Inductive wireless power transfer device with improved coupling factor and high voltage isolation

• US 10,700,551 B2
• Filed: 05/21/2018
• Issued: 06/30/2020
• Est. Priority Date: 05/21/2018
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Jacobson, Boris S., Volfson, Lev, Makowiec, Sara Lorene
• Primary Examiner(s): Borroto, Alfonso Perez
• Application Number:
  US15/984,596
• Publication Number:
  US 20190356165A1
• Time in Patent Office: 771 Days
• Field of Search: 307104
• CPC Class Codes: H01F 27/288 Shielding
• CPC Class Codes: H01F 27/324 Insulation between coil and core, between different winding sections, around the coil; Other insulation structures
• CPC Class Codes: H01F 27/36 Electric or magnetic shields or screens movable for varying inductance H01F21/10
• CPC Class Codes: H01F 27/363 made of electrically conductive material
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

An inductive wireless power transfer device includes a primary winding assembly and a secondary winding assembly separated from the primary winding assembly by a distance. A first magnetic core cap is on the primary winding assembly and a second magnetic core cap is on the secondary winding assembly so as to magnetically couple together the primary winding assembly and the secondary winding assembly. A multi-section high voltage (HV) isolator is interposed between the primary winding assembly and the secondary winding assembly. The multi-section HV isolator includes at least one individual insulator section comprising a dielectric material, and at least one intermediate magnetic core comprising a ferrite material interposed between the primary winding assembly and the secondary winding assembly.

Claims

1. An inductive wireless power transfer device comprises:

a primary winding assembly and a secondary winding assembly separated from the primary winding assembly by a distance;

a first magnetic core cap on the primary winding assembly and a second magnetic core cap on the secondary winding assembly so as to magnetically couple together the primary winding assembly and the secondary winding assembly; and

a multi-section high voltage (HV) isolator interposed between the primary winding assembly and the secondary winding assembly, the multi-section HV isolator including at least one individual insulator section comprising a dielectric material, and at least one intermediate magnetic core comprising a ferrite material interposed between the primary winding assembly and the secondary winding assembly,

wherein the multi-section HV isolator includes a core isolator portion extending along a first axis between a first core isolator portion and an opposing second core isolator portion to define a core isolator height, and an outer isolator surface extending along a second axis perpendicular to the first axis to define an isolator width, and

wherein the at least one intermediate magnetic core includes a middle non-sectioned ferrite core embedded in the core isolator portion, the middle section ferrite core extending along the first axis to define a ferrite core height, and extending along the second axis to define a ferrite core width that is less than the ferrite core height.

2. The inductive wireless power transfer device of claim 1, wherein the at least one individual insulator section includes a plurality of insulator sections extending radially from the core isolator portion.

3. The inductive wireless power transfer device of claim 2, wherein each individual insulator section has a disc shape, the individual insulator sections being separated from one another by a void.

4. The inductive wireless power transfer device of claim 3, wherein the disc-shaped insulator sections include an exterior disc sidewall extending parallel with the vertical axis between a first disc surface and an opposing second disc surface to define an insulator height.

5. The inductive wireless power transfer device of claim 4, wherein the middle non-sectioned ferrite core extends through the center of each disc-shaped insulator section.

6. The inductive wireless power transfer device of claim 1, wherein the at least one intermediate magnetic core includes a first individual core layer and a second individual core layer spaced apart from the first individual core layer along the first axis.

7. The inductive wireless power transfer device of claim 6, wherein the first and second individual core layers extend radially from the first axis to define a layer width, and include an exterior sidewall extending parallel with the vertical axis between a first layer surface and an opposing second layer surface to define a layer thickness that is less than the layer width.

8. The inductive wireless power transfer device of claim 7, wherein multi-section HV isolator includes a first intermediate insulator layer interposed between the first and second individual core layers.

9. The inductive wireless power transfer device of claim 8, wherein the first individual core layer is directly on a first surface of the first intermediate insulator layer, and the second individual core layer is on an opposing second surface of the first intermediate insulator layer.

10. The inductive wireless power transfer device of claim 8, wherein multi-section HV isolator further includes a second intermediate insulator layer interposed between the first individual core layer and the primary winding assembly, and a third intermediate insulator layer interposed between the second individual core layer and the secondary winding assembly.

11. The inductive wireless power transfer device of claim 10, wherein the primary winding assembly includes a primary winding interposed between a first insulator cap layer and a primary winding insulator layer.

12. The inductive wireless power transfer device of claim 11, wherein the primary winding assembly further includes a primary shield interposed between the first magnetic core cap and the multi-section HV isolator, and wherein the primary winding and the primary winding insulator layer are disposed within the primary shield.

13. The inductive wireless power transfer device of claim 12, wherein the secondary winding assembly includes a secondary winding interposed between a second insulator cap layer and a secondary winding insulator layer.

14. The inductive wireless power transfer device of claim 13, wherein the secondary winding assembly further includes a secondary shield interposed between the second magnetic core cap and the multi-section HV isolator, and wherein the secondary winding and the secondary winding insulator layer are disposed within the secondary shield.

15. A method of increasing power transfer in an inductive wireless power transfer device, the method comprising:

separating a primary winding assembly from a secondary winding assembly by a distance;

arranging a first magnetic core cap on the primary winding assembly and arranging a second magnetic core cap on the secondary winding assembly so as to magnetically couple together the primary winding assembly and the secondary winding assembly; and

interposing a multi-section high-voltage (HV) isolator between the primary winding assembly and the secondary winding assembly so as to increase the coupling between the primary winding assembly and the secondary winding assembly, the multi-section HV isolator including at least one individual insulator section comprising a dielectric material, and at least one intermediate magnetic core comprising a ferrite material interposed between the primary winding assembly and the secondary winding assembly,

wherein the multi-section HV isolator includes a core isolator portion extending along a first axis between a first core isolator portion and an opposing second core isolator portion to define a core isolator height, and an outer isolator surface extending along a second axis perpendicular to the first axis to define an isolator width, and

wherein the at least one intermediate magnetic core includes a middle non-sectioned ferrite core embedded in the core isolator portion, the middle section ferrite core extending along the first axis to define a ferrite core height, and extending along the second axis to define a ferrite core width that is less than the ferrite core height.

16. The method of claim 15, wherein a first individual core layer and a second individual core layer are spaced apart from the first individual core layer along the first axis.