current or voltage overtones like a traditional 6- or 12-pulse
bridge does.
The Total Harmonic Distortion (THD) in voltage depends slightly on the Short Circuit
Ratio in the Point of Common Coupling (PCC). The high-frequency switching and
high du/dt slightly distort the voltage waveform at the input of the converter.
Typical line current (i
U
) and phase voltage (u
U
) waveforms are shown below.
An example spectrum and THD value of the current at the input of the drive are
shown below. Each harmonic is presented in percent of nominal current. n denotes
the ordinal number of the harmonic.
I , U
u
U
i
U
t [ms]
0
1
2
3
4
5
6
7
8
9
10
THD3 5 7 9 1113151719212325272931333537394143454749
I [%]
n