Power reception control device, power reception device, non-contact power transmission system, electronic instrument and power reception control method

• US 8,836,273 B2
• Filed: 11/29/2012
• Issued: 09/16/2014
• Est. Priority Date: 07/17/2007
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Yoda, Kentaro, Kamijo, Takahiro, Onishi, Kota, Kamiyama, Masayuki, Shiozaki, Nobutaka
• Primary Examiner(s): WILLIAMS, ARUN C
• Application Number:
  US13/689,240
• Publication Number:
  US 20130088091A1
• Time in Patent Office: 656 Days
• Field of Search: 320/107, 320/108
• US Class Current: 320/105
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02J 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source

Abstract

A power reception control device provided in a power reception device of a non-contact power transmission system includes a power-reception-side control circuit that controls an operation of the power reception device, and a power supply control signal output terminal that supplies a power supply control signal to a charge control device, the power supply control signal controlling power supply to a battery. The power-reception-side control circuit controls a timing at which the power supply control signal (ICUTX) is output from the power supply control signal output terminal. The operation of the charge control device is compulsorily controlled using the power supply control signal (ICUTX).

Claims

1. A power reception control device includable in a non-contact power transmission system that performs non-contact power transmission from a power transmission device to a power reception device through a primary coil and a secondary coil, the power reception device supplying power to a first load that is electrically connected to a power reception section of the power reception control device, the power reception control device comprising:

the power reception section that converts an induced voltage in the secondary coil into a direct-current voltage,

a load modulation section that modulates a second load of the power reception section; and

a power-reception-side control circuit that controls an operation of the power reception device,

the load modulation section being configured to transmit information from the power reception device to the power transmission device through the secondary coil to the primary coil utilizing load modulation of the second load, and

the power-reception-side control circuit being configured to reduce the power supplied from the power reception section to the first load when the power-reception-side control circuit controls the load modulation section to transmit the information from the power reception device to the power transmission device.

2. The power reception control device as defined in claim 1,

the power-reception-side control circuit being configured to transmit the information while reducing the power supplied to the first load when the power-reception-side control circuit has determined that the power supplied to the first load is larger than a given value.

3. A power reception device, comprising:

the power reception control device as defined in claim 1; and

a charge control device that controls power supplied to a battery, the first load comprising the battery, wherein

the power-reception-side control circuit is configured to supply power to the charge control device even when the power-reception-side control circuit has reduced the power supplied to the battery.

4. The power reception control device as defined in claim 1,

the power-reception-side control circuit being configured to transmit a foreign object detection pattern that allows the power transmission device to detect a takeover state by causing the load modulation section to modulate the second load, the takeover state being a state in which the power transmission device:

(1) regards a foreign object placed between the primary coil and the secondary coil as the power reception device and (2) continues power transmission, and

the power transmission device being configured to detect the foreign object by monitoring the foreign object detection pattern of a waveform of the primary coil.

5. The power reception control device as defined in claim 1,

the power-reception-side control being configured to create a load reduction period in which the power supplied to the first load is reduced, and being configured to cause the load modulation section to perform load modulation during the load reduction period.

6. An integrated circuit device, comprising:

the power reception control device as defined in claim 1.

7. An electronic instrument, comprising:

the power reception control device as defined in claim 1;

the second coil; and

the first load including a battery.

8. A non-contact power transmission system comprising:

the power reception device including the power reception control device as defined in claim 1;

the power transmission device;

the primary coil; and

the secondary coil.

9. A power reception control method for a non-contact power transmission system that performs non-contact power transmission from a power transmission device to a power reception device through a primary coil and a secondary coil, the power reception device supplying power to a first load that is electrically connected to a power reception section, the power reception method comprising:

operating the power reception section and converting an induced voltage in the secondary coil into a direct-current voltage;

supplying a power to the first load;

modulating a second load of the power reception section;

transmitting information from the power reception device to the power transmission device through the secondary coil to the primary coil utilizing a load modulation of the second load,

reducing the power supplied from the power reception section to the first load when the information is transmitted from the power reception device to the power transmission device.

10. The power reception control method as defined in claim 9, further comprising:

transmitting the information while reducing the power supplied to the first load when the power supplied to the first load is larger than a given value.