A power module and a power conversion device

Abstract

This application discloses a power module and a power conversion device. The solution includes a power device and a housing. The power device includes a power device body and terminals. The power device body is encapsulated within the housing, and the terminals extend out of the housing. The housing includes a liquid inlet, a liquid outlet, and a cooling channel. Both the liquid inlet and the liquid outlet are connected to the cooling channel, and the power device body is located within the cooling channel. Coolant enters the cooling channel through the liquid inlet and directly contacts the power device body, then flows out through the liquid outlet. Because the coolant directly contacts the power device body, it reduces thermal resistance and improves the heat dissipation efficiency of the power device, thereby increasing the utilization rate of the power device.

Description

Technical Field

[0001] This application relates to the field of electronic device technology, and in particular to a power module and a power conversion device. Background Technology

[0002] An insulated gate bipolar transistor (IGBT) is a power device that combines the low on-state voltage drop of a power transistor (GTR) with the high input impedance of a field-effect transistor (MOSFET). It is widely used in high-voltage, high-current energy conversion and control applications.

[0003] Currently, IGBTs mostly use indirect heat dissipation, where the IGBT is packaged in a housing and then mounted on a heat sink. This results in high thermal resistance and insufficient heat dissipation, leading to low IGBT utilization efficiency, increased usage, and higher system costs.

[0004] Therefore, how to improve the utilization rate of power devices has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] This application proposes a power module and a power conversion device to improve the utilization rate of power devices.

[0006] To achieve the above objectives, this application discloses the following technical solutions:

[0007] In a first aspect, this application provides a power module, characterized in that it includes a power device and a housing, the power device including a power device body and terminals, the power device body being encapsulated within the housing, and the terminals extending out of the housing;

[0008] The housing includes a liquid inlet, a liquid outlet, and a cooling channel. Both the liquid inlet and the liquid outlet are connected to the cooling channel, and the power device body is located inside the cooling channel.

[0009] In some embodiments, the power module further includes a substrate, which is encapsulated within a housing and disposed on the substrate.

[0010] In some embodiments, the power module further includes a support member that is supported between the substrate and the housing; cooling channels are distributed on both sides of the substrate in the thickness direction of the substrate and with the substrate as the boundary.

[0011] In some embodiments, the inlet and outlet are located on the same side of the housing or on opposite sides of the housing.

[0012] In some embodiments, a partition is provided inside the housing, one end of which is connected to the inner wall of the housing, and the other end of which has a gap with the inner wall of the housing. The partition divides the cooling channel into a circulation channel from the liquid inlet to the liquid outlet.

[0013] In some embodiments, the housing includes a first housing and a second housing, with the first housing disposed at an opening of the second housing; a seal is provided between the first housing and the second housing.

[0014] In some embodiments, there are at least two groups of power devices, and the at least two groups of power devices share a liquid inlet and a liquid outlet, with at least two power devices in each group.

[0015] In some embodiments, the housing includes at least two cooling channels and a connecting hole, each cooling channel is provided with a set of power devices, and adjacent cooling channels are connected through the connecting hole.

[0016] In some embodiments, the housing is filled with coolant, which is an insulating liquid.

[0017] Secondly, this application provides a power conversion device, including a power module as described in any of the above.

[0018] As can be seen from the above technical solution, the coolant enters the cooling channel through the inlet and comes into direct contact with the power device body, and then flows out through the outlet. Because the coolant is in direct contact with the power device body, it reduces thermal resistance and improves the heat dissipation efficiency of the power device, thereby increasing the utilization rate of the power device. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort, and this application can be applied to other similar scenarios based on the provided drawings. Unless obvious from the linguistic context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0020] Figures 1 to 5 Cross-sectional views of five power modules provided in the embodiments of this application;

[0021] Figure 6 A perspective view of the power module provided in the embodiments of this application, with the first housing hidden;

[0022] Figures 7 to 12 A schematic diagram of the circulation channels of six power modules provided in the embodiments of this application;

[0023] In the diagram: 1-Power device; 2-Housing; 2a-First housing; 2b-Second housing;

[0024] 11-Power device body; 12-Terminal; 13-Substrate; 14-Support member; 12a-Control terminal; 12b-Power terminal;

[0025] 21-Inlet; 22-Outlet; 23-Cooling channel; 24-Seal; 25-Fixing hole; 26-Baffle; 27-Connecting hole. Detailed Implementation

[0026] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. The described embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application.

[0027] To achieve the above objectives, this application discloses the following technical solutions:

[0028] See Figure 1 This application provides a power module, including a power device 1 and a housing 2. The power device 1 includes a power device body 11 and terminals 12. The power device body 11 is encapsulated in the housing 2, and the terminals 12 extend out of the housing 2. The housing 2 includes a liquid inlet 21, a liquid outlet 22, and a cooling channel 23. Both the liquid inlet 21 and the liquid outlet 22 are connected to the cooling channel 23, and the power device body 11 is located in the cooling channel 23.

[0029] In the power module described in this application, the coolant enters the cooling channel 23 through the inlet 21 and comes into direct contact with the power device body 11, and then flows out through the outlet 22. Because the coolant directly contacts the power device body 11, it reduces thermal resistance and improves the heat dissipation efficiency of the power device 1, thereby increasing the utilization rate of the power module.

[0030] The aforementioned power devices can be insulated gate bipolar transistors (IGBTs), integrated gate-commutated thyristors (IGCTs), etc.

[0031] Furthermore, direct contact between the coolant and the power device body 11 increases the effective heat dissipation area of ​​the power device body 11, resulting in a more uniform temperature distribution on the surface of the power device body 11 and extending the service life of the power module. The volumetric heat capacity C of the coolant is much higher than that of air (e.g., water's C≈4180J / (kg·kg·pK), while air's volumetric heat capacity is only 1005J / (kg·kg·pK)), allowing it to absorb more heat. Under dynamic operating conditions, direct liquid cooling provides a faster transient thermal response, preventing the device from overheating due to sudden power surges. The high heat dissipation capacity of direct liquid cooling allows the power module to operate at higher power densities, driving the miniaturization of power modules.

[0032] It should be noted that the aforementioned housing 2 encapsulates one or at least two power devices 1. In the case of at least two power devices 1, the at least two power devices 1 can be connected using conventional connection methods in the art, such as parallel connection, series connection, half-bridge connection, full-bridge connection, multi-level topology, modular series / parallel connection, matrix connection, etc.

[0033] The aforementioned power device body 11 is directly arranged on the housing 2, such as Figure 1 As shown, in some embodiments of this application, the power device body 11 is indirectly arranged on the housing 2, such as... Figure 2 As shown, in this example, the power module also includes a substrate 13, which is encapsulated in the housing 2, and the power device body 11 is disposed on the substrate 13.

[0034] The main functions of the substrate 13 include mechanical support, electrical insulation, heat conduction and heat dissipation, and circuit interconnection. The substrate 13 is usually composed of multiple layers of materials, such as direct copper-clad ceramic substrate, active metal brazing substrate, or metal substrate.

[0035] In the figure, multiple power device bodies 11 are arranged on a substrate. The circuit on the substrate 13 can be selected according to the connection method of the multiple power device bodies 11 to realize the connection of multiple power devices 1. For example, the circuit on the substrate 13 can realize the parallel connection, series connection, half bridge, full bridge, multi-level topology, modular series / parallel connection, matrix connection, etc. of multiple power devices 1.

[0036] See Figure 3 and Figure 4The power module also includes a support member 14, which is supported between the substrate 13 and the housing 2. Cooling channels 23 are distributed on both sides of the substrate 13 along the thickness direction of the housing 2, with the substrate 13 as the boundary. As shown in the figure, by setting the support member 14, a space is formed between the substrate 13 and the housing 2, allowing coolant to flow above the power device body 11 and below the substrate 13. The coolant above directly contacts the power device body 11, while the coolant below conducts heat between the substrate 13 and the power device body 11, thereby further increasing the effective heat dissipation area of ​​the power device body 11.

[0037] The aforementioned support member 14 can be a column, protrusion, etc. The support member 14 can be integrally formed with the inner wall of the shell 2, or it can be connected by bonding.

[0038] The power device 1 has terminals 12, including a power terminal 12b and a control terminal 12a, which are inserted into the housing 2 via injection molding. The power device 1 has three terminals: a gate (G), a collector (C), and an emitter (E). The control terminal 12a is the gate and is primarily responsible for controlling the switch, while the power terminal 12b is both the collector and emitter and is primarily responsible for switching the main current on and off.

[0039] Since the aforementioned terminal 12 is partially in contact with cooling, in order to reduce the probability of corrosion of the power terminal 12b and the control terminal 12a, an anti-corrosion layer is provided on the surface of the power terminal 12b and the control terminal 12a.

[0040] See Figure 5 and Figure 6 Since terminal 12 extends out of housing 2 to connect with external circuits, terminal 12 can be installed inside housing 2 by injection molding to improve the sealing performance between housing 2 and terminal 12; or in some examples, a hole for terminal 12 to pass through is pre-set on housing 2 and filled and sealed by sealant. As long as the sealing performance between terminal 12 and housing 2 can be guaranteed, it is within the protection scope of this application.

[0041] Additionally, it should be noted that the function of the housing 2 is to encapsulate the power device 1. Therefore, the housing 2 can be a closed structure. For example, the power device 1 can be encapsulated according to requirements using injection molding or 3D printing technology. Any structure that can encapsulate the power device 1 can be understood as the housing 2.

[0042] In the diagram, housing 2 includes a first housing 2a and a second housing 2b, with the first housing 2a positioned at the opening of the second housing 2b. The first housing 2a and the second housing 2b can be connected in a non-detachable manner or in a detachable manner. During assembly, the power device 1 is first placed inside the second housing 2b, and then the first housing 2a is installed at the opening of the second housing 2b. The connection between the second housing 2b and the first housing 2a can be achieved through snap-fitting, fusion bonding, adhesive bonding, etc.

[0043] To improve the sealing performance at the mating point of the first housing 2a and the second housing 2b, a sealing element 24 is provided between the first housing 2a and the second housing 2b.

[0044] To facilitate the installation of the housing 2, in some examples of this application, the housing 2 also includes a fixing hole 25 through which the power module can be fixedly installed.

[0045] The above mainly describes the structure of the power device 1 and the housing 2. Additionally, this application can further describe the relationship between the liquid inlet 21, the liquid outlet 22, and the cooling channel 23 in conjunction with the accompanying drawings. In some embodiments, the liquid inlet 21 and the liquid outlet 22 are located on opposite sides of the housing 2, such as... Figure 7 As shown, or the inlet 21 and outlet 22 are located on the same side of the housing 2, such as... Figure 8 As shown.

[0046] To improve heat dissipation efficiency, some embodiments of this application may also increase the turbulence of the coolant entering the cooling channel 23 by reducing the flow area of ​​the coolant, thereby improving the uniformity of temperature distribution within the cooling channel 23. For example, a serpentine structure, a U-shaped structure, etc., may be used.

[0047] For this purpose, a partition 26 is provided inside the housing 2. One end of the partition 26 is connected to the inner wall of the housing 2, and the other end of the partition 26 has a gap with the inner wall of the housing 2. The partition 26 divides the cooling channel 23 into a circulating channel from the liquid inlet 21 to the liquid outlet 22, such as... Figures 8 to 10 As shown.

[0048] in, Figure 8 In the structure shown, the liquid inlet 21 and the liquid outlet 22 are located on the same side of the housing 2, and an odd number of partitions 26 are provided inside the housing 2.

[0049] Figure 9 In the structure shown, with the inlet 21 and outlet 22 located on opposite sides of the housing 2, an even number of partitions 26 are provided inside the housing 2.

[0050] Figure 10 In the structure shown, with the inlet 21 and outlet 22 located on adjacent sides of the housing 2, an odd number of partitions 26 are provided inside the housing 2.

[0051] The number and length of the aforementioned partitions 26 can be adjusted according to heat dissipation requirements.

[0052] Figures 1 to 10 The power module described includes a group of power devices 1. The group of power devices 1 shown in the figure includes eight power devices 1, with four power devices 1 arranged in the same row.

[0053] In some examples of this application, the power module may include at least two groups of power devices 1, which share a common inlet 21 and outlet 22. Each group of power devices 1 contains at least two power devices 1. Figure 11 and Figure 12 As shown in the figure, the power module includes two groups of power devices 1, and each group of power devices 1 includes eight power devices 1.

[0054] At least two sets of power devices 1 are arranged in the same cooling channel 23 within the housing 2, or in different cooling channels 23. In the figure, the two sets of power devices 1 are located in different cooling channels 23.

[0055] Each group of power devices 1 may have its own set of liquid inlet 21, liquid outlet 22 and cooling channel 23, or each group of power devices 1 may share the liquid inlet 21 and liquid outlet 22, while each group has its own cooling channel 23.

[0056] When at least two sets of power devices 1 share the liquid inlet 21 and the liquid outlet 22, the housing 2 includes at least two cooling channels 23 and a connecting hole 27. Each cooling channel 23 is provided with a set of power devices 1, and adjacent cooling channels 23 are connected through the connecting hole 27.

[0057] in, Figure 11 The two sets of power devices 1 share a common liquid inlet 21 and liquid outlet 22, and the liquid inlet 21 and liquid outlet 22 are located on opposite sides. Figure 12 The two sets of power devices 1 share a liquid inlet 21 and a liquid outlet 22, and the liquid inlet 21 and the liquid outlet 22 are located on the same side.

[0058] It should be noted that the aforementioned coolant power module may also include coolant filled within the housing 2. The coolant flows into the cooling channel 23 from the inlet 21 and flows out from the outlet 22. The coolant is an insulating liquid. The coolant can be sealed within the cooling channel 23 and can also be refilled during use. The coolant is deionized water or pure water. This coolant can be in direct contact with conductors. Furthermore, the insulating liquid contains substances that lower the freezing point, allowing the liquid to operate at low temperatures without freezing. The two sets of power modules share a single heat dissipation channel, maximizing liquid cooling efficiency.

[0059] This application discloses a power conversion device, including a power module as described in any of the above claims. Since the power module has the aforementioned beneficial effects, the power conversion device including the power module also has corresponding effects, which will not be elaborated further here.

[0060] In addition, the power conversion device of this application can be an inverter, a frequency converter, a buck converter, a boost converter, etc.

[0061] In the above context, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0062] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. "And / or" in this article is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone.

[0063] It should be noted that, for ease of description, only the parts relevant to the application are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0064] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed, and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. The scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described application concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A power module, characterized in that, It includes a power device (1) and a housing (2). The power device (1) includes a power device body (11) and a terminal (12). The power device body (11) is encapsulated in the housing (2), and the terminal (12) extends out of the housing (2). The housing (2) includes a liquid inlet (21), a liquid outlet (22) and a cooling channel (23). The liquid inlet (21) and the liquid outlet (22) are both connected to the cooling channel (23). The power device body (11) is located inside the cooling channel (23).

2. The power module as described in claim 1, characterized in that, The power module also includes a substrate (13), which is encapsulated within the housing (2).

3. The power module as described in claim 2, characterized in that, The power module also includes a support member (14), which is supported between the substrate (13) and the housing (2); in the thickness direction of the substrate (13) and with the substrate (13) as the boundary, the cooling channels (23) are distributed on both sides of the substrate (13).

4. The power module as described in claim 1, characterized in that, The inlet (21) and the outlet (22) are located on the same side of the housing (2) or on opposite sides of the housing (2).

5. The power module as described in any one of claims 1-4, characterized in that, A partition (26) is provided inside the housing (2). One end of the partition (26) is connected to the inner wall of the housing (2), and the other end of the partition (26) has a gap with the inner wall of the housing (2). The partition (26) divides the cooling channel (23) into a circulation channel from the liquid inlet (21) to the liquid outlet (22).

6. The power module as described in claim 1, characterized in that, The housing (2) includes a first housing (2a) and a second housing (2b), wherein the first housing (2a) is disposed at the opening of the second housing (2b); a sealing element (24) is disposed between the first housing (2a) and the second housing (2b).

7. The power module as described in any one of claims 1 to 4 and 6, characterized in that, The power device (1) consists of at least two groups, and the at least two groups of power devices (1) share the liquid inlet (21) and the liquid outlet (22). The number of power devices (1) in each group of power devices (1) is at least two.

8. The power module as described in claim 7, characterized in that, The housing (2) includes at least two cooling channels (23) and a connecting hole (27). Each cooling channel (23) is provided with a set of power devices (1). Adjacent cooling channels (23) are connected through the connecting hole (27).

9. The power module as described in any one of claims 1 to 4, 6 and 8, characterized in that, The housing (2) is filled with coolant, which is an insulating liquid.

10. A power conversion device, characterized in that, Includes the power module as described in any one of claims 1 to 9.

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