Fault-tolerant permanent magnet machine with reconfigurable stator core slot flux paths

A permanent magnet (PM) machine comprising:

• a stator core portion;
• a rotor core portion;
• and a reconfigurable fault condition mechanism disposed solely within the stator core portion. the mechanism automatically reconfigurable to reduce fault currents associated with the PM machine during a fault condition, wherein the reconfigurable fault condition mechanism comprises a sliding shield disposed within a stator slot opening portion of the stator core portion, and further wherein the sliding shield comprises a dual-phase magnetic material.

A permanent magnet (PM) machine comprising a stator core portion having a fault condition mechanism disposed therein, the fault condition mechanism automatically reconfigurable to reduce internal heat associated with the PM machine during a fault condition, wherein the fault condition mechanism comprises at least one rotatable cylinder disposed within at least one slot opening of the stator core portion.

A permanent magnet (PM) machine comprising a stator core portion having a fault condition mechanism disposed therein, the fault condition mechanism automatically reconfigurable to reduce internal heat associated with the PM machine during a fault condition, wherein the fault condition mechanism comprises a plurality of cavities, each cavity associated with a stator core slot to impede a flux path though a respective stator core slot during a fault-free operating condition, and further wherein each cavity is filled with a ferrofluid to divert more flux away from a normal flux path through a back iron portion and create a lower reluctance flux path though a respective stator core slot during a PM machine fault condition.

A method of reconfiguring a permanent magnet (PM) machine upon detecting a fault condition, the method comprising the steps of:

• providing permanent magnet (PM) machine with a stator core comprising a reconfigurable fault condition mechanism disposed therein, the mechanism selected from a plurality of rotatable magnetically anisotropic cylinders disposed within stator core slots, a plurality of ferrofluid-fillable cavities associated with stator core slots, and a sliding shield within the stator core;
• and
• reconfiguring the fault condition mechanism to automatically reduce fault currents associated with the PM machine upon detection of a fault condition, wherein the step of reconfiguring the fault condition mechanism comprises filling the cavities with a ferrofluid during a PM machine fault condition, such that the filled cavities conduct a flux path though the stator core slots.