Wireless power transmitter and wireless power receiver

• US 9,552,921 B2
• Filed: 11/27/2013
• Issued: 01/24/2017
• Est. Priority Date: 06/02/2011
• Status: Active Grant

• Current Assignee: Advantest Corporation
• Original Assignee: Adventest Corporation
• Inventors: Endo, Yuki, Furukawa, Yasuo
• Primary Examiner(s): Gannon, Levi
• Application Number:
  US14/092,813
• Publication Number:
  US 20140175894A1
• Time in Patent Office: 1,154 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

An automatic tuning assist circuit is coupled in series with a transmission antenna. A first switch and a second switch are arranged in series between a first terminal and a second terminal of the automatic tuning assist circuit. Furthermore, a third switch and a fourth switch are arranged in series between the first terminal and the second terminal. A first auxiliary capacitor is arranged between a connection node that connects the first switch and the second switch and a connection node that connects the third switch and the fourth switch. A first control unit switches on and off the first switch through the fourth switch with the same frequency as that of the driving voltage, and with a given phase difference with respect to the driving voltage.

Claims

1. A wireless power transmitting apparatus configured to transmit an electric power signal comprising any one from among an electric field, a magnetic field, and an electromagnetic field to a wireless power receiving apparatus, the wireless power transmitting apparatus comprising:

a transmission antenna comprising a transmission coil;

an automatic tuning assist circuit coupled with the transmission antenna; and

a power supply configured to apply an AC driving voltage across a series circuit that comprises the transmission antenna and the automatic tuning assist circuit,

wherein the automatic tuning assist circuit comprises;

a first terminal;

a second terminal;

a first switch and a second switch arranged in series between the first terminal and the second terminal;

a third switch and a fourth switch sequentially arranged in series between the first terminal and the second terminal such that they are arranged on a path that is in parallel with the first switch and the second switch;

a first auxiliary capacitor arranged between a connection node that connects the first switch and the second switch and a connection node that connects the third switch and the fourth switch; and

a first control unit configured to switch on and off the first switch through the fourth switch in synchronization with the driving voltage, wherein the power supply comprises;

a DC power supply; and

a first high-side switch and a first low-side switch sequentially arranged in series between an output terminal of the DC power supply and a fixed voltage terminal,

and wherein the transmission antenna and the automatic tuning assist circuit are coupled in series between a connection node that connects the first high-side switch and the first low-side switch and the fixed voltage terminal.

2. The wireless power transmitting apparatus according to claim 1, wherein the first control unit is configured to switch on and off each of the first switch through the fourth switch with the same frequency as that of the driving voltage, or otherwise with a frequency obtained by multiplying or dividing the frequency of the driving voltage by an odd number.

3. The wireless power transmitting apparatus according to claim 1, wherein the first switch through the fourth switch are each configured as a uni-directional switch,

and wherein the first control unit is configured to switch on and off the first switch through the fourth switch with a phase controlled such that no current flows through each of their inversely conducting elements.

4. The wireless power transmitting apparatus according to claim 1, wherein the first switch through the fourth switch are each configured as a bi-directional switch.

5. The wireless power transmitting apparatus according to claim 1, wherein the automatic tuning assist circuit is coupled in series with the transmission antenna via a transformer.

6. The wireless power transmitting apparatus according to claim 1, wherein the transmission antenna comprises a resonance capacitor arranged in series with the transmission coil.

7. The wireless power transmitting apparatus according to claim 1, wherein the power supply is configured to apply an AC driving voltage via a transformer across a series circuit that comprises the transmission antenna and the automatic tuning assist circuit.

8. A wireless power supply system comprising:

the wireless power transmitting apparatus according to claim 1; and

a wireless power receiving apparatus configured to receive an electric power signal from the wireless power transmitting apparatus.

20. A wireless power supply system comprising:

the wireless power transmitting apparatus according to claim 1; and

the wireless power receiving apparatus according to claim 11, configured to receive the electric power signal from the wireless power transmitting apparatus.

9. A wireless power transmitting apparatus configured to transmit an electric power signal comprising any one from among an electric field, a magnetic field, and an electromagnetic field to a wireless power receiving apparatus, the wireless power transmitting apparatus comprising:

a transmission antenna comprising a transmission coil;

an automatic tuning assist circuit coupled with the transmission antenna; and

a power supply configured to apply an AC driving voltage across a series circuit that comprises the transmission antenna and the automatic tuning assist circuit,

wherein the automatic tuning assist circuit comprises;

a first terminal;

a second terminal;

a first switch and a second switch arranged in series between the first terminal and the second terminal;

a third switch and a fourth switch sequentially arranged in series between the first terminal and the second terminal such that they are arranged on a path that is in parallel with the first switch and the second switch;

a first auxiliary capacitor arranged between a connection node that connects the first switch and the second switch and a connection node that connects the third switch and the fourth switch; and

a first control unit configured to switch on and off the first switch through the fourth switch in synchronization with the driving voltage, and wherein the power supply comprises;

a DC power supply;

a first high-side switch and a first low-side switch sequentially arranged in series between an output terminal of the DC power supply and a fixed voltage terminal; and

a second high-side switch and a second low-side switch sequentially arranged in series between the output terminal of the DC power supply and the fixed voltage terminal,

and wherein the transmission antenna and the automatic tuning assist circuit are coupled in series between a connection node that connects the first high-side switch and the first low-side switch and a connection node that connects the second high-side switch and the second low-side switch.

10. A wireless power supply system comprising:

the wireless power transmitting apparatus according to claim 9; and

a wireless power receiving apparatus configured to receive an electric power signal from the wireless power transmitting apparatus.

11. A wireless power receiving apparatus configured to receive an electric power signal comprising any one from among an electric field, a magnetic field, and an electromagnetic field, transmitted from a wireless power transmitting apparatus, the wireless power receiving apparatus comprising:

a reception antenna comprising a reception coil; and

an automatic tuning assist circuit coupled with the reception antenna;

wherein the automatic tuning assist circuit comprises;

a first terminal;

a second terminal;

a fifth switch and a sixth switch arranged in series between the first terminal and the second terminal;

a seventh switch and an eighth switch sequentially arranged in series between the first terminal and the second terminal such that they are arranged in parallel with the fifth switch and the sixth switch;

a second auxiliary capacitor arranged between a connection node that connects the fifth switch and the sixth switch and a connection node that connects the seventh switch and the eighth switch; and

a second control unit configured to switch on and off the fifth switch through the eighth switch, wherein the second control unit is configured to switch on and off each of the fifth switch through the eighth switch with the same frequency as that of the electric power signal, or otherwise with a frequency obtained by multiplying or dividing the frequency of the electric power signal by an odd number.

12. The wireless power receiving apparatus according to claim 11, wherein a load to which electric power is to be supplied is connected to the second auxiliary capacitor.

13. The wireless power receiving apparatus according to claim 11, wherein a load to which electric power is to be supplied is connected to the reception antenna.

14. The wireless power receiving apparatus according to claim 11, further comprising a transformer having a primary winding connected in series with the reception antenna,

wherein a load to which electric power is to be supplied is connected to a secondary winding of the transformer.

15. The wireless power receiving apparatus according to claim 11, wherein the fifth switch through the eighth switch are each configured as a uni-directional switch,

and wherein the second control unit is configured to switch on and off the fifth switch through the eighth switch with a phase controlled such that no current flows through each of their inversely conducting elements.

16. The wireless power receiving apparatus according to claim 11, wherein the fifth switch through the eighth switch are each configured as a bi-directional switch.

17. The wireless power receiving apparatus according to claim 11, wherein the automatic tuning assist circuit is coupled in series with the reception antenna via a transformer.

18. The wireless power receiving apparatus according to claim 11, wherein the reception antenna comprises a resonance capacitor arranged in series with the reception coil.

19. A wireless power supply system comprising:

a wireless power transmitting apparatus configured to transmit an electric power signal comprising any one from among an electric field, a magnetic field, and an electromagnetic field; and

the wireless power receiving apparatus according to claim 11, configured to receive the electric power signal.

21. A wireless power receiving apparatus configured to receive an electric power signal comprising any one from among an electric field, a magnetic field, and an electromagnetic field, transmitted from a wireless power transmitting apparatus, the wireless power receiving apparatus comprising:

a reception antenna comprising a reception coil; and

an automatic tuning assist circuit coupled with the reception antenna;

wherein the automatic tuning assist circuit comprises;

a first terminal;

a second terminal;

a fifth switch and a sixth switch arranged in series between the first terminal and the second terminal;

a seventh switch and an eighth switch sequentially arranged in series between the first terminal and the second terminal such that they are arranged in parallel with the fifth switch and the sixth switch;

a second auxiliary capacitor arranged between a connection node that connects the fifth switch and the sixth switch and a connection node that connects the seventh switch and the eighth switch; and

a second control unit configured to switch on and off the fifth switch through the eighth switch, wherein the second control unit is configured to drive the fifth switch through the eighth switch with a predetermined phase difference with respect to a driving voltage applied to a transmission antenna of the wireless power transmitting apparatus.

22. A wireless power supply system comprising:

a wireless power transmitting apparatus configured to transmit an electric power signal comprising any one from among an electric field, a magnetic field, and an electromagnetic field; and

the wireless power receiving apparatus according to claim 21, configured to receive the electric power signal.

23. An automatic tuning assist circuit employed in a wireless power receiving apparatus configured to receive an electric power signal comprising any one from among an electric field, a magnetic field, or an electromagnetic field transmitted from a wireless power transmitting apparatus, and coupled with a reception coil, the automatic tuning assist circuit comprising:

a fifth switch and a sixth switch arranged in series between the first terminal and the second terminal;

a seventh switch and an eighth switch sequentially arranged in series between the first terminal and the second terminal such that they are arranged in parallel with the fifth switch and the sixth switch;

a second auxiliary capacitor arranged between a connection node that connects the fifth switch and the sixth switch and a connection node that connects the seventh switch and the eighth switch; and

a second control unit configured to switch on and off the four switches so as to generate a capacitor voltage across of the aforementioned second auxiliary capacitor, and to apply, to the reception coil, a correction voltage that corresponds to the capacitor voltage that develops at the aforementioned second auxiliary capacitor, wherein the second control unit is configured to switch on and off each of the fifth switch through the eighth switch with the same frequency as that of the electric power signal, or otherwise with a frequency obtained by multiplying or dividing the frequency of the electric power signal by an odd number.

24. A wireless power receiving apparatus configured to receive an electronic power signal comprising an electric field, magnetic field, or electromagnetic field, transmitted from a wireless power transmitting apparatus, the wireless power receiving apparatus comprises:

a reception antenna comprising a reception coil; and

the automatic tuning assist circuit according to claim 23, coupled with the reception antenna.

25. An automatic tuning assist circuit employed in a wireless power receiving apparatus configured to receive an electric power signal comprising any one from among an electric field, a magnetic field, or an electromagnetic field transmitted from a wireless power transmitting apparatus, and coupled with a reception coil, the automatic tuning assist circuit comprising:

a fifth switch and a sixth switch arranged in series between the first terminal and the second terminal;

a seventh switch and an eighth switch sequentially arranged in series between the first terminal and the second terminal such that they are arranged in parallel with the fifth switch and the sixth switch;

a second auxiliary capacitor arranged between a connection node that connects the fifth switch and the sixth switch and a connection node that connects the seventh switch and the eighth switch; and

a second control unit configured to switch on and off the four switches so as to generate a capacitor voltage across of the aforementioned second auxiliary capacitor, and to apply, to the reception coil, a correction voltage that corresponds to the capacitor voltage that develops at the aforementioned second auxiliary capacitor, wherein the second control unit is configured to drive the fifth switch through the eighth switch with a predetermined phase difference with respect to a driving voltage applied to a transmission antenna of the wireless power transmitting apparatus.