AMBIT: Active magnetic bearings in aircraft turbo-machinery

• Research unit: EU RFP
• Project number: 97.0289-1

Key words (English)

Active magnetic bearings; high temperature; turbomachinery

Alternative project number (English)

EU project number: BRPR-CT98-0623

Research programs (English)

EU-programme: 4. Frame Research Programme - 2.1 Industrial and materials technologies

Short description (English)

See abstract

Partners and International Organizations (English)

Imperial College (UK), Technische Univ. Darmstadt (D), Eidgenössische Technische Hochschule Zürich (CH), Mecos Traxler AG (CH), MTU Munich (D), Austrian Energy and Environment, SGP/Waagner GmbH (A), Turbomeca (F)

Abstract (English)

One of the primary objectives of AMBIT is to investigate and to demonstrate the feasibility of an active magnetic suspension that works at high temperatures up to 540°C. ETH has been the task leader of this subject. ETH has built a one-degree-of-freedom high temperature AMB rig and a five-degree-of-freedom high temperature prototype. The AMB has satisfied the temperature requirements.
The investigation on the performance of high temperature AMB has been carried out on our HT AMB prototype. First, the force-current-displacement relationship of high temperature AMB was investigated. The simulation model and a test method have been developed. Second, the magnetic and mechanical properties of the special magnetic materials were investigated and included into the simulation model. The simulations are consistent with the experimental results. The bearing works very well at temperatures up to 540oC. Then, the load capacity, and the temperature increase inside the coils were evaluated and tested at different temperatures. We noticed that for an extended time period, the overheating under heavy load can cause short-circuiting problems inside the coils. These problems should be considered seriously in the design for future HT AMB applications. Design concepts and suggestions for solving these problems were investigated. Finally, the dynamic performance of the system and the controller at high temperatures were demonstrated. ETH has also made contributions on the design and testing of retainer bearings. There are already some promising results on the theoretical modelling of touchdown dynamics as well as the stress and thermal simulation of retainer bearings.
The HT AMB demonstrator prototype was exhibited at the 7th International Symposium on Magnetic Bearings (ISMB-7) in Zurich and at the exploitation meeting of AMBIT in Darmstadt, Germany. The participants from industry showed great interest in our achievements.
The project ended successfully. Due to the promising results and the good cooperation of the partners, a follow-up project named MAGFLY has been accepted by the EU in the meantime.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 97.0289-1