Wireless charging module with cooling channel
The wireless charging module addresses heat dissipation challenges by employing a coolant channel structure with flow guiding elements to enhance heat transfer, ensuring efficient cooling of both electronic and magnetic subassemblies, thus improving performance.
Patent Information
- Application Number
- JP2025574988
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-07-07
- Filing Date
- 2024-07-01
- Publication Date
- 2026-07-09
AI Technical Summary
Existing wireless charging modules for electric vehicles face challenges in effectively dissipating heat generated by the electronic and magnetic subassemblies, which are concentrated and dispersed, respectively, leading to inefficient heat transfer and cooling.
A wireless charging module with a cooling system featuring a coolant channel structure and flow guiding elements with specific dimensions and cross-sections to enhance heat transfer through turbulence and vortices, optimizing heat dissipation from both subassemblies.
The design significantly improves heat transfer efficiency by accelerating coolant flow and inducing turbulence, effectively cooling the electronic and magnetic subassemblies, thereby enhancing the performance and reliability of the charging module.
Smart Images
Figure 2026522892000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a wireless charging module for charging a battery or supplying power to an electrical load of a vehicle.
Background Art
[0002] The battery of an electric vehicle can be charged with alternating current (AC) or direct current (DC). A typical AC charging device can provide a charging power of up to 22 kW. The AC charging system can be subdivided into a cable-connected charging system and a cableless charging system, and the cableless charging system is mainly designed as an inductive charging system (ICS). Generally, a cable-connected AC charging device is incorporated into an electric vehicle and is also called an in-vehicle charging device. Generally, an ICS often consists of two separate modules, often called a ground pad module (GPM) and a car pad module (CPM). The GPM is installed outside the electric vehicle, while the CPM is installed inside the electric vehicle, generally under the vehicle. The electromagnetic interaction between the GPM and the CPM enables energy transmission from the GPM to the CPM and vice versa, and then the CPM is used to charge the battery of the electric vehicle. The cableless charging system is generally more comfortable for the user because it generally does not require manual intervention to start the battery charging procedure, except for placing the vehicle on the GPM.
Summary of the Invention
[0003] The wireless charging module according to the present invention can be used particularly for charging a high-voltage battery or supplying power to an electrical load of a vehicle. In this case, it can be called a car pad module (CPM). This can receive an oscillating magnetic field from an external emitter, which can be called a ground pad module (GPM). The CPM converts the oscillating electromagnetic field, mainly the magnetic field, into alternating current, and the alternating current is converted (typically rectified), thereby becoming a charging current (typically direct current) used for charging the battery or supplying power to the electrical load.
[0004] A wireless charging module can also be called a power converter. It helps convert the electromagnetic energy of an oscillating electromagnetic field into electric power, or electric power that can be used to charge a power storage device or to power an electrical load.
[0005] Regarding cooling, it is important to understand that a CPM can include two heat-generating regions: an electronic subassembly (power electronics) that generates a lot of heat but is concentrated in a specific location within the device and has relatively high-density heat-generating elements, and a magnetic subassembly (coils and ferrite) that generates less heat but is spatially dispersed to a relatively high degree and therefore has low-density heat-generating elements.
[0006] The objective of the present invention is to create a wireless charging module of the type described above, in which heat transfer from the heat-generating element to the coolant for cooling the charging module is improved.
[0007] This objective is achieved by a wireless charging module having the features of patent claim 1.
[0008] The wireless charging module is useful for charging the vehicle's battery and / or supplying power to the vehicle's electrical load and / or supplying energy from the vehicle's battery and / or supplying energy from the vehicle's energy source. It includes the following: • A first, in particular, magnetic subassembly for receiving an oscillating electromagnetic field and converting it to an alternating current, • A second, particularly an electronic subassembly, for receiving alternating current and converting it to current for charging the traction battery. A cooling system that uses the flow of coolant to dissipate the heat generated by the two subassemblies during their operation. The cooling system comprises a cooling channel structure having at least one coolant channel and at least two flow guiding elements extending laterally with respect to the flow direction. • The width of the flow induction element is greater than the distance between flow induction elements.
[0009] This ratio between the width of the flow guide elements and the distance between them results in an acceleration of the coolant flow into the intermediate space between the flow guide elements, which in turn leads to turbulence. This turbulence occurs in the region between the flow guide elements, increasing heat transfer between the coolant flow and the flow guide elements.
[0010] The statement that the width of a flow guide element is greater than the distance between flow guide elements can also be stated more clearly as follows: Considering the flow in a plane perpendicular (upright) to the flow direction, each flow guide element extends along a first direction, and in a second direction perpendicular to the first direction, the width of the flow guide element is greater than the distance between flow guide elements. This distance is equal to the width of the passage between the flow guide elements.
[0011] In the embodiment, considering the flow in a plane perpendicular to the flow direction, the width of the flow guide element in the second direction is in all cases greater than the distance between the outer flow guide element and the adjacent channel wall. As a result, the improved heat transfer turbulence described above is realized even in the edge regions of the row of flow guide elements.
[0012] In the embodiment, the width of the flow guide element is at least 1.5 times, in particular at least 2 times, and in particular at least 3 times, the distance between the flow guide elements.
[0013] Therefore, heat transfer to vortices and flow-inducting elements is further increased. The pressure drop between flow-inducting elements is higher as the distance decreases, but the pressure drop can be the same or smaller for the same heat transfer due to the fact that fewer flow-inducting elements are needed overall for greater heat transfer.
[0014] In the embodiment, when considered within a plane parallel to the flow direction and parallel to a second direction (hereinafter referred to as the flow plane), the flow guiding elements have at least a substantially semicircular cross-section on their sides that receive and face the flow. In particular, on the sides away from the flow, they similarly have at least a substantially semicircular cross-section.
[0015] More precisely, considering the flow within a plane parallel to both the flow direction and the second direction (hereinafter referred to as the flow plane), the flow guiding element may have at least a nearly semicircular cross-section on its side that receives and faces the flow. Since the flow plane is parallel to the second direction, it extends perpendicular (upright) to the first direction.
[0016] In this embodiment, the flow guide element has a circular cross-section.
[0017] This allows for a particularly simple design of flow induction elements.
[0018] In the embodiment, the flow guide element has an elliptical or oval cross-section.
[0019] This allows the turbulent flow region and the improved heat transfer region to extend along the flow induction element, similar to the geometry described later.
[0020] In the embodiment, flow guide elements are positioned in a section of the curved coolant channel, the length of the flow guide elements in the flow direction is greater than the width of the flow guide elements perpendicular (orthogonal) to the flow direction, and in intermediate regions or passages between flow guide elements extending in the flow direction, the distance between flow guide elements at different positions within the intermediate region is essentially the same.
[0021] This allows the concept of the present invention to be realized even in regions that curve and extend.
[0022] In the embodiment, the length of the flow guide element in the flow direction is less than 2.5 times the width of the flow guide element perpendicular to the flow direction, and in particular is at least approximately 2 times.
[0023] This makes it possible to achieve, at least nearly, optimal heat transfer conditions. In the embodiment, the length of the flow guide element in the flow direction is greater than 1.5 times the width of the flow guide element.
[0024] In an embodiment, the flow guiding element extends from a first inner wall of the coolant channel to an opposite second inner wall or at least substantially to the second inner wall.
[0025] Thereby, the flow guiding element can be fastened or arranged on the first inner wall, and the design and manufacture of the second inner wall are simplified.
[0026] In an embodiment, the flow guiding element is made of metal.
[0027] Thereby, good thermal conductivity of the flow guiding element can be realized.
[0028] In an embodiment, the flow guiding element can be formed as an integral part on an inner wall of a coolant channel formed from metal.
[0029] Thereby, good heat transfer from the inner wall to the flow guiding element can be realized. Typically, the portion where the inner wall is formed is arranged to receive heat from the subassembly to be cooled.
[0030] In an embodiment, the flow guiding element is inserted into an inner wall of a coolant channel formed from a non-metallic material and is guided to a heat transfer body arranged to receive heat from a subassembly that generates and is cooled by heat during operation.
[0031] Thereby, good heat transfer from the inner wall to a subassembly that generates and is cooled by heat during operation can be realized even if the channel wall is formed of a body with poor thermal conductivity.
[0032] In an embodiment, the coolant channel includes at least one cooling section, and the flow guiding element is arranged in this cooling section to dissipate heat from at least one of a subassembly that generates and is cooled by heat during operation, particularly a magnetic subassembly and an electronic subassembly.
[0033] In the embodiment, the coolant channel has an essentially rectangular cross-section, its extension along a first direction is hereafter referred to as height, and its extension along a second direction is hereafter referred to as width, the width being at least three times the height.
[0034] In the embodiment, the cooling channel structure is positioned between at least one first portion and a second portion, and one or more channels of the cooling channel structure are formed by recesses in the first portion and / or the second portion. In particular, the first portion and / or the second portion are plate-like or broadly extending.
[0035] Therefore, the first and second parts are applied to each other to form a semishell that forms a cooling channel structure having one or more coolant channels.
[0036] In the embodiment, the first and second cooling sections are arranged on coolant channels that extend parallel to each other.
[0037] In this embodiment, the first and second cooling sections are positioned along the same coolant channel, and the positions are continuous in the flow direction.
[0038] Therefore, two or more cooling sections can exist. If there is only one coolant channel, the cooling sections are positioned along this coolant channel. If there are two or more coolant channels, the cooling sections can be positioned on different coolant channels.
[0039] In the embodiment, at least one of the first and second parts forms a support structure that supports at least one of the magnetic subassembly and the electronic subassembly.
[0040] In the embodiment, there is at least one of the following states:
[0041] The magnetic subassembly is assembled on the first or second part adjacent to the first cooling section and optionally adjacent to the second cooling section.
[0042] The electronic subassembly is assembled on the first or second part, adjacent to the second cooling section.
[0043] Further preferred embodiments can be derived from the dependent claims.
[0044] The subject matter of the present invention will be described in more detail through examples of preferred embodiments shown in the accompanying drawings. In each case, the following is schematically shown: [Brief explanation of the drawing]
[0045] [Figure 1] A garage with a vehicle mounted on a cableless charging station. [Figure 2] Cableless charging station and cableless charging device. [Figure 3] Cableless charging device. [Figure 4] Cross-sectional view of a cableless charging device. [Figure 5] Detailed view of a similar cross-section with flow-guiding elements. [Figure 6] Cooling section with flow guide elements. [Figure 7] Flow around a flow-inducing element. [Modes for carrying out the invention]
[0046] The reference numbers used in the drawings and their meanings are listed in the reference number list. Generally, identical or functionally equivalent parts in a drawing are assigned the same reference number.
[0047] The plan view in Figure 1 shows a garage 1 in which vehicle 2 is parked, with a cableless charging station 3 located outside the vehicle 2 and equipped with an emitter for transmitting vibrational magnetic fields, above it. The charging station 3 is visible because vehicle 2 is represented transparently. Such a charging solution is very convenient, and the driver is freed from connecting and disconnecting charging cables.
[0048] Figure 2 is an enlarged view of Figure 1, showing a cableless charging station 3 and a cableless charging device 4 "floating" above the charging station 3 for charging the vehicle's high-voltage battery 5. The aforementioned charging device 4 is installed on the vehicle, which means that the rest of the vehicle is not visible in this figure.
[0049] Figure 3 shows a perspective view of the charging device 4.
[0050] Figure 4 shows a schematic cross-sectional view of a cableless charging device 4, which may also be called a wireless charging module. The first part 41 and the second part 42 form a support structure for components to be further described. The first part 41 and / or the second part 42 may each consist of several separate parts. Furthermore, a housing, which is not shown, may also exist. The electronic subassembly 7 is located on the first part 41. This results in a relatively large amount of waste heat in a relatively small space. The magnetic subassembly 6 is located on or within the second part 42. This comprises coil leads 62 and ferrite elements 61. These result in a relatively small amount of waste heat that is distributed over a larger space.
[0051] The coolant channel 90 of the cooling channel structure 9 is formed between a first portion 41 and a second portion 42 by recesses in one or both of these portions. The coolant channel 90 can be sealed by a sealing element 49. The coolant channel 90 comprises a first cooling section 91 that primarily cools a portion of the magnetic subassembly 6, and a second cooling section 92 that cools the electronic subassembly 7 and, in this embodiment, also cools a portion of the magnetic subassembly 6. Thus, the second cooling section 92 is designed to dissipate a larger amount of heat per unit time than the first cooling section 91.
[0052] The first cooling section 91 comprises a smooth wall structure 43. The second cooling section 92 comprises a structured wall structure 44. A greater amount of heat is dissipated due to the fact that the structured wall structure 44 provides higher heat transfer than the smooth wall structure 43, and / or the fact that there is more coolant flow in the second cooling section 92 than in the first cooling section 91. The structured wall structure 44 is designed in the form of vortex structures or flow-guiding elements 45 that protrude into the coolant channel 90.
[0053] Figures 5, 6, and 7 show the arrangement of flow guide elements 45 in the coolant flow 80 of the coolant channel 90. In Figure 5, not all parts of the cross section are shown as in Figure 4. Figure 6 is a wireframe representation of different types of flow guide elements 45 in a cross section of the coolant channel 90. The flow guide elements 45 are formed in or inserted into a second section 42. They extend from the first inner wall 94 of the coolant channel 90 to the opposite second inner wall 95, or at least to approximately the second inner wall. In other embodiments, the flow guide elements 45 extend from the first section 41 to the second section 42.
[0054] Viewed from the direction of the coolant flow 80, the width of the flow guide elements 45 is greater than the distance between the flow guide elements 45. Alternatively or additionally, the width of the outer flow guide element 45 is greater than the distance between the outer flow guide element 45 and each adjacent lateral inner wall 96 of the coolant channel 90. The aforementioned distances are equal to the width of the passage between the two flow guide elements 45, or between the outer flow guide element 45 and the adjacent lateral inner wall 96. The described ratio of width to distance results in greater acceleration and turbulence, i.e., larger vortices between the flow guide elements 45 or between the outer flow guide element 45 and the adjacent lateral inner wall 96. This, in turn, results in a significant improvement in heat transfer from the coolant flow 80 to the flow guide elements 45 or the respective lateral inner walls 96.
[0055] In Figure 6, the flow guide elements 45 in the right-hand column are cylindrical and therefore have a circular cross-section. The flow guide elements 45 in the left-hand column have an elliptical cross-section. This makes the length of the flow guide elements 45 greater than the width, expanding the area in which turbulence contacts the flow guide elements 45. As the length increases, the vortices between the flow guide elements 45 decrease, and consequently, heat transfer also decreases. Therefore, the preferred ratio of width to length is at least about 1:2.
[0056] The different cross-sectional combinations shown in Figure 6 are for illustrative purposes only. In the embodiment, there are one or more rows of flow guide elements, each having the same cross-section. In the embodiment, the coolant channel extends along a curve, and the flow guide elements 45 have a bow-elliptical cross-section so that the passage or intermediate region between the flow guide elements 45 has essentially a constant cross-section.
[0057] Figure 7 visualizes the vortices in the coolant flow 80 induced by the flow guide elements 45. Bright areas of the flow correspond to weak vortices with laminar or stagnant flow. Dark areas correspond to strong vortices. Therefore, these areas are located in the passages between the flow guide elements 45, resulting in good heat transfer. [Explanation of Symbols]
[0058] 1...Garage, 2...Vehicle, 3...Charging station, 4...Cableless charging device, 41...First part, 42...Second part, 43...Smooth wall structure, 44...Structured wall structure, 45...Flow guide element, 46...Side receiving flow, 47...Side away from flow, 49...Seal element, 5...Battery, 6...Magnetic subassembly, 61...Ferrite element, 62...Coil lead, 7...Electronic subassembly, 8...Cooling system, 80...Coolant flow, 82...First coolant connection, 82...Second coolant connection, 9...Cooling channel structure, 90...Coolant channel, 91...First cooling section, 92...Second cooling section, 94...First inner wall, 95...Second inner wall, 96...Lateral inner wall.
Claims
1. A wireless charging module for charging the battery (5) of a vehicle (2), and / or supplying power to an electrical load of the vehicle (2), and / or delivering energy from the battery (5) of the vehicle (2), and / or delivering energy from an energy source of the vehicle (2), A first, in particular, magnetic subassembly (6) for receiving an oscillating electromagnetic field and converting it to an alternating current, A second, in particular, electronic subassembly (7) for receiving the alternating current and converting it into a current for charging the battery (5) or supplying power to the electrical load, The system includes a cooling system (8) for dissipating the heat generated by the two subassemblies (6, 7) during their operation by a flow of coolant (80). The cooling system (8) comprises a cooling channel structure (9) having at least one coolant channel (90) and at least two flow guiding elements (45) extending laterally with respect to the flow direction, A wireless charging module in which the width of the flow guidance element (45) is greater than the distance between the flow guidance elements (45).
2. The wireless charging module (4) according to claim 1, wherein the width of the flow guidance element (45) is at least 1.5 times, particularly at least 2 times, and particularly at least 3 times, the distance between the flow guidance elements (45).
3. The flow guiding element (45) receives the flow and has at least a substantially semicircular cross-section on its side surface (46) facing the flow. In particular, the wireless charging module (4) according to claim 1 or 2, having at least a substantially semicircular cross-section on its side (47) away from the flow.
4. The wireless charging module (4) according to claim 3, wherein the flow guidance element (45) has a circular cross-section.
5. The wireless charging module (4) according to claim 3, wherein the flow guidance element (45) has an elliptical or egg-shaped cross-section.
6. The flow guide element (45) is positioned in a curved section of the coolant channel (90), The length of the flow guiding element (45) in the flow direction is greater than the width of the flow guiding element (45) perpendicular to the flow direction. The wireless charging module (4) according to claim 3, wherein in the intermediate region between the flow guiding elements extending in the flow direction, the distance between the flow guiding elements (45) at different positions within the intermediate region is essentially the same.
7. The wireless charging module (4) according to claim 5 or 6, wherein the length of the flow guide element (45) in the flow direction is less than 2.5 times the width of the flow guide element (45) perpendicular to the flow direction, and in particular equal to at least approximately 2 times.
8. The wireless charging module (4) according to any one of claims 1 to 7, wherein the flow guide element (45) begins at a first inner wall (94) of the coolant channel (90) and extends to a second inner wall (95) on the opposite side, or at least substantially to the second inner wall (95).
9. The wireless charging module (4) according to any one of claims 1 to 8, wherein the flow guide element (45) is made of metal.
10. The wireless charging module (4) according to claim 9, wherein the flow guide element (45) is formed integrally with the inner wall of the coolant channel (90) which is made of metal.
11. The wireless charging module (4) according to claim 9, wherein the flow guide element (45) is inserted into the inner wall of the coolant channel (90) formed of a nonmetallic material and is guided to a heat transfer body positioned to receive heat from subassemblies (6, 7) that generate heat and are cooled during operation.
12. The wireless charging module (4) according to any one of claims 1 to 11, wherein the coolant channel (90) comprises at least one cooling section (91, 92), and the flow guide element (45) is positioned in the cooling section (91, 92) to dissipate heat from subassemblies (6, 7) that generate and are cooled during operation, in particular the magnetic subassembly (6) and the electronic subassembly (7).
13. The wireless charging module (4) according to any one of claims 1 to 12, wherein the cooling channel has an essentially rectangular cross-section, its extension along a first direction is hereafter referred to as the height, and its extension along a second direction is hereafter referred to as the width, the width being at least three times the height.
14. The cooling channel structure is positioned between at least one first portion (41) and a second portion (42), and one or more channels of the cooling channel structure (9) are formed by a plurality of recesses in the first portion (41) and / or the second portion (42). In particular, the wireless charging module (4) according to any one of claims 1 to 13, wherein the first portion (41) and / or the second portion (42) are plate-shaped or extend over a wide area.