ABB ACS880 Series, Руководство по планированию электроснабжения

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Examining the compatibility of the motor and drive
Use asynchronous AC induction motors, permanent magnet synchronous motors, AC
induction servomotors or ABB synchronous reluctance motors (SynRM motors) with the
drive.
Select the motor size and drive type from the rating table on basis of the AC line voltage
and motor load. You can find the rating table in the appropriate drive or inverter unit hardware
manual. You can also use the DriveSize PC tool.
Make sure that the motor withstands the maximum peak voltage in the motor terminals. See
Requirements table (page 18) . For basics of protecting the motor insulation and bearings
in drive systems, see Protecting the motor insulation and bearings (page 18) .
Note:
• Consult the motor manufacturer before using a motor whose nominal voltage differs
from the AC line voltage connected to the drive input.
• The voltage peaks at the motor terminals are relative to the supply voltage of the drive,
not the drive output voltage.
• If the motor and drive are not of the same size, consider the operation limits of the drive
control program for the motor nominal voltage and current. See the appropriate
parameters in the firmware manual.
￭ Protecting the motor insulation and bearings
The drive employs modern IGBT inverter technology. Regardless of frequency, the drive
output comprises pulses of approximately the drive DC bus voltage with a very short rise
time. The pulse voltage can almost double at the motor terminals, depending on the
attenuation and reflection properties of the motor cable and the terminals. This can cause
additional stress on the motor and motor cable insulation.
Modern variable speed drives with their fast rising voltage pulses and high switching
frequencies can generate current pulses that flow through the motor bearings. This can
gradually erode the bearing races and rolling elements.
d u /d t filters protect motor insulation system and reduce bearing currents. Common mode
filters mainly reduce bearing currents. Insulated N-end (non-drive end) bearings protect the
motor bearings.
￭ Requirements table
These tables show how to select the motor insulation system and when a drive d u /d t and
common mode filters and insulated N-end (non-drive end) motor bearings are required.
Ignoring the requirements or improper installation may shorten motor life or damage the
motor bearings and voids the warranty.
18 Electrical planning guidelines