CHECKING A PRESENCE OF AN ELECTRICALLY CONDUCTIVE BODY

• US 20170012674A1
• Filed: 07/05/2016
• Published: 01/12/2017
• Est. Priority Date: 07/10/2015
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Huber, Klaus, Seisenberger, Claus
• Granted Patent: US 10,938,445 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 2270/147 electro magnetic [EMI]
• CPC Class Codes: B60L 53/124 Detection or removal of foreign bodies
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: B60L 53/60 Monitoring or controlling charging stations
• CPC Class Codes: G01V 3/10 using induction coils
• CPC Class Codes: G01V 3/104 using several coupled or uncoupled coils G01V3/101 takes precedence
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• 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
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

An apparatus checks for a presence of an electrically conductive body in the near field of charging coils of an arrangement for induced charging. At least one transmitting device provides a transmission signal in the form of a magnetic field. At least one receiving device generates a reception signal from the transmission signal and induced into the receiving device. The transmitting device and the receiving device are formed in such a way that, when the electrically conductive body is present, a first reception signal forms and, when the electrically conductive body is absent, a second reception signal, different than the first, forms in the receiving device on account of the induced transmission signal. The transmitting device and the receiving device are formed in a manner dependent on the magnetic field of the charging coils in such a way that, when the electrically conductive body is absent, partial reception signals form in the receiving device on account of the induced transmission signal, where partial reception signals substantially cancel one another out in the reception signal.

Claims

1. An apparatus for checking a presence of an electrically conductive body in a near field of charging coils of an arrangement for induced charging, the apparatus comprising:

at least one transmitting device for providing a transmission signal in the form of a magnetic field, and

at least one receiving device for generating a first reception signal from the transmission signal provided by the transmitting device and induced into the receiving device,

wherein the transmitting device and the receiving device are formed in such a way that, when the electrically conductive body is present, a first reception signal forms and, when the electrically conductive body is absent, a second reception signal, different than the first reception signal, forms in the receiving device on account of the induced transmission signal, and

wherein the transmitting device and the receiving device are formed in a manner dependent on the magnetic power field of the charging coils in such a way that, when the electrically conductive body is absent, the second reception signal comprises partial reception signals formed in the receiving device on account of the induced transmission signal, the partial reception signals substantially cancelling one another out in the second reception signal.

2. The apparatus as claimed in claim 1, wherein the transmitting device and the receiving device each have a form of a conductor loop twisted at least once.

3. The apparatus as claimed in claim 1, wherein the partial reception signals are canceled out in the second reception signal in such a way that a geometrical arrangement of the transmitting device, the geometrical arrangement of the receiving device, or the geometrical arrangements of the transmit and receiving devices are determined in a manner dependent on a symmetry property of the magnetic power field of the charging coils.

4. The apparatus as claimed in claim 1, wherein, given a point symmetry of a z-component of the magnetic field in relation to a point of intersection of a y-axis (y) and a x-axis (x) of the charging coils mounted in the x-y plane of the transmitting device and receiving device,

a) first conductor loops of the transmitting device are arranged geometrically in such a way that the first conductor loops are located on the y-axis (y) of the magnetic field in such a way that an opening, enclosed by the first conductor loops, is incident on the y-axis,

b) second conductor loops of the receiving device are arranged geometrically in such a way that the second conductor loops are located on the x-axis (x) of the magnetic field in such a way that a crossover point formed by the second conductors is incident on the x-axis.

5. The apparatus as claimed in claim 1, wherein the charging coils are a double-D coil system, wherein primary coils of the double-D coil system are arranged in an x-y plane axially symmetrically with respect to a y-axis.

6. The apparatus as claimed in claim 1, wherein, given an axial symmetry of a z-component of the magnetic field in relation to a x-axis and/or y-axis of the charging coils mounted in the x-y plane of the transmitting device and receiving device,

a) first conductor loops of the transmitting device are arranged geometrically in such a way that the first conductor loops are located on the y-axis of the magnetic field in such a way that a crossover point formed by first twisted conductors is incident on the y-axis,

b) second conductor loops of the receiving device are arranged geometrically in such a way that the second conductor loops are located on the x-axis of the magnetic field in such a way that a crossover point formed by the second twisted conductors is incident on the x-axis.

7. The apparatus as claimed in claim 1, wherein the charging coils are a circular coil system, wherein a primary coil of the circular coil system is located on a point of intersection of an x-axis and an y-axis of an x-y plane.

8. The apparatus as claimed in claim 1, wherein the receiving device comprises a predetermined number of receiving coils arranged with respect to the transmitting device in such a way that the transmission signal is induced into the respective receiving coils substantially in identical portions.

9. The apparatus as claimed in claim 1, wherein receiving coils of the receiving device are arranged alongside one another in a main extension direction of the receiving device.

10. The apparatus as claimed in claim 1, wherein the at least one transmitting device comprises a plurality of transmitting devices and the at least one receiving device comprises a plurality of receiving devices, the pluralities of transmitting and receiving devices arranged with respect to one another such that the main extension directions of the transmitting devices are perpendicular to the main extension directions of the receiving devices.

11. The apparatus as claimed in claim 9, further comprising a control device configured to sequentially drive the transmitting devices for respectively providing the transmission signal.

12. The apparatus as claimed in claim 2, wherein the partial reception signals are canceled out in the second reception signal in such a way that a geometrical arrangement of the transmitting device, the geometrical arrangement of the receiving device, or the geometrical arrangements of the transmit and receiving devices are determined in a manner dependent on a symmetry property of the magnetic power field of the charging coils.

13. The apparatus as claimed in claim 12, wherein the charging coils are a double-D coil system, wherein primary coils of the double-D coil system are arranged in an x-y plane axially symmetrically with respect to a y-axis.

14. The apparatus as claimed in claim 12, wherein the charging coils are a circular coil system, wherein a primary coil of the circular coil system is located on a point of intersection of an x-axis and an y-axis of an x-y plane.

15. The apparatus as claimed in claim 12, wherein the receiving device comprises a predetermined number of receiving coils arranged with respect to the transmitting device in such a way that the transmission signal is induced into the respective receiving coils substantially in identical portions.

16. The apparatus as claimed in claim 15, wherein the receiving coils are arranged alongside one another in a main extension direction of the receiving device.

17. The apparatus as claimed in claim 16, wherein the at least one transmitting device comprises a plurality of transmitting devices and the at least one receiving device comprises a plurality of receiving devices, the pluralities of transmitting and receiving devices arranged with respect to one another such that the main extension directions of the transmitting devices are perpendicular to the main extension directions of the receiving devices.

18. A charging arrangement for inductively charging an electric vehicle, the charging arrangement comprising:

charging coils

a conductor presence detector comprising;

at least one transmitting device for providing a transmission signal in the form of a magnetic field, and

at least one receiving device for generating a first reception signal from the transmission signal provided by the transmitting device and induced into the receiving device,

wherein the transmitting device and the receiving device are formed in such a way that, when the electrically conductive body is present, a first reception signal forms and, when the electrically conductive body is absent, a second reception signal, different than the first reception signal, forms in the receiving device on account of the induced transmission signal, and

wherein the transmitting device and the receiving device are formed in a manner dependent on the magnetic power field of the charging coils in such a way that, when the electrically conductive body is absent, the second reception signal comprises partial reception signals formed in the receiving device on account of the induced transmission signal, the partial reception signals substantially cancelling one another out in the second reception signal.

19. The charging arrangement of claim 18, wherein the at least one transmit device comprises a plurality of transmit devices, further comprising a control device configured to sequentially drive the transmitting devices for respectively providing the transmission signal.

20. The charging arrangement of claim 18, wherein the transmitting device and the receiving device each have a form of a conductor loop twisted at least once.