Foreign-object detection for resonant wireless power system

• US 9,837,848 B2
• Filed: 03/14/2014
• Issued: 12/05/2017
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Original Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Inventors: Fisher-Jeffes, Timothy Perrin, Plumb, William, Riehl, Patrick Stanley, Satyamoorthy, Anand
• Primary Examiner(s): Alam, Mohammed
• Application Number:
  US14/771,568
• Publication Number:
  US 20160028268A1
• Time in Patent Office: 1,362 Days
• Field of Search: 320108
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment

Abstract

A wireless charging system is provided that includes a charger portion that receives one or more portable elements for charging wirelessly. The charger portion controls the amount of power needed to charge the one or more portable elements. An inband communication module receives inband communications with the one or more portable elements using a random access mode. The charger portion utilizes the inband communications to determine how much power is needed, via energy based reporting, to charge the one or more portable elements that avoids conveying identification information.

Claims

1. A wireless charging apparatus comprising:

a charger portion configured to wirelessly charge one or more portable devices, the charger portion being configured to control an amount of power provided to charge the one or more portable devices; and

an communication module configured to receive communications from the one or more portable devices using a random access mode, wherein the communications from the one or more portable devices using the random access mode are unsynchronized and do not include identification information of the one or more portable devices,

wherein the charger portion is configured to receive energy information from the one or more portable devices identifying an amount of energy transferred to the one or more portable devices, and to determine how much power is needed to charge the one or more portable devices using the energy information.

2. The wireless charging apparatus of claim 1, wherein the charger portion is configured to operate in a plurality of processing stages for power management.

3. The wireless charging apparatus of claim 2, wherein the processing stages comprise a standby stage that powers up the charger portion for detecting one of the one or more portable devices.

4. The wireless charging apparatus of claim 2, wherein the processing stages comprise a power stage that listens for messages from one or more unregistered portable devices and detects fault conditions.

5. The wireless charging apparatus of claim 4, wherein the processing stages comprise a faulting handling stage that handles the fault conditions received from the power stage.

6. A method of performing wireless charging of one or more portable devices by a charger portion configured to control an amount of power provided to charge the one or more portable devices, the method comprising:

receiving, by an communication module of the charger portion, communications from the one or more portable devices using a random access mode,

wherein the charger portion is configured to utilize the communications to determine how much power is needed to charge the one or more portable devices,

wherein the communications from the one or more portable devices using the random access mode are unsynchronized, do not convey identification information, and comprise one or more reports of the energy received by the one or more portable devices.

7. The method of claim 6, wherein the charger portion is configured to operate in a plurality of processing stages for power management.

8. The method of claim 7, wherein the processing stages comprise a standby stage that powers up the charger portion for detecting one of the one or more portable devices.

9. The method of claim 7, wherein the processing stages comprise a power stage that listens for messages from one or more unregistered portable devices and detects fault conditions.

10. The method of claim 9, wherein the processing stages comprise a faulting handling stage that handles the fault conditions received from the power stage.