Patent ID: 8836170

Claim:
A wireless power feeding system comprising: a wireless power feeding device comprising: a power feeding device transmission/reception circuit portion; and a signal processing circuit portion having a resonant frequency detection function and a power transmission control function; a wireless power receiver comprising: a power receiver transmission/reception circuit portion; a signal processing circuit portion; and a power storage portion comprising a secondary battery, wherein the wireless power feeding device is configured to: receive a detection signal transmitted by the power receiver, the detection signal comprising a plurality of signals each having a different frequency; determining a resonant frequency of the power receiver based on the detection signal; adjust a frequency of a power signal to be transmitted by the power feeding device to the power receiver, based on the resonant frequency of the power receiver; and transmit the power signal to the power receiver; and wherein the wireless power receiver is configured to: transmit the detection signal comprising the plurality of signals each having a different frequency to the power feeding device; receive the power signal having a frequency adjusted to the resonant frequency of the wireless power receiver; and store power of the power signal in the secondary battery of the power storage portion.