An oil-immersed power module and charging system

Abstract

The application discloses an oil-immersed power module and a charging system. The oil-immersed power module comprises a shell, a power plate and at least one busbar, the shell is provided with a liquid inlet and a liquid outlet, the power plate is attached to the inner side of the shell, and the at least one busbar is vertically arranged on one side of the power plate and is provided with a plurality of oil through holes. The busbar is internally provided with a thick copper circuit layer. The busbar is internally provided with the thick copper circuit layer, so that the traditional copper busbar can enhance the current carrying capacity. The busbar separates the inside of the shell and is provided with the oil through holes, so that the insulating oil needs to pass through the oil through holes to reach both sides of the busbar, thereby realizing the guiding effect of the traditional busbar on the insulating oil. Therefore, only the busbar is used in the power module to replace the traditional busbar and the busbar, thereby effectively reducing the overall size of the power module.

Description

Technical Field

[0001] This application relates to the field of power module technology, and in particular to an oil-immersed power module and charging system. Background Technology

[0002] Currently, oil-cooled power modules generally adopt a discrete layout of air guide plates and busbars, such as... Figure 1 As shown, a guide plate is installed inside the power module housing, and holes are opened on the guide plate to guide the cooling oil. In addition, an electrical structure and a copper busbar are also installed in the middle of the power module housing to enhance the current carrying capacity.

[0003] The aforementioned guide plates and busbars are often stacked vertically within the power module, resulting in a large overall space occupied by the power module. Utility Model Content

[0004] The main purpose of this application is to provide an oil-immersed power module and charging system, which aims to solve the problem of large module space occupation caused by the vertical stacking of current guide plates and busbars in traditional power modules.

[0005] To achieve the above objectives, this application provides an oil-immersed power module, which includes a housing, a power board, and at least one manifold. The housing has an inlet and an outlet. The power board is attached to the inner side of the housing. At least one manifold is vertically disposed on one side of the power board and has multiple oil passage holes. The multiple manifolds are spaced apart. The manifold has a thick copper circuit layer inside and divides the interior of the housing into multiple chambers connected by the oil passage holes. The inlet and outlet are respectively connected to the two outermost chambers.

[0006] Optionally, there are two flow guide strips, which are spaced apart in the height direction of the housing; wherein, the two flow guide strips divide the interior of the housing into a liquid inlet chamber, an installation chamber and a liquid outlet chamber that are connected in sequence, the liquid inlet is connected to the liquid inlet chamber and the liquid outlet is connected to the liquid outlet chamber.

[0007] Optionally, the oil-immersed power module further includes guide ribs, which are disposed on the inner side of the housing and fit against the edge of the busbar to separate the chambers.

[0008] Optionally, the extension direction of the manifold guide strip is parallel to the power plate; and the density of the plurality of oil passage holes varies in a gradient manner along the extension direction of the manifold guide strip.

[0009] Optionally, the extension direction of the busbar is parallel to the power board; and the thickness of the thick copper circuit layer varies in a gradient along the extension direction of the busbar.

[0010] Optionally, the oil passage further includes a deformation ring; the deformation ring includes multiple deformation rings, which are correspondingly embedded in the inner circumference of the oil passage, and the deformation ring is made of a thermodeformable material.

[0011] Optionally, the oil-immersed power module further includes microfins disposed on the surface of the busbar.

[0012] Optionally, the power board is provided with a connection hole; the oil-immersed power module further includes a mounting foot, which is disposed on the side of the busbar facing the power board and passes through the connection hole.

[0013] Optionally, the mounting foot includes a stepped first part and a second part, with a stepped surface formed between the second part and the first part; wherein the second part passes through the connecting hole, and the stepped surface abuts against the side of the power plate facing the busbar.

[0014] To achieve the above objectives, this application also provides a charging system, which includes at least one charging interface, a power distribution device, at least two of the aforementioned oil-immersed power modules, and a controller. The power distribution device is electrically connected to each of the charging interfaces. Each oil-immersed power module is electrically connected to the power distribution device and is used to convert AC power from the power grid into DC power, which is then supplied to the charging interface through the power distribution device. The controller is electrically connected to the power distribution device and is used to acquire the required power of each of the charging interfaces. Based on the connection relationship of the controllable switches in the power distribution device and the required power, the controller sends a scheduling command to the power distribution device. The power distribution device is used to control the opening or closing of the controllable switches in response to the scheduling command, so as to distribute the output power of each of the oil-immersed power modules to each of the charging interfaces.

[0015] This application proposes an oil-immersed power module with a thick copper circuit layer inside the busbar, which enhances the current carrying capacity of the traditional copper busbar. The busbar separates the interior of the housing and has oil passage holes, so that insulating oil must pass through the oil passage holes to reach both sides of the busbar, thus achieving the function of the traditional guide plate for guiding the insulating oil. In this way, the power module can use only the busbar to replace the traditional guide plate and busbar, thereby effectively reducing the overall size of the power module. Attached Figure Description

[0016] To more clearly illustrate the prior art and the present invention, the accompanying drawings used in the description of the prior art and the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other drawings from the provided drawings without any creative effort.

[0017] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which this utility model can be implemented. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0018] Figure 1 This is a schematic diagram of the structure of the guide plate installed inside the charging module in a traditional solution.

[0019] Figure 2 This is a schematic diagram of the internal structure of an oil-immersed power module according to an embodiment of this application;

[0020] Figure 3 This is a schematic diagram of the flow guide strip structure in the embodiments of this application;

[0021] Figure 4 This is a schematic diagram of an overall charging system provided in an embodiment of this application.

[0022] In the diagram: 1. Power board; 2. Busbar guide strip; 21. Oil passage hole; 31. First part; 32. Second part; 110. Oil-immersed power module; 120. Charging interface; 130. Controller; 140. Power distribution device.

[0023] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0026] In this utility model, unless otherwise explicitly specified and limited, the terms "connection" and "fixation" should be interpreted broadly. For example, "fixation" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] Currently, oil-cooled power modules generally adopt a discrete layout of air guide plates and busbars, such as... Figure 1 As shown, a guide plate is installed inside the power module housing, and holes are opened on the guide plate to guide the cooling oil. In addition, an electrical structure and a copper busbar are also installed in the middle of the power module housing to enhance the current carrying capacity.

[0029] The aforementioned guide plates and busbars are often stacked vertically within the power module, resulting in a large overall space occupied by the power module.

[0030] In traditional solutions, there are usually two guide plates that are positioned opposite each other inside the power module housing. Taking the direction of gravity as the direction of the two guide plates, the two guide plates divide the inside of the power module housing into a liquid outlet area, an electrical area, and a liquid inlet area arranged from top to bottom. Various electrical structures and busbars are installed in the electrical area.

[0031] In addition, the longitudinal stacking of the busbar and the guide plate means that in the direction of gravity, the guide plate and the busbar occupy different positions at different heights, resulting in a relatively high overall height of the power module and a large space occupation.

[0032] The present application will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] Figure 1 This is a schematic diagram of the structure of the guide plate installed inside the charging module in a traditional solution. Figure 2 This is a schematic diagram of the internal structure of an oil-immersed power module according to an embodiment of this application; Figure 3 This is a schematic diagram of the flow guide strip structure in the embodiments of this application; Figure 4 This is a schematic diagram of an overall charging system provided in an embodiment of this application.

[0034] It should be understood that, Figure 2 The circuit structures shown, such as the secondary rectifier circuit, the anti-reverse circuit, and the output terminals, are only schematic diagrams and do not limit the circuit structures within the power module.

[0035] in addition, Figure 2 The flow guide strip 2 shown is mainly for illustrative purposes and does not represent the lateral length of the flow guide strip 2. Figure 2 As shown, it is short; here it should be the same as the width. Figure 1 In combination, this is equivalent to the traditional flow guide plate and busbar being combined and set together on the power board 1, and the inside of the power module housing is separated. In other words, except for the side connected to the power board, the sides of the busbar 2 should all be connected to and in contact with the inside of the housing.

[0036] refer to Figures 1-4 This application provides an oil-immersed power module, which may include a housing, a power board 1, and at least one manifold 2. The housing has an inlet and an outlet. The power board 1 is attached to the inner side of the housing. At least one manifold 2 is vertically disposed on one side of the power board 1 and has multiple oil passage holes 21. The multiple manifolds 2 are spaced apart. The manifold 2 has a thick copper circuit layer inside and divides the interior of the housing into multiple chambers connected by the oil passage holes 21. The inlet and outlet are respectively connected to the two outermost chambers.

[0037] The oil-immersed power module proposed in this application embodiment has a thick copper circuit layer inside the busbar 2, which can achieve the function of enhancing the current carrying capacity of traditional copper busbars. The busbar 2 separates the interior of the housing and has oil passage holes 21, so that the insulating oil must pass through the oil passage holes 21 to reach both sides of the busbar 2, thereby realizing the function of the traditional guide plate for guiding the insulating oil. In this way, the power module can use only the busbar 2 to replace the traditional guide plate and busbar, thereby effectively reducing the overall size of the power module.

[0038] The insulating oil is the cooling medium for the oil-immersed power module.

[0039] It should be understood that transforming the heat dissipation and airflow design from "separate superposition" to "synergistic coexistence" eliminates the independent installation space of traditional airflow guide plates, enables the reuse of heat dissipation and electrical structures, significantly compresses the vertical dimensions of the power module, facilitates the compact arrangement of power devices, and thus reduces the overall volume of the power module.

[0040] It should be noted that the circuit inside the thick copper circuit layer in the busbar 2 can avoid the oil passage hole 21; in addition, the power board 1 can be connected to the inside of the housing by bolts.

[0041] Both the power board 1 and the busbar 2 are PCB board structures and can be made of FR4 PCB substrate with high thermal conductivity. They are formed into a composite structure with thick inner copper circuit through a lamination process. The copper layer thickness meets the current carrying requirements. In this way, the consumption of precious metals is further reduced by optimizing the utilization rate of copper foil. The cost of injection molding or stamping molds for the flow channel can be eliminated.

[0042] Of course, the entire flow guide strip 2 can also be made of copper, with oil passage holes 21 provided.

[0043] It should be understood that multiple thick copper circuit layers can be stacked inside the busbar 2, and these multiple thick copper circuit layers can be effectively connected through through holes.

[0044] It should be noted that the busbar 2 should be located close to the edge of the power board 1.

[0045] In an exemplary embodiment, there are two flow guide strips 2, which are spaced apart in the height direction of the housing; wherein, the two flow guide strips 2 divide the interior of the housing into a liquid inlet chamber, an installation chamber and a liquid outlet chamber that are connected in sequence, with the liquid inlet connected to the liquid inlet chamber and the liquid outlet connected to the liquid outlet chamber.

[0046] It should be understood that at this time, the power board 1 spans the liquid inlet chamber, the installation chamber and the liquid outlet chamber. The two flow guide strips 2 installed on the power board 1 are the partitions between adjacent chambers. The electrical structure on the power board 1 is located in the installation chamber.

[0047] Specifically, the insulating oil enters the inlet chamber from the inlet of the housing, and reaches the mounting chamber through the oil passage 21 to dissipate heat from the electrical structure on the power board 1. After that, the insulating oil reaches the outlet chamber through the oil passage 21 and flows out from the outlet.

[0048] Taking the case where the inlet chamber is located below the outlet chamber as an example, the insulating oil flows from bottom to top through the installation chamber and finally reaches the outlet chamber. In this way, the two confluence guide strips 2 can guide the insulating oil, so that the insulating oil flows through all parts of the installation chamber for heat dissipation.

[0049] In an exemplary embodiment, the oil-immersed power module may further include guide ribs disposed on the inner side of the housing and abutting the edge of the busbar 2 to separate the chambers.

[0050] It should be understood that by fitting the guide ribs to the edge of the busbar 2, the sealing effect between the busbar 2 and the inner side of the housing can be further improved, reducing the flow of insulating oil through the gap between the busbar 2 and the housing, and further enhancing the flow guiding effect of the busbar 2.

[0051] refer to Figure 2 and Figure 3 In an exemplary embodiment, the extension direction of the manifold guide bar 2 is parallel to that of the power plate 1; and the density of the plurality of oil passage holes 21 varies in a gradient manner along the extension direction of the manifold guide bar 2.

[0052] Specifically, different components on the power board 1 have different heating powers. The area of ​​the current guide bar 2 near the component with high heating power is designated as the high-heat area, and the oil passage holes 21 are arranged in a high density. The area of ​​the current guide bar 2 near the component with low heating power is designated as the low-heat area, and the oil passage holes 21 are arranged in a high density. This creates a gradient guiding effect, which more rationally distributes the flow of insulating oil through the high-heat area and the low-heat area, uniformly dissipates heat, and achieves better heat dissipation.

[0053] For example, such as Figure 2 As shown, if the primary-side power devices generate a large amount of heat and the output electrolytic capacitor generates a small amount of heat, then the busbar 2 will... Figure 2 The density of the oil passage holes 21 in the left-middle region should be greater than that of the manifold guide strip 2. Figure 2 The arrangement density of oil passage holes 21 in the right-side region.

[0054] In an exemplary embodiment, the extension direction of the busbar 2 is parallel to that of the power board 1; and the thickness of the thick copper circuit layer varies in a gradient manner along the extension direction of the busbar 2.

[0055] Specifically, a thicker copper circuit layer can be added to the main current path area of ​​the busbar 2, while the thicker copper circuit layer can be thinned in other areas of the busbar 2. This results in a thicker copper circuit layer in the main current path area, which has a stronger current carrying capacity. The thicker copper circuit layer in other areas can be thinned, which effectively reduces manufacturing costs and balances the current carrying capacity of the busbar 2.

[0056] In an exemplary embodiment, the oil passage 21 further includes a deformation ring; the deformation ring includes a plurality of rings, which are correspondingly embedded in the inner circumference of the oil passage 21, and the deformation ring is a thermally deformable material.

[0057] The deformable ring is made of a thermo-deformable material, such as a shape memory alloy or a material with a large coefficient of thermal expansion. When the deformable ring is embedded in the inner circumference of the oil passage 21, the flow effect of the oil passage 21 is determined by the inner diameter of the deformable ring. If the internal temperature of the power module is not high, the deformable ring shrinks and the inner diameter becomes smaller, thereby accelerating the flow of insulating oil to impact the heating area. If the internal temperature of the power module is high, the deformable ring expands and the inner diameter becomes larger, thereby balancing heat dissipation and realizing the dynamic adjustment of the application aperture of the oil passage 21.

[0058] The actual diameter of the oil passage 21 refers to the inner diameter of the deformed ring.

[0059] In an exemplary embodiment, the oil-immersed power module may further include microfins disposed on the surface of the busbar 2.

[0060] Among them, the microfins are nano-coated microfins. The microfins can effectively increase the contact area between the busbar 2 and the insulating oil, thereby improving the heat exchange efficiency of the busbar 2 itself.

[0061] refer to Figure 2 and Figure 3 In an exemplary embodiment, the power board 1 is provided with a connection hole; the oil-immersed power module may also include a mounting foot, which is disposed on the side of the busbar 2 facing the power board 1 and passes through the connection hole.

[0062] The busbar 2 can be fixed to the power board 1 by inserting the mounting pin into the connection hole on the power board 1 and welding the mounting pin to the power board 1.

[0063] refer to Figure 2 and Figure 3 In an exemplary embodiment, the mounting foot may include a first portion 31 and a second portion 32 arranged in a stepped manner, and a stepped surface is formed between the second portion 32 and the first portion 31; wherein the second portion 32 is inserted into the connection hole, and the stepped surface abuts against the side of the power plate 1 facing the busbar 2.

[0064] Specifically, such as Figure 3As shown, both the first part 31 and the second part 32 can be cylindrical. The first part 31 is fixed to the side of the busbar 2, and the second part 32 is fixed to the end of the first part 31 away from the busbar 2. The first part 31 and the second part 32 are coaxially arranged, and the diameter of the second part 32 is smaller than the diameter of the first part 31. In this way, a stepped surface will be formed between the first part 31 and the second part 32. When the second part 32 is inserted into the connection hole, the stepped surface abuts against the power board 1, so that the busbar 2 and the side of the power board 1 facing the busbar 2 maintain a gap, forming isolation, effectively preventing additional interference between the circuit on the busbar 2 and the circuit on the power board 1.

[0065] In an exemplary embodiment, a temperature sensor or a flow sensor may also be embedded in the busbar 2, and the sensor detection data may be fed back to the control system through the busbar 2 and the built-in circuit on the power board 1, thereby dynamically adjusting the power of the external oil circulation pump of the oil-immersed power module and adjusting the flow rate of the insulating oil to adapt to the heat dissipation requirements under different operating conditions.

[0066] The specific temperature sensor or flow sensor can be embedded in the manifold guide strip 2 and connected to the circuit inside the manifold guide strip 2.

[0067] The temperature sensor is used to detect the temperature of the insulating oil in the vicinity, and the flow sensor is used to detect the flow rate of the oil passage 21.

[0068] refer to Figure 4 Based on the above embodiments, this application provides a charging system that may include at least one charging interface 120, a power distribution device 140, at least two of the aforementioned oil-immersed power modules 110, and a controller 130. The power distribution device 140 is electrically connected to each charging interface 120. The oil-immersed power modules 110 are electrically connected to the power distribution device 140 and are used to convert AC power from the power grid into DC power, which is then supplied to the charging interface 120 through the power distribution device 140. The controller 130 is electrically connected to the power distribution device 140 and is used to obtain the required power of each charging interface 120 and send a scheduling command to the power distribution device 140 based on the connection relationship of the controllable switches in the power distribution device 140 and the required power. The power distribution device 140 is used to control the opening or closing of the controllable switches in response to the scheduling command, so as to distribute the output power of each oil-immersed power module 110 to each charging interface 120.

[0069] In one optional implementation, the charging system provided in this application is an integrated DC charging pile, with the charging interface 120 used to connect the charging gun, and the charging gun being hung on the host of the charging system via the gun holder on the main body of the charging system.

[0070] In one optional implementation, the charging system provided in this application is a split-type DC charging pile. The charging system also includes multiple charging terminals. The charging interface 120 is used to connect the charging terminals. The charging terminals are set separately from the main body of the charging system. The charging terminals are equipped with a single charging gun or dual charging guns for outputting power to electric vehicles.

[0071] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. An oil-immersed power module, characterized in that, include: The casing has a liquid inlet and a liquid outlet; A power board (1) is attached to the inner side of the housing; At least one flow guide strip (2) is vertically disposed on one side of the power board (1) and has multiple oil passage holes (21), and multiple flow guide strips (2) are spaced apart; wherein, the flow guide strip (2) has a thick copper circuit layer inside, and the flow guide strip (2) divides the interior of the housing into multiple chambers connected by the oil passage holes (21), and the liquid inlet and the liquid outlet are respectively connected to the two outermost chambers.

2. The oil-immersed power module as described in claim 1, characterized in that, There are two flow guide strips (2) and they are spaced apart in the height direction of the housing; The two flow guide strips (2) divide the interior of the housing into a liquid inlet chamber, an installation chamber and a liquid outlet chamber that are connected in sequence. The liquid inlet is connected to the liquid inlet chamber and the liquid outlet is connected to the liquid outlet chamber.

3. The oil-immersed power module as described in claim 1, characterized in that, The extension direction of the busbar (2) is parallel to that of the power plate (1); In the extension direction of the confluence guide strip (2), the density of the plurality of oil passage holes (21) varies in a gradient manner.

4. The oil-immersed power module as described in claim 1, characterized in that, The oil passage (21) also includes a deformable ring; The deformable rings include multiple rings, which are correspondingly embedded in the inner circumference of the oil passage (21), and the deformable rings are made of thermodeformable material.

5. The oil-immersed power module as described in claim 1, characterized in that, The oil-immersed power module also includes: Guide ribs are provided on the inner side of the housing and fit against the edge of the confluence guide strip (2) to separate each of the chambers.

6. The oil-immersed power module as described in claim 1, characterized in that, The extension direction of the busbar (2) is parallel to that of the power plate (1); The thickness of the thick copper circuit layer varies in a gradient manner along the extension direction of the busbar (2).

7. The oil-immersed power module as described in claim 1, characterized in that, The oil-immersed power module also includes: Microfins are disposed on the surface of the flow guide strip (2).

8. The oil-immersed power module as described in claim 1, characterized in that, The power board (1) is provided with connection holes; the oil-immersed power module further includes: The mounting feet are located on the side of the busbar (2) facing the power board (1) and pass through the connection hole.

9. The oil-immersed power module as described in claim 8, characterized in that, The mounting foot includes a first part (31) and a second part (32) arranged in a stepped manner, and a stepped surface is formed between the second part (32) and the first part (31); The second part (32) is inserted into the connecting hole, and the stepped surface abuts against the side of the power plate (1) facing the busbar (2).

10. A charging system, characterized in that, include: At least one charging port (120); The power distribution device (140) is electrically connected to each of the charging interfaces (120); At least two oil-immersed power modules (110) as described in any one of claims 1 to 9 are electrically connected to the power distribution device (140), and the oil-immersed power modules (110) are used to convert AC power from the power grid into DC power and provide it to the charging interface (120) through the power distribution device (140). A controller (130) is electrically connected to the power distribution device (140). The controller (130) is used to obtain the required power of each of the charging interfaces (120) and send a scheduling command to the power distribution device (140) based on the connection relationship of the controllable switches in the power distribution device (140) and the required power of each interface. The power distribution device (140) is used to control the opening or closing of the controllable switches in response to the scheduling command, so as to distribute the output power of each of the oil-immersed power modules (110) to each of the charging interfaces (120).

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