Generator rotor with coil end-turn retention mechanism

Patent metadata

Field	Value
Publication number	US-11038394-B2
Application number	US-201815879639-A
Country	US
Kind code	B2
Filing date	Jan 25, 2018
Priority date	Jan 25, 2018
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

A rotor assembly includes a rotor core having winding slots, and one or more coils, which have slot-inserted segments included in the winding slots, and first and second end-turn segments external to the winding slots and located around opposite axial ends of the rotor core, respectively. The rotor assembly further includes a first containment band located around at least a portion of the first end-turn segments and configured to prevent the first end-turn segments from moving away from the rotor core radially, a second containment band located around at least a portion of the second end-turn segments and configured to prevent the second end-turn segments from moving away from the rotor core radially, and one or more sticks mounted in one or more of the winding slots, respectively. The first and second containment bands are retained via the sticks against moving away axially.

First claim

The invention claimed is:

1. A rotor assembly for a generator, comprising: a rotor core having a plurality of winding slots arranged in a circumferential direction of the rotor core;
one or more coils, comprising (i) a plurality of slot-inserted segments, each slot-inserted segment being inserted between two winding slots of the plurality of winding slots; and (iii) first and second end-turn segments external to the winding slots and located around opposite axial ends of the rotor core, respectively;
a first containment band comprising a first-band catch and being located around at least a portion of the first end-turn segments and configured to prevent the first end-turn segments from moving away from the rotor core radially;
a second containment band comprising a second-band catch and being located around at least a portion of the second end- turn segments and configured to prevent the second end-turn segments from moving away from the rotor core radially; and
one or more sticks (i) comprising a first stick-catch and a second stick-catch respectively formed at opposite ends thereof; (ii) being inserted between two winding slots of the plurality of winding slots; and (ii) arranged above a slot-inserted segment of the plurality of slot-inserted segments;
wherein via a snap-fit mechanism, the first band-catch is locked to the first stick catch, and the second band-catch is locked to the second stick-catch, such that the first and second containment bands are retained via the sticks against moving away axially.

2. The rotor assembly of claim 1 , wherein the first and second containment bands are connected to the sticks via a snap fit mechanism.

3. The rotor assembly of claim 1 , wherein the stick-catches comprise an upward hook, and the band-catches comprise a downward hook.

4. The rotor assembly of claim 1 , wherein:
the first containment band comprises a core-adjacent end adjacent to one of the opposite axial ends of the rotor core, and the first band-catch is formed around the core- adjacent end of the first containment band; and
the second containment band comprises a core-adjacent end adjacent to the other of the opposite axial ends of the rotor core, and the second band-catch is formed around the core- adjacent end of the second containment band.

5. The rotor assembly of claim 1 , wherein the first containment band radially encloses therein the at least a portion of the first end-turn segments, and the second containment band radially encloses therein the at least a portion of the second end-turn segments.

6. The rotor assembly of claim 1 , wherein an axial gap is defined between the rotor core and at least one of the first and second containment bands, and the axial gap is configured to allow cooling fluid for cooling the coils to exit radially.

7. A generator, comprising:
a stator; and
a rotor assembly rotationally mounted at least partially within the stator, the rotor assembly comprising:
rotor core having a plurality of winding slots arranged in a circumferential direction of the rotor core;
one or more coils, comprising (i) a plurality of slot-inserted segments, each slot-inserted segment being inserted between two winding slots of the plurality of winding slots; and (ii) first and second end-turn segments external to the winding slots and located around opposite axial ends of the rotor core, respectively;
a first containment band comprising a first-band catch and being located around at least a portion of the first end- turn segments and configured to prevent the first end-turn segments from moving away from the rotor core radially;
a second containment band comprising a second-band catch and being located around at least a portion of the second end-turn segments and configured to prevent the second end-turn segments from moving away from the rotor core radially; and
one or more sticks (i) comprising a first stick-catch and a second stick-catch respectively formed at opposite ends thereof; (ii) being inserted between two winding slots of the plurality of winding slots; and (ii) arranged above a slot-inserted segment of the plurality of slot-inserted segments.
wherein via a snap-fit mechanism, the first band-catch is locked to the first stick catch, and the second band-catch is locked to the second stick-catch, such that the first and second containment bands are retained via the sticks against moving away axially.

8. The generator of claim 7 , wherein the first and second containment bands are connected to the sticks via a snap fit mechanism.

9. The generator of claim 7 , wherein:
the sticks comprise a first stick-catch and a second stick-catch respectively formed at opposite ends thereof;
the first containment band comprises a first band-catch for engaging the first stick-catch in a snap fit manner; and
the second containment band comprises a second band-catch for engaging the second stick-catch in a snap fit manner.

10. The generator of claim 9 , wherein the stick-catches comprise an upward hook, and the band-catches comprise a downward hook.

11. The generator of claim 9 , wherein:
the first containment band comprises a core-adjacent end adjacent to one of the opposite axial ends of the rotor core, and the first band-catch is formed around the core- adjacent end of the first containment band; and
the second containment band comprises a core-adjacent end adjacent to the other of the opposite axial ends of the rotor core, and the second band-catch is formed around the core- adjacent end of the second containment band.

12. The generator of claim 7 , wherein the first containment band radially encloses therein the at least a portion of the first end-turn segments, and the second containment band radially encloses therein the at least a portion of the second end-turn segments.

13. The generator of claim 7 , further comprising a hollowed rotation shaft, on which the rotor core is mounted, wherein radial holes defined through the thickness of the rotation shaft and at least one axial gap defined between the rotor core and at least one of the first and second containment bands are configured to allow cooling fluid to come out from the rotation shaft, impinge and cool the first and second end-turn segments of the coils, and exit radially from the rotor assembly.

14. A method of assembling a rotor, comprising:
providing a rotor core having a plurality of winding slots arranged in a circumferential direction of the rotor core;
winding one or more coils on the rotor core, with a plurality of slot-inserted segments of the coils, each slot-inserted segment being inserted between two winding slots of the plurality of winding slots; and first and second end-turn segments of the coils external to the winding slots and located around opposite axial ends of the rotor core, respectively;
disposing a first containment band comprising a first-band catch around at least a portion of the first end-turn segments to prevent the first end-turn segments from moving away from the rotor core radially;
connecting one or more sticks comprising a first stick-catch and a second stick-catch respectively formed at opposite ends thereof, to the first containment band, by inserting the one or more sticks between two winding slots of the plurality of winding slots and arranging the one or more sticks above a slot-inserted segment of the plurality of slot-inserted segments;
axially pushing the sticks into the first containment band and snap-fitting the sticks onto the first containment band such that the first band catch is locked to the first stick catch;
disposing a second containment band comprising a second-band catch around at least a

Assignees

• Ge Aviation Systems Llc

Inventors

• Chhabra Parmeet Singh
• Yamarthi David Raju
• Soni Navin
• Ramakrishnaiah Mamatha
• Sridharan Balamurugan

Classifications

• H02K9/19

  for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil · CPC title

• H02K15/021

  Magnetic cores · CPC title

• H02K15/13

  Applying slot closure means in the cores; Manufacture of slot closure means · CPC title

• H02K1/32

  with channels or ducts for flow of cooling medium · CPC title

• H02K3/51 Primary

  applicable to rotors only · CPC title