Power receiving unit, power feeding control method, and feed system

• US 10,298,064 B2
• Filed: 02/10/2015
• Issued: 05/21/2019
• Est. Priority Date: 02/24/2014
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nakano, Hiroaki, Bunsen, Keigo, Kozakai, Osamu, Fujimaki, Kenichi
• Primary Examiner(s): Borroto, Alfonso Perez
• Assistant Examiner(s): Yeshaw, Esayas G
• Application Number:
  US15/119,176
• Publication Number:
  US 20170012470A1
• Time in Patent Office: 1,561 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: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

A power receiving unit of the disclosure includes: a power generation section configured to generate direct-current power, based on a power signal supplied wirelessly from a power feeding unit; and a communication section configured to set a load of the power signal in accordance with an output current of the power generation section, and to communicate with the power feeding unit by modulating the load.

Claims

1. A power receiving unit, comprising:

a power generation section configured to;

receive a power signal wirelessly from a power feeding unit; and

generate a direct-current signal based on the received power signal; and

a communication section configured to;

detect an output current of the power generation section based on the generated direct-current signal;

compare the output current of the power generation section with a threshold current value;

set a load of the power signal based on a result of the comparison; and

communicate with the power feeding unit based on modulation of the load.

2. The power receiving unit according to claim 1, wherein the communication section is further configured to:

set the load to cause an impedance of the load to be equal to a first impedance value, in a case where the output current of the power generation section is greater than the threshold current value; and

set the load to cause the impedance of the load to be equal to a second impedance value, in a case where the output current of the power generation section is less than the threshold current value, wherein the first impedance value is smaller than the second impedance value.

3. The power receiving unit according to claim 1, wherein the communication section includes:

a first switch;

a first passive element connected in series to the first switch;

a second switch; and

a second passive element connected in series to the second switch, and

wherein the communication section is further configured to;

determine one of the first switch or the second switch to be one of turned on or turned off, based on the output current of the power generation section; and

set the load based on the determination.

4. The power receiving unit according to claim 3, wherein an element value of the first passive element is different from an element value of the second passive element.

5. The power receiving unit according to claim 3, wherein each of the first passive element and the second passive element is one of a capacitor or a resistor.

6. The power receiving unit according to claim 1, wherein

the communication section includes:

a switch; and

a variable passive element connected in series to the switch, and

the communication section is further configured to vary an element value of the variable passive element based on the output current of the power generation section.

7. The power receiving unit according to claim 6, wherein the variable passive element is a variable capacitor.

8. The power receiving unit according to claim 6, wherein the variable passive element is a variable resistor.

9. The power receiving unit according to claim 1, wherein

the power generation section includes a rectifier circuit configured to:

rectify the power signal; and

generate the direct-current signal based on the rectified power signal, and

the communication section is further configured to set the load of the power signal based on the generated direct-current signal.

10. The power receiving unit according to claim 9, wherein the communication section is further configured to set the load based on an output voltage of the rectifier circuit.

11. The power receiving unit according to claim 1, wherein

the power generation section includes a regulator circuit configured to generate a direct-current power based on the direct-current signal, and

the communication section is further configured to set the load based on an output current of the regulator circuit.

14. The power receiving unit according to claim 1, wherein the communication section is further configured to:

select a modulation circuit from a plurality of modulation circuits based on the result of the comparison; and

communicate with the power feeding unit based on the selected modulation circuit.

12. A power feeding control method, comprising:

receiving a power signal wirelessly from a power feeding unit;

generating a direct-current signal based on the received power signal;

detecting an output current based on the generated direct-current signal;

comparing the output current with a threshold current value;

setting a load of the power signal based on a result of the comparison; and

communicating with the power feeding unit based on modulating the load.

13. A feed system, comprising:

a power feeding unit; and

a power receiving unit, wherein the power receiving unit comprising;

a power generation section configured to;

receive a power signal wirelessly from the power feeding unit; and

generate a direct-current signal based on the received power signal; and

a communication section configured to;

detect an output current of the power generation section based on the generated direct-current signal;

compare the output current of the power generation section with a threshold current value;

set a load of the power signal based on a result of the comparison; and

communicate with the power feeding unit based on modulation of the load.