Multimode wireless power transmitters and related methods

Abstract

A wireless power transmitter comprises a bridge inverter configured to receive a DC power signal and generate an AC power signal according to an operating frequency, a resonant tank configured to receive the AC power signal and generate an electromagnetic field responsive thereto, and control logic configured to cause the resonant tank to reconfigure and adjust its resonant frequency for a particular receiver type of a wireless power receiver with which a mutual inductance relationship is desired. A method comprises determining a receiver type for a wireless power receiver with which it is desired to establish a mutual inductance relationship for wireless power transfer, and generating a wireless power signal with a wireless power transmitter having an operating frequency and resonant tank that is adjusted for a particular receiver type.

What is claimed is: 
     
         1 - 16 . 
     
     
         17 . A method for operating a multimode wireless power transmitter, the method comprising:
 determining a receiver type for a wireless power receiver with which it is desired to establish a mutual inductance relationship for wireless power transfer; and   generating a wireless power signal with a wireless power transmitter having an operating frequency and resonant tank that is adjusted for a particular receiver type.   
     
     
         18 . The method of  claim 17 , wherein generating the wireless power signal includes at least one of:
 adjusting a capacitance of the resonant tank while maintaining a fixed inductance;   adjusting a inductance of the resonant tank while maintaining a fixed capacitance; and   adjusting both a capacitance an inductance of the resonant tank.   
     
     
         19 . The method of  claim 17 , wherein determining the receiver type includes:
 transmitting a first communication signal from the wireless power transmitter to the wireless power receiver, the first communication signal having a first characteristic associated with a first receiver type; and   if no response is received by the wireless power transmitter during a waiting period, reconfiguring the resonant tank and operating frequency and transmitting second communication signal from the wireless power transmitter to the wireless power receiver, the second communication signal having a second characteristic associated with a second receiver type.   
     
     
         20 . The method of  claim 19 , wherein the first characteristic and the second characteristic differ by at least one of an operating frequency, an encoding/decoding scheme, and ping structure.