System for wireless power charging

Abstract

A method may comprise determining a coupling factor between a coil of a transmitter and a coil of a relay based on a joint resonance frequency between the coil of the transmitter and the coil of the relay. The determining may occur when the coil of the relay and the coil of the transmitter are separated by a medium. The transmitter may inductively transmit power for wirelessly charging a device located near the relay. An operating frequency range, having a minimal operating frequency and a maximal operating frequency, may be determined based on the coupling factor. Power may be inductively transmitted in accordance with the minimal operating frequency and the maximal operating frequency.

What is claimed is: 
     
         1 . A method comprising:
 determining a coupling factor between a coil of a transmitter and a coil of a relay, wherein the coupling factor is determined based on a joint resonance frequency between the coil of the transmitter and the coil of the relay.   
     
     
         2 . The method of  claim 1 , wherein the determining occurs when the coil of the relay and the coil of the transmitter are separated by a medium. 
     
     
         3 . The method of  claim 1 , further comprising:
 inductively transmitting power for wirelessly charging a device.   
     
     
         4 . The method of  claim 3 , further comprising:
 determining an operating frequency range, having a minimal operating frequency and a maximal operating frequency, based on the coupling factor, wherein the power is inductively transmitted in accordance with the minimal operating frequency and the maximal operating frequency.   
     
     
         5 . The method of  claim 4 , wherein the operating frequency range is determined based on the joint resonance frequency and an offset indicating that the operating frequency range is higher or lower than the joint resonance frequency. 
     
     
         6 . The method of  claim 1 , further comprising:
 operating the transmitter while sweeping a plurality of operating frequencies; and   measuring an output alternating current for each operating frequency of the plurality of operating frequencies.   
     
     
         7 . The method of  claim 4 , wherein the operating frequency range is determined based on at least one minimum and maximum voltage profile for a type of load. 
     
     
         8 . The method of  claim 1 , wherein a ping frequency is determined as a function of the coupling factor and the joint resonance frequency. 
     
     
         9 . A transmitter comprising:
 circuitry configured to determine a coupling factor between a coil of a transmitter and a coil of a relay, wherein the coupling factor is determined based on a joint resonance frequency between the coil of the transmitter and the coil of the relay.   
     
     
         10 . The transmitter of  claim 9 , wherein the determination of the coupling factor occurs when the transmitter and the relay are separated by a medium. 
     
     
         11 . The transmitter of  claim 9 , further comprising:
 circuitry configured to determine a ping frequency which matches one or more requirements of a device which is inductively charged by the transmitter.   
     
     
         12 . The transmitter of  claim 9 , further comprising:
 circuitry configured to sweep an operating frequency and measure an output alternating current for each one of a plurality of operating frequencies.   
     
     
         13 . The transmitter of  claim 9 , further comprising:
 determining an operating frequency range, having a minimal operating frequency and a maximal operating frequency, based on the coupling factor.   
     
     
         14 . The transmitter of  claim 9 , further comprising:
 circuitry configured to operate the transmitter and sweep a plurality of operating frequencies.   
     
     
         15 . The transmitter of  claim 9 , wherein the transmitter is configured to inductively transmit power. 
     
     
         16 . The transmitter of  claim 9 , wherein a ping frequency is determined as a function of the coupling factor. 
     
     
         17 . A method performed by a transmitter, the method comprising:
 determining a coupling factor between a coil of the transmitter and a coil of a relay, wherein the coupling factor is determined based on a joint resonance frequency between the coil of the transmitter and the coil of the relay; and   inductively transmitting power for wirelessly charging a device, based on the coupling factor.   
     
     
         18 . The method of  claim 17 , wherein the determining occurs when the coil of the relay and the coil of the transmitter are separated by a medium. 
     
     
         19 . The method of  claim 17 , further comprising:
 determining an operating frequency range, having a minimal operating frequency and a maximal operating frequency based on the coupling factor wherein the power is inductively transmitted in accordance with the minimal operating frequency and the maximal operating frequency.   
     
     
         20 . The method of  claim 17 , wherein a ping frequency is determined as a function of the coupling factor and the joint resonance frequency.