ABB ACS5000, User Manual

Page: 57 / 186

3BHS799208 E01 REV E ACS5000 WATER-COOLED USER MANUAL 57/186
03 POWER ELECTRONICS AND CABINET FEATURES
3.7 EXU – Excitation unit (optional)
The EXU supplies a synchronous motor with excitation power. The EXU is
available for the following excitation methods:
• Brush excitation (DC excitation):
Brush excitation uses a DCS800 AC-
to-DC converter (see figure below) 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):
Brushless excitation uses a
three-phase DCS800 AC-power controller (see figure below). 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.
Figure 3-19 EXU
(1) AC-to-DC converter
(2) Output disconnector (option) (3) AC power controller
1
2
3