In order to reduce the costs, radial active magnetic bearings have been proposed which consist of only three electromagnets. Unfortunately it is not possible to operate the three coils with a 3-phase power converter, since the sum of the coil currents does not equal zero. Three independent amplifier channels are needed for the control of this arrangement. In this paper a radial magnetic bearing is proposed which can be operated by commercial 3-phase power amplifiers. By the use of an arrangement of permanent magnets it is possible to make the sum of the three phase currents become zero. Some problems related to this bearing arrangement as well as solutions are discussed and shown using the example of two prototype bearings.

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