METHODS AND DEVICES FOR INDUCTIVE COUPLING INTO POWER LINES

• US 20170331315A1
• Filed: 05/12/2016
• Published: 11/16/2017
• Est. Priority Date: 05/12/2016
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Condon, Kenneth, Fang, Xue Hai
• Granted Patent: US 10,038,333 B2
• Time in Patent Office: Days
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 50/001 Energy harvesting or scavenging
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence

Abstract

An electronic device is provided, including a housing having a back surface. The device includes a rechargeable battery, a capacitor, an inductor coil connected to the capacitor, the inductor coil being disposed around an axis oriented perpendicular to the back surface, a rectifier circuit connected to the inductor coil to output a direct current (DC), a DC-DC converter connected to the rectifier circuit, configured to trickle charge the battery with current received from the rectifier circuit, a test load switchably connected to the DC-DC converter, and a feedback circuit configured to detect a voltage level of the test load and provide an indication of the voltage level.

Claims

1. An electronic device including a housing having a back surface, comprising:

a rechargeable battery;

a capacitor;

an inductor coil connected to the capacitor, the inductor coil being disposed around an axis oriented perpendicular to the back surface;

a rectifier circuit connected to the inductor coil to output a direct current (DC);

a DC-DC converter connected to the rectifier circuit, configured to trickle charge the battery with current received from the rectifier circuit;

a test load switchably connected to the DC-DC converter; and

a feedback circuit configured to detect a voltage level of the test load and provide an indication of the voltage level.

2. The device of claim 1, wherein the inductor coil is integrated in the back surface.

3. The device of claim 1, wherein the capacitor is selected to tune the inductor coil to a resonant frequency of approximately 60 Hz.

4. The device of claim 1, further comprising:

a switch connected between the battery and the DC-DC converter, such that when the switch is moved to a first position the DC-DC converter is connected to the battery and when the switch is moved to a second position the DC-DC converter is disconnected from the battery and is connected to the test load.

5. The device of claim 1, further comprising:

a keypad input unit configured to receive input from a user;

a network interface unit configured to transmit a security signal to an external computing device based on a code entered in the keypad input unit,

wherein the keypad input unit and the network interface unit are powered by the battery.

6. The device of claim 1, further comprising:

a plurality of light emitting diodes disposed on the housing,

wherein the feedback circuit is configured to illuminate the plurality of light emitting diodes in varying colors based on the detected voltage level.

7. The device of claim 1, wherein the feedback circuit is configured to transmit an encoded signal to an external device, the encoded signal indicating the detected voltage level.

8. The device of claim 1, further comprising:

one or more temperature sensors positioned within the housing for measuring ambient temperature;

a user interface unit configured to receive input to control a heating, ventilation and air conditioning (HVAC) system;

a network interface unit configured to transmit a control signal encoding a system command to control the HVAC system based on the received input; and

a display unit configured to display information related to the HVAC system,

wherein the one or more temperature sensors, interface unit and display unit are powered by the battery.

9. The device of claim 1, further comprising:

an image sensing array configured to capture digital images;

a processor configured to drive the image sensing array; and

a memory configured to store images captured by the image sensing array,

wherein the image sensing array, the processor and the memory are powered by the battery.

10. The device of claim 1, further comprising:

a sensing circuit including an infrared sensor; and

a lens disposed to focus infrared energy onto the sensor,

wherein the sensing circuit is powered by the battery.

11. A method of inductive charging an electronic device using a powerline disposed in a premises, comprising:

detecting, with the electronic device, a magnetic field generated by current in the powerline within a wall of the premises at a first location;

determining a power generation level that the electronic device can achieve from inductive charging at the first location;

moving the electronic device to a second location;

providing, while the electronic device is moving, feedback indicating a level of power generation achievable via induction from the powerline;

attaching the electronic device to the wall at a position on the wall where the indicated level of power generation is above a threshold value; and

trickle-charging a rechargeable battery in the device using an inductive charging power circuit disposed in the electronic device.

12. The method of claim 11, wherein determining the power generation level comprises:

disconnecting the battery from the inductive charging power circuit;

connecting the inductive charging power circuit to a known load;

measuring a voltage across the load; and

determining the power generation level based on the voltage drop.

13. The method of claim 11, wherein providing the feedback indicating the level power generation comprises illuminating a plurality of light emitting diodes in varying colors, including a first color that indicates a low power generation level and a second color that indicates a high power generation level.

14. The method of claim 11, wherein providing feedback indicating the level of power generation comprises transmitting a digitally encoded signal to an external computing device, the digitally encoded signal indicating a value representing an amount of the generated power.

15. The method of claim 11, wherein providing feedback indicating the level of power generation comprises providing a range of audible sounds including a first audible sound that indicates a low power generation level and a second audible sound that indicates a high power generation level.