# US 2014/0152114 A1 · Wireless power transmission system, wireless power receiving apparatus, and wireless power receiving method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0152114 A1 - Document ID: US20140152114A1 - Status: Published application - Kind: A1 - Application number: 13/723,821 - Filed: 2012-12-21 - Published: 2014-06-05 - Earliest claimed: 2012-12-03 - Assignees: Ls Cable & System Ltd. - Inventors: Young Sun KIM; Un Kyu Park; Sung Han You; Min Seok Han - Web page: https://patentgrep.com/patent/US20140152114A1 ## CPC - H04B 5/79: for data transfer in combination with power transfer - B60L 53/12: Inductive energy transfer - H02J 7/04: Regulation of charging current or voltage - H02J 7/96: in response to battery voltage - H02J 50/12: of the resonant type - H04B 5/266: {One coil at each side, e.g. with primary and secondary coils} - H02H 9/041: {using a short-circuiting device} - H02J 50/10: using inductive coupling - H02J 50/80: involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices - 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 90/14: Plug-in electric vehicles - H04B: TRANSMISSION - 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 - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Disclosed are a wireless power receiving apparatus, a wireless power transmission system, and a wireless power receiving method. The wireless power receiving apparatus includes a power receiving coil for receiving a power signal wirelessly transmitted, a rectifier circuit for rectifying the power signal into direct current (DC) output power, a switching unit for controlling input of the power signal to the rectifier circuit at an rear end of the power receiving coil, and a control unit for measuring a voltage of the DC output voltage, comparing the voltage with a predetermined allowable voltage, and controlling an operation of the switching unit. ## Claims ### Claim 1 A wireless power receiving apparatus comprising: a power receiving coil for receiving a power signal wirelessly transmitted; a rectifier circuit for rectifying the power signal into direct current (DC) output power; a switching unit for controlling input of the power signal to the rectifier circuit at an rear end of the power receiving coil; and a control unit for measuring a voltage of the DC output power, comparing the voltage with a predetermined allowable voltage, and controlling an operation of the switching unit. ### Claim 2 (depends on 1) The wireless power receiving apparatus according to claim 1, wherein the control unit adjusts received power by feedback controlling a voltage of the power signal with a duty ratio about periods of time that the switching unit is turned on and off when the measured voltage exceeds the allowable voltage. ### Claim 3 (depends on 1) The wireless power receiving apparatus according to claim 1, wherein the switching unit is disposed between both ends of the power receiving coil or a matching circuit or is disposed on a path between the power receiving coil and the rectifier circuit. ### Claim 4 (depends on 1) The wireless power receiving apparatus according to claim 1, wherein the control unit selects a duty ratio set for each respective voltage level in a circuit operating voltage table, based on the measured voltage, and controls the switching unit with the duty ratio. ### Claim 5 (depends on 1) The wireless power receiving apparatus according to claim 1, wherein the switching unit controls supply of the DC output power to a battery between the rectifier circuit and the battery. ### Claim 6 (depends on 1) The wireless power receiving apparatus according to claim 1, wherein the power receiving coil and a power transmitting coil of a wireless power transmitting apparatus are magnetically coupled to each other to transmit the power signal using a magnetic induction method or a magnetic resonance method. ### Claim 7 (depends on 1) The wireless power receiving apparatus according to claim 1, further comprising a matching circuit disposed between the power receiving coil and the rectifier circuit and comprising at least one of a serial resonance circuit and a parallel resonance circuit. ### Claim 8 A wireless power transmission system comprising: a wireless power transmitting apparatus for transmitting a power signal to a power transmitting coil to generate a magnetic field around the power transmitting coil; and one or more wireless power receiving apparatuses coupled to the magnetic field, for wirelessly receiving the power signal, wherein the wireless power receiving apparatuses measure a change in a voltage of the power signal and control received power, based on the measurement result. ### Claim 9 (depends on 8) The wireless power transmission system according to claim 8, wherein each of the wireless power receiving apparatuses comprises: a power receiving coil magnetically coupled to the power transmitting coil, for receiving the power signal; a rectifier circuit for rectifying the power signal into direct current (DC) output power; a switching unit for controlling input of the power signal to the recifier circuit at a rear end of the power receiving coil or on a path between the power receiving coil and the rectifier circuit; and a control unit for measuring a voltage of the DC output power, comparing the voltage with a predetermined allowable voltage, and controlling an operation of the switching unit. ### Claim 10 (depends on 9) The wireless power transmission system according to claim 9, wherein the control unit adjusts received power by feedback controlling the voltage of the power signal with a duty ratio about periods of time that the switching unit is turned on and off when the measured voltage exceeds the allowable voltage. ### Claim 11 (depends on 9) The wireless power transmission system according to claim 9, wherein the control unit selects a duty ratio set for each respective voltage level in a circuit operating voltage table, based on the measured voltage, and controls the switching unit with the duty ratio. ### Claim 12 (depends on 9) The wireless power transmission system according to claim 9, wherein the power receiving coil and the power transmitting coil are magnetically coupled to each other to transmit the power signal using a magnetic induction method or a magnetic resonance method. ### Claim 13 (depends on 9) The wireless power transmission system according to claim 9, wherein the each of the wireless power receiving apparatuses further comprises a matching circuit disposed between the power receiving coil and the rectifier circuit and comprising at least one of a serial resonance circuit and a parallel resonance circuit. ### Claim 14 A wireless power receiving method of a wireless power receiving apparatus, the method comprising: receiving a power signal wirelessly via magnetic resonance coupling at a power receiving circuit; connecting the power receiving coil and an internal circuit to each other through a switching unit; measuring a voltage induced in the internal circuit by the power signal; and controlling the switching unit so as to maintain the measured voltage within an operating voltage range of the internal circuit. ### Claim 15 (depends on 14) The method of claim 14, further comprising predetermining at least one of the operating voltage range of the internal circuit and a maximum allowable voltage, prior to the receiving the power signal. ### Claim 16 (depends on 15) The method of claim 15, wherein the controlling the switching unit comprises controlling the operation of the switching unit with a predetermined duty ratio to reduce the voltage induced in the internal circuit when the measured voltage is equal to or greater than the maximum allowable voltage. ### Claim 17 (depends on 14) The method of claim 14, wherein the controlling the switching unit comprises selecting a duty ratio set for each respective level in a circuit operating voltage table based on the measured voltage, and controlling the operation of the switching unit with the duty ratio.