Multi-layered platelet structure

• US 20070141324A1
• Filed: 01/23/2007
• Published: 06/21/2007
• Est. Priority Date: 04/15/2005
• Status: Active Grant

• Current Assignee: Siemens Energy Incorporated (Siemens AG)
• Original Assignee: Siemens Power Generation, Inc.
• Inventors: Stevens, Gary, Wood, John, Groeppel, Peter, B. Smith, James
• Granted Patent: US 7,846,853 B2
• Time in Patent Office: Days
• US Class Current: 428/324
• CPC Class Codes: H01B 3/025 Other inorganic material
• CPC Class Codes: H01B 3/04 mica
• CPC Class Codes: Y10T 428/24994 Fiber embedded in or on the surface of a polymeric matrix
• CPC Class Codes: Y10T 428/251 Mica
• CPC Class Codes: Y10T 428/2911 Mica flake
• CPC Class Codes: Y10T 442/2418 Coating or impregnation increases electrical conductivity or anti-static quality
• CPC Class Codes: Y10T 442/2475 Coating or impregnation is electrical insulation-providing, -improving, or -increasing, or conductivity-reducing
• CPC Class Codes: Y10T 442/2992 Coated or impregnated glass fiber fabric
• CPC Class Codes: Y10T 442/699 Including particulate material other than strand or fiber material

Abstract

An electrical insulation paper that is made of mica flakelets (22), having an average size range of 0.01 to 0.05 mm in their thinnest dimension, hexagonal boron nitride (26), which has an average size range of 10 to 1,000 nm in their longest dimension, and a resin matrix. The mica flakelets and the hexagonal boron nitride are mixed and formed into a paper (17), and the resin is added to the paper after formation, the ratio by weight of the hexagonal boron nitride to the mica flakelets is directly proportional to the average size of the hexagonal boron nitride compared to the average size of the mica flakelets, within an adjustment factor.

Claims

1. An electrical insulation component comprising:

mica flakelets, wherein said mica flakelets have an average size range of 0.01 to 0.05 mm in their thinnest dimension;

hexagonal boron nitride, wherein said hexagonal boron nitride has an average size range of 10 to 10,000 nm in their longest dimension; and

a resin matrix;

wherein said mica flakelets and said hexagonal boron nitride are mixed;

wherein the ratio by weight of said hexagonal boron nitride to said mica flakelets is directly proportional to the average size of said hexagonal boron nitride compared to the average size of said mica flakelets, within an adjustment factor of 0.5 to 2;

wherein the ratio by weight of said hexagonal boron nitride to said mica flakelets is never greater than approximately 1;

1 by weight.

2. The electrical insulation of claim 1, further comprising high thermal conductivity fillers.

3. The electrical insulation of claim 2, wherein said high thermal conductivity fillers comprises at least one of silica, alumina, magnesium oxide, silicon carbide, boron nitride, aluminum nitride, aluminum oxide, zinc oxide, titanium oxide and diamonds and dendrimers of approximately 1-1000 nm in size, and wherein said high thermal conductivity materials have aspect ratios of 10-50.

4. The electrical insulation of claim 2, wherein said high thermal conductivity fillers are loaded into said resin, and wherein said high thermal conductivity material comprises 25-40% by volume of said resin.

5. The electrical insulation of claim 1, wherein said mica flakelets and said hexagonal boron nitride are formed into a paper

6. The electrical insulation of claim 5, wherein said resin is impregnated into said mica flakelets and said hexagonal boron nitride after said paper is formed.

7. The electrical insulation of claim 1, wherein said mica flakelets and said hexagonal boron nitride are mixed with said resin to form a putty.

8. The electrical insulation of claim 1, wherein the hexagonal boron nitride has an average size range of 10-100 nm, and wherein the ratio of hexagonal boron nitride to mica is between 1:

1.00 and 1;

20 by weight.

9. The electrical insulation of claim 1, wherein the hexagonal boron nitride has an average size range of 100-1000 nm, and wherein the ratio of hexagonal boron nitride to mica is between 1:

50 and 1;

10 by weight.

10. The electrical insulation of claim 1, wherein the hexagonal boron nitride has an average size range of and 1000 nm to 10,000 nm, and wherein the ratio of hexagonal boron nitride to mica is between 1:

10 and 1;

2 by weight.

12. The electrical insulation paper of claim 1, further comprising high thermal conductivity fillers.

11. An electrical insulation paper comprising:

mica flakelets, wherein said mica flakelets have an average size range of 0.01 to 0.05 mm in their thinnest dimension;

hexagonal boron nitride, wherein said hexagonal boron nitride has an average size range of 10 to 1,000 nm in their longest dimension; and

a resin matrix;

wherein said mica flakelets and said hexagonal boron nitride are mixed and formed into a paper, and wherein said resin is added to said paper after formation;

wherein the ratio by weight of said hexagonal boron nitride to said mica flakelets is directly proportional to the average size of said hexagonal boron nitride compared to the average size of said mica flakelets, within an adjustment factor of 0.5 to 2;

wherein the ratio by weight of said hexagonal boron nitride to said mica flakelets is never greater than approximately 1;

1 by weight.

13. An electrical insulation composite comprising:

a mixture of platelet boron nitride and mica flakelets, wherein the ratio of said platelet boron nitride to said mica flakelets is directly proportional to the average size ranges within a factor of 0.5 to 2;

wherein said hexagonal boron nitride has an average size range of 10 to 10,000 nm in their longest dimension;

wherein said electrical insulation composite is combined with a resin matrix.

14. The electrical insulation composite of claim 13, wherein said platelet boron nitride is hexagonal boron nitride.

15. The electrical insulation composite of claim 13, wherein said boron nitride has an average size range of 1000 nm to 10,000 nm, and the factor is greater than 1.

16. The electrical insulation composite of claim 13, wherein said mica flakelets have an average size range of 1000 nm to 10,000 nm and of said platelet boron nitride to said mica flakelets is approximately 1:

1

17. The electrical insulation composite of claim 16, wherein said resin forms a paste with said composite.