OPEN-CIRCUIT IMPEDANCE CONTROL OF A RESONANT WIRELESS POWER RECEIVER FOR VOLTAGE LIMITING

• US 20140246923A1
• Filed: 09/27/2013
• Published: 09/04/2014
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Original Assignee: MediaTek Singapore Pte. Ltd. (MediaTek, Inc.)
• Inventors: Riehl, Patrick Stanley, Satyamoorthy, Anand, Akram, Hasnain
• Granted Patent: US 10,014,724 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H02J 50/12 of the resonant type

Abstract

A resonant wireless power (RWP) receiver is provided that includes an inductor element that couples with a resonant wireless power source. A capacitor arrangement is coupled to the inductor element altering the open-circuit impedance of the RWP receiver to reduce the ac voltage under certain defined situations. The capacitor arrangement includes a plurality capacitors tuned to a control ac voltage in the RWP receiver.

Claims

1. A resonant wireless power (RWP) receiver comprising:

an inductor element that couples with a resonant wireless power source; and

a capacitor arrangement coupled to the inductor element altering the open-circuit impedance of the RWP receiver to reduce the ac voltage under certain defined situations, the capacitor arrangement includes a plurality of capacitors tuned to control the ac voltage in the RWP receiver.

2. The RWP receiver of claim 1, wherein the capacitor arrangement comprises a series-parallel circuit having an capacitor that can be switched in to adjust the open-source impedance Zoc.

3. The RWP receiver of claim 1, wherein the capacitor arrangement comprises a parallel-series circuit with a Zoc-adjustment capacitor.

4. The RWP receiver of claim 1 further comprising a rectifier.

5. The RWP receiver of claim 4, wherein the capacitor arrangement comprises one or more Zoc-adjustment capacitors switched to ground.

6. The RWP receiver of claim 1, wherein the capacitor arrangement utilizes one or more switches to the ac voltage.

7. The RWP receiver of claim 1, wherein the rectifier comprises a synchronous rectifier or diode rectifier.

8. A resonant wireless power (RWP) system comprising:

a source circuit that includes a reflected impedance in series with a source coil; and

a receiver circuit that is coupled to the source circuit using an inductor element, and includes a capacitor arrangement coupled to the inductor element altering the open-circuit impedance of the receiver circuit to reduce the ac voltage under certain defined situations, the capacitor arrangement includes a plurality of capacitors tuned to control the ac voltage in the receiver circuit.

9. The RWP system of claim 8, wherein the capacitor arrangement comprises a series-parallel circuit having a capacitor that can be switched in to adjust the open-source impedance Zoc.

10. The RWP system of claim 8, wherein the capacitor arrangement comprises a parallel-series circuit with a Zoc-adjustment capacitor.

11. The RWP system of claim 8 further comprising a rectifier.

12. The RWP system of claim 11, wherein the capacitor arrangement comprises one or more Zoc-adjustment capacitors switched to ground.

13. The RWP system of claim 8, wherein the capacitor arrangement utilizes one or more switches to the ac voltage.

14. The RWP system of claim 8, wherein the rectifier comprises a synchronous rectifier or diode rectifier.