Wireless charging module comprising a cooling system

Abstract

The invention relates to a wireless charging module (4) which is used to charge a battery (5) of a vehicle (2), said charging module comprising ○ a first, in particular magnetic, assembly (6) for receiving an oscillating electromagnetic field and converting said field into an alternating electric current; ○ a second, in particular electronic, assembly (7) for receiving the alternating electric current and converting said current into an electric current for charging the battery (5) or for supplying power to the consumer; ○ a cooling system (8) for dissipating heat, that is generated by the two assemblies (6, 7) during their operation, by means of a coolant flow (80) between a first coolant connection (81) and a second coolant connection (82) of the cooling system (8); ○ wherein the cooling system (8) has a cooling channel structure (9) with at least one coolant channel (90) and with at least two cooling portions (91, 92). The two cooling portions (91, 92) have different shapes in order to dissipate a higher heat flow in the second cooling portion (92) than in the first cooling portion (91).

Description

[0001] WIRELESS CHARGING MODULE WITH COOLING SYSTEM

[0002] The present invention relates to a wireless charging module for charging a battery or powering a consumer of a vehicle. 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 being implemented as inductive charging systems (ICS). Wired AC chargers are typically integrated into electric vehicles and are also referred to as on-board chargers. 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 electromagnetic interaction between the GPM and the CPM enables energy transfer from the GPM to the CPM and vice versa, and the CPM is, in turn, used to charge an electric vehicle's battery. Wireless charging systems are often more convenient for the user, as no manual intervention is typically required to initiate battery charging, other than parking the vehicle over the GPM.

[0003] The wireless charging module according to the invention can be used in particular for charging a high-voltage battery or for storing a consumer device of a vehicle. In this case, it can be referred to as a car pad module (CPM). This can receive an oscillating magnetic field from an external transmitter, which can be referred to as a ground pad module (GPM). The CPM converts the oscillating electromagnetic, predominantly magnetic, field into an alternating current, which is converted (typically rectified) and thus becomes a charging current (typically direct current) used to charge the battery or power the consumer.

[0004] The wireless charging module can also be referred to as a power conversion assembly. It is used to convert the electromagnetic power of an oscillating electromagnetic field into electrical power, an electric current, or an available electric current, for charging an electrical storage device or powering an electrical load.

[0005] Regarding cooling, it is important to understand that a CPM can have two areas of heat generation: an electronic assembly (power electronics), which generates a lot of heat but is concentrated in certain places on the device and has a relatively high density of heat-generating elements there, and a magnetic assembly (coil and ferrite), which generates less heat and is relatively spatially distributed, i.e. with a low density of heat-generating elements.

[0006] Previous cooling systems for CPMs are not well-suited to these circumstances and are relatively difficult to manufacture and therefore expensive. The object of the invention is therefore to create a wireless charging module of the type mentioned above that eliminates the aforementioned disadvantages.

[0007] This problem is solved by a wireless charging module having the features of patent claim 1.

[0008] The wireless charging module is used to charge a battery and / or power a vehicle's consumer. It can be used in addition to or as an alternative to supplying electrical energy from the vehicle. It features:

[0009] • a first, in particular magnetic, assembly for receiving an oscillating electromagnetic field and converting it into an alternating electrical current;

[0010] • a second, in particular electronic, assembly for receiving the alternating electrical current and converting it into an electrical current for charging the battery or for supplying the consumer,

[0011] • a cooling system for dissipating heat generated by the two assemblies during their operation by a coolant flow between a first coolant port and a second coolant port of the cooling system.

[0012] The cooling system has a cooling channel structure with at least one coolant channel and at least two cooling sections:

[0013] • at least one first cooling section arranged to dissipate heat from the magnetic assembly, and

[0014] • at least one second cooling section arranged to dissipate heat at least from the electronic assembly,

[0015] The two cooling sections are shaped differently in order to dissipate a higher heat flow in the second cooling section than in the first cooling section. The first cooling section is therefore used to dissipate heat generated by the magnetic assembly during its operation, and the second cooling section is used to dissipate heat generated by the electronic assembly during its operation. By designing the two cooling sections to dissipate different heat flows, i.e. different amounts of heat per unit of time, the operation of the cooling system can be optimized according to the different amounts of heat generated from the two assemblies. This means that the coolant flow is distributed between the two cooling sections through the cooling channel structure so that at least approximately a maximum heat flow can be dissipated from both assemblies.

[0016] The fact that the cooling system has the coolant flow between the first coolant connection and the second coolant connection means that the cooling takes place through a single coolant flow, which can be divided into different parallel sections and / or can be guided sequentially through cooling sections with different properties.

[0017] In embodiments, the cooling channel structure is arranged between at least a first part and a second part, and one or more channels of the cooling channel structure are formed by recesses in the first part and / or the second part. In particular, the first part and / or the second part are plate-like or flat.

[0018] The first part and the second part each form a half-shell, which when placed together form the cooling channel structure with one or more coolant channels.

[0019] In some embodiments, the first and second cooling sections are arranged, at least in some regions, on mutually parallel coolant channels. In some embodiments, the first and second cooling sections are arranged at successive locations along the same coolant channel in the flow direction.

[0020] Therefore, there can be two or more cooling sections. If there is only one coolant channel, the cooling sections are arranged along this coolant channel. If there are two or more coolant channels, the cooling sections can be arranged along different coolant channels.

[0021] In embodiments, the first and second cooling sections have different wall structures. In particular, it is the case that

[0022] • one, in particular the first, cooling section has a smooth wall and the other, in particular the second, cooling section has a structured wall; or

[0023] • one, in particular the first, cooling section has a structured wall and the other, in particular the second, cooling section has a smooth wall; or

[0024] • one, in particular the first, cooling section has a structured wall and the other, in particular the second, cooling section has a differently structured wall.

[0025] A wall can be structured differently by varying the density of similarly shaped obstacles or swirl structures. In embodiments, regions with different heat dissipation requirements are located along a coolant channel, and correspondingly, associated cooling sections have similarly shaped swirl structures but with different densities.

[0026] In embodiments, the cooling channel structure comprises at least two coolant channels running parallel to each other, and these are designed to carry different proportions of the coolant flow. In particular, a coolant flow passing through the first cooling section is less than half, one-third, one-quarter, or one-fifth of the coolant flow passing through the second cooling section.

[0027] This allows the coolant flow to be distributed between the two cooling sections according to the amount of heat to be dissipated. This can be achieved, for example, by having the two coolant channels with different flow cross-sections and / or flow resistances, and / or by a geometry of branching areas where the coolant flow—which is routed from the first coolant connection or the second coolant connection to the two parallel coolant channels—is distributed between the coolant channels.

[0028] The ratio of the coolant flows is to be understood during operation of the charging module at a nominal value of the total coolant flow, corresponding to a nominal operating power of the charging module.

[0029] In embodiments, at least one of the cooling sections has structures on at least one channel wall for swirling the coolant flow. In particular, the structures are integrally formed on the channel wall.

[0030] In embodiments, structures in the region of the at least one cooling section form obstacles projecting into the coolant channel, which reduce the flow cross-section of the coolant channel compared to adjacent sections.

[0031] In embodiments, the structures divide the coolant channel into two or more sub-channels with parallel flows,

[0032] • particularly in sub-channels whose shape deviates from a straight line or a course with constant curvature,

[0033] • in particular in sub-channels with a wavy, zigzag, or meandering course. In embodiments, at least one of the first part and the second part forms a supporting structure that supports at least one of the magnetic and electronic components.

[0034] In embodiments, at least one of

[0035] • the magnetic assembly is mounted adjacent to the first cooling section, and optionally also adjacent to the second cooling section, on the first part or on the second part;

[0036] • the electronic assembly is mounted adjacent to the second cooling section, on the first part or on the second part.

[0037] Further preferred embodiments emerge from the dependent patent claims.

[0038] 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:

[0039] Figure 1 shows a garage with a vehicle on a wireless charging station;

[0040] Figure 2 shows a wireless charging station and a wireless charger;

[0041] Figure 3 a wireless charger;

[0042] Figure 4 shows a cross-section through a wireless charger;

[0043] Figure 5 shows the shape of a cooling channel structure in a cooling system;

[0044] Figure 6 shows a partially opened wireless charger; and

[0045] Figure 7-8 different forms of structured wall structures.

[0046] The reference symbols used in the drawings and their meanings are summarized in the list of reference symbols. In general, identical parts are provided with identical reference symbols throughout the figures. Figure 1 shows a plan view of a garage 1 in which a vehicle 2 is parked above a wireless charging station 3 located outside the vehicle 2 and having a transmitter for transmitting an oscillating magnetic field. The charging station 3 is visible because the vehicle 2 is shown transparently. This charging solution is very convenient and saves the driver from having to plug and unplug a charging cable.

[0047] Figure 2 is an enlargement of Figure 1 and shows the wireless charging station 3 and a wireless charger 4 "floating" above the charging station 3 for charging a high-voltage battery 5 of the vehicle 2. The charger 4 is built into the vehicle, meaning the rest of the vehicle is not visible in this view. Figure 3 shows a perspective view of the charger 4.

[0048] Figure 4 shows a schematic cross-section through a wireless charger 4, which can also be referred to as a wireless charging module. A first part 41 and a second part 42 form a supporting structure for the other components described. The first part 41 and / or second part 42 can themselves be composed of several individual parts. A housing (not shown) can also be present. An electronic assembly 7 is arranged on the first part 41. This leads to relatively high waste heat in a relatively small space. A magnetic assembly 6 is arranged on or in the second part 42. This assembly has coil conductors 62 and ferrite elements 61. These, distributed over a larger space, lead to comparatively lower waste heat.

[0049] Between the first part 41 and the second part 42, coolant channels 90 of a cooling channel structure 9 are formed by recesses in one or both of these parts. The coolant channels 90 can be sealed by sealing elements 49. The coolant channels 90 comprise a first cooling section 91, which primarily cools parts of the magnetic assembly 6, and a second cooling section 92, which cools the electronic assembly 7 and, in this embodiment, also parts of the magnetic assembly 6. The second cooling section 92 is therefore designed to dissipate a larger amount of heat per unit of time than the first cooling section 91.

[0050] To achieve this diverse heat dissipation with a shared coolant supply, various approaches are possible. These can be implemented individually or in combination:

[0051] • Coolant channels 90 can be provided that run parallel to one another and carry coolant flows of different sizes. To achieve these different coolant flows, the coolant channels 90 can have different hydraulic resistances, in particular different cross-sections. Furthermore, branches to the coolant channels can be shaped to achieve a desired distribution of the coolant flow 80.

[0052] • Cooling sections with different heat transfer properties to the channel wall may be present. Such different cooling sections can be arranged serially in the same coolant channel 90. They can also be arranged in parallel coolant channels 90.

[0053] The cooling channel structure 9, together with a first coolant connection 81 and a second coolant connection 82, forms a cooling system 8 of the wireless charger 4. Figure 5 shows the shape of a cooling channel structure 9 in a cooling system 8. Omitting the shape of the surrounding elements, only the shape of the cavities of the cooling system 8 is shown in a wireframe representation. The cooling channel structure 9 in Figure 5 has two parallel coolant channels, the first of which forms a first cooling section 91 and the second of which forms a second cooling section 92. The first cooling section 91 has a smaller cross-section and a smaller first coolant flow 80a than the second cooling section 92 with a larger second coolant flow 80b. This cooling channel structure 9 and the surrounding elements can have a cross-section as in Figure 4 (wherein the structured wall structure 44 is not shown in Figure 5).

[0054] In embodiments, the hydraulic resistances of parallel coolant channels 90 and / or the branches are designed such that the distribution of the coolant flow 80 between the two coolant channels 90 is the same regardless of the flow direction.

[0055] The shape design at the junction between the first cooling section 91 and the second cooling section 92 allows the distribution of the coolant flow 80 between the two to be controlled. The channels have smooth wall structures 43, meaning the walls of the channels are essentially smooth and do not cause turbulence in the coolant flow 80.

[0056] Figure 6 shows a partially opened wireless charger 4, with the second part 42 and the magnetic assembly 6 and sealing elements 49 removed. The complete wireless charger 4 can have a cross-section as in Figure 4. The first cooling section 91 and the second cooling section 92 are arranged one after the other in the coolant channel and are sequentially flowed through by the same coolant stream 80. As already mentioned, the waste heat from the electronic assembly 7 is dissipated in the second cooling section 92. For this purpose, swirling structures are provided, here cylindrical projections on the channel wall formed by the first part 41. To adapt to different amounts of waste heat within the electronic assembly 7, the swirling structures are arranged with a higher density in a first region 45a than in a second region 45b.

[0057] Figures 7 and 8 show various forms of structured wall structures 44. The structured wall structures 44 have obstacles or swirling structures 45 that swirl the coolant flow 80 and thereby improve heat transfer to the channel wall and to the swirling structures 45 themselves. The swirling structures 45 can be formed on the channel wall, i.e., integrally formed with the channel wall, to improve heat transfer to the channel wall. Alternatively, they can be connected to the channel wall with a material bond.

[0058] In Figure 7, the swirling structures 45 are projections that protrude into the coolant flow 80. The projections can be cylindrical, in particular circular-cylindrical. By adjusting the density of the similarly shaped projections, i.e., the number of projections per unit area of ​​the channel wall, a cooling section can be adapted to the amount of heat to be dissipated.

[0059] In Figure 8, the swirling structures 45 form parallel sub-channels 93 with a wavy or zigzag-shaped course.

[0060] LIST OF REFERENCE SYMBOLS

[0061] 1 garage 2 vehicles

[0062] 3 Charging station 4 Wireless charger 41 First part 42 Second part 43 Smooth wall structure

[0063] 44 structured wall structure 45 swirl structure 49 sealing element 5 battery 6 magnetic assembly

[0064] 61 Ferrite elements 62 Coil conductors 7 Electronic assembly

[0065] 8 Cooling system 80 Coolant flow 81 First coolant connection 82 Second coolant connection 9 Cooling channel structure Coolant channel First cooling section Second cooling section Sub-channel

Claims

PATENT CLAIMS 1. Wireless charging module for charging a battery (5) of a vehicle (2) and / or for supplying a consumer of the vehicle (2) and / or for delivering energy from the battery (5) of the vehicle (2) and / or for delivering energy from an energy source of the vehicle (2), with • a first, in particular magnetic, assembly (6) for receiving an oscillating electromagnetic field and converting it into an alternating electrical current; • a second, in particular electronic, assembly (7) for receiving the alternating electrical current and converting it into an electrical current for charging the battery (5) or for supplying the consumer, • a cooling system (8) for dissipating heat generated by the two assemblies (6, 7) during their operation by means of a coolant flow (80) between a first coolant connection (81) and a second coolant connection (82) of the cooling system (8); • wherein the cooling system (8) has a cooling channel structure (9) with at least one coolant channel (90) and with at least two cooling sections (91, 92), o at least one first cooling section (91) which is arranged to dissipate heat from the magnetic assembly (6), and o at least one second cooling section (92) which is arranged to dissipate heat at least from the electronic assembly (7), wherein the two cooling sections (91, 92) are shaped differently in order to dissipate a higher heat flow in the second cooling section (92) than in the first cooling section (91).

2. Wireless charging module (4) according to claim 1, wherein the cooling channel structure (9) is arranged between at least a first part (41) and a second part (42) and one or more channels (90) of the cooling channel structure (9) are formed by recesses in the first part (41) and / or in the second part (42), in particular wherein the first part (41) and / or the second part (part 42) are plate-like or flat.

3. Wireless charging module (4) according to one of the preceding claims, wherein the first and the second cooling section (91, 92) are arranged at least in regions on coolant channels (90) running parallel to one another.

4. Wireless charging module (4) according to one of the preceding claims, wherein the first and second cooling sections (91, 92) are arranged at successive locations in the flow direction along the same coolant channel (90).

5. Wireless charging module (4) according to one of the preceding claims, wherein the first and the second cooling section (91, 92) have different wall structures, in particular • wherein the one, in particular the first, cooling section (91) has a smooth wall (43) and the other, in particular the second, cooling section (92) has a structured wall (44); or • wherein one, in particular the first, cooling section (91) has a structured wall (44) and the other, in particular the second, cooling section (92) has a smooth wall (43); or • wherein the one, in particular the first, cooling section (91) has a structured wall (44) and the other, in particular the second, cooling section (92) has a differently structured wall (44).

6. Wireless charging module (4) according to one of the preceding claims, wherein the cooling channel structure (9) has at least two coolant channels (90) running parallel to one another, and these are designed to guide different proportions of the coolant flow (80), in particular wherein a coolant flow (80a) leading through the first cooling section (91) is less than half or one third or one quarter or one fifth of the coolant flow (80b) leading through the second cooling section (92).

7. Wireless charging module (4) according to one of the preceding claims, wherein at least one of the cooling sections (91, 92) has structures (45) on at least one channel wall for swirling the coolant flow, in particular wherein the structures are integrally formed on the channel wall.

8. Wireless charging module (4) according to claim 7, wherein the structures in the region of the at least one cooling section (91, 92) form obstacles projecting into the coolant channel (90) which reduce the flow cross-section of the coolant channel (90) compared to adjacent sections.

9. Wireless charging module (4) according to claim 7 or 8, wherein the structures divide the coolant channel (90) into two or more sub-channels (93) with parallel flows, in particular into sub-channels (93) whose shape deviates from a straight line or from a course with constant curvature, in particular into sub-channels (93) with a wavy, zigzag or meandering course.

10. Wireless charging module (4) according to one of the preceding claims in Dependent on claim 2, wherein at least one of the first part (41) and the second part (42) forms a supporting structure which supports at least one of the magnetic assembly (6) and the electronic assembly (7).

11. Wireless charging module (4) according to one of the preceding claims, wherein at least one is the case of • the magnetic assembly (6) is mounted adjacent to the first cooling section (91), and optionally also adjacent to the second cooling section (92), on the first part (41) or on the second part (42); • the electronic assembly (7) is mounted adjacent to the second cooling section (92), on the first part (41) or on the second part (42).

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