| 摘要 |
PCT No. PCT/FR95/00231 Sec. 371 Date Aug. 27, 1996 Sec. 102(e) Date Aug. 27, 1996 PCT Filed Feb. 28, 1995 PCT Pub. No. WO95/23297 PCT Pub. Date Aug. 31, 1995An active magnetic bearing with auto position-detection includes first and second opposing electromagnets disposed on opposite sides of a ferromagnetic body (1) suspended without contract with the electromagnets. The bearing includes inductive type position detectors which are constituted directly by coils (11, 21) of the first and second electromagnets. A mechanism (14; 24) is provided for injecting a sinusoidal current I0 sin omega t of constant amplitude I0, of angular frequency omega , and of identical phase, simultaneously to the inputs of power amplifiers (13, 23) powering the coils (11, 21) of the first and second opposing electromagnets in superposition with the main currents from the servo-control circuits (31, 32). Circuits (41 to 44) serve to extract the position information which determines the magnitude of the main current to be applied by the servo-control circuits (31, 32) to the power amplifiers (13, 23) directly from the voltages u1, u2 across the terminals of the excitation coils (11, 21) as measured at the frequency of the sinusoidal current constituting a carrier of angular frequency omega .
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