# US 11,027,619 B2 · Charging station, motor vehicle and method for inductive charging of a battery of a motor vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,027,619 B2 - Document ID: US11027619B2 - Status: Granted - Kind: B2 - Application number: 16/323,852 - Filed: 2017-08-03 - Published: 2019-06-06 - Granted: 2021-06-08 - Earliest claimed: 2016-09-07 - Assignees: Audi AG - Applicants: Audi AG - Inventors: Stefan Maiwald; Johann Schneider - Web page: https://patentgrep.com/patent/US11027619B2 ## CPC - B60L 53/124: Detection or removal of foreign bodies - B60L 53/122: Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil - H01F 38/14: Inductive couplings - H02J 50/12: of the resonant type - H02J 50/60: responsive to the presence of foreign objects, e.g. detection of living beings - 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 - 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 - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A charging station for the inductive charging of a battery of a motor vehicle. A primary resonant circuit for generating an electrical oscillation, the primary resonant circuit has a primary capacitor and a primary coil. The charging station includes a measuring device designed to excite the primary resonant circuit up to a predefinable voltage amplitude, then to interrupt the excitation of the primary resonant circuit and to evaluate the time function of the voltage amplitude of the primary resonant circuit after the interruption of the excitation of the primary resonant circuit. ## Claims ### Claim 1 A charging station for the inductive charging of a battery of a motor vehicle, comprising: a primary resonant circuit for generating an electrical oscillation, wherein the primary resonant circuit has a rectifier, a primary capacitor, and a primary coil, wherein the charging station includes a measuring device designed to: excite the primary resonant circuit up to a predefinable voltage amplitude; then to interrupt the excitation of the primary resonant circuit; and to evaluate a time function of the voltage amplitude of the primary resonant circuit after the interruption of the excitation of the primary resonant circuit, wherein the measuring device is designed to determine whether the rectifier is blocking, and the measuring device is further designed to evaluate the time function of the voltage amplitude of the primary resonant circuit only when the rectifier is blocking. ### Claim 2 (depends on 1) The charging station as claimed in claim 1, wherein the measuring device is designed to interrupt the primary resonant circuit in a first step and to short-circuit the primary resonant circuit in a second step. ### Claim 3 (depends on 1) The charging station as claimed in claim 1, wherein the measuring device is designed to determine a predefinable parameter in order to evaluate the time function of the voltage amplitude of the primary resonant circuit after the interruption of the excitation and the short-circuiting of the primary resonant circuit, including: the voltage amplitude after a predefinable time; the length of time until a second predefinable voltage amplitude is measurable; and/or a damping rate of the voltage amplitudes. ### Claim 4 (depends on 3) The charging station as claimed in claim 3, wherein the measuring device is furthermore designed to compare the parameter determined during the evaluation of the time function of the voltage amplitude of the primary resonant circuit after the interruption of the excitation of the primary resonant circuit against a reference value and to put out information in dependence on the comparison as to whether the inductive charging is enabled or not. ### Claim 5 (depends on 1) The charging station as claimed in claim 1, wherein the measuring device is coupled to a connection between the primary capacitor and the primary coil, across a shunt resistor or a voltage divider. ### Claim 6 (depends on 1) The charging station as claimed in claim 1, wherein the primary resonant circuit is constructed as a full bridge circuit, while the measuring device is designed to interrupt the excitation of the primary resonant circuit and to short-circuit the full bridge circuit, by conductive switching of two low-lying switches of the full bridge circuit. ### Claim 7 A motor vehicle, comprising: a charging device for inductive charging of a battery of the motor vehicle, wherein the charging device has a secondary resonant circuit having a secondary capacitor and a secondary coil, wherein a rectifier is connected between the secondary resonant circuit and the battery of the motor vehicle, wherein the charging device furthermore includes a measuring device designed to evaluate the time function of the voltage amplitude of the secondary resonant circuit after an interruption of the excitation of the secondary resonant circuit, wherein the measuring device is designed to determine whether the rectifier is blocking, and the measuring device is further designed to evaluate the time function of the voltage amplitude of the secondary resonant circuit only when the rectifier is blocking. ### Claim 8 A method for inductive charging of a battery of a motor vehicle by a charging station, having a primary resonant circuit with a primary capacitor and a primary coil for generating an electrical oscillation, wherein the motor vehicle has a secondary resonant circuit with a secondary capacitor and a secondary coil, wherein a rectifier is connected between the secondary resonant circuit and the battery of the motor vehicle, comprising: a) excite the primary resonant circuit up to a predefinable voltage amplitude; b) interrupt the excitation of the primary resonant circuit; and c) evaluate the time function of a decaying voltage amplitude by a measuring device after the interruption of the excitation of the primary resonant circuit, wherein the measuring device is designed to determine whether the rectifier is blocking, and the measuring device is further designed to evaluate the time function of the voltage amplitude of the primary resonant circuit only when the rectifier is blocking. ### Claim 9 (depends on 8) The method as claimed in claim 8, wherein in step a) the predefinable voltage amplitude is dimensioned such that the rectifier of the motor vehicle is blocking. ### Claim 10 (depends on 8) The method as claimed in claim 8, wherein in step a) the primary resonant circuit is excited to its rated voltage. ### Claim 11 (depends on 8) The method as claimed in claim 8, wherein step c) is performed in the charging station and/or in the motor vehicle.