ABB ACS2000 AFE 1MVA - EMC Filter; INU - Inverter Unit

41 ACS2000 AFE 1MVA UM 3BHS297030 ZAB E01 REV. J
2.3.5 INU - Inverter unit
The INU converts the DC voltage to the required AC
motor voltage and frequency.
Like the AFE, the INU is an active 3-phase unit with
the same electrical configuration. The unit is
designed as a self-commutated, 5-level voltage
source inverter. As a result of the multi-level topol-
ogy, the drive produces an optimum number of
switching levels - nine levels, phase to phase.
The resulting waveforms permit the application of
standard motors.
The INU is composed of three identical phase mod-
ules (see Phase module). The phase modules can
be extracted from the cabinet to facilitate mainte-
nance and service on the INU.
2.3.6 EMC filter
The INU includes a three-phase du/dt filter con-
nected to its AC output. The filter chokes (2-12: 1),
resistors (2-10: 2), and capacitors (2-10: 3) protect
the motor against excessive voltage slopes (du/dt
is limited to 500 V/?s).
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References
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2-11 INU - Inverter unit
—
2-12 EMC filter
—
2-11
Phase module of phase U2
Phase module of phase V2
Phase module of phase W2
1
2
3
INUDC link
DC+
NP
DC-
U2
V2
W2
EMC filter
to NP
—
2-12
1
2
3
1
2
3
P
P

P
P
P

P
10000 V
5000 V
- 5000 V
- 10000 V


P

P
P




10000 V
5000 V
- 5000 V
- 10000 V
Time