Project Title:

Magnetic Bearings for Miniature, High-Speed Turbomachines

09.12-3800A
NAS5-30854
Magnetic Bearings for Miniature, High-Speed
	Turbomachines
Creare, Inc.
	P.O. Box 71
	Hanover, NH 03755
		Herbert Sixsmith
(603-643-3800)

Abstract:

	This project is aimed at the development of a novel electromagnetic (E-M) bearing
system specifically for miniature, high-speed turbomachines used in spaceborne turbo-Brayton
cryocoolers. Compared with gas bearings currently in use, E-M bearings provide greater
ruggedness and will allow for operation at lower temperatures and in vacuum environments.
These attributes offer potential improvements in cryocooler efficiency and reliability,
particularly at the temperatures and refrigeration capacities associated with surveillance
sensors. In this project, the technology of active E-M bearings developed for large
shaft sizes will be extended to miniature turbomachines. The key challenge is the
development of miniature shaft position sensors that are needed to control the bearing
force. In Phase I, an E-M bearing using a novel capacitive sensor will be demonstrated.
The detailed design, development, and demonstration of a complete miniature E-M bearing
system in a prototype turbomachine is planned for Phase II.

Potential Commercial Application:

Potential Commercial Applications: Proven E-M bearing technology for miniature, high-speed
machines will have immediate benefits in advancing the efficiency and reliability
of low-power cryocoolers that are needed for spaceborne surveillance sensors.