Optimization of transmit and transmit/receive (TRX) coils for wireless transfer of power

Patent metadata

Field	Value
Publication number	US-10784044-B2
Application number	US-201916376955-A
Country	US
Kind code	B2
Filing date	Apr 5, 2019
Priority date	Apr 30, 2018
Publication date	Sep 22, 2020
Grant date	Sep 22, 2020

Abstract

In accordance with embodiments of the present invention, a coil design for the transmission of wireless power. In some embodiments, the coil can include a winding with one or more turns of conductive traces mounted on a substrate, wherein the one or more turns include characteristics that enhance operation of the coil. In some embodiments, the winding includes a transmit coil and a receive coil, each coupled to terminals that provide for a transmit functionality and a receive functionality. In some embodiments, the traces are varied in width and/or thickness in order to optimize the inductance and the coil resistance. In some embodiments, parameters of a control circuit coupled to the coil to affect a transmit functionality or a receive functionality can be optimized.

First claim

What is claimed is:

1. A coil for wireless power transmission, comprising:
a winding comprising a plurality of turns of conductive traces mounted on a substrate, the plurality of turns of the winding being configurable to form a receive coil and a transmit coil,
wherein the plurality of turns varies the width of the conductive traces to enhance operation of the coil,
wherein each of the plurality of turns is formed of a plurality of fingers, the plurality of fingers in the plurality of turns is varied in width and/or number of fingers across the winding,
wherein the plurality of turns is separated into outer turns and inner turns, each of which is formed to top traces and bottom traces formed on opposite sides of the substrate, the top traces and bottom traces of the outer turns being coupled together in parallel, and the top traces and bottom traces of the inner turns being coupled in series together and in series with the parallel coupled traces of the outer turns.

2. The coil of claim 1 , wherein the plurality of turns of the winding are coupled to a plurality of terminals, wherein the plurality of turns are arranged with the plurality of terminals such that a transmit coil is formed between a first pair of the plurality of terminals and a receive coil is formed between a second set of the plurality of terminals.

3. The coil of claim 2 , wherein the plurality of terminals includes one of two, three, or four terminals.

4. The coil of claim 1 , wherein the plurality of turns is separated into outer turns and inner turns and wherein a space separates the outer turns and the inner turns, the outer turns being coupled to receive terminals to form the receive coil and the inner turns being coupled to transmit terminals to provide the transmit coil, the space being sufficient to accommodate communications coils positioned between the outer turns and the inner turns.

5. The coil of claim 1 , wherein unused portions of the substrate between the plurality of turns is partially filled with a conductor coupled to the turns to reduce coil resistance.

6. The coil of claim 1 , wherein the plurality of turns are separated into outer turns and inner turns formed within the outer turns, wherein the width of inner turns is less than the width of outer turns.

7. The coil of claim 1 , wherein the winding includes
an outer coil wherein traces of the outer coil increase in width from an inner trace to an outer trace, the outer coil being configured to form the receive coil; and
an inner coil wherein traces of the inner coil have less width than that of the outer coil, the inner coil being configured to form the transmit coil.

8. The coil of claim 7 , wherein the width of traces forming the one or more turns is varied stepwise across the plurality of turns.

9. The coil of claim 7 , wherein the width of traces forming the plurality of turns is varied continuously across the winding.

10. The coil of claim 7 , wherein the trace widths of the transmit coil and the receive coil each include two or more distinct widths.

11. The coil of claim 1 , wherein the plurality of fingers vary in the width of the fingers in each turn.

12. The coil of claim 1 , wherein the plurality of fingers vary in the number of fingers in each turn.

13. The coil of claim 12 , wherein the number of fingers is greater in outer turns of the plurality of turns than it is in inner turns of the plurality of turns.

14. The coil of claim 1 , wherein the substrate includes a ferrite core and wherein the plurality of turns are thinner on inner turns of the winding and thicker on outer turns of the winding, the ferrite core on which the coil is mounted being thicker under the inner turns of the winding and thinner under the outer turns of the winding.

15. The coil of claim 1 , wherein the coil is electronically coupled to a control circuit, the control circuit comprising:
a transmit circuit coupled to drive the plurality of turns configured to form the transmit coil in a transmit functionality;
a receive circuit coupled to the plurality of turns configured to form the receive coil in a receive functionality; and
a controller that determines between a transmit mode and a receive mode and, in transmit mode, activates the transmit circuit and, in receive mode, activates the receive circuit.

16. The coil of claim 15 , wherein the transmit circuit includes
a transmit driver; and
transmit capacitors coupled to the transmit driver.

17. The coil of claim 16 , wherein the transmit circuit and the receive circuit share one or more capacitors.

18. The coil of claim 16 , wherein one or more of a transmit operating frequency, an on-the-go voltage, and a deadtime is adjusted for efficiency.

Assignees

• Integrated Device Tech

Inventors

• Qi Tao
• Mehas Gustavo
• Jeong Chan Young
• Gu Xinyun
• Smith Nicholaus Wayne
• Bavisi Amit D
• Sugasawara Daryl Jay
• Lee Aihua
• Kan Tianze

Classifications

• H01F27/366

  made of ferromagnetic material · CPC title

• H02J50/10

  using inductive coupling · CPC title

• H01F38/14 Primary

  Inductive couplings {(for wireless supply or distribution of electric power using inductive coupling H02J50/10)} · CPC title

• H01F27/29

  Terminals; Tapping arrangements {for signal inductances} · CPC title

• H01F27/006

  with special arrangement or spacing of turns of the winding(s), e.g. to produce desired self-resonance · CPC title