Inductive power supply system with multiple coil primary

Abstract

An inductive power supply including multiple tank circuits and a controller for selecting at least one of the tank circuits in order to wirelessly transfer power based on received power demand information. In addition, a magnet may be used to align multiple remote devices with the inductive power supply. In one embodiment, different communication systems are employed depending on which coil is being used to transfer wireless power.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
         1 . An inductive power supply for supplying wireless power to a remote device including power demand information, said inductive power supply comprising:
 a plurality of tank circuits, wherein each tank circuit includes a primary and a capacitor electrically connected in series, wherein each of said plurality of tank circuits are capable of being energized to transfer power wirelessly to the remote device;   a receiver for receiving power demand information from the remote device; and   a controller in electrical communication with said receiver and said plurality of tank circuits, said controller programmed to select at least one of said plurality of tank circuits to transfer power wirelessly to the remote device, wherein said selection is determined as a function of said power demand information received from the remote device.   
     
     
         2 . The inductive power supply of  claim 1  wherein said plurality of tank circuits includes a tank circuit with a low power primary coil, a tank circuit with a medium power primary coil, and a tank circuit with a high power primary coil. 
     
     
         3 . The inductive power supply of  claim 1  wherein said primary of each of said plurality of tank circuits is a different gauge. 
     
     
         4 . The inductive power supply of  claim 1  wherein said receiver includes at least one of a wireless communication system, at least one of said tank circuits, or any combination thereof. 
     
     
         5 . The inductive power supply of  claim 1  including a coil selector circuit for selectively energizing one or more of said plurality of tank circuits. 
     
     
         6 . The inductive power supply of  claim 1  wherein said power demand information includes a remote device ID, wherein said inductive power supply includes a memory, wherein said memory includes a look-up table, said look-up table maps remote device IDs to at least one of said plurality of primaries. 
     
     
         7 . An inductive power supply for supplying wireless power to a remote device including power demand information, said inductive power supply comprising:
 a first tank circuit including a plurality of primaries, wherein each of said plurality of primaries is capable of being energized to transfer power wirelessly to the remote device;   a receiver for receiving power demand information from the remote device, wherein said power demand information includes a power adjustment; and   a controller in electrical communication with said receiver and said tank circuit, said controller programmed to select at least one of said plurality of primaries of said tank circuit to transfer power wirelessly to the remote device, wherein said selection is determined as a function of said power adjustment received from the remote device.   
     
     
         8 . The inductive power supply of  claim 7  including a second tank circuit and a third tank circuit, each including a plurality of primaries, wherein each of said plurality of primaries of said first and second tank circuits are capable of being energized to transfer power wirelessly to the remote device, wherein said first tank circuit includes a low power primary coil, said second tank circuit includes a medium power primary coil, and said third tank circuit includes a high power primary coil. 
     
     
         9 . The inductive power supply of  claim 8  wherein said first, second, and third tank circuits are driven with a half bridge driver. 
     
     
         10 . The inductive power supply of  claim 7  wherein said receiver includes at least one of a wireless communication system, at least one of said primaries, or any combination thereof. 
     
     
         11 . The inductive power supply of  claim 7  wherein said tank circuit includes a coil selector circuit for selectively energizing one or more of the plurality of primaries. 
     
     
         12 . The inductive power supply of  claim 7  wherein said controller is programmed to determine an amount of power to be transmitted as a function of said power adjustment received from said remote device. 
     
     
         13 . The inductive power supply of  claim 12  including a memory, wherein said memory includes a threshold, said controller is programmed to select one of said plurality of primaries in response to said amount of power to be transmitted being below said threshold, and said controller is programmed to select a different one of said plurality of primaries in response to said amount of power to be transmitted being above said threshold. 
     
     
         14 . The inductive power supply of  claim 13  wherein said power demand information includes at least one of a minimum power level threshold, a maximum power level threshold, or a combination thereof. 
     
     
         15 . The inductive power supply of  claim 14  wherein said controller adjusts said threshold as a function of said at least one of said minimum power level threshold, said maximum power level threshold, or said combination thereof. 
     
     
         16 . The inductive power supply of  claim 7  wherein said remote device includes a standby mode where it demands a lower amount of power, said power demand information includes an indication that said remote device is in standby mode, and said controller selection is based at least in part on whether said remote device is in said standby mode. 
     
     
         17 . An inductive power supply for supplying wireless power to a first remote device or a second remote device, said inductive power supply comprising:
 a tank circuit including a first primary coil and a second primary coil, wherein said first primary coil and said second primary coil are arranged concentrically, wherein each of said first primary coil and said second primary coil are capable of being energizing to transfer power wirelessly;   a magnet arranged coaxially with said first primary coil and said second primary coil, wherein said magnet provides a magnetic force to assist in alignment, wherein said magnetic force of said magnet assists in aligning the first remote device with said first primary coil and wherein said magnetic force of said magnet assists in aligning the second remote device with said second primary coil.   
     
     
         18 . The inductive power supply of  claim 17  for supplying wireless power to at least one of a first remote device, a second remote device, and a third remote device:
 wherein said tank circuit includes a third primary coil, wherein said third primary coil is arranged concentrically with said first and said second primary coils, wherein said third primary coil is capable of being energized to transfer power wirelessly; and 
 wherein said magnet is arranged coaxially with said first primary coil, said second primary coil, and said third primary coil, wherein said magnetic force of said magnet assists in aligning the third remote device with the third primary coil.