SLOT CONFIGURATION OF AN ELECTRIC MACHINE

• US 20100019589A1
• Filed: 07/01/2009
• Published: 01/28/2010
• Est. Priority Date: 07/28/2008
• Status: Active Grant

• Current Assignee: FMC Technologies Incorporated (TechnipFMC, plc)
• Original Assignee: Direct Drive Systems Inc. (TechnipFMC, plc)
• Inventors: Saban, Daniel M., Stout, John, Guedes-Pinto, Paulo
• Granted Patent: US 8,253,298 B2
• Time in Patent Office: Days
• US Class Current: 310/52
• 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 includes an elongate core defining an inner volume to receive a rotor of an electric machine. The core includes a yoke and an array of teeth extending from the yoke toward the inner volume. The array of teeth defines slots between each pair of adjacent teeth in the array. Each slot includes a first slot region adapted to hold at least a portion of a conductive winding and a second slot region adapted to hold at least a portion of a conductive winding. The first slot region is defined by two non-parallel opposing slot side portions, and the second slot region is defined by two parallel opposing slot side portions.

Claims

1. A stator of an electrical machine, the stator comprising:

an elongate core defining an inner volume to receive a rotor of an electric machine; and

the core comprising a yoke and an array of teeth extending from the yoke toward the inner volume, the array of teeth defining slots between each pair of adjacent teeth in the array, each slot comprising;

a first slot region adapted to hold at least a portion of a conductive winding and defined by two non-parallel opposing slot side portions, and

a second slot region adapted to hold at least a portion of a conductive winding and defined by two parallel opposing slot side portions.

2. The stator of claim 1, each tooth comprising:

a first tooth portion having a uniform width along a radial length of the first tooth portion; and

a second tooth portion having a non-uniform width along a radial length of the second tooth portion.

3. The stator of claim 1, wherein the two non-parallel opposing slot side portions include a first slot side portion and a second slot side portion, the two parallel opposing slot side portions include a third slot side portion and a fourth slot side portion, the first slot side portion and the third slot side portion define a first slot side angle and form at least part of a first slot side, and the second slot side portion and the fourth slot side portion define a second slot side angle and form at least part of a second slot side, the first slot side angle unequal to the second slot side angle.

4. The stator of claim 1, wherein the first slot region of each slot resides between the yoke and the second slot region of each slot.

5. The stator of claim 1, wherein the second slot region of each slot resides between the yoke and the first slot region of each slot.

6. The stator of claim 1, further comprising a plurality of conductive coils residing in the slots, a first subset of the coils having a substantially circular cross-sectional profile and a second subset of the coils having a substantially rectangular cross-sectional profile.

7. The stator of claim 6, wherein the first subset of coils reside in the first slot region of each slot and the second subset of coils reside in the second slot region of each slot.

8. The stator of claim 1, wherein each slot comprises two interior corners and each interior corner defines a substantially right angle at an intersection of the yoke and one of the teeth.

9. The stator of claim 1, wherein each slot comprises two interior corners and each interior corner defines a corner radius at an intersection of the yoke and one of the teeth.

10. The stator of claim 9, further comprising a plurality of conductive coils residing in the slots, wherein the coils have a substantially circular cross-section, and a radius of the circular cross-section is substantially equal to the corner radius.

11. The stator of claim 1, further comprising a plurality of conductive coils residing in the slots, a first subset of the conductive coils comprising formed windings, a second subset of the coils comprising random-wound windings.

12. The stator of claim 1, further comprising a plurality of conductive coils residing in the slots and a plurality of wedges residing in the slots, wherein each wedge resides in contact with one or more of the coils.

13. The stator of claim 12, wherein each wedge exerts a force on one or more of the coils to reduce mobility of the coils within the slot.

14. The stator of claim 12, wherein each wedge defines an open volume in the slot, and the open volume is in fluid communication with the inner volume of the stator to allow cooling fluid to flow between the open volume and the inner volume.

15. The stator of claim 12, wherein each wedge contacts at least one of the teeth to define a wedge volume in the slot where the wedge resides and each wedge defines a plurality of apertures that allow fluid communication between the wedge volume and a region of the slot where one or more of the coils reside.

16. An electrical machine comprising:

a stator comprising an elongate core to internally receive a rotor of an electric machine; and

the core comprising a yoke and an array of teeth extending from the yoke, the core defining slots between neighboring teeth in the array, each slot having a depth defined by the yoke and one pair of neighboring teeth, each slot having a non-uniform width along a first portion of the depth of the slot, each slot having a uniform width along a second portion of the depth of the slot.

17. The electric machine of claim 16, wherein a shortest distance from the yoke of the stator to a radial end of each tooth defines a length of the tooth, each tooth comprises two sides that are parallel to each other along a first portion of the length of the tooth, and the two sides are non-parallel to each other along a second portion of the length of the tooth.

18. The electric machine of claim 17, each tooth further comprising a tooth tip that includes the radial end of the tooth, each tooth tip broader than a portion of the tooth adjacent the tooth tip.

19. The electric machine of claim 17, each tooth further comprising a tooth tip that includes the radial end of the tooth, each tooth tip including a tooth tip slot adapted to hold at least a portion of a wedge.

20. The electric machine of claim 16, further comprising conductive coils residing in each of the slots, wherein the coils each include one or more turns of conductive material, and an odd number of turns reside in at least one of the slots.

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

forming a core of the stator, the core defining an inner volume to receive a rotor of an electric machine;

the core comprising a yoke and an array of teeth extending from the yoke toward the inner volume, the array of teeth defining slots between each pair of adjacent teeth in the array, each slot comprising;

a first slot region adapted to hold at least a portion of a conductive winding and defined by two non-parallel opposing slot side portions, and

a second slot region adapted to hold at least a portion of a conductive winding and defined by two parallel opposing slot side portions.

22. The method of claim 21, wherein the two non-parallel opposing slot side portions include a first slot side portion and a second slot side portion, the two parallel opposing slot side portions include a third slot side portion and a fourth slot side portion, the first slot side portion and the third slot side portion define a first slot side angle and form at least part of a first slot side, and the second slot side portion and the fourth slot side portion define a second slot side angle and form at least part of a second slot side, the first slot side angle unequal to the second slot side angle.

23. The method of claim 21, further comprising installing a plurality of conductive coils in the slots.

24. The method of claim 23, wherein installing the plurality of conductive coils in the slots comprises:

forming a winding structure outside of the core and installing the formed winding structure in the second slot regions, the formed winding structure comprising a first subset of the coils; and

installing a second subset of the coils by successively forming individual turns of the coils in the first slot regions of the slots.

25. The method of claim 23, wherein installing the plurality of conductive coils in the slots comprises:

installing a first subset of the coils in the first slot regions, the first subset of the coils comprising a substantially circular cross-section; and

installing a second subset of the coils in the second slot regions of the slots, the second subset of the coils comprising a substantially rectangular cross-section.

26. The method of claim 23, further comprising installing a wedge in each slot.

27. The method of claim 26, further comprising receiving cooling fluid from the inner volume into the slots through apertures defined in each wedge.

28. The method of claim 21, further comprising operating the electric machine as a multi-pole electric machine.