Power transfer unit of a system for inductive power transfer, a method of manufacturing a primary power transfer unit and of operating a primary power transfer unit

• US 10,403,432 B2
• Filed: 02/15/2016
• Issued: 09/03/2019
• Est. Priority Date: 02/16/2015
• Status: Active Grant

• Current Assignee: IPT Group BV
• Original Assignee: Bombardier Primove Gmbh
• Inventors: Woronowicz, Konrad, Czainski, Robert
• Primary Examiner(s): Donovan, Lincoln D
• Assistant Examiner(s): Almo, Khareem E
• Application Number:
  US15/550,967
• Publication Number:
  US 20180025839A1
• Time in Patent Office: 1,296 Days
• Field of Search: None
• 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: H01F 27/363 made of electrically conductive material
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H01F 41/04 for manufacturing coils coils for transformer or inductances H01F27/28
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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 90/14 Plug-in electric vehicles

Abstract

A power transfer unit of a system for inductive power transfer, wherein the power transfer unit includes a winding structure, and at least one flux guiding means for guiding a magnetic flux of the electromagnetic field, wherein the at least one flux guiding means provides at least one low reluctance section with a first reluctance and at least one high reluctance section with a second reluctance, and the second reluctance is higher than the first reluctance. Also, a method of manufacturing a power transfer unit and a method of operating a power transfer unit.

Claims

1. A power transfer unit of a system for inductive power transfer, wherein the power transfer unit comprises:

a winding structure; and

at least one flux guiding means for guiding a magnetic flux of an electromagnetic field;

wherein the at least one flux guiding means comprises or provides at least one low reluctance section with a first reluctance and at least one high reluctance section with a second reluctance, wherein the second reluctance is higher than the first reluctance, wherein the at least one high reluctance section extends parallel to a lateral axis of the winding structure, wherein the lateral axis is an axis of a right-handed Cartesian coordinate system;

wherein a geometric centre or centreline of the at least one high reluctance section is arranged within a centre plane between two adjacent poles provided by the winding structure;

wherein the at least one high reluctance section is provided by a gap between two low reluctance sections, wherein the gap extends along a total width of the at least one flux guiding means;

wherein the winding structure comprises a first sub-winding and at least one second sub-winding, wherein a winding section of the first sub-winding and a winding section of the at least one second sub-winding extend parallel to each other and are arranged adjacent to each other within a common winding section, and the winding section of the first sub-winding and the winding section of the at least one second sub-winding extend along the lateral axis;

wherein the at least one high reluctance section is arranged under the common winding section; and

wherein the first sub-winding of the winding structure provides a pole if a current flows through the first sub-winding of the winding structure or the at least one second sub-winding of the winding structure provides a pole if a current flows through the at least one second sub-winding.

2. The power transfer unit according to claim 1, wherein the at least one flux guiding means is designed as a flux guiding layer.

3. The power transfer unit according to claim 1, wherein the flux guiding layer comprises one or more ferrite bars or ferrite plates, wherein the ferrite bars or ferrite plates extend parallel to a longitudinal axis of the winding structure, wherein the longitudinal axis is an axis of the right-handed Cartesian coordinate system.

4. The power transfer unit according to claim 1, wherein the at least one high reluctance section is provided at least partially by a diminution of a cross-sectional area of the at least one flux guiding means.

5. The power transfer unit according to claim 1, wherein the power transfer unit comprises at least one flux control means for controlling the flux in the flux guiding means.

6. The power transfer unit according to claim 1, wherein the at least one high reluctance section is arranged symmetrical with respect to the winding structure.

7. The power transfer unit according to claim 1, wherein a maximal length of the at least one high reluctance section along a longitudinal axis of the winding structure is higher than 0.0 mm and smaller than or equal to 30.0 mm.

10. A method of operating a power transfer unit according to claim 1, wherein the power transfer unit is energized.

11. The method of claim 10, wherein at least one flux control means of the power transfer unit is controlled such that a desired reluctance is provided in at least one section of the flux guiding means.

8. A method of manufacturing a power transfer unit comprising the steps of:

providing a winding structure; and

providing at least one flux guiding means for guiding a magnetic flux of an electromagnetic field such that the at least one flux guiding means comprises or provides at least one low reluctance section with a first reluctance and at least one high reluctance section with a second reluctance, wherein the second reluctance is higher than the first reluctance, wherein the at least one high reluctance section extends parallel to a lateral axis of the winding structure, wherein the lateral axis is an axis of a right-handed Cartesian coordinate system;

wherein a geometric centre or centreline of the at least one high reluctance section is arranged within a centre plane between two adjacent poles provided by the winding structure;

wherein the at least one high reluctance section is provided by a gap between two low reluctance sections, wherein the gap extends along a total width of the flux guiding means;

wherein the winding structure comprises a first sub-winding and at least one second sub-winding, wherein a winding section of the first sub-winding and a winding section of the at least one second sub-winding extend parallel to each other and are arranged adjacent to each other within a common winding section, and the winding section of the first sub-winding and the winding section of the at least one second sub-winding extend along the lateral axis;

wherein the at least one high reluctance section is arranged under the common winding section; and

wherein the first sub-winding of the winding structure provides a pole if a current flows through the first sub-winding or the at least one second sub-winding of the winding structure provides a pole if a current flows through the at least one second sub-winding.

9. The method according to claim 8, wherein the at least one high reluctance section is designed and or arranged such that a first predetermined field density at a predetermined reference point in a reference volume above or below the winding structure is provided, wherein the flux density at a predetermined reference point outside the reference volume is smaller than another predetermined flux density.