System and method for reducing partial discharge in high voltage planar transformers

Patent metadata

Field	Value
Publication number	US-9620278-B2
Application number	US-201414184632-A
Country	US
Kind code	B2
Filing date	Feb 19, 2014
Priority date	Feb 19, 2014
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

A device includes a printed circuit board (PCB). The device may also include a high voltage coil disposed on the PCB and a low voltage coil disposed on the PCB. Further, a conductive shield forms a three-dimensional enclosure around the high voltage coil and confines an electric field generated by the device to the PCB.

First claim

The invention claimed is:

1. A device comprising:
a printed circuit board (PCB);
a high voltage coil comprising first traces disposed on the PCB;
a low voltage coil comprising second traces disposed on the PCB as one or more windings; and
a conductive shield comprising a three-dimensional enclosure around the high voltage coil, wherein the conductive shield is configured to be driven at a same potential as the low voltage coil or the one or more windings of the low voltage coil comprise the conductive shield, wherein the three-dimensional enclosure comprises third traces, wherein the conductive shield confines an electric field generated by the device to the PCB.

2. The device of claim 1 , wherein a magnetic core is coupled to the PCB.

3. The device of claim 2 , wherein the magnetic core and one or more sides of the conductive shield are separated by an air gap.

4. The device of claim 2 , wherein the magnetic core is disposed within an aperture formed in the PCB.

5. The device of claim 1 , wherein the PCB is a multi-layered PCB.

6. The device of claim 5 , wherein the high voltage coil is disposed in at least an internal layer of the PCB.

7. The device of claim 6 , wherein the internal layer has a first thickness, a first exposed layer of the PCB and a second exposed layer of the PCB have a second thickness, and the first thickness is greater than the second thickness.

8. The device of claim 5 , wherein the low voltage coil is disposed in at least one layer above or below a layer of the PCB containing the high voltage coil.

9. The device of claim 1 , wherein the conductive shield comprises a slit, wherein the slit prevents shorting.

10. The device of claim 1 , wherein the conductive shield comprises a top layer disposed on a first exposed layer of the PCB and a bottom layer disposed on a second exposed layer of the PCB.

11. The device of claim 10 , wherein at least one of the top or bottom layer comprises the one or more windings of the low voltage coil.

12. A system comprising:
a first printed circuit board (PCB) comprising circuitry; and
a second PCB comprising a planar transformer coupled to the circuitry that interacts with the first PCB, wherein the planar transformer comprises:
a magnetic core coupled to the second PCB;
a high voltage coil comprising first traces disposed on the second PCB adjacent to the magnetic core;
a low voltage coil comprising second traces disposed on the second PCB adjacent to the magnetic core; and
a conductive shield comprising a three-dimensional enclosure around the high voltage coil, wherein the conductive shield is configured to be driven at a same potential as the low voltage coil or the low voltage coil comprises the conductive shield, wherein the three-dimensional enclosure comprises third traces, wherein the conductive shield confines an electric field generated by the planar transformer to the second PCB.

13. The system of claim 12 , wherein the magnetic core is disposed within an aperture formed in the second PCB.

14. The system of claim 13 , wherein the magnetic core comprises a top section and a bottom section, and wherein top and bottom sections are disposed within the aperture and are secured together with a fastener.

15. The system of claim 12 , wherein the second PCB comprises a multi-layered PCB.

16. The system of claim 15 , wherein the high voltage coil is disposed on at least an internal layer of the PCB.

17. The system of claim 12 , wherein the second PCB is a board-mounted component disposed on the first PCB.

18. A method for manufacturing a device, comprising:
disposing a high voltage coil comprising first traces on a printed circuit board (PCB);
disposing a low voltage coil comprising second traces on the PCB; and
disposing a conductive shield on the PCB, wherein the conductive shield comprises a three-dimensional enclosure comprising third traces around the high voltage coil, wherein the conductive shield is configured to be driven at a same potential as the low voltage coil or the low voltage coil comprises the conductive shield, and wherein the conductive shield confines an electric field generated by the device within the PCB.

19. The method of claim 18 , wherein the method further comprises coupling a magnetic core to the PCB.

20. The method of claim 18 , wherein the method further comprises applying a silkscreen marking to the PCB.

Assignees

• Gen Electric

Inventors

• Lovell Alan Carroll
• Shepard Mark Eugene
• Mcarthur Andrew David
• Chen Qin
• Greenleaf Todd David

Classifications

• H05K2201/098

  Special shape of the cross-section of conductors, e.g. very thick plated conductors · CPC title

• H05K1/0254

  High voltage adaptations; Electrical insulation details; Overvoltage or electrostatic discharge protection (electrostatic discharge protection for electric apparatus in general H05K9/0067, H05K9/0079); Arrangements for regulating voltages or for using plural voltages · CPC title

• H01F2027/2819

  Planar transformers with printed windings, e.g. surrounded by two cores and to be mounted on printed circuit · CPC title

• H01F2027/2809

  on stacked layers · CPC title

• H05K2201/09672

  Superposed layout, i.e. in different planes · CPC title