END TURN CONFIGURATION OF AN ELECTRIC MACHINE

• US 20100019609A1
• Filed: 07/01/2009
• Published: 01/28/2010
• Est. Priority Date: 07/28/2008
• Status: Abandoned Application

• Current Assignee: Direct Drive Systems Inc. (TechnipFMC, plc)
• Original Assignee: Direct Drive Systems Inc. (TechnipFMC, plc)
• Inventors: Saban, Daniel M., Stout, John, Guedes-Pinto, Paulo
• Application Number:
  US12/496,488
• Publication Number:
  US 20100019609A1
• Time in Patent Office: Days
• US Class Current: 310/198
• CPC Class Codes: H02K 1/02 characterised by the magnetic material
• CPC Class Codes: H02K 1/165 Shape, form or location of the slots
• CPC Class Codes: H02K 1/278 Surface mounted magnets; Inset magnets
• CPC Class Codes: H02K 15/12 Impregnating, heating or drying of windings, stators, rotors or machines
• CPC Class Codes: H02K 3/12 arranged in slots
• CPC Class Codes: H02K 3/24 with channels or ducts for cooling medium between the conductors
• CPC Class Codes: H02K 3/28 Layout of windings or of connections between windings windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32
• CPC Class Codes: H02K 3/487 Slot-closing devices
• CPC Class Codes: H02K 3/50 Fastening of winding heads, equalising connectors, or connections thereto
• CPC Class Codes: H02K 5/1285 of the submersible type
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine
• CPC Class Codes: Y10T 29/49012 Rotor

Abstract

A stator for an electric machine includes multiple conductive coils. Each coil defines a loop that extends axially through the elongate core, exits the core through an end face, and reenters the core through the end face. A first subset of the coils collectively form a first radial layer axially exterior the core and a third radial layer axially exterior the core. Each coil in the first subset resides in both the first layer and the third layer. A second subset of the coils collectively forms a second radial layer axially exterior the core and a fourth radial layer axially exterior the core. Each coil in the second subset residing in both the second layer and the fourth layer.

Claims

1. A stator for an electric machine, the stator comprising:

an elongate core having an end face and an opposing end face, the elongate core adapted to internally receive a rotor of an electric machine;

a plurality of conductive coils, each coil defining a loop that extends axially through the elongate core, exits the core through the end face, and reenters the core through the end face, a first subset of the coils collectively forming a first radial layer axially exterior the core and a third radial layer axially exterior the core, each coil in the first subset residing in both the first layer and the third layer, a second subset of the coils collectively forming a second radial layer axially exterior the core and a fourth radial layer axially exterior the core, each coil in the second subset residing in both the second layer and the fourth layer, the second layer residing radially between the first and third layers, the third layer residing radially between the second and fourth layers.

2. The stator of claim 1, wherein the loop defined by each coil in the first subset exits the core through the end face at an exit location in the first radial layer and reenters the core through the end face at a reentry location in the third radial layer, and wherein the loop defined by each coil in the second subset exits the core through the end face at an exit location in the second radial layer, and reenters the core through the end face at a reentry location in the fourth radial layer.

3. The stator of claim 1, wherein the plurality of coils forms two radial layers in the elongate core, and each of the coils resides in both radial layers in the elongate core.

4. The stator of claim 3, wherein the two radial layers in the elongate core define two radii on the end face including a first radius and a second radius, the loop defined by each coil in the first subset exits the core through the end face at an exit location on the first radius, turns toward the first radial layer, extends through the first radial layer, turns toward the third radial layer, extends through the third radial layer, and reenters the core through the end face at a reentry location on the second radius.

5. The stator of claim 4, wherein the loop defined by each coil in the second subset exits the core through the end face at an exit location on the first radius, turns toward the second radial layer, extends through the second radial layer, turns toward the fourth radial layer, extends through the fourth radial layer, and reenters the core through the end face at a reentry location on the second radius.

6. The stator of claim 1, wherein the core comprises a plurality of slots to carry the coils, a first subset of the slots each carry two of the first subset of coils, and a second subset of the slots each carry two of the second subset of coils.

7. The stator of claim 6, wherein a radial distance between two coils in each slot and an azimuthal distance between two sides of the slot define a gap in the slot.

8. The stator of claim 6, wherein first subset of slots and the second subset of slots all have substantially equal radial depths.

9. The stator of claim 6, wherein an inner-most radial layer comprises the fourth radial layer, an outer-most radial layer comprises the first radial layer, the first subset of slots have a first radial depth, the second subset of slots have a second radial depth, and the second radial depth is less than the first radial depth.

10. A stator for an electric machine, the stator comprising:

an elongate core adapted to internally receive a rotor of an electric machine;

a first plurality of coils arranged in a first lap winding configuration and forming a first plurality of end turns that each extend through a first radial layer of end turns and a third radial layer of end turns; and

a second plurality of coils arranged in a second lap winding configuration and forming a second plurality of end turns that each extend through a second radial layer of end turns and a fourth radial layer of end turns, the second layer residing radially between the first and third layers, the third layer residing radially between the second and fourth radial layers.

11. The stator of claim 10, wherein the first plurality of coils and the second plurality of coils collectively form two radial layers in the core, wherein each of the first plurality of coils and each of the second plurality of coils resides in both of the two radial layers in the core.

12. The stator of claim 10, wherein the first plurality of coils collectively form four radial layers in the core, the first plurality of coils reside in a first pair of the four radial layers in the core, the second plurality of coils reside in a second pair of the four radial layers in the core.

13. The stator of claim 12, wherein the stator defines an array of slots, the first plurality of coils resides in a first subset of the slots, the second plurality of coils resides in a second subset of the slots.

14. The stator of claim 13, wherein two of the coils reside in each slot, and a radial spacing between the coils in each slot define a radial gap in the slot.

15. The stator of claim 13, wherein the first subset of slots have a first radial depth and the second subset of slots have a second radial depth that is less than the first radial depth.

16. A method of making a stator of an electric machine, the method comprising:

installing a first plurality of coils in a core of a stator, the first plurality of coils collectively forming a first radial layer of end turns and a third radial layer of end turns axially external the core, each of the first plurality of coils defining a loop that extends axially through the core, exits the core through the end face, extends through the first radial layer, extends through the third radial layer, and reenters the core through the end face; and

installing a second plurality of coils in the core of the stator, the second plurality of coils collectively forming a second radial layer of end turns and a fourth radial layer of end turns axially external the core, each of the second plurality of coils defining a loop that extends axially through the core, exits the core through the end face, extends through the second radial layer, extends through the fourth radial layer, and reenters the core through the end face;

wherein the second radial layer resides radially between the first and third radial layers, and the third layer resides radially between the second and fourth radial layers.

17. The method of claim 16, further comprising coupling the first plurality of coils to the second plurality of coils to form a three-phase conductive winding.

18. The method of claim 16, further comprising operating the electric machine as a multi-pole electric machine.

19. The method of claim 16, wherein installing at least one of the first plurality of coils or the second plurality of coils comprises forming a winding structure outside of the core and installing the formed winding structure in the core.

20. The method of claim 16, wherein installing at least one of the first plurality of coils or the second plurality of coils comprises installing each of the plurality of coils by successively forming individual turns of the coil in the core of the stator.

21. The method of claim 16, wherein installing the first plurality of coils and installing the second plurality of coils comprises simultaneously installing the first plurality of coils and the second plurality of coils.