FEED UNIT AND FEED SYSTEM

• US 20140346890A1
• Filed: 10/12/2012
• Published: 11/27/2014
• Est. Priority Date: 10/21/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Haseno, Shinichi, Uramoto, Yoichi
• Granted Patent: US 9,847,813 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H01F 2038/143 for signals
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02H 3/20 responsive to excess voltage
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence
• CPC Class Codes: H02M 7/4815 Resonant converters H02M7/4811 and H02M7/4826 take precedence
• CPC Class Codes: H02M 7/537 using semiconductor devices only, e.g. single switched pulse inverters
• CPC Class Codes: H03C 1/00 Amplitude modulation H03C5/00, H03C7/00 take precedence
• CPC Class Codes: H03K 7/08 Duration or width modulation ; Duty cycle modulation
• CPC Class Codes: H03L 5/02 of power
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: H04L 5/22 using time-division multiplexing
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A feed unit includes: a power transmission section configured to perform power transmission with use of a magnetic field or an electronic field; a power limiting section provided on a power supply line from an external power source to the power transmission section; and a control section provided on a side closer to the external power source than the power limiting section, and including a power transmission control section, the power transmission control section being configured to control the power transmission.

Claims

1. A feed unit comprising:

a power transmission section configured to perform power transmission with use of a magnetic field or an electric field;

a power limiting section provided on a power supply line from an external power source to the power transmission section; and

a control section provided on a side closer to the external power source than the power limiting section, and including a power transmission control section, the power transmission control section being configured to control the power transmission.

2. The feed unit according to claim 1, wherein the control section includes the power transmission control section and a control section for data transmission.

3. The feed unit according to claim 1, further comprising an operation stop section that is configured to forcibly stop the power transmission irrespective of power transmission control by the power transmission control section when an abnormal state of the unit is detected.

4. The feed unit according to claim 3, wherein the operation stop section renders a control signal for the power transmission invalid to forcibly stop the power transmission.

5. The feed unit according to claim 4, wherein the operation stop section has a switching section configured to switch a state of the control signal between valid and invalid according to presence or absence of detection of the abnormal state.

6. The feed unit according to claim 3, wherein the operation stop section has a voltage detection section that is configured to detect a voltage between input and output of the power limiting section, and forcibly stops the power transmission according to magnitude of the voltage detected by the voltage detection section

7. The feed unit according to claim 6, wherein the operation stop section forcibly stops the power transmission when the detected voltage exceeds a first threshold.

8. The feed unit according to claim 7, wherein the power limiting section forcibly interrupts power supply to the power transmission section when the detected voltage also exceeds a second threshold that is larger than the first threshold.

9. The feed unit according to claim 8, wherein the power limiting section includes an error amplifier that is configured to control power limiting operation according to a potential difference between a reference voltage and a voltage corresponding to an input current from the external power source, and controls magnitude of the reference voltage to forcibly interrupt the power supply to the power transmission section when the detected voltage exceeds the second threshold.

10. The feed unit according to claim 9, wherein the power limiting section includes a transistor on the power supply line, and controls the magnitude of the reference voltage and sets the transistor to be in OFF state to forcibly interrupts the power supply to the power transmission section.

11. The feed unit according to claim 8, wherein

the first threshold defines whether the state of the unit is in a overload state during normal operation, and

the second threshold defines whether the power transmission section is in a failed state or in a destructive state.

12. The feed unit according to claim 8, wherein the operation stop section is in an inoperable state when the detected voltage exceeds the second threshold.

13. The feed unit according to claim 3, wherein

the power transmission control section controls the power transmission to allow a feeding period during which the power transmission is performed on a unit to be fed with power and a communication period during which predetermined communication is performed with the unit to be fed with power, to be set in a time-divisional manner, and

the operation stop section forcibly stops the communication when the abnormal state is detected during the communication period.

14. The feed unit according to claim 1, wherein

the power transmission control section controls the power transmission to allow a feeding period during which the power transmission is performed on a unit to be fed with power and a communication period during which predetermined communication is performed with the unit to be fed with power, to be set in a time-divisional manner, and controls power limiting operation by the power limiting section during the communication period to allow communication by amplitude modulation to be performed.

15. The feed unit according to claim 14, wherein the power limiting section performs the power limiting operation during the feeding period, and performs amplitude modification operation during the communication period.

16. The feed unit according to claim 1, further comprising

an AC signal generation section configured to generate an AC signal to perform the power transmission, wherein

the power transmission control section controls operation of the AC signal generation section to perform control of the power transmission.

17. The feed unit according to claim 16, wherein

the AC signal generation section is configured using a switching amplifier including a switching device, and

the power transmission control section uses a control signal for the power transmission to control ON-OFF operation of the switching device.

18. The feed unit according to claim 17, wherein the power transmission control section controls the power transmission to allow a feeding period during which the power transmission is performed on a unit to be fed with power and a communication period during which predetermined communication is performed with the unit to be fed with power, to be set in a time-divisional manner, and controls a duty ratio of the control signal during the communication period to allow communication by pulse width modulation to be performed.

19. The feed unit according to claim 1, wherein the power transmission section uses resonance operation to perform the power transmission.

20. A feed system provided with one or a plurality of electronic apparatuses and a feed unit configured to perform power transmission on the electronic apparatuses, the feed unit comprising:

a power transmission section configured to perform the power transmission with use of a magnetic field or an electronic field;

a power limiting section provided on a power supply line from an external power source to the power transmission section; and

a control section provided on a side closer to the external power source than the power limiting section, and including a power transmission control section, the power transmission control section being configured to control the power transmission.