# US 11,309,746 B2 · Wireless power transfer device with foreign object detection, system, and method for performing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,746 B2 - Document ID: US11309746B2 - Status: Granted - Kind: B2 - Application number: 16/707,439 - Filed: 2019-12-09 - Published: 2020-04-16 - Granted: 2022-04-19 - Earliest claimed: 2012-06-22 - Assignees: Sony Group Corporation - Applicants: Sony Group Corporation - Inventors: Hiroaki Nakano; Osamu Kozakai; Shinji Komiyama; Kenichi Fujimaki - Web page: https://patentgrep.com/patent/US11309746B2 ## CPC - H02J 50/60: responsive to the presence of foreign objects, e.g. detection of living beings - H02J 50/12: of the resonant type - H02J 50/80: involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices - B60L 2240/36: Temperature of vehicle components or parts - Y02T 10/70: Energy storage systems for electromobility, e.g. batteries - Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors - Y02T 90/12: Electric charging stations - Y02T 90/14: Plug-in electric vehicles - Y02T 90/16: Information or communication technologies improving the operation of electric vehicles - Y04S 30/14: Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION - Y04S: SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS ## Abstract Methods and apparatus for detecting the presence of undesirable foreign matter in a region between a wireless power transmission apparatus and a power reception apparatus are described. First and second detection methods, based on different detection schemes, may be used to detect and distinguish the presence of foreign matter from misalignment during power transfer operation. A first detection method may be used before power is transferred to a load in a power reception apparatus, and a second detection method may be used while power is supplied to the load. ## Claims ### Claim 1 A power receiving apparatus comprising: a power reception coil configured to wirelessly receive a transmitted power from a power transmission apparatus; a battery that is chargeable by the transmitted power; memory configured to store, prior to receipt of the transmitted power by the power reception coil, a Q-value of the power receiving apparatus that is measured when it is ensured no foreign matter is near the power receiving apparatus, and a controller configured to stop supplying power to a load in a case where foreign matter is detected near the power receiving apparatus. ### Claim 2 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is configured to send the Q-value to the power transmission apparatus before the power reception coil receives the transmitted power. ### Claim 3 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is configured to send the Q-value to the power transmission apparatus before the transmitted power is supplied to the battery. ### Claim 4 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is configured to obtain a value of DC power of the transmitted power while the transmitted power is supplied to the battery. ### Claim 5 (depends on 4) The power receiving apparatus of claim 4, wherein the power receiving apparatus is configured to obtain, from the power transmission apparatus, the value of the DC power of the transmitted power. ### Claim 6 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is configured to store a frequency with which the Q-value is obtained. ### Claim 7 (depends on 1) The power receiving apparatus of claim 1, wherein the Q-value is sent, using a load modulation, to the power transmission apparatus. ### Claim 8 (depends on 1) The power receiving apparatus of claim 1, further comprising: a processing device configured to: detect a frequency at which the Q-value is obtained as a resonant frequency, and transmit, using a load modulation, the detected resonant frequency to the power transmission device. ### Claim 9 (depends on 1) The power receiving apparatus of claim 1, wherein the Q-value is influenced by a metal contained in the power reception apparatus. ### Claim 10 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is configured to send a notification to the power transmission apparatus when the foreign matter is detected between the power transmission apparatus and the power receiving apparatus. ### Claim 11 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is configured to notify a user to remove the foreign matter when the foreign matter is detected between the power transmission apparatus and the power receiving apparatus. ### Claim 12 (depends on 1) The power receiving apparatus of claim 1, further comprising: a control unit configured to notify a user when a charging is completed. ### Claim 13 (depends on 1) The power receiving apparatus of claim 1, wherein the power receiving apparatus is an electric vehicle, a home electronic appliance, a mobile phone, or a television receiver.