×

Wireless power feeder, wireless power receiver, and wireless power transmission system

  • US 8,829,725 B2
  • Filed: 03/18/2011
  • Issued: 09/09/2014
  • Est. Priority Date: 03/19/2010
  • Status: Active Grant
First Claim
Patent Images

1. A wireless power feeder that wirelessly feeds power from a power feeding coil to a power receiving coil using a magnetic field resonance phenomenon between the power feeding coil and the power receiving coil, the feeder comprising:

  • the power feeding coil;

    a power transmission control circuit that feeds AC power to the power feeding coil at a drive frequency so as to make the power feeding coil feed the AC power to the power receiving coil;

    a phase detection circuit that detects a phase difference between voltage and current phases of the AC power;

    a signal receiving coil that receives, from the AC power receiving side, an output signal having a duty ratio indicating an output level; and

    a signal adjustment circuit that DC-converts the output signal in accordance with the duty ratio,the power transmission control circuit adjusting the drive frequency so as to reduce the phase difference,the phase detection circuit performing ex-post adjustment of the detected value of one or both of the voltage and current phases in accordance with a signal level of the DC-converted output signal.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×