Active Magnetic Bearings
MECOS – a member of the
MAN Diesel & Turbo Group
Working Principles of
Advantages of Active
Active Magnetic Bearings Magnetic Bearings
(AMB)
Active damping of rotor vibrations
Unlimited starts / stops
„Instant“ availability:
only a few seconds from
stand-by mode to full speed
Operable in process gas stream
Oil-free operation:
no contamination to process gas
Extremely low power consumption:
typically 2 - 5 kW
An Active Magnetic Bearing (AMB) is an
electro-magnetic system for controlling the
position of a rotor, e.g. in a turbomachine.
The active magnetic bearing (also called
“bearing stator”) comprises a number of
electro-magnets, positioned around the rotor,
which generate attracting forces to maintain
the position of the rotor relative to the stator. An advanced electronic control system
adjusts the power supply and, thereby, the
magnetic forces generated, to ensure stable
rotation of the rotor, independent of the forces
induced by the machinery process.
Magnetic bearings require no lubricants,
are frictionless and mechanically wear-free.
They have the capability of tailoring bearing
characteristics to optimise operation.
Their use in turbomachinery reduces process
down time, lengthens machine life, enables
more efficient high-speed machines, eliminates gears and reduces maintenance costs.
Load capacity up to 7 bars
UPS for safe operation included
No wearing parts in normal operation
Integrated “Machine Monitoring System”
Active Magnetic Bearings
Basic Components of AMB
Radial Bearing
Each radial bearing stator consists of several pairs of electro-magnets, arranged radially around the rotor. The stator’s counterpart,
the rotor elements, are steel laminations fitted to the rotor. The radial bearings are designed to position the rotor radially.
All data provided in this document is non-binding. This data serves informational purposes
only and is especially not guaranteed in any
way. Depending on the subsequent specific
individual projects, the relevant data may be
subject to changes and will be assessed and
determined individually for each project. This
will depend on the particular characteristics of
each individual project, especially specific site
and operational conditions.
Copyright © MAN Diesel & Turbo Schweiz AG
CH-03-2013
applied, such as inductive, eddy current and
magnetic, depending on the application and
system performance requirements.
Touch-down Bearing
The touch-down bearings support the
rotor during stand-still or in the very unlikely event of a power electronics’ failure.
They also prevent damage to the magnetic
bearings during overload or in the event of
system fault.
Thrust Bearing
The thrust bearing uses two ring-shaped
magnets positioned on both sides of the socalled “thrust disc”. The thrust disc is a flat,
solid, ferromagnetic disc attached to the rotor. The axial bearing positions the rotor in
the axial direction.
Position Sensor
The position sensors detect the axial and
radial position, as well as the movement of
the rotor during stand-by and operation. Alternative, established technologies can be
Control System Cabinet
The control system uses the inputs from
the position sensors (input signals) to determine the actual rotor position. It then
adjusts the power (output signal) to the individual magnets thus ensuring that the rotor stays in the desired position. The main
components of the control system are the
processor, the amplifiers for the individual
magnetic bearings, the UPS and interfaces
to connect with other systems. The control
system ensures safe operation of the magnetic bearing system under all conditions,
such as start-up, normal operation and
shut-down.
MECOS AG
Industriestrasse 26
8404 Winterthur, Switzerland
Phone +41 52 235-1414
Fax
+41 52 235-1424
www.mecos.com
MAN Diesel & Turbo
Schweiz AG
Hardstrasse 319
8005 Zürich, Switzerland
Phone +41 44 278-2211
Fax
+41 44 278-2261
www.mandieselturbo.com