RADIO POWER TRANSMITTING APPARATUS AND RADIO POWER TRANSMITTING SYSTEM

• US 20120242161A1
• Filed: 02/16/2012
• Published: 09/27/2012
• Est. Priority Date: 03/22/2011
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Deguchi, Noritaka, Takeda, Daisuke, Sakata, Ren, Shoki, Hiroki, KUDO, Hiroki
• Granted Patent: US 8,874,031 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• 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 5/79 for data transfer in combination with power transfer

Abstract

There is provided a radio power transmitting apparatus including: a power transmitting coil, a band signal generating unit, a reflected signal measuring unit, an oscillator and a communication control unit. The coil is supplied with a signal and transmits the signal to a power receiving coil on a radio power receiving apparatus through magnetic coupling. The generating unit generates a band signal having an allowable transmission band and supplies the band signal to the power transmitting coil. The reflected signal measuring unit measures a reflected signal of the band signal from the power transmitting coil. The oscillator generates a carrier signal having a controllable oscillating frequency. The control unit determines a transmission frequency based on a frequency characteristic of the reflected signal and performs control so that a transmission signal generated by modulating the carrier signal of the transmission frequency is supplied to the power transmitting coil.

Claims

1. A radio power transmitting apparatus comprising:

a power transmitting coil configured to be supplied with a signal and transmit the signal to a power receiving coil on a radio power receiving apparatus through magnetic coupling;

a band signal generating unit configured to generate a band signal having an allowable transmission band and supply the band signal to the power transmitting coil as the signal;

a reflected signal measuring unit configured to measure a reflected signal of the band signal from the power transmitting coil;

an oscillator configured to generate a carrier signal having a controllable oscillating frequency; and

a communication control unit configured to determine a transmission frequency based on a frequency characteristic of the reflected signal and perform control so that a transmission signal generated by modulating the carrier signal of the transmission frequency is supplied to the power transmitting coil as the signal.

2. The apparatus according to claim 1, wherein the communication control unit determines a frequency of the carrier signal for load modulation to be transmitted to the radio power receiving apparatus based on the frequency characteristic of the reflected signal, and

the carrier signal of the determined frequency is supplied to the power transmitting coil.

3. The apparatus according to claim 1, wherein the transmission frequency is a frequency at which amplitude of the reflected signal becomes a local minimum.

4. The apparatus according to claim 2, wherein the frequency of the carrier signal is a frequency at which amplitude of the reflected signal becomes a local minimum.

5. The apparatus according to claim 1, wherein the transmission signal is generated by mufti-level modulating the carrier signal of the transmission frequency.

6. The apparatus according to claim 2, further comprising a symbol cycle control unit configured to determine a symbol cycle of the carrier signal based on the frequency characteristic, wherein the communication control unit performs control so that the carrier signal is transmitted in the symbol cycle.

7. The apparatus according to claim 1, further comprising a power transmitting unit configured to generate a power signal and give the power signal to the power transmitting coil,

wherein the power transmitting coil transmits the power signal to the power receiving coil through magnetic coupling and

impedance matching is performed with the radio power receiving apparatus using a coupling coefficient between the power transmitting coil and the power receiving coil wherein the coupling coefficient is determined based on the frequency characteristic.

8. A radio power transmitting system comprising:

the radio power transmitting apparatus according to claim 2; and

a radio power receiving apparatus,

wherein the radio power receiving apparatus comprises;

the power receiving coil;

a power receiving demodulation unit configured to demodulate the transmission signal obtained by the power receiving coil; and

a power receiving modulation unit configured to load-modulate the carrier signal obtained by the power receiving coil.

9. The system according to claim 8, wherein the power receiving modulation unit performs modulation according to any one of phase modulation, amplitude modulation, frequency modulation and quadrature phase amplitude modulation.

10. The system according to claim 8,

wherein the radio power transmitting apparatus further comprises a power transmitting unit configured to generate a power signal and give the power signal to the power transmitting coil,

the power transmitting coil transmits the power signal to the power receiving coil through magnetic coupling,

the radio power receiving apparatus further comprises a power receiving unit configured to use the power signal received by the power receiving coil, and

both of power transmission and signal communication are performed through time-division or frequency-division multiplexing between the radio power transmitting apparatus and the radio power receiving apparatus.