# US 12,603,524 B2 · Power transmitter protection for receiver fault in a wireless power system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,603,524 B2 - Document ID: US12603524B2 - Status: Granted - Kind: B2 - Application number: 18/292,648 - Filed: 2022-09-08 - Published: 2024-10-17 - Granted: 2026-04-14 - Earliest claimed: 2021-09-09 - Assignees: GE Intellectual Property Licensing, LLC - Applicants: GE Intellectual Property Licensing, LLC - Inventors: Jayanti Ganesh; Viswanathan Kanakasabai; Subbarao Tatikonda - Web page: https://patentgrep.com/patent/US12603524B2 ## CPC - H02J 50/12: of the resonant type - H02J 7/60: including safety or protection arrangements - H02J 7/80: including monitoring or indicating arrangements - H02J 50/80: involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices - H02M 1/32: Means for protecting converters other than automatic disconnection - H02M 3/33523: {with galvanic isolation between input and output of both the power stage and the feedback loop} - H02M 3/33571: {Half-bridge at primary side of an isolation transformer} - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) ## Abstract This disclosure provides systems, methods and apparatuses for a wireless power transmission apparatus to detect a fault of the wireless power reception apparatus. Various implementations relate generally to fault detection and mitigation in a wireless power system. In some aspects, a transmission (TX) controller of the wireless power transmission apparatus can detect a fault in the wireless power reception apparatus based on power transfer measurements or calculations in the wireless power transmission apparatus. The techniques may enable the wireless power transmission apparatus to detect faults such as an open circuit in the wireless power reception apparatus or a thermostat failure, among other examples. During the transmission of wireless power, the wireless power transmission apparatus may detect the fault and cease the transmission of wireless power. ## Claims ### Claim 1 A method performed by a Power Transmitter, comprising: generating power for transmission from the Power Transmitter to a Power Receiver; obtaining transmitter power measurements at an output of an inverter of the Power Transmitter during a power transfer period; calculating a transmitter power based on an average of the transmitter power measurements; calculating a power transfer amount for the power transfer period based, at least in part, on a difference between the transmitter power and an expected power transmission loss associated with the Power Transmitter; and protecting, by the Power Transmitter, against a fault of the Power Receiver when the power transfer amount is below a threshold during a power transfer phase. ### Claim 2 (depends on 1) The method of claim 1, further comprising: calculating a plurality of power transfer amounts including at least a first power transfer amount during a first power transfer period of a plurality of power transfer periods; and detecting the fault when at least the first power transfer amount is below the threshold. ### Claim 3 (depends on 2) The method of claim 2, further comprising: changing an operating point of the Power Transmitter for a second power transfer period of the plurality of power transfer periods; calculating a second power transfer amount of the plurality of power transfer amounts during the second power transfer period; and detecting the fault when both the first power transfer amount and the second power transfer amount is below the threshold. ### Claim 4 (depends on 3) The method of claim 3, wherein the operating point is an operating frequency of the power generated by the Power Transmitter, the method further comprising: generating the power at a first operating frequency during the first power transfer period; and generating the power at a second operating frequency during the second power transfer period. ### Claim 5 (depends on 1) The method of claim 1, further comprising: changing an operating point of the Power Transmitter for each of a plurality of power transfer periods; determining a plurality of power transfer amounts corresponding to the plurality of power transfer periods based on measurements of voltage and current of the power generated at the Power Transmitter; and detecting the fault based on the plurality of power transfer amounts being below the threshold. ### Claim 6 (depends on 5) The method of claim 5, further comprising: detecting the fault after a fault detection time period during which the plurality power transfer amounts remain below the threshold. ### Claim 7 (depends on 5) The method of claim 5, further comprising: detecting the fault after a threshold quantity of the plurality power transfer amounts are below the threshold during the power transfer phase. ### Claim 8 (depends on 1) The method of claim 1, wherein protecting against the fault includes ceasing transmission of power from the Power Transmitter. ### Claim 9 (depends on 1) The method of claim 1, wherein protecting against the fault includes communicating a fault detection message to the Power Receiver to indicate that the Power Transmitter has detected the fault. ### Claim 10 (depends on 1) The method of claim 1, wherein obtaining transmitter power measurements includes: measuring voltage and current at the inverter of the Power Transmitter during the power transfer period; and multiplying the measured voltage and current to obtain the transmitter power measurements; and wherein calculating the one or more power transfer amounts includes averaging the transmitter power measurements to calculate the transmitter power associated with the power transfer period. ### Claim 11 (depends on 1) The method of claim 1, wherein the power transfer period includes one or more half cycles of an alternating current (AC) power supply coupled to the power transmitter. ### Claim 12 (depends on 1) The method of claim 1, further comprising: detecting the fault of the Power Receiver regardless of whether the Power Transmitter receives power control messages from the Power Receiver. ### Claim 13 (depends on 1) The method of claim 1, further comprising: setting the threshold based on at least one member selected from a group consisting of: a pre-determined fault detection threshold; a factor based on one or more power transfer amounts; a factor based on a measured current associated with a primary coil of the Power Transmitter; and a configurable offset value. ### Claim 14 (depends on 1) The method of claim 1, further comprising: detecting the fault when any one of the-measurements of the Power Transmitter indicate a current that is above an overcurrent threshold. ### Claim 15 A Power Transmitter, comprising: a power transmitter circuit including an inverter and a primary coil to generate power for transmission from the Power Transmitter to a Power Receiver; and a transmission controller configured to: obtain transmitter power measurements at an output of the inverter during a power transfer period, calculate a transmitter power based on an average of the transmitter power measurements, calculate a power transfer amount for the power transfer period based, at least in part, on a difference between the transmitter power and an expected power transmission loss associated with the Power Transmitter, and protect against a fault of the Power Receiver when the power transfer amount is below a threshold during a power transfer phase. ### Claim 16 (depends on 15) The Power Transmitter of claim 15, wherein the transmission controller is configured to: calculate a plurality of power transfer amounts including at least a first power transfer amount during a first power transfer period of a plurality of power transfer periods; and detect the fault when at least the first power transfer amount is below the threshold. ### Claim 17 (depends on 16) The Power Transmitter of claim 16, wherein the transmission controller is configured to: change an operating point of the power transmitter circuit for a second power transfer period of the plurality of power transfer periods; calculate a second power transfer amount of the plurality of power transfer amounts during the second power transfer period; and detect the fault when both the first power transfer amount and the second power transfer amount is below the threshold. ### Claim 18 (depends on 17) The Power Transmitter of claim 17, wherein the operating point is an operating frequency of the power generated by the power transmitter circuit, and wherein the transmission controller is configured to: cause the power transmitter circuit to generate the power at a first operating frequency during the first power transfer period; and cause the power transmitter circuit to generate the power at a second operating frequency during the second power transfer period. ### Claim 19 (depends on 15) The Power Transmitter of claim 15, wherein the transmission controller is configured to: change an operating point of the power transmitter circuit for each of a plurality of power transfer periods; determine a plurality of power transfer amounts corresponding to the plurality of power transfer periods based on measurements of voltage and current at an inverter of the power transmitter circuit; and detect the fault based on the plurality of power transfer amounts being below the threshold. ### Claim 20 (depends on 19) The Power Transmitter of claim 19, wherein the transmission controller is configured to: detect the fault after a fault detection time period during which the plurality power transfer amounts remain below the threshold or after a threshold quantity of the plurality power transfer amounts are below the threshold during the power transfer phase. ### Claim 21 (depends on 15) The Power Transmitter of claim 15, wherein the transmission controller is configured to protect against the fault by causing the power transmitter circuit to cease generation of the power. ### Claim 22 (depends on 15) The Power Transmitter of claim 15, further comprising: a communication unit configured to communicate a fault detection message to the Power Receiver to indicate that the transmission controller has detected the fault. ### Claim 23 (depends on 15) The Power Transmitter of claim 15, further comprising: a voltage sensor and a current sensor coupled to the inverter and configured to measure voltage and current, respectively, associated with the output of the inverter, wherein the transmission controller is configured to: multiply the measured voltage and current to obtain the transmitter power measurements, and average the transmitter power measurements to calculate the transmitter power associated with the power transfer period. ### Claim 24 (depends on 15) The Power Transmitter of claim 15, wherein the power transfer period includes one or more half cycles of an alternating current (AC) power supply coupled to the power transmitter. ### Claim 25 (depends on 15) The Power Transmitter of claim 15, further comprising: a communication unit, wherein the transmission controller is configured to detect the fault regardless of whether the communication unit receives messages from the Power Receiver. ### Claim 26 (depends on 1) The method of claim 1, wherein the fault includes an open circuit as a result of at least one of: a blown fuse in the Power Receiver, a failure of a heating element, thermal fuse, or a disconnect switch of the Power Receiver, an open relay contact in the Power Receiver, an open diode in a converter of the Power Receiver.