Rotor end-bell for electric generators

Patent metadata

Field	Value
Publication number	US-9859766-B2
Application number	US-201214128276-A
Country	US
Kind code	B2
Filing date	Jun 13, 2012
Priority date	Jun 21, 2011
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A rotor end-bell ( 2 ) for an electric generator, the rotor end-bell ( 2 ) being made at least in part of fiber-reinforced plastic. A rotor ( 1 ) and an electric generator (T) have at least one such rotor end-bell ( 2 ). The end-bell can be advantageously used in high-speed turbo generators.

First claim

The invention claimed is:

1. A rotor end-bell configured for placement on an end of a rotor of an electric generator, wherein the rotor end-bell is at least partially comprised of fiber reinforced plastic, a portion of the rotor end-bell comprising fiber reinforced plastic being configured to surround and directly contact an end winding of the rotor, the portion of the rotor end-bell, which comprises fiber reinforced plastic, being configured to contact a portion of the radial thickness of the end winding of the rotor at an end of the end winding of the rotor,
wherein the rotor end-bell has a radially inner side, a spacer ring is configured and located to define a support surface between the rotor end-bell and a support for the rotor end-bell, the spacer ring has a single step to allow an outer side of the spacer ring to bear against an inner side of the portion of the rotor end-bell comprising fiber reinforced plastic, the single step of the spacer ring bearing against a double step of the inner side of the portion of the rotor end-bell comprising fiber reinforced plastic.

2. The rotor end-bell as claimed in claim 1 , wherein the plastic includes fibers that have at least one preferred direction in the end-bell which at least substantially comprises a circumferential direction of the rotor end-bell.

3. The rotor end-bell as claimed in claim 1 , wherein the plastic includes fibers and the fibers include carbon fibers.

4. The rotor end-bell as claimed in claim 1 , wherein the plastic includes fibers and the fibers include ceramic fibers.

5. The rotor end-bell as claimed in claim 4 , wherein the ceramic fibers are aluminum oxide fibers.

6. The rotor end-bell as claimed in claim 1 , wherein the plastic includes fibers and the fibers include boron fibers.

7. The rotor end-bell as claimed in claim 1 , wherein the plastic includes fibers that are embedded in a matrix comprising a resin.

8. The rotor-end bell as claimed in claim 7 , wherein the matrix comprises epoxy resin.

9. The rotor end-bell as claimed in claim 1 , wherein the spacer ring has a lower specific electrical resistance than the fiber reinforced plastic material of which the rotor end-bell is comprised.

10. The rotor end-bell as claimed in claim 9 , wherein the inner side of the spacer ring has a thread.

11. The rotor-end bell as claimed in claim 10 , wherein the thread is a conical thread.

12. The rotor end-bell as claimed in claim 9 , wherein the spacer ring is comprised of copper or of steel having a low alloying contribution.

13. The rotor end-bell as claimed in claim 1 , wherein the rotor end-bell is configured for producing a quarter turn connection around the end of the rotor of the electric generator on which the rotor end-bell is placed.

14. A rotor for an electric generator having at least one rotor end-bell as claimed in claim 1 disposed on the end of the rotor.

15. The rotor as claimed in claim 14 , wherein the rotor end-bell has been installed on the end of the rotor by the end-bell being previously cooled and subsequently shrunk onto the end of the rotor.

16. An electric generator with at least one rotor as claimed in claim 14 .

17. The electric generator of claim 16 , wherein the electric generator is a turbo generator.

18. A rotor end-bell configured for placement on an end of a rotor of an electric generator, wherein
the rotor end-bell is at least partially comprised of fiber reinforced plastic;
the rotor end-bell has a radially inner side, a spacer ring configured and located to define a support surface between the rotor end-bell and a support for the end-bell,
the spacer ring has a lower specific electrical resistance than the fiber reinforced plastic material of which the rotor end-bell is comprised; and
the spacer ring has an outer side, which bears against the fiber reinforced plastic of the rotor end-bell, and an intensely conductive layer between the outer side of the spacer ring and the rotor end-bell.

19. The rotor-end bell as claimed in claim 18 , wherein the intensely conductive layer is silver.

20. A rotor of an electric generator including a rotor end-bell, the rotor end-bell being configured for placement on an end of the rotor, wherein
the rotor end-bell is at least partially comprised of fiber reinforced plastic;
the rotor end-bell has a radially inner side, a spacer ring configured and located to define a support surface between the rotor end-bell and a support for the end-bell,
the spacer ring has a lower specific electrical resistance than the fiber reinforced plastic material of which the rotor end-bell is comprised;
the inner side of the spacer ring has a thread; and
a mating thread, matching the thread of the spacer ring, is located on support surfaces of teeth of the rotor.

Assignees

• Gröppel Peter
• Lang Steffen
• Rohr Claus
• Siemens Ag

Inventors

• Gröppel Peter
• Lang Steffen
• Rohr Claus

Classifications

• H02K3/51 Primary

  applicable to rotors only · CPC title

• H02K5/02

  Casings or enclosures characterised by the material thereof · CPC title

• H02K3/527

  applicable to rotors only · CPC title