Excitation Unit (Exu); Exu D4 Frame Cabinet (A) And Exu D5 Frame Cabinet (B) - ABB ACS6000 User Manual

3.3.5

Excitation unit (EXU)

The EXU supplies a synchronous motor with excitation power. The EXU is
available for the following excitation methods:
• Brush excitation (DC excitation): Uses a DCS800 AC-to-DC converter
which is supplied by the mains. The converter controls the direct
current for generating the magnetic field. Brushes and slip-rings
feed the DC current to the rotor.
• Brushless excitation (AC excitation): Uses a three-phase DCS800 AC-
power controller. The power controller feeds an exciter which is
mounted on the shaft of the main motor. The rotating armature of
the exciter supplies a rectifier which generates the DC current for
producing the magnetic field in the synchronous motor.
Note: For more information, see "Air-cooled excitation units, brush
brushless excitation technical data" (3BHS299399 E01).
A A
1
2
2
Figure 3-30 EXU D4 frame cabinet (A) and EXU D5 frame cabinet (B)
(1) Ground fault detection device
(optional)
(2) Fuses
(3) Control compartment
(4) Fan units
3BHS212794 E01 REV M
03 POWER ELECTRONICS AND CABINET FEATURES
3 3
4
7
5
6
(5) DCS800 D4 unit
(6) Overvoltage protection (not
shown in A)
(7) DCS800 D5 unit
ACS6000 USER MANUAL
B B
1
6
4
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