PM offset external rotor radial mixed magnetic bearing with redundant structure

The invention relates to an external rotor radial mixing magnetic bearing biased with permanent magnets, which is provided with redundant structure, comprising left-right external magnetic conductive rings, permanent magnet, left-right rotor cores, left-right stator cores, excitation coil and internal magnetic conductive ring. Left (right) stator core and internal magnetic conductive ring are set in left (right) rotor core in turn. The internal magnetic ring is connected with left-right stator cores. There is air gap between inner face of rotor core and outer face of stator core. Left-right stator cores constitute sixteen magnetic poles and excitation coil is winded on each magnetic pole. They are connected by internal magnetic conductive ring. The permanent magnet is set between left and right external magnetic conductive rings. Two groups of stator poles of redundancy with each other are constituted by not-adjacent four magnetic poles of left stator core, not-adjacent four magnetic poles of right stator core and the excitation coil on them. In the whole device two radial mixing magnetic bearings of redundancy with each other are constituted. The invention makes the structure of external rotor radial mixing magnetic bearing realize redundant. When one radial mixing magnetic bearing is failure, another can work normally so as to improve the stability of magnetic bearing system obviously.