IGBT (Insulated Gate Bipolar Translator) heat dissipation structure and power equipment

Abstract

The utility model discloses an IGBT heat dissipation structure and power equipment, and the structure comprises a group of IGBT units and a pair of radiators. All the IGBT units in the group are vertically arranged on the PCB side by side; and the two radiators are symmetrically attached to the two sides of the group of IGBT units. The power equipment comprises an IGBT unit, and the IGBT unit adopts the IGBT heat dissipation structure to dissipate heat. Compared with a traditional mode, on the premise that temperature rise is met, the size of the whole heat dissipation system can be reduced, airflow can be efficiently utilized, more heat can be taken away by the airflow, especially under the forced air cooling condition, the airflow of the fan can be efficiently utilized, and the heat dissipation efficiency is improved. And even certain fan cost can be saved.

Description

Technical Field

[0001] This application relates to the field of heat dissipation technology, and in particular to an IGBT heat dissipation structure and power device. Background Technology

[0002] Currently, the main methods for cooling IGBT units on the market are using external heatsinks or a combination of external heatsinks and fans, with external heatsinks being the most common. The reason for external heatsinks is that IGBT units are placed flat on the PCB board, which dictates that the heatsink must also be placed parallel to the PCB board and externally. This method has two drawbacks: firstly, the IGBT unit's leads are relatively long, which is not conducive to heat dissipation; secondly, the need for an external heatsink increases the overall size of the device.

[0003] Another way to place IGBT units is to mount them vertically on the PCB board. This placement allows the heatsink to also be mounted vertically, which solves two drawbacks of horizontally placed IGBT units. It not only reduces pin length but also allows the heatsink to be placed directly inside the device, on the PCB, significantly reducing the overall size of the device. In this case, the heatsink is typically designed as a "dry" type, with the IGBT unit attached to the lower left or right side of the "dry" surface.

[0004] While this type of heatsink can lower the temperature of the IGBT unit, it requires a large heatsink volume. Moreover, the thermal resistance of the heatsink increases continuously from the IGBT unit upwards, which is not conducive to heat dissipation. Only the area directly opposite the IGBT unit is the efficient heat dissipation zone. If a fan is installed in the entire cooling system, then 30% to 50% of the fan's airflow is useless airflow. This airflow is not used efficiently and simply passes over the surface of the IGBT unit, carrying away very little heat. Utility Model Content

[0005] One objective of this application is to provide an IGBT heat dissipation structure that can solve at least one of the defects in the aforementioned background technology.

[0006] Another object of this application is to provide a power device that can solve at least one of the defects in the above-mentioned background art.

[0007] To achieve at least one of the above objectives, the technical solution adopted in this application is as follows: an IGBT heat dissipation structure, comprising a group of IGBT units and a pair of heat sinks; all the IGBT units in the group are mounted side by side on a PCB board; the two heat sinks are symmetrically arranged and correspondingly attached to both sides of the group of IGBT units through a substrate.

[0008] Preferably, each heat sink is bonded to the corresponding IGBT unit via a thermal pad, which is adapted to undergo elastic deformation.

[0009] Preferably, the thermal pad is made of an insulating and thermally conductive material, and the thickness of the thermal pad is 2-3 mm.

[0010] Preferably, the two heat sinks are connected by a first fastener so that a heat dissipation cavity for accommodating the IGBT unit is formed between the two heat sinks with a set gap.

[0011] Preferably, the first fastener includes a bolt and a limiting sleeve, the limiting sleeve being slidably fitted onto the bolt, and the bolt fastening the two heat sinks together so that the heat dissipation cavity is formed between the two heat sinks through the limiting sleeve.

[0012] Preferably, the width of the heat dissipation cavity is less than or equal to the sum of the thickness of the IGBT unit and the thickness of the two thermal pads.

[0013] Preferably, the two heat sinks are connected at the four corners by the first fastener.

[0014] Preferably, one of the heat sinks is fastened to the PCB board by a second fastener, while the other heat sink is not connected to the PCB board.

[0015] A power device includes an IGBT unit and a PCB board, wherein the IGBT unit is mounted vertically on the PCB board and the IGBT unit uses the aforementioned IGBT heat dissipation structure for heat dissipation.

[0016] Preferably, there are multiple IGBT units, and the multiple IGBT units are divided into at least one group, and each group of IGBT units is cooled by the IGBT heat dissipation structure.

[0017] Compared with the prior art, the beneficial effects of this application are as follows:

[0018] Compared to traditional methods, this application can reduce the size of the entire heat dissipation system while meeting the temperature rise requirement. It can also make efficient use of airflow, allowing the airflow to carry away more heat. Especially in forced air cooling, the airflow of the fan can be used efficiently, and even save some fan costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the IGBT heat dissipation structure of this application mounted on a PCB board.

[0020] Figure 2This is an exploded view of the IGBT heat dissipation structure of this application.

[0021] Figure 3 This is a schematic diagram of the structure of the first fastener in this application.

[0022] Figure 4 This is a partial installation diagram of the IGBT heat dissipation structure in this application from a side view.

[0023] In the diagram: PCB board 100, IGBT unit 110, heat sink 210, first fastener 220, bolt 221, limit sleeve 222, thermal pad 230, second fastener 240. Detailed Implementation

[0024] The present application will now be further described in conjunction with specific embodiments. It should be noted that, in the description of this specification, the use of terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0025] In the description of this application, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this application.

[0026] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0027] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0030] One aspect of this application provides an IGBT heat dissipation structure, such as Figure 1 , Figure 2 and Figure 4 As shown, one preferred embodiment includes a group of IGBT units 110 and a pair of heat sinks 210. All the IGBT units 110 are mounted side by side on the PCB board 100; the two heat sinks 210 are symmetrically arranged and correspondingly attached to both sides of the group of IGBT units 110 through a substrate, so that the two heat sinks 210 form a "North" shaped structure to increase the heat absorption efficiency of the IGBT units 110, thereby improving the heat dissipation effect of the IGBT units 110.

[0031] It can be understood that when the traditional IGBT unit 110 is cooled by a single radiator 210, the overall structure of the radiator 210 is in a "dry" shape, and the IGBT unit 110 is only attached to the lower half of one side of the radiator 210, which results in a relatively high overall structural dimension of the radiator 210. In this embodiment, by arranging two radiators 210 on both sides of the IGBT unit 110 in a "north" shape, on the premise of meeting the temperature rise, not only can the height of the radiator 210 be reduced, but also the weight of the device can be reduced. At the same time, through the symmetrical arrangement of the two radiators 210, the heat absorption efficiency of the IGBT unit 110 can be effectively improved. Especially in the case of forced air cooling, the airflow of the fan can be efficiently utilized to allow the airflow of the fan to带走 more heat. Even in some cases, the fan can be downshifted to reduce the cost of the fan.

[0032] It should be known that the number of IGBT units 110 in each group is at least one; since the length of the radiator 210 is generally much larger than the width of a single IGBT unit 110, the number of IGBT units 110 in each group can be set to multiple, and then multiple IGBT units 110 can be cooled by a pair of radiators 210. The specific structure and working principle of the radiator 210 are well-known to those skilled in the art. For the convenience of understanding, the structure of the radiator 210 can be simply described. The radiator 210 mainly includes a substrate and multiple heat dissipation fins; the heat dissipation fins are vertically connected to the substrate at intervals, and the radiator 210 can be adhered to the IGBT unit 110 through the substrate to absorb heat and transfer it to the heat dissipation fins for heat dissipation.

[0033] In this embodiment, as can be seen from the foregoing content, the number of IGBT units 110 in each group is multiple, so there may be installation errors between adjacent or different IGBT units 110. Then, when installing the radiator 210, it may cause some IGBT units 110 to be unable to be adhered to the radiator 210, resulting in poor heat dissipation effect of these IGBT units 110. Therefore, as Figure 2 and Figure 4 shown, in this embodiment, a thermal pad 230 is used to adhere between each radiator 210 and the corresponding side IGBT unit 110, and the thermal pad 230 has a certain elastic deformation ability. Then, when installing the radiator 210, through the extrusion of the radiator 210 on the thermal pad 230, each IGBT unit 110 in this group can be tightly adhered through the elastic deformation of the thermal pad 230, thereby effectively improving the heat dissipation effect of the radiator 210. At the same time, the thermal pad 230 with elastic deformation ability can also play a certain shock absorption role.

[0034] Understandably, based on the function of the thermal pad 230, materials with good thermal conductivity and elastic deformation capability can be selected for the thermal pad 230. Meanwhile, the heat sink 210 is generally made of metal; therefore, to prevent electrical faults between the IGBT unit 110 and the heat sink 210, the thermal pad 230 also needs to be insulating, thus ensuring the safety of the IGBT unit 110 during operation. Various materials can be used for the thermal pad 230 to meet these functions, such as thermally conductive silicone and high thermal conductivity epoxy resin. The thickness of a single thermal pad 230 can be set according to the actual needs of those skilled in the art. A thermal pad 230 that is too thin has a generally poor shock absorption effect, while a thermal pad 230 that is too thick has a slower heat transfer speed; in this embodiment, the thickness of the thermal pad 230 is preferably 2-3 mm.

[0035] In this embodiment, as Figure 2 and Figure 4 As shown, the two heat sinks 210 are connected by a first fastener 220, so that a heat dissipation cavity for accommodating the IGBT unit 110 is formed between the two heat sinks 210 with a set gap. By setting the gap distance of the heat dissipation cavity, it can be ensured that all IGBT units 110 in the group are subjected to uniform force.

[0036] It is understandable that to ensure a stable connection between the two heat sinks 210, multiple first fasteners 220 are often required. These first fasteners 220 need to be arranged at different positions on the heat sinks 210. In this embodiment, it is preferable to arrange the first fasteners 220 at the four corners of the heat sinks 210 for fastening. If bolts 221 are used directly to fix the two heat sinks 210, the tightening stroke of the bolts 221 at different positions can only be controlled by the experience of the operator. This may result in different tightening strokes at different bolt positions, leading to uneven stress on the IGBT units 110 at different positions. Alternatively, if the tightening stroke of the multiple first fasteners 220 is too large, it may cause excessive clamping of the IGBT units 110, resulting in damage. Therefore, in this embodiment, the gap between the heat dissipation cavities formed by the two heat sinks 210 is determined by setting the first fasteners 220. That is, the interval distance between the heat dissipation cavities formed by the two heat sinks 210 after the first fasteners 220 are tightened is equal in each area; and the specific interval distance of the heat dissipation cavities can be set according to actual needs.

[0037] It is important to note that, in order to ensure a tight fit between the heat dissipation cavity and the IGBT unit 110, the width of the heat dissipation cavity needs to be greater than the thickness of the IGBT unit 110, while the width of the heat dissipation cavity needs to be less than or equal to the sum of the thickness of the IGBT unit 110 and the thickness of the two thermal pads 230. This allows the two heat sinks 210 to slightly compress the thermal pads 230 when forming the heat dissipation cavity, thus securing the different IGBT units 110 while ensuring a tight fit between the IGBT units 110 and the heat sinks 210 via the thermal pads 230.

[0038] In this embodiment, the first fastener 220 capable of achieving the above-mentioned functions has various specific structures. For ease of understanding, one of these structures will be described in detail below. For example... Figure 3 and Figure 4 As shown, the first fastener 220 includes a bolt 221 and a limiting sleeve 222. The limiting sleeve 222 is slidably sleeved on the bolt 221. The bolt 221 fastens the two radiators 210 so that a heat dissipation cavity is formed between the two radiators 210 through the limiting sleeve 222.

[0039] In layman's terms, the axial lengths of the limiting sleeves 222 on the first fasteners 220 at the four corners of the heat sink 210 are all the same. Therefore, when the four first fasteners 220 are tightened together, the width of the heat dissipation cavity formed between the two heat sinks 210 is equal to the axial length of the limiting sleeves 222. The axial length of the limiting sleeves 222 can be designed and selected according to the stress conditions of the IGBT unit 110.

[0040] In this embodiment, as Figure 2 and Figure 4 As shown, one heatsink 210 is securely connected to the PCB board 100 via a second fastener 240, while the other heatsink 210 is not connected to the PCB board 100. That is, one heatsink 210 is directly fixed to the PCB board 100, while the other heatsink 210 is placed on the PCB board 100 without being fixedly connected to it. This allows the spacing between the two heatsinks 210 to be adjusted arbitrarily according to actual needs.

[0041] Another aspect of this application provides a power device, such as Figure 1 As shown, one preferred embodiment includes an IGBT unit 110 and a PCB board 100. The IGBT unit 110 uses the aforementioned IGBT heat dissipation structure for heat dissipation. Multiple IGBT units 110 can be provided, and these units can be divided into at least one group according to a set number. Each group of IGBT units 110 can be cooled by the aforementioned IGBT heat dissipation structure. For example... Figure 2As shown, multiple IGBT units 110 are divided into two groups, and both groups of IGBT units 110 use the above-mentioned IGBT heat dissipation structure for heat dissipation.

[0042] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. An IGBT heat dissipation structure, characterized by, The IGBT heat dissipation structure comprises a group of IGBT units and a pair of heat sinks; the group of IGBT units are vertically installed side by side on a PCB board; the two heat sinks are symmetrically arranged and correspondingly attached to the two sides of the group of IGBT units through a base plate.

2. The IGBT heat dissipation structure according to claim 1, wherein Each of the heat sinks is attached to the corresponding side IGBT units through a heat-conducting pad, and the heat-conducting pad is adapted to elastically deform.

3. The IGBT heat dissipation structure according to claim 2, wherein The heat-conducting pad is made of insulating heat-conducting material, and the thickness of the heat-conducting pad is 2-3 mm.

4. The IGBT heat dissipation structure according to claim 2, wherein The two heat sinks are connected through a first fastener to form a heat dissipation cavity with a set gap between the two heat sinks for accommodating the IGBT units.

5. The IGBT heat dissipation structure according to claim 4, wherein The first fastener comprises a bolt and a limiting sleeve, the limiting sleeve is slidably sleeved on the bolt, and the bolt is used to fasten and connect the two heat sinks to form the heat dissipation cavity between the two heat sinks through the limiting sleeve.

6. The IGBT heat dissipation structure according to claim 4, wherein The width of the heat dissipation cavity is less than or equal to the sum of the thickness of the IGBT units and the thickness of the two heat-conducting pads.

7. The IGBT heat dissipation structure according to claim 4, wherein The two heat sinks are connected through the first fastener at the four corner positions.

8. The IGBT heat dissipation structure according to any one of claims 1 to 7, wherein One of the heat sinks is fastened and connected to the PCB board through a second fastener, and the other heat sink is not connected to the PCB board.

9. A power device comprising an IGBT unit and a PCB board, the IGBT unit being mounted upright to the PCB board, characterized in that, The IGBT units are cooled by the IGBT heat dissipation structure according to any one of claims 1-8.

10. The power device of claim 9, wherein, A plurality of IGBT units are provided, and the plurality of IGBT units are divided into at least one group, and each group of IGBT units is cooled by the IGBT heat dissipation structure.

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