# US 10,483,804 B2 · Monotonic wireless power transfer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,483,804 B2 - Document ID: US10483804B2 - Status: Granted - Kind: B2 - Application number: 15/481,341 - Filed: 2017-04-06 - Published: 2017-12-07 - Granted: 2019-11-19 - Earliest claimed: 2016-06-07 - Assignees: Mediatek Inc. - Applicants: MediaTek Inc. - Inventors: Vladimir A. Muratov - Web page: https://patentgrep.com/patent/US10483804B2 ## CPC - H02J 50/12: of the resonant type - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract At least one component for a wireless power transmitter or a wireless power receiver. The at least one component includes a mechanical structure and/or circuitry configured to maintain and/or adjust a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant. ## Claims ### Claim 1 At least one component for a wireless power transmitter or a wireless power receiver, the at least one component comprising: a mechanical structure and/or circuitry configured to maintain and/or adjust a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant, wherein the constant is between 0.8 and 1.0, inclusive. ### Claim 2 (depends on 1) The at least one component of claim 1, wherein the at least component comprises circuitry configured to measure an electrical characteristic of the wireless power receiver and to adjust Q based on the electrical characteristic. ### Claim 3 (depends on 2) The at least one component of claim 2, wherein the circuitry comprises a current measurement device, a voltage measurement device, or both. ### Claim 4 (depends on 1) The at least one component of claim 1, wherein the at least one component comprises circuitry that is configured to adjust Q by adjusting a capacitance, inductance, equivalent resistance, and/or loading of the wireless power receiver. ### Claim 5 (depends on 4) The at least one component of claim 4, wherein the circuitry is configured to adjust the capacitance by controlling a variable capacitance of the wireless power receiver. ### Claim 6 (depends on 4) The at least one component of claim 4, wherein the circuitry is configured to adjust the inductance by controlling a variable inductance of the wireless power receiver. ### Claim 7 (depends on 4) The at least one component of claim 4, wherein the circuitry is configured to adjust the equivalent resistance by controlling a variable equivalent resistance of the wireless power receiver. ### Claim 8 (depends on 4) The at least one component of claim 4, wherein the circuitry is configured to adjust an operating frequency of the wireless power transmitter. ### Claim 9 (depends on 1) The at least one component of claim 1, wherein the mechanical structure and/or circuitry is configured to maintain and/or adjust K, Q or both such that a transfer function from the wireless power transmitter to the wireless power receiver is monotonic within a range of drive frequencies of the wireless power transmitter. ### Claim 10 (depends on 1) The at least one component of claim 1, wherein the at least one component comprises a mechanical structure configured to adjust K by setting or varying a distance between a transmit coil of the wireless power transmitter and a receive coil of the wireless power receiver. ### Claim 11 (depends on 1) A wireless power transmitter or a wireless power receiver comprising the at least one component of claim 1. ### Claim 12 A method of controlling a wireless power transmitter or a wireless power receiver, the method comprising: adjusting a coupling coefficient K between the wireless power transmitter and the wireless power receiver, a loaded quality factor Q of the wireless power receiver, or both, such that K times Q is less than a constant, wherein the constant is between 0.8 and 1.0, inclusive. ### Claim 13 (depends on 12) The method of claim 12, further comprising measuring an electrical characteristic of the wireless power receiver, wherein Q is adjusted based on the electrical characteristic. ### Claim 14 (depends on 13) The method of claim 13, wherein the electrical characteristic comprises a current measurement, a voltage measurement, an impedance measurement and/or a resistance measurement. ### Claim 15 (depends on 12) The method of claim 12, wherein Q is adjusted by adjusting a capacitance, inductance and/or equivalent resistance of the wireless power receiver. ### Claim 16 (depends on 15) The method of claim 15, wherein the capacitance is adjusted by controlling a variable capacitance of the wireless power receiver. ### Claim 17 (depends on 15) The method of claim 15, wherein the inductance is adjusted by controlling a variable inductance of the wireless power receiver. ### Claim 18 (depends on 15) The method of claim 15, wherein the equivalent resistance is adjusted by controlling a variable equivalent resistance of the wireless power receiver. ### Claim 19 (depends on 12) The method of claim 12, wherein K, Q or both are adjusted such that a transfer function from the wireless power transmitter to the wireless power receiver is monotonic within a range of drive frequencies of the wireless power transmitter. ### Claim 20 (depends on 12) The method of claim 12, wherein K is adjusted by setting or varying a distance between a transmit coil of the wireless power transmitter and a receive coil of the wireless power receiver. ### Claim 21 (depends on 12) The method of claim 12, wherein the adjusting comprises adjusting Q by adjusting a capacitance, inductance, equivalent resistance, and/or loading of the wireless power receiver. ### Claim 22 (depends on 21) The method of claim 21, comprising adjusting an operating frequency of the wireless power transmitter. ### Claim 23 A wireless power transfer system, comprising: a wireless power transmitter; and a wireless power receiver, wherein the wireless power transmitter, the wireless power receiver or both the wireless power transmitter and the wireless power receiver are configured to maintain a product of a coupling coefficient K between the wireless power transmitter and the wireless power receiver and a loaded quality factor Q of the wireless power receiver to be less than a constant, wherein the constant is between 0.8 and 1.0, inclusive.