ABB
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ABB | Motors and Generators
| Synchronous motors
Fixed and variable speed motors tailored
for each specific application
Fixed speed motors
Fixed speed synchronous motors are typically used in
applications such as compressors, fans, pumps, wood
grinders and refiners.
In each case we utilize advanced software tools to optimize
the motor design for the specific application and ensure that
the chosen starting method is appropriate. The results of this
work are processed into an easy-to-understand format and
incorporated into the technical specification we provide with
each proposal.
We can engineer the motor to develop sufficient torque for
smooth starting and acceleration with the starting current
limited typically to 350 – 500% of the rated value. If this will
result in unacceptable line voltage drops then we can
investigate alternative starting methods.
The main factors to be considered in selecting the starting
method are the customer’s requirements, network capability
and the demands of the process. The starting methods
most commonly used for fixed speed synchronous motors
are direct-on-line (DOL), reactor, autotransformer, load
commutated inverter (LCI or ‘soft starter’), capacitor and
reactor capacitor.
Variable speed motors
Variable speed synchronous motors are typically used in
demanding applications in process industries, and applications
where variable speed delivers clear benefits. Rolling mills,
mine hoists, pumps, and compressors are examples of
variable speed applications. Synchronous motors with
variable speed drives (VSDs) are also commonly used in
the main propulsion system in vessels. In applications such
as extruders, compressors and pumps, optimized electrical
drive systems based on variable speed motors can provide
considerable energy savings.
We supply motors and drives that meet torque requirements
over the entire operating range, from zero to maximum
process speed. This ensures smooth starting, acceleration
and operation. For the optimum variable speed solution, we
have optimized ABB motor-drive packages: ABB synchronous
motor combined with ABB load commutated inverter or with
ABB voltage source inverter, e.g. ACS5000 or ACS6000.
Our engineering and
application know-how ensures that all
components in electrical drive packages, particularly the
converter-motor interface, are optimally integrated to meet the
needs of the process. Benefits include special converter-fed
motor designs, increased efficiency and improved torque
production capabilities.
M
M
DOL
Reactor
M
M
Autotrafo
Capacitor
M
M
LCI/Frequency converter
Reactor capacitor
Typical starting methods for fixed speed synchronous motors.
We always use specialized software tools to optimize
the motor design with the converter type best suited for
the application. All common converter types are supported:
load commutated inverter (LCI), cycloconverter (C) and
voltage source inverter (VSI).