Wireless power supply receiver-transmitter device, wireless power supply receiver and wireless power supply transmitter

A wireless power supply receiver comprising:

• a power receiver unit configured to wirelessly receive electric power transmitted from a wireless power supply transmitter, the power receiver unit comprising:
• a secondary-side coil;
• a secondary-side resonance capacitor connected to the secondary-side coil, the secondary-side resonance capacitor configured to be tuned with the secondary-side coil in a predetermined wireless power transmission carrier frequency band;
• a diode bridge circuit connected to the secondary-side resonance capacitor, the diode bridge having a positive output and a negative output;
• a first data transmitter/receiver unit configured to bidirectionally transmit and receive data through the optical communications to/from the wireless power supply transmitter, wherein
• a regulator circuit configured to output a predetermined voltage used for monitoring a power consumption state in the power receiver unit side;
• a protective transistor, a drain of the protective transistor being connected to the positive output of the diode bridge;
• a first resistor having a first end connected to a source of the protective transistor and a second end connected to the negative output of the diode bridge;
• and
• a Zener diode having a cathode and an anode, the cathode of the Zener diode being connected to the positive output of the diode bridge, and an anode of the Zener diode being connected to the gate of the protective transistor;
• a second resistor having a first end connected to the anode of the Zener diode and the gate of the protective transistor and a second end connected to a negative output of the diode bridge;
• a feedback unit configured to detect a state of coupling between the power receiver unit and a power transmitter unit in the wireless power supply transmitter by determining a coupling factor between the power receiver unit and the power transmitter unit on the basis of at least one of a current flowing into the secondary-side coil and a voltage applied thereon, the feedback unit further configured to terminate the power transmission from the power transmitter unit to the power receiver unit and further configured to disconnect data communications between the first data transmitter/receiver unit and the second data transmitter/receiver unit if a voltage higher than a predetermined voltage is detected in the power transmitter unit side;
• wherein
• the power transmitter unit uses a gallium nitride based field effect transistor as a switching device for driving a primary-side coil, and maximum transmitting efficiency ηmax is expressed with the following equation:
• ηmax=α/[1+(1+α)1/2]2
• where α is a coil parameter, and the coil parameter α is equal to or greater than approximately 104.

A wireless power supply receiver comprising:

• a power receiver unit configured to wirelessly receive electric power transmitted from a wireless power supply transmitter, the power receiver unit comprising:
• a secondary-side coil;
• a secondary-side resonance capacitor connected to the secondary-side coil, the secondary-side resonance capacitor configured to be tuned with the secondary-side coil in a predetermined wireless power transmission carrier frequency band;
• a diode bridge circuit connected to the secondary-side resonance capacitor, the diode bridge having a positive output and a negative output;
• a first resistor having a first end connected to the positive output of the diode bridge and a second end connected to the negative output of the diode bridge;
• a first capacitor having a first end connected to the positive output of the diode bridge and a second end connected to the negative output of the diode bridge;
• a first data transmitter/receiver unit configured to bidirectionally transmit and receive data through the optical communications to/from the wireless power supply transmitter, wherein
• a regulator circuit configured to output a predetermined voltage used for monitoring a power consumption state in the power receiver unit side;
• a resistor disposed between the diode bridge circuit and the regulator circuit, the resistor used for converting excess power into a heat by feeding the excess power thereto if the excess power from the wireless power supply transmitter is received by the wireless power supply receiver;
• and
• a feedback unit configured to detect a state of coupling between the power receiver unit and a power transmitter unit in the wireless power supply transmitter by determining a coupling factor between the power receiver unit and the power transmitter unit on the basis of at least one of a current flowing into the secondary-side coil and a voltage applied thereon, the feedback unit further configured to terminate the power transmission from the power transmitter unit to the power receiver unit and further configured to disconnect data communications between the first data transmitter/receiver unit and the second data transmitter/receiver unit if a voltage higher than a predetermined voltage is detected in the power transmitter unit side;
• wherein
• the power transmitter unit uses a gallium nitride based field effect transistor as a switching device for driving a primary-side coil, and maximum transmitting efficiency ηmax is expressed with the following equation:
• ηmax=α/[1+α)1/2]2
• where α is a coil parameter, and the coil parameter α is equal to or greater than approximately 104.