FLUX MANIPULATION IN A MULTI-COIL WIRELESS CHARGER
Systems, methods and apparatus for wireless charging are disclosed. A charging device has a first plurality of charging cells provided on a charging surface, and a controller. The controller may be configured to determine that a chargeable device is positioned proximate to the plurality of charging coils, cause a first charging coil in the plurality of charging coils to produce a first electromagnetic flux and cause a second charging coil in the plurality of charging coils to produce a second electromagnetic flux. The first electromagnetic flux may have at least one characteristic that is different than a corresponding characteristic of the second electromagnetic flux.
1 . A method for operating a charging device, comprising:
determining that a chargeable device is positioned proximate to a plurality of charging coils provided in a charging surface of the charging device;
causing a first charging coil in the plurality of charging coils to produce a first electromagnetic flux; and
causing a second charging coil in the plurality of charging coils to produce a second electromagnetic flux, wherein the first electromagnetic flux has at least one characteristic that is different than a corresponding characteristic of the second electromagnetic flux.
2 . The method of claim 1 , wherein the at least one characteristic of the first electromagnetic flux includes a flux magnitude.
3 . The method of claim 1 , wherein the at least one characteristic of the first electromagnetic flux includes phase.
4 . The method of claim 1 , further comprising:
providing a first current to the first charging coil; and
providing a second current to the second charging coil, wherein the second current is greater in magnitude than the first current.
5 . The method of claim 1 , further comprising:
providing a first current to the first charging coil; and
providing a second current to the second charging coil, wherein the second current lags the first current in phase.
6 . The method of claim 1 , further comprising:
providing a first voltage to the first charging coil; and
providing a second voltage to the second charging coil, wherein the second voltage is greater than the first voltage.
7 . The method of claim 1 , further comprising:
providing a first voltage to the first charging coil; and
providing a second voltage to the second charging coil, wherein the second voltage lags the first voltage in phase.
8 . The method of claim 1 , further comprising:
monitoring voltages in each of a plurality of resonant circuits, each resonant circuit including one of the plurality of charging coils; and
configuring a difference between the first electromagnetic flux and the second electromagnetic flux based on the voltages.
9 . The method of claim 8 , wherein configuring the difference between the first electromagnetic flux and the second electromagnetic flux comprises:
configuring a difference in magnitude between first electromagnetic flux and the second electromagnetic flux.
10 . The method of claim 8 , wherein configuring the difference between the first electromagnetic flux and the second electromagnetic flux comprises:
configuring a difference in phase between first electromagnetic flux and the second electromagnetic flux.
11 . A charging device, comprising:
a plurality of charging cells provided on a charging surface of the charging device; and
a controller configured to:
determine that a chargeable device is positioned proximate to the plurality of charging coils;
cause a first charging coil in the plurality of charging coils to produce a first electromagnetic flux; and
cause a second charging coil in the plurality of charging coils to produce a second electromagnetic flux, wherein the first electromagnetic flux has at least one characteristic that is different than a corresponding characteristic of the second electromagnetic flux.
12 . The charging device of claim 11 , wherein the at least one characteristic of the first electromagnetic flux includes a flux magnitude.
13 . The charging device of claim 11 , wherein the at least one characteristic of the first electromagnetic flux includes phase.
14 . The charging device of claim 11 , wherein the controller is configured to:
provide a first current to the first charging coil; and
provide a second current to the second charging coil, wherein the second current is greater in magnitude than the first current.
15 . The charging device of claim 11 , wherein the controller is configured to:
provide a first current to the first charging coil; and
provide a second current to the second charging coil, wherein the second current lags the first current in phase.
16 . The charging device of claim 11 , wherein the controller is configured to:
provide a first voltage to the first charging coil; and
provide a second voltage to the second charging coil, wherein the second voltage is greater than the first voltage.
17 . The charging device of claim 11 , wherein the controller is configured to:
provide a first voltage to the first charging coil; and
provide a second voltage to the second charging coil, wherein the second voltage lags the first voltage in phase.
18 . The charging device of claim 11 , wherein the controller is configured to:
monitor voltages in each of a plurality of resonant circuits, each resonant circuit including one of the plurality of charging coils; and
configure a difference between the first electromagnetic flux and the second electromagnetic flux based on the voltages.
19 . The charging device of claim 18 , wherein the controller is configured to:
configure a difference in magnitude between first electromagnetic flux and the second electromagnetic flux.
20 . The charging device of claim 18 , wherein the controller is configured to:
configure a difference in phase between first electromagnetic flux and the second electromagnetic flux.