STATOR WINDING METHOD AND APPARATUS

• US 20090127966A1
• Filed: 09/05/2008
• Published: 05/21/2009
• Est. Priority Date: 11/15/2007
• Status: Active Grant

• Current Assignee: Sundyne, LLC
• Original Assignee: Gardner Denver Deutschland GmbH, Sundyne Corporation
• Inventors: Palko, Marko, Saari, Juha, Lantto, Erkki
• Granted Patent: US 7,876,016 B2
• Time in Patent Office: Days
• US Class Current: 310/213
• CPC Class Codes: H02K 15/085 by laying conductors into slotted stators
• CPC Class Codes: H02K 3/14 with transposed conductors, e.g. twisted conductors

Abstract

A stator assembly includes a stator core and at least one conductive bundle. The stator core has a first end, a second end, and a plurality of slots extending from the first end to the second end. The conductive bundle includes a plurality of individually insulated conductive wires. At least one portion of the at least one conductive bundle extends from the first end to the second end of one slot of the plurality of slots. The at least one portion is twisted by a predetermined amount within the one slot to minimize a circulatory current along the plurality of individual insulated conductive wires in the at least one portion.

Claims

1. A stator assembly, comprising:

a stator core having a first end, a second end, and a plurality of slots extending from the first end to the second end; and

at least one conductive bundle including a plurality of individually insulated conductive wires, wherein at least one portion of the at least one conductive bundle extends from the first end to the second end of one slot of the plurality of slots, and wherein the at least one portion is twisted by a predetermined amount within the one slot to minimize a circulatory current along the plurality of individual insulated conductive wires in the at least one portion.

2. The stator assembly of claim 1, wherein the at least one portion comprises a plurality of portions of the conductive bundle with each portion being inserted into one slot of the plurality of the slots to form a coil having a plurality of coil sections, each coil section having at least one turn.

3. The stator assembly of claim 2, wherein the plurality of portions comprises twelve portions of the conductive bundle that are placed in twelve different slots and are each twisted by the predetermined amount within each of the twelve slots to form a coil having six coil sections.

4. The stator assembly of claim 3, wherein each coil section includes at least one turn of the conductive bundle.

5. The stator assembly of claim 3, wherein each coil section includes two, three, or four turns of the conductive bundle.

6. The stator assembly of claim 1, wherein the predetermined amount is at least 360 degrees.

7. The stator assembly of claim 1, wherein the at least one conductive bundle corresponds to a single bundle of individual insulated conductive wires.

8. The stator assembly of claim 1, wherein the at least one conductive bundle includes a plurality of discrete bundles of individual insulated conductive wires, with each discrete bundle being individually twisted prior to the portion of the at least one conductive bundle being twisted by the predetermined amount.

9. The stator assembly of claim 1, wherein the stator core is cylindrical and wherein the slots extend along an inner peripheral surface of the stator core and are parallel to a central axis of the stator core.

10. The stator assembly of claim 1, wherein the at least one conductive bundle comprises a plurality of conductive bundles, each conductive bundle corresponding to a phase of alternating current produced by the stator assembly.

11. The stator assembly of claim 1, wherein the at least one conductive bundle comprises a plurality of pairs of conductive bundles, wherein each pair of conductive bundles corresponds to a phase of alternating current associated with the stator assembly, and wherein each pair of conductive bundles includes at least two conductive bundles connected in parallel.

12. The stator assembly of claim 1, wherein each of the plurality of individual insulated conductive wires has an enamel insulating coating.

13. The stator assembly of claim 1, wherein each of the plurality of slots includes a first slot portion that is closer to an outer peripheral surface of the stator core and a second slot portion that is closer to an inner peripheral surface of the stator core, wherein the at least one conductive bundle includes a first conductive bundle and a second conductive bundle, and wherein the one slot contains a portion of the first conductive bundle in the first slot portion and a portion of the second conductive bundle in the second slot portion separated by an insulating separation layer.

14. The stator assembly of claim 1, wherein the stator assembly is associated with an electric machine that is operable to produce a voltage having a range of 400-690 volts and to yield power having a range of 100-600 kilowatts, the electric machine having a rotor that rotates between 20,000-100,000 revolutions per minute.

15. A method of forming a stator assembly, comprising:

grouping a plurality of individual insulated conductive wires into a conductive bundle;

placing a portion of the conductive bundle in a stator core slot extending from a first end of a stator core to a second end of the stator core; and

twisting the bundle such that the portion is twisted by a predetermined amount within the stator core slot to minimize a circulatory current along the plurality of individual insulated conductive wires in the portion.

16. The method of claim 15, wherein said step of grouping a plurality of individual insulated conductive wires into a conductive bundle includes grouping the plurality of individual insulated conductive wires into a single bundle.

17. The method of claim 15, wherein said step of grouping a plurality of individual insulated conductive wires into a conductive bundle comprises:

twisting a first plurality of individual insulated conductive wires to form a first discrete conductive bundle;

twisting a second plurality of individual insulated conductive wires to form a second discrete conductive bundle;

twisting a third plurality of individual insulated conductive wires to form a third discrete conductive bundle; and

grouping the first discrete conductive bundle, the second discrete conductive bundle, and the third discrete conductive bundle together to provide a combined conductive bundle.

18. The method of claim 15, wherein said step of placing a portion of the conductive bundle in a stator core slot extending axially from a first end of a stator core to a second end of the stator core comprises:

a) inserting a first portion of the conductive bundle into a first stator core slot;

b) twisting the conductive bundle such that the first portion is twisted by the predetermined amount within the first stator core slot;

c) inserting a second portion of the conductive bundle into a second stator core slot; and

d) twisting the conductive bundle such that the second portion is twisted by the predetermined amount within the second stator core slot.

19. The method of claim 18, including selectively repeating steps (a)-(d) in the same stator core slots to form a coil having a desired quantity of turns.

20. The method of claim 18, including selectively repeating steps (a)-(d) in different stator core slots to form a coil having a desired quantity of coil sections.