Wireless power transmitter with a plurality of magnetic oscillators

Patent metadata

Field	Value
Publication number	US-2017194819-A1
Application number	US-201715464040-A
Country	US
Kind code	A1
Filing date	Mar 20, 2017
Priority date	Jul 3, 2013
Publication date	Jul 6, 2017
Grant date	—

Abstract

One aspect of the disclosure provides a power receiver configured to wirelessly transfer power from at least one power transmitter. The power receiver comprises a plurality of magnetic oscillators, each magnetic oscillator of the plurality of magnetic oscillators having a mechanical resonant frequency substantially equal to a first frequency, the plurality of magnetic oscillators configured to generate a first time-varying magnetic field in response to exposure to a second time-varying magnetic field. The power receiver further comprises at least one current circuit configured to generate a time-varying electric current in response to exposure to the first time-varying magnetic field. The first time-varying magnetic field has an operating frequency substantially equal to the first frequency.

First claim

What is claimed is:

1 . A power receiver configured to wirelessly receive power from at least one power transmitter, the power receiver comprising:
a plurality of magnetic oscillators, each magnetic oscillator of the plurality of magnetic oscillators having a mechanical resonant frequency substantially equal to a first frequency, the plurality of magnetic oscillators configured to generate a first time-varying magnetic field in response to exposure to a second time-varying magnetic field; and at least one current circuit configured to generate a time-varying electric current in response to exposure to the first time-varying magnetic field, the first time-varying magnetic field having an operating frequency substantially equal to the first frequency, wherein the plurality of magnetic oscillators comprises:
a first set of magnetic oscillators positioned to intersect a first plane, each magnetic oscillator of the first set of magnetic oscillators having a magnetic moment pointing in a first direction, the first set of magnetic oscillators having a first summed magnetic moment comprising a time-varying component and a time-invariant component; and
a second set of magnetic oscillators positioned to intersect a second plane different from the first plane, each magnetic oscillator of the second set of magnetic oscillators having a magnetic moment pointing in a second direction, the second set of magnetic oscillators having a second summed magnetic moment comprising a time-varying component and a time-invariant component,
wherein the time-invariant component of the first summed magnetic moment and the time-invariant component of the second summed magnetic moment have substantially equal magnitudes and point in substantially opposite directions.

2 . The power receiver of claim 1 , wherein the plurality of magnetic oscillators is arranged in a three-dimensional array.

3 . The power receiver of claim 1 , wherein the at least one current circuit comprises at least one coil surrounding at least a portion of the plurality of magnetic oscillators.

4 . The power receiver of claim 1 , wherein an impedance of the at least one current circuit has an imaginary component that is equal to zero at a frequency substantially equal to the mechanical resonant frequency.

5 . The power receiver of claim 1 , further comprising at least one substrate mechanically coupled to the plurality of magnetic oscillators.

6 . The power receiver of claim 5 , wherein the at least one substrate comprises a silicon substrate.

7 . The power receiver of claim 1 , wherein the plurality of magnetic oscillators is a micro-electro-mechanical system (MEMS) structure.

8 . The power receiver of claim 1 , wherein each magnetic oscillator of the plurality of magnetic oscillators comprises a movable magnetic element configured to rotate about an axis in response to a torque applied to the movable magnetic element by the first magnetic field.

9 . The power receiver of claim 8 , wherein the movable magnetic element comprises at least one spring configured to apply a restoring force to the movable magnetic element upon rotation of the movable magnetic element.

10 . A method of receiving wireless power from at least one power transmitter, the method comprising:
generating, via a plurality of magnetic oscillators, a first time-varying magnetic field in response to exposure to a second time-varying second magnetic field, wherein each magnetic oscillator of the plurality of magnetic oscillators has a mechanical resonant frequency substantially equal to a first frequency; and generating a time-varying electric current in response to exposure to the first time-varying magnetic field, the first time-varying magnetic field having the first frequency, wherein the plurality of magnetic oscillators comprises:
a first set of magnetic oscillators positioned to intersect a first plane, each magnetic oscillator of the first set of magnetic oscillators having a magnetic moment pointing in a first direction, the first set of magnetic oscillators having a first summed magnetic moment comprising a time-varying component and a time-invariant component; and
a second set of magnetic oscillators positioned to intersect a second plane different from the first plane, each magnetic oscillator of the second set of magnetic oscillators having a magnetic moment pointing in a second direction, the second set of magnetic oscillators having a second summed magnetic moment comprising a time-varying component and a time-invariant component,
wherein the time-invariant component of the first summed magnetic moment and the time-invariant component of the second summed magnetic moment have substantially equal magnitudes and point in substantially opposite directions.

11 . The method of claim 10 , wherein an impedance of the at least one circuit has an imaginary component that is equal to zero at a frequency substantially equal to the mechanical resonant frequency.

12 . The method of claim 10 , further comprising rotating a movable magnetic element of each magnetic oscillator of the plurality of magnetic oscillators about an axis in response to a torque applied to the movable magnetic element by the first magnetic field.

13 . The method of claim 12 , further comprising applying a restoring force to the movable magnetic element upon rotation of the movable magnetic element.

14 . A power receiver configured to wirelessly receive power from at least one power transmitter, the power receiver comprising:
a plurality of means for generating a first time-varying magnetic field in response to exposure to a second time-varying second magnetic field, wherein each means for generating has a mechanical resonant frequency substantially equal to a first frequency; and at least one means for generating a time-varying electric current in response to exposure to the first time-varying magnetic field, the first time-varying magnetic field having the first frequency, wherein the plurality of means for field generating comprises:
a first set of means for field generating positioned to intersect a first plane, each means for field generating of the first set of means for field generating having a magnetic moment pointing in a first direction, the first set of means for field generating having a first summed magnetic moment comprising a time-varying component and a time-invariant component; and
a second set of means for field generating positioned to intersect a second plane different from the first plane, each means for field generating of the second set of means for field generating having a magnetic moment pointing in a second direction, the second set of means for field generating having a second summed magnetic moment comprising a time-varying component and a time-invariant component,
wherein the time-invariant component of the first summed magnetic moment and the time-invariant component of the second summed magnetic moment have substantially equal magnitudes and point in substantially opposite directions.

15 . The power receiver of claim 14 , wherein the at least one means for current generating comprises at least one coil surrounding at least a portion of the plurality of means for field generating.

16 . The power receiver of claim 14 , wherein an impedance of the at least one means for current generating has an imaginary component that is equal to zero at a frequency substantially equal to the mechanical resonant frequency.

17 . The power receiver of claim 14 , wherein the plurality of means for field generating is a micro-electro-mechanical

Assignees

• Qualcomm Inc

Inventors

• Widmer Hanspeter
• Cook Nigel P
• Bittner Markus

Classifications

• H02J7/32

  for charging batteries from a charging set comprising a non-electric prime mover {rotating at constant speed} · CPC title

• H02J50/10

  using inductive coupling · CPC title

• H01F38/14

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

• H03B15/006

  using spin transfer effects or giant magnetoresistance · CPC title

• H04B5/0037

  Electricity · mapped topic