Monitoring for Foreign Bodies During Inductive Charging

• US 20160009186A1
• Filed: 02/06/2015
• Published: 01/14/2016
• Est. Priority Date: 08/07/2012
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: GOETHEL, Joachim
• Granted Patent: US 9,676,286 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/124 Detection or removal of foreign bodies
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A device having a charging unit and being configured for inductive power transmission from the charging unit to a vehicle, in which the charging unit comprises a primary coil and the vehicle comprises a secondary coil and in which the primary coil generates a magnetic transmission field in a transmission range between the primary coil and the secondary coil, wherein the vehicle has a sensor unit for temperature monitoring in the transmission range, the charging unit comprises a control unit and in a charging operation the transmission power can be controlled by the control unit as a function of a result of temperature monitoring.

Claims

1. A device having a charging unit and being configured for inductive power transmission from the charging unit to a vehicle, wherein the charging unit comprises a primary coil and the vehicle comprises a secondary coil and in which the primary coil generates a magnetic transmission field in a transmission range between the primary coil and the secondary coil, wherein

the vehicle comprises a sensor unit for temperature monitoring in the transmission range,

the charging unit comprises a control device, and

the transmission power can be controlled by the control device during a charging operation as a function of a result of said temperature monitoring.

2. The device according to claim 1, wherein

the sensor unit is designed as an infrared detector system,

the infrared detector system has a thermal resolution limit,

the infrared detector system has a spatial resolution limit,

an object having thermal properties above the thermal resolution limit and spatial properties above the spatial resolution limit is designated as a critical object and

a critical object situated in the transmission range can be detected by the infrared detector system.

3. The device according to claim 2, wherein

the transmission power in a charging operation can be adjusted by the control unit at a first rate of power increase,

in a charging operation the transmission power can be adjusted by the control unit at a second rate of power increase, and

the second rate of power increase is greater than the first rate of power increase.

4. The device according to claim 3, wherein

at the first rate of power increase, a standard object situated in the transmission range can be heated by the transmission field over a critical period of time,

within the critical period of time, the standard object becomes a critical object and

the power increase in the transmission range can be interrupted by the control unit after detection of the standard object by the infrared detector system and/or the transmission power can be reduced by the control unit.

5. A method for a charging operation using a device according to claim 4, wherein the method comprises the acts of:

increasing the transmission power, by the control unit, at the first rate of power increase during the critical period of time;

increasing the transmission power, by the control unit, at the second rate of power increase after the critical period of time; and

interrupting the power increase in the transmission range by the control unit and/or by reducing the transmission power by the control unit after detection of a critical object by the infrared detector system during the critical period of time or after the critical period of time.