Specifying magnetic bearings

Turbomachinery International, Jan/Feb 2007 by Richard, Philipp, Larsonneur, Ren�

Enhancing measurements

The built-in measurement capabilities can do more. An integrated measurement system [1] can offer:

* SISO and MIMO measurement of arbitrary open- and closed-loop transfer functions at any rotor speed

* Identification of gyroscopic effects and generation of Campbell diagrams (frequency vs operating speed plots) automatically

* Multi-variable signal injection with freely selectable frequency, amplitude, phase, and injection point

* Continuous monitoring and analysis of system states, such as displacement, temperature or balancing conditions

* A real-time and multi-channel oscilloscope with built-in trigger, step response measurement and FFT computation functionalities

* On-line rotor balancing tool

* Versatile control parameter design and simple download of complex parameter structures

An integrated measurement system has the flexibility to accomplish tasks that can be complex and time-consuming. For example, it is possible to continuously monitor bending mode frequencies as part of a preventive maintenance program and detect undesirable changes at an early stage.

Footnote:

[1] MECOS (www.mecos.com) offers an integrated measurement system that incorporates the capabilities and can be embedded on Matlab, a commonly used software.

PHILIPP RICHARD AND REN� LARSONNEUR

MECOS MAGNETIC BEARINGS

Authors:

Philipp Richard is the product manager at MECOS TRAXLER AG (www.mecos.com). A power electronics engineer, he helped develop an integrated magnetic bearing and motor controller.

Ren� Larsonneur is responsible for the development of control concepts and software tools at MECOS. He is a member of the ISO technical committee for the new magnetic bearing standard. 2007 marks his 25th year in magnetic bearings.