Primary unit comprising a plurality of coil sections for inductive charging

• US 10,576,831 B2
• Filed: 06/15/2017
• Issued: 03/03/2020
• Est. Priority Date: 12/18/2014
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Krammer, Josef
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): Piggush, Aaron
• Application Number:
  US15/624,155
• Publication Number:
  US 20170282724A1
• Time in Patent Office: 992 Days
• Field of Search: 320104, 320108, 320109
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/30 Constructional details of charging stations
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60L 53/38 specially adapted for charging by inductive energy transfer
• CPC Class Codes: H01F 27/2823 Wires H01F27/2866 takes precedence
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• 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: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• 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 primary unit is provided for producing an electromagnetic charging field for inductive coupling to a secondary coil. The primary unit has a multi-part primary coil, which includes N coil sections, with N>2, which are coupled to each other on a first end in the shape of a star. Moreover, the primary unit has N half-bridges, which are each coupled to a second end of the N coil sections. In addition, the primary unit has a control unit, which is configured to control the N half-bridges in relation to the secondary coil.

Claims

1. A primary unit for generating an electromagnetic charging field for inductive coupling to a secondary coil, the primary unit comprising:

a multipartite primary coil, which comprises N coil elements, where N>

2, which are coupled to one another in star at a respective first end;

N half-bridges, which in each case are coupled to a respective second end of the N coil elements; and

a control unit, which is configured to drive the N half-bridges depending on at least one of a position, a type and a shape of the secondary coil,

wherein current only flows through the N coil elements in the same phase.

2. The primary unit as claimed in claim 1, wherein the coil elements comprise circular coil elements, which are arranged laterally alongside one another.

3. The primary unit as claimed in claim 1, wherein

N=3;

the N coil elements comprise a first coil element, a second coil element and a third coil element;

the first coil element is arranged on a first side of the second coil element; and

the third coil element is arranged on a second side of the second coil element, said second side lying opposite the first side of the second coil element.

4. The primary unit as claimed in claim 2, wherein

N=3;

the N coil elements comprise a first coil element, a second coil element and a third coil element;

the first coil element is arranged on a first side of the second coil element; and

the third coil element is arranged on a second side of the second coil element, said second side lying opposite the first side of the second coil element.

5. The primary unit as claimed in claim 1, wherein

N=5;

and

the N coil elements comprise a central coil element, which is surrounded by four further coil elements.

6. The primary unit as claimed in claim 2, wherein

N=5;

and

the N coil elements comprise a central coil element, which is surrounded by four further coil elements.

7. The primary unit as claimed in claim 1, wherein the control unit is configured to:

operate at least two of the N half-bridges mutually in differential mode;

operate at least two of the N half-bridges mutually in common mode; and

/or

operate at least one of the N half-bridges in such a way that no current flows through the corresponding coil element.

8. The primary unit as claimed in claim 3, wherein the control unit is configured to:

operate at least two of the N half-bridges mutually in differential mode;

operate at least two of the N half-bridges mutually in common mode; and

/or

operate at least one of the N half-bridges in such a way that no current flows through the corresponding coil element.

9. The primary unit as claimed in claim 5, wherein the control unit is configured to:

operate at least two of the N half-bridges mutually in differential mode;

operate at least two of the N half-bridges mutually in common mode; and

/or

operate at least one of the N half-bridges in such a way that no current flows through the corresponding coil element.

10. The primary unit as claimed in claim 1, wherein the control unit is configured to operate at least two of the N half-bridges with a charging frequency;

wherein the charging frequency corresponds to a frequency of the electromagnetic charging field.

11. The primary unit as claimed in claim 1, wherein the control unit is configured to drive the N half-bridges depending on a type of the secondary coil and/or depending on a position of the secondary coil relative to the multipartite primary coil.

12. The primary unit as claimed in claim 11, wherein the secondary coil is of solenoid type, double-D type and/or circular type.

13. The primary unit as claimed in claim 12, wherein the control unit is configured to:

determine a type of the secondary coil;

determine predefined operating data for the N half-bridges depending on the determined type; and

drive the N half-bridges in accordance with the predefined operating data.

14. The primary unit as claimed in claim 11, wherein the control unit is configured to:

determine a type of the secondary coil;

determine predefined operating data for the N half-bridges depending on the determined type; and

drive the N half-bridges in accordance with the predefined operating data.

15. The primary unit as claimed in claim 13, wherein the control unit is configured to:

determine the position of the secondary coil relative to the multipartite primary coil;

wherein the position comprises a lateral offset between the secondary coil and the multipartite primary coil; and

determine the predefined operating data depending on the determined position as well.

16. The primary unit as claimed in claim 14, wherein the control unit is configured to:

determine the position of the secondary coil relative to the multipartite primary coil;

wherein the position comprises a lateral offset between the secondary coil and the multipartite primary coil; and

determine the predefined operating data depending on the determined position as well.

17. The primary unit as claimed in claim 1, wherein the primary unit is configured to inductively charge an electrical storage unit of a vehicle.