Bolted spherical series and phase connector for stator coils of electrical generators

• US 7,400,072 B2
• Filed: 12/07/2005
• Issued: 07/15/2008
• Est. Priority Date: 12/10/2004
• Status: Expired due to Fees

• Current Assignee: Siemens Energy Incorporated (Siemens AG)
• Original Assignee: Siemens Power Generation, Inc.
• Inventors: Ward, Robert A.
• Primary Examiner(s): NGUYEN, TRAN N
• Application Number:
  US11/295,994
• Publication Number:
  US 20060125343A1
• Time in Patent Office: 951 Days
• Field of Search: 310/71, 310/260, 310/270, 439/798
• US Class Current: 310/71
• CPC Class Codes: H02K 3/505 for large machine windings, e.g. bar windings H02K3/51 takes precedence

Abstract

A connector arrangement and techniques are provided for reducing eddy current losses and/or skin effects while enabling more readily serviceable series and phase connections between the coil ends 12 and 18 of a generator stator 10. This may be achieved by providing a connecting structure 24 that enables two parallel electrically conductive paths 26 and 28 that are electrically insulated from one another for passing a respective flow of electric current between the coil ends.

Claims

1. An electrical generator comprising:

at least one pair of stator coil sections having spaced apart ends each having a header cap configured to define a spherical geometry, wherein each header cap comprises split header cap portions of a conductive material to provide at least two parallel paths for passing a respective flow of electric current;

an electrical insulating material interposed between said split header cap portions;

a connector for connecting said pair of coil sections at their ends through said header caps, wherein said connector is configured to maintain electrically insulated said at least two parallel paths for passing the respective flow of electric current, wherein said connector comprises at least two connecting bars of a conductive material;

an air gap interposed between said at least two connecting bars, wherein each of said bars includes two detents configured with a geometry complementary relative to the geometry of the header caps for tightly receiving said header caps; and

means for mechanically affixing said at least two connecting bars to one another while maintaining said air gap there between.

2. The electrical generator of claim 1, wherein said mechanical affixing means comprise a plurality of bolts of a conductive material, and wherein each bolt includes at least one insulating sleeve disposed over a respective bolt segment to prevent an electrical connection between the respective bolt segment and a corresponding portion of one of the connector bars.

3. The electrical generator of claim 1 wherein each header cap includes a conduit for passing a cooling fluid.

4. The electrical generator of claim 1 wherein each detent has a portion configured to accommodate circumferential and/or radial misalignment that may occur between said coil ends.