Main coil assembly, and module comprising a main coil assembly

Abstract

The invention relates to a main coil assembly (1) for a ground module (GPM) or a vehicle module (CPM) of an inductive charging system for a vehicle, the main coil assembly (1) having a main coil (2) and magnetic flux guiding elements (4). According to the invention: • the magnetic flux guiding elements (4) are arranged in a first cooling region (51); • the main coil (2) is arranged in a second cooling region (52); and • coolant distribution elements (53) are provided which distribute a coolant flow, wherein a first portion of the coolant flow passes through the first cooling region (51), and a second portion of the coolant flow passes through the second cooling region (52).

Description

[0001] MAIN COIL ASSEMBLY AND MODULE WITH ONE

[0002] MAIN COIL ASSEMBLY

[0003] The present invention relates to a main coil assembly for a power conversion arrangement, in particular for supplying energy to an electric vehicle. A power conversion arrangement can be provided for converting the electrical power of an electrical supply current into electromagnetic power of an oscillating electromagnetic field, or vice versa. A power conversion arrangement comprises a magnetic assembly for receiving a current and for radiating an oscillating electromagnetic field, or vice versa, and an electronic assembly for receiving the electrical supply current and converting it into an alternating electrical current for supplying the magnetic assembly, or vice versa.

[0004] The power conversion assembly further comprises heat dissipation means for dissipating heat generated by the electronic assembly and / or the magnetic assembly during their respective power conversion operation.

[0005] Electric vehicle batteries can be charged with alternating current (AC) or direct current (DC). Typical AC chargers can provide a charging power of up to 22 kW. AC charging systems can be divided into wired charging systems and wireless charging systems, with wireless charging systems primarily implemented as inductive charging systems (ICS). An ICS typically consists of two separate modules, often referred to as a ground pad module (GPM) and a car pad module (CPM). The GPM is installed outside the electric vehicle, while the CPM is mounted inside the electric vehicle, usually on the underside of the vehicle. The CPM can receive the oscillating electromagnetic, predominantly magnetic, field from the GPM, convert it into an alternating current, further convert it (typically rectify it), and then generate a charging current (typically DC) used to charge a vehicle's traction battery.Wireless charging systems are often more convenient for the user, as no manual intervention is usually required to start charging the battery other than parking the vehicle over the GPM.

[0006] A power conversion assembly can be part of a GPM, for receiving an electric current and emitting an oscillating electromagnetic field. Similarly, a power conversion assembly can be part of a CPM, which receives the oscillating electromagnetic field from the GPM and converts it into a current. In principle, in both cases, the GPM or CPM can be capable of regenerative energy flow, i.e., also for energy flow in the opposite direction, i.e., from the vehicle to the charging device.

[0007] A GPM typically comprises a magnetic assembly and an electronic assembly. The magnetic assembly, also referred to below as the main coil assembly, comprises a coil and ferrite elements that heat up during operation of the GPM and must be cooled. The electronic assembly must also be cooled. The magnetic and electrical assemblies can be arranged in a common housing or in separate, functionally coupled modules. Air cooling can be provided to cool the electronic assembly and / or the magnetic assembly. The object of the invention is to provide a main coil assembly with improved cooling properties, as well as a module with such a main coil assembly.

[0008] This object is achieved by a main coil assembly having the features of patent claim 1 and a module according to patent claim 10.

[0009] The main coil assembly is intended for a ground module (GPM) or a vehicle module (CPM) of an inductive charging system for a vehicle, wherein the main coil assembly comprises a main coil and magnetic flux guiding elements.

[0010] • the magnetic flux guide elements are arranged in a first cooling area;

[0011] • the main coil is arranged in a second cooling area;

[0012] • Cooling medium dividing elements are present which divide a cooling medium flow, wherein a first portion of the cooling medium flow flows through the first cooling area and a second portion of the cooling medium flow flows through the second cooling area.

[0013] This makes it possible to dissipate heat loss that occurs in the main coil and the magnetic flux guide elements separately, without the waste heat from one cooling area affecting the components in the other cooling area.

[0014] In embodiments, the magnetic flux guiding elements and the main coil are arranged in mutually parallel planes.

[0015] This makes it possible to realize a flat design of the main coil assembly. The main coil assembly of the GPM and the main coil assembly of the CPM are magnetically coupled during operation to transfer energy from the GPM to the CPM or vice versa.

[0016] In embodiments, the main coil is arranged above the magnetic flux guide elements in the GPM in an operating state or when the main coil assembly is installed. As a result, an effective area of ​​the main coil of the GPM, in which a CPM can be arranged, is located above the GPM.

[0017] By locating the main coil above the GPM, its heat loss, which is higher than that of the magnetic flux guide elements, has less influence on the magnetic flux guide elements than if it were located below.

[0018] In embodiments, the main coil is arranged below the magnetic flux guide elements in the CPM in an operating state or when the main coil assembly is installed. As a result, an effective area of ​​the main coil of the CPM, in which a GPM can be arranged, is located below the CPM.

[0019] In embodiments, the magnetic flux guide elements and the main coil are held by a support element, wherein the support element forms a separation between the first cooling region and the second cooling region.

[0020] This makes it possible to separate heat loss from the main coil from the magnetic flux guide elements. To this end, the separation is essentially free of openings or holes that would allow the cooling medium to flow between the first and second cooling areas.

[0021] In embodiments, the magnetic flux guide elements are mounted on the support element at a distance from the support element. The cooling medium can therefore flow between the magnetic flux guide elements and the support element. In particular, it can also flow along the magnetic flux guide elements on one side of the magnetic flux guide elements that is spaced from the support element. This allows cooling of the magnetic flux guide elements on their two main surfaces.

[0022] In embodiments, it is the case that the cooling medium distribution elements are arranged on an edge of the carrier element, in particular wherein the cooling medium distribution elements are formed integrally as part of the carrier element.

[0023] This allows for a simple design of the cooling medium distribution elements. For example, an edge region of the support element can be extended in the direction opposite the cooling medium flow. In particular, the edge region can be bent, with the cooling medium flow being distributed between the two cooling areas depending on the angle at which it is bent.

[0024] In embodiments, it is the case that the cooling medium distribution elements extend along one side of the carrier element, hereinafter referred to as the inflow side, in particular along at least 50% or at least 60% or at least 70% or at least 80% or at least 90% of a length of the inflow side.

[0025] This allows for uniform airflow over a large area of ​​the two cooling zones. The main coil assembly can have a substantially rectangular basic shape, with the upstream side forming one of the sides of the rectangle.

[0026] In embodiments, it is the case that the cooling medium distribution elements are arranged and designed such that the second portion of the cooling medium flow is higher than the first portion of the cooling medium flow, in particular wherein the second portion is at least 1.2 times, or at least 1.5 times, or at least 1.8 times, or at least 2 times the first portion.

[0027] This makes it possible to adapt the proportions of the cooling medium flow to the heat loss, which occurs to varying degrees in the main coil and the magnetic flux guide elements.

[0028] In embodiments, the main coil assembly has an inlet opening which supplies the cooling medium flow as ambient air from an external environment of the floor module (GPM) or vehicle module (CPM) to the cooling medium distribution element, in particular wherein the inlet opening is designed in a slot-like manner as a slot with a longitudinal direction, and in particular wherein the inlet opening extends in this longitudinal direction along at least 50% or at least 60% or at least 70% or at least 80% or at least 90% of an extension of the floor module (GPM) or vehicle module (CPM) in this longitudinal direction.

[0029] In embodiments, the inlet opening extends in this longitudinal direction along between 5% and 90% of the said extension of the floor module (GPM) or vehicle module (CPM) in this longitudinal direction,

[0030] Cooling the main coil and the magnetic flux guide elements directly by the ambient air allows for efficient cooling, in contrast to systems where the cooling system uses an intermediate circuit for heat exchange between these elements and the ambient air. The magnetic flux guide elements, for example, tiles made of a ferrite material, can be cooled directly by the ambient air. For this purpose, the tiles can be exposed to ambient air on one or both sides. The main coil, for example, an insulated stranded cable, can be cooled directly by the ambient air.

[0031] Although ambient air cooling can potentially introduce moisture into the device, the airflow can also dry the device. The advantages of direct cooling of the magnetic flux guide elements and current conductors outweigh the disadvantages.

[0032] The slot-shaped inlet opening supports the even flow over a large area of ​​the two cooling zones.

[0033] In embodiments, it is the case that the first cooling area and / or the second cooling area are located in the intake area of ​​a cooling medium conveying device, in particular a fan.

[0034] In embodiments, it is the case that the first cooling area and / or the second cooling area are located in the outflow area of ​​a cooling medium conveying device, in particular a fan.

[0035] The cooling medium conveying device, especially the fan, can thus also operate in the opposite direction. This reverses the intake and exhaust airflow. Air is drawn in from the power electronics side and expelled from the coil side. This is because the power electronics can be warmer than the coil side, and it can therefore be more effective to cool the power electronics first with cool ambient air.

[0036] In this case, the upstream side with the cooling medium distribution element is located in the area of ​​the main coil assembly, which is first flowed through by a cooling medium flowing out of another device area and / or a cooling medium conveying device. The module is designed as a ground module (GPM) or vehicle module (CPM) of an inductive charging system for a vehicle, with a main coil assembly as described herein. The module has a first device area in which the main coil assembly is arranged, and a second device area in which a power electronics unit is arranged.In this case, a cooling medium conveying device, in particular a fan, is arranged to suck in cooling medium through the first device area and to convey it further through the second device area or to suck in cooling medium through the second device area and to convey it further through the first device area, in particular wherein the first device area and the second device area each have a substantially rectangular basic shape and extend in a common plane, and in particular are separated from one another along a flat separating surface.

[0037] This makes it possible to easily structure the module into interchangeable sub-modules corresponding to the first device area and the second device area.

[0038] In embodiments, the power electronics unit is arranged in a fluid-tight power electronics housing, with a pressure equalization membrane between the interior of the power electronics housing and an ambient air and / or a cooling medium flow through the second device area,

[0039] Further preferred embodiments emerge from the dependent patent claims. The subject matter of the invention is explained in more detail below with reference to preferred embodiments, which are illustrated in the accompanying drawings. They show schematically:

[0040] Figure 1 shows a main coil assembly seen from a first side with a main coil;

[0041] Figure 2 shows the main coil assembly seen from a second side with magnetic flux guide elements;

[0042] Figure 3 shows a module with the main coil assembly arranged therein in a cut-away view;

[0043] Figure 4 shows an overall view of the module in a cut-away view.

[0044] The reference symbols used in the drawings and their meanings are summarized in the list of reference symbols. In general, identical or equivalent parts are provided with the same reference symbols in the figures.

[0045] Figures 1 and 2 show a main coil assembly 1 viewed from a first and a second side. The main coil assembly 1 is flat, with dimensions ven between 40 cm by 40 cm and 100 cm by 100 cm. The main coil assembly 1 forms an independent structural unit with a carrier element 5 and a main coil 2 arranged thereon on the first side, and ferrite tiles arranged on the second side, hereinafter referred to as magnetic flux guide elements 4 or ferrites 4. The main coil 2 has one or more current conductors 3, which are guided and / or held in guide and / or holding elements 31. The guide and / or holding elements 31 can be formed integrally on the carrier element 5. The magnetic flux guide elements 4 are tile-shaped and are arranged in at least one plane. They can be arranged in several planes that lie parallel to one another.Figure 2 shows the majority of ferrites 4 in a first plane, directly adjacent to the carrier element 5, with one of the ferrites 4 omitted for clarity. A single ferrite 4 lies in a second plane and covers a gap between ferrites 4 in the first plane. In embodiments not shown, further layers of ferrites 4 may be present, each in its own plane that is parallel to the other planes. For example, the ferrites 4 all have the same shape. Two opposite corners are chamfered, which, with respect to a rectangular shape of the elements, can be referred to as recesses 41. The ferrites 4 are arranged such that recesses 41 of adjacent ferrites 4 lie opposite one another, leaving a larger area free between them. Support elements 55 of the carrier element 5 extend through such areas in a direction normal to the plane of the carrier element 5.If the main coil assembly 1 is arranged in a module with a housing, forces acting on the housing can be diverted through the plane of the support element 5 to opposing housing parts. This reduces or eliminates mechanical stress and deformation in the plane of the support element 5.

[0046] The two figures also show a cooling medium dividing element 53 which is formed or attached to the carrier element 5 and divides a flow of a cooling medium so that a part flows over the main coil 2 and another part over the ferrites 4.

[0047] Figure 3 shows a sectioned view of part of a module 10 with a main coil assembly 1 arranged therein. The module 10 shown is, by way of example, part of a GPM. As already described above, the main coil assembly 1 has a support element 5, which has a main coil 2 – here on the top side – and magnetic flux guide elements 4 – here on the bottom side. The main coil assembly 1 is arranged in a housing 13. The housing 13 has an elongated slot along one side. For example, the slot acts as an inlet opening 54, i.e., ambient air flows into the housing 13 as a cooling medium through the inlet opening 54. The air flow is represented by block arrows. The incoming air is divided into a first and a second portion at the cooling medium distribution element 53. The first portion flows through a first cooling region 51, where it cools the magnetic flux guide elements 4.The second portion flows through a second cooling region 52 and cools the main coil 2, in particular the current conductor 3 of the main coil 2.

[0048] Since the power loss in the area of ​​the main coil 2 is generally greater than in the area of ​​the magnetic flux guide elements 4, the cooling medium distribution element 53 is shaped such that the second portion is higher than the first. The cooling medium distribution element 53 extends—as can be seen more clearly in Figures 1 and 2—along one side of the support element 5. It extends along as large an area of ​​this side as possible. Likewise, the inlet opening 54 extends along as large an area as possible. Similarly, a supply opening, which supplies the cooling medium from another device area and / or a cooling medium conveying device, extends over as large an area as possible along one side of the main coil assembly 1.

[0049] Figure 4 shows an overall view of the module 10 in a cutaway view. The main coil 2 with the housing 13 forms a first device area 11. A second device area 12 has a power electronics unit 14. This powers the main coil 2 or is powered by it, depending on the direction of the energy flow. The second device area 12 has a fan 15, which draws in the ambient air as a cooling medium through the first device area 11 with the main coil assembly 1 and thus subsequently also cools the power electronics unit 14. In embodiments, the fan 15 acts in the opposite direction and conveys the cooling medium in the opposite direction, first through the second device area 12, in particular the power electronics unit 14, and then through the main coil assembly 1.The support elements 55 transmit loading forces, for example from a car driving over the module 10, from an upper section of the housing 13 through the main coil assembly 1 to a lower section without the magnetic flux guide elements 4 being loaded as a result.

[0050] LIST OF REFERENCE SYMBOLS

[0051] 1 main coil assembly

[0052] 2 main coil

[0053] 3 conductors

[0054] 10 Module

[0055] 11 first device area

[0056] 12 second device area

[0057] 13 module housings

[0058] 14 Power electronics unit

[0059] 15 fans

[0060] 16 power electronics housings

[0061] 31 Guide and / or support element

[0062] 4 Magnetic flux guide element

[0063] 41 Recess

[0064] 5 support element

[0065] 51 first cooling area

[0066] 52 second cooling area

[0067] 53 Cooling medium distribution element

[0068] 54 Inlet opening (for cooling medium)

[0069] 55 Support element

Claims

PATENT CLAIMS 1. Main coil assembly (1) for a ground module (GPM) or a vehicle module (CPM) of an inductive charging system for a vehicle, wherein the main coil assembly (1) comprises a main coil (2) and magnetic flux guide elements (4), characterized in that • the magnetic flux guide elements (4) are arranged in a first cooling area (51); • the main coil (2) is arranged in a second cooling area (52); • cooling medium dividing elements (53) are present which divide a cooling medium flow, wherein a first portion of the cooling medium flow flows through the first cooling region (51), and / or a second portion of the cooling medium flow flows through the second cooling region (52), 2. Main coil assembly (1) according to claim 1, wherein the magnetic flux guide elements (4) and the main coil (2) are arranged in mutually parallel planes, in particular wherein in an operating state of the main coil assembly (1) the main coil (2) is arranged above the magnetic flux guide elements (4).

3. Main coil assembly (1) according to one of the preceding claims, wherein the magnetic flux guiding elements (4) and the main coil (2) are held by a support element (5), the support element (5) forming a separation between the first cooling region (51) and the second cooling region (52).

4. Main coil assembly (1) according to claim 3, wherein the cooling medium distribution elements (53) are arranged on an edge of the carrier element (5), in particular wherein the cooling medium distribution elements (53) are formed integrally as part of the carrier element (5).

5. Main coil assembly (1) according to claim 4, wherein the cooling medium distribution elements (53) extend along one side of the carrier element (5), hereinafter referred to as the upstream side, in particular along at least 50% or at least 60% or at least 70% or at least 80% or at least 90% of a length of the upstream side, 6. Main coil assembly (1) according to one of the preceding claims, wherein the cooling medium distribution elements (53) are arranged and configured such that the second portion of the cooling medium flow is higher than the first portion of the cooling medium flow, in particular wherein the second portion is at least 1.2 times, or at least 1.5 times, or at least 1.8 times, or at least 2 times the first portion.

7. Main coil assembly (1) according to one of the preceding claims, comprising an inlet opening (54) which supplies the cooling medium flow as ambient air from an external environment of the floor module (GPM) or vehicle module (CPM) to the cooling medium distribution element (53), in particular wherein the inlet opening (54) is designed in the shape of a slot with a longitudinal direction, and in particular wherein the inlet opening (54) extends in this longitudinal direction along at least 50% or at least 60% or at least 70% or at least 80% or at least 90% of an extension of the floor module (GPM) or vehicle module (CPM) in this longitudinal direction.

8. Main coil assembly (1) according to one of the preceding claims, wherein the first cooling region (51) and / or the second cooling region (52) are located in the intake region of a cooling medium conveying device (15), in particular a fan (15). , Main coil assembly (1) according to one of claims 1 to 6, wherein the first cooling region (51) and / or the second cooling region (52) are located in the outflow region of a cooling medium conveying device (15), in particular a fan (15).

10. A module (10), as a floor module (GPM) or vehicle module (CPM) of an inductive charging system for a vehicle, with a main coil assembly (1) according to one of the preceding claims, comprising a first device region (11) in which the main coil assembly (1) is arranged, and a second device region (12) in which a power electronics unit (14) is arranged, wherein a cooling medium conveying device (15), in particular a fan (15), is arranged to suck in cooling medium through the first device region (11) and to convey it further through the second device region (12) or to suck in cooling medium through the second device region (12) and to convey it further through the first device region (11), in particular wherein the first device region (11) and the second device region (12) each have a substantially rectangular basic shape and extend in a common plane, and in particular are separated from one another along a flat separating surface.

11. Module (10) according to claim 10, wherein the power electronics unit (14) is arranged in a fluid-tight power electronics housing (16), with a pressure equalization membrane between the interior of the power electronics housing (16) and an ambient air and / or a cooling medium flow through the second device area (12),

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