IPM ROTOR MAGNET SLOT GEOMETRY FOR IMPROVED HEAT TRANSFER

1 . A rotor, comprising:

a stack of metal laminations each having a plurality of magnet slots, the stacked laminations being substantially aligned with one another so that corresponding aligned magnet slots form longitudinal channels in the rotor, selected ones of the magnet slots having at least one feature protruding from at least one side thereof;

a plurality of magnets each having a side, each magnet being disposed in a respective one of the longitudinal channels; and

a thermal conductor connecting the side of one of the magnets with the side of one of the selected magnet slots having at least one protruding feature;

wherein the feature abuts and thereby spaces the magnet side from the side of the respective magnet slot.

2 . The rotor of claim 1 , wherein the metal laminations comprise a plurality of first and second laminations, and wherein a portion of the magnet slots each have the at least one feature in the first laminations and another portion of the magnet slots have the at least one feature in the second laminations.

3 . The rotor of claim 1 , wherein the selected ones of the magnet slots each have two long sides each having at least one feature protruding therefrom for abutting respective sides of the magnet.

4 . The rotor of claim 3 , wherein at least two of the laminations have a plurality of magnet slots that each include a pair of edge support projections along one of the long sides of the respective magnet slot, the edge support projections being structured for preventing lateral movement of a respective one of the magnets.

5 . The rotor of claim 4 , further comprising an insert placed between the edge support projections and the magnet.

6 . The rotor of claim 1 , wherein features of adjacent laminations of the stack interlock with one another.

7 . The rotor of claim 1 , wherein the thermal conductor substantially completely encapsulates the magnets within the respective longitudinal channels.

8 . The rotor of claim 1 , wherein each magnet slot has first and second sides in proximity to a magnet space, has a pair of edge support projections along the first side defining a lateral space, and has a protruding feature on the second side defining a first width between the first side and the protruding feature.

9 . The rotor of claim 8 , further comprising a protruding feature on the first side between the pair of edge support projections.

10 . The rotor of claim 8 , wherein the edge support projections are stepped, wherein space between the first width and the second side defines a second width.

11 . The rotor of claim 10 , further comprising at least one insert and a magnet, wherein the at least one insert is disposed between the magnet and at least one of the edge support projections.

12 . A method of facilitating heat transfer in a rotor, comprising:

forming a plurality of metal laminations each having a plurality of magnet slots, selected ones of the magnet slots having at least one feature protruding from at least one long side thereof;

stacking the laminations and thereby aligning the magnet slots to form longitudinal channels in the rotor;

placing magnets in the longitudinal channels, the magnets each having at least one long side in cross-section; and

providing a thermal conductor contiguously between one of the long magnet slot sides having at least one feature and the long side of the corresponding magnet.

13 . The method of claim 12 , wherein the placing of at least one of the magnets includes placing at least two features into abutment with the long side of the one magnet.

14 . The method of claim 13 , wherein the two features are axially displaced from one another.

15 . The method of claim 13 , wherein the two features are within the same magnet slot of one of the laminations.

16 . The method of claim 15 , wherein the placing of the thermal conductor includes flowing the thermal conductor to substantially completely encapsulate the magnet within the respective longitudinal channel.

17 . The method of claim 13 , further comprising adjusting an amount and respective locations of a plurality of the features within the longitudinal channels to correspondingly adjust a ratio of an amount of surface area of lamination metal contacting the magnets to an amount of surface area of the thermal conductor contacting the magnets.

18 . The method of claim 12 , further comprising adjusting an amount and respective locations of a plurality of the features within the longitudinal channels to correspondingly adjust a distribution of steel within the rotor core based on a distribution of heat from the magnets.

19 . A rotor, comprising:

a stack of metal laminations each having a plurality of magnet slots, the stacked laminations being substantially aligned with one another so that corresponding aligned magnet slots form longitudinal channels in the rotor, selected ones of the magnet slots having at least one feature in the periphery thereof;

a plurality of magnets each having a side, each magnet being disposed in a respective one of the longitudinal channels; and

a thermal conductor connecting the side of one of the magnets with the peripheral surface of one of the selected magnet slots having at least one protruding feature;

wherein the feature abuts and thereby spaces the magnet side from the peripheral side of the respective magnet slot.

20 . The rotor of claim 19 , wherein the feature is a notch.