Wireless power transmission system and power transmission apparatus

• US 10,298,070 B2
• Filed: 01/10/2018
• Issued: 05/21/2019
• Est. Priority Date: 09/10/2015
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Sakata, Tsutomu, Kanno, Hiroshi
• Primary Examiner(s): Corrielus, Jean B
• Application Number:
  US15/867,250
• Publication Number:
  US 20180131237A1
• Time in Patent Office: 496 Days
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/48 Transceivers
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A power transmission apparatus includes an inverter circuit, a power transmission antenna that wirelessly transmits alternating current power output from the inverter circuit, and a power transmission control circuit that causes the inverter circuit to output the alternating current power. The power transmission control circuit causes the inverter circuit to output the alternating current power as binary communication data by varying frequency of the alternating current power output from the inverter circuit between a first frequency and a second frequency, and performs amplitude control for eliminating a difference between amplitude of voltage of the alternating current power at a time when the frequency is the first frequency and amplitude of the voltage of the alternating current power at a time when the frequency is the second frequency.

Claims

1. A power reception apparatus comprising:

a power reception antenna that receives alternating current power wirelessly transmitted, the alternating current power having a first frequency as one of a first binary communication data and a second frequency as another of the first binary communication data, and

a power reception amplitude modulator that varies amplitude of voltage of the alternating current power input to a power transmission antenna between a first amplitude and a second amplitude,

wherein, to transmit second binary communication data from the power reception antenna through electromagnetic coupling, the power reception amplitude modulator selects the first amplitude as one of the second binary communication data and the second amplitude as another of the second binary communication data, and

wherein the transmission of the second binary communication data from the power reception antenna is performed at the same time as the transmission of the first binary communication data to the power reception antenna.

2. The power reception apparatus according to claim 1,

wherein the power reception apparatus includes a frequency detector that detects frequency of the alternating current power received by the power reception antenna.

3. The power reception apparatus according to claim 2,

wherein the power reception apparatus includes a power reception demodulator that demodulates the alternating current power on a basis of the detected frequency to obtain the first binary communication data.

4. The power reception apparatus according to claim 1,

wherein the electromagnetic coupling includes magnetic field coupling or electric field coupling.

5. The power reception apparatus according to claim 1,

wherein the power reception amplitude modulator varies the amplitude of voltage of the alternating current power input to the power transmission antenna between the first amplitude and the second amplitude through load modulation.

6. The power reception apparatus according to claim 1,

wherein the power reception apparatus includes a rectifier that converts the alternating current power into direct current (DC) power for supply to a load.

7. The power reception apparatus according to claim 6,

wherein the power reception amplitude modulator varies the amplitude of voltage of the alternating current power input to the power transmission antenna between the first amplitude and the second amplitude through load modulation, and

wherein the power reception amplitude modulator is connected between the power reception antenna and the rectifier.

8. The power reception apparatus according to claim 6,

wherein the power reception amplitude modulator varies the amplitude of voltage of the alternating current power input to the power transmission antenna between the first amplitude and the second amplitude through load modulation, and

wherein the power reception amplitude modulator is connected between the rectifier and the load.

9. A power reception apparatus for a wireless power transmission system including a power transmission apparatus and a power reception apparatus, the power transmission apparatus comprising:

an inverter circuit that converts first direct current power supplied from a power supply into alternating current power and outputs the alternating current power;

a power transmission antenna that wirelessly transmits the alternating current power output from the inverter circuit; and

a power transmission control circuit that causes the inverter circuit to output the alternating current power and outputs the alternating current power as binary communication data by varying frequency of the alternating current power output from the inverter circuit between a first frequency and a second frequency,

wherein the power reception apparatus includes

a power reception antenna that receives the alternating current power wirelessly transmitted from the power transmission antenna, and

a power reception amplitude modulator that varies amplitude of voltage of the alternating current power input to the power transmission antenna between a first amplitude and a second amplitude,

wherein, when transmitting first binary communication data from the power transmission antenna to the power reception antenna through electromagnetic coupling between the power transmission antenna and the power reception antenna, the power transmission control circuit selects the first frequency as one of the first binary communication data and the second frequency as another of the first binary communication data,

wherein, when transmitting second binary communication data from the power reception antenna to the power transmission antenna through the electromagnetic coupling, the power reception amplitude modulator selects the first amplitude as one of the second binary communication data and the second amplitude as another of the second binary communication data, and

wherein the power transmission control circuit performs, using the inverter circuit, amplitude control for eliminating a difference between a third amplitude of the voltage of the alternating current power at a time when the frequency of the alternating current power is the first frequency and a fourth amplitude of the voltage of the alternating current power at a time when the frequency of the alternating current power is the second frequency.