Helium Cold Compressor with Active Magnetic Bearings

The number of Active Magnetic Bearing (AMB) equipped rotating machines has been increasing remarkably in the last few years. It can be pointed out that the turbo molecular vacuum pump (TMP) is the most successful application for AMB system as a series production. Furthermore, machine-tool spindle, flywheel energy storage system, general-purpose gas blower and other turbo machinery are also interesting application fields for AMB. In 1997, Ishikawajima heavy Industry (IHI) installed helium cold compressor prototype with 5 axes controlled AMB spindle produced by KOYO Seiko Co., LTD in the CERN (Geneva, Switzerland). In this paper the above mentioned 5 axes controlled AMB spindle are reported associating to “Digitally controlled AMB”.