阅读说明：本技术 特别是用于航空器的功率组件 (Power module, in particular for an aircraft ) 是由 塞巴斯蒂安·豪德 雅克斯·萨拉特 雷米·珀卡特 于 2019-03-18 设计创作，主要内容包括：本发明涉及一种功率组件(1),其包括：至少两个功率模块,每个功率模块包括安装在底部上的至少一个要冷却的部件,例如电子芯片,冷却元件(4)从该底部延伸；以及中空主体,该中空主体包括用于冷却流体(29)的流动的通道(13),每个功率模块被安装在所述主体上,以使冷却元件(4)通过主体的开口至少部分地延伸到所述通道(13)中,至少一个导流器(21、22、23、24)被安装在两个模块(2)的冷却元件(4)之间的所述通道(13)中,以迫使冷却流体(29)流入到包括冷却元件(4)的通道(13)的区域中。(The invention relates to a power assembly (1) comprising: at least two power modules, each power module comprising at least one component to be cooled, such as an electronic chip, mounted on a base from which a cooling element (4) extends; and a hollow body comprising a channel (13) for the flow of a cooling fluid (29), each power module being mounted on said body such that the cooling element (4) extends at least partially into said channel (13) through an opening of the body, at least one flow director (21, 22, 23, 24) being mounted in said channel (13) between the cooling elements (4) of two modules (2) to force the cooling fluid (29) to flow into the area of the channel (13) comprising the cooling element (4).)

1. Power assembly (1), comprising: at least two power modules (2), each comprising at least one component to be cooled, such as an electronic chip, mounted on a base (3), a cooling element (4) extending from said base (3); and a hollow body (8), the hollow body (8) comprising a flow channel (13) for a cooling fluid (29), each power module (2) being mounted on the body (8) such that the cooling element (4) extends at least partially into the channel (13) through an opening (17) in the body (8), at least one flow director (21, 22, 23, 24) being mounted in the channel (13) between the cooling elements (4) of the two modules (2) so as to force the cooling fluid (29) to flow into the area of the channel (13) with the cooling elements (4).

2. Power assembly (1) according to claim 1, characterized in that the body (8) comprises an upper wall (9), a lower wall (10) and two side walls (11, 12), the upper wall (9), the lower wall (10) and the two side walls (11, 12) defining a channel (13) therebetween.

3. Power assembly (1) according to claim 2, characterized in that the cooling elements (4) are parallel to each other and oriented in the direction (a) of the channel (13).

4. Power assembly (1) according to one of claims 1 to 3, characterized in that the bottom (3) has a lower portion (3b) inserted into the opening (17) of the body (8), the cooling element (4) extending from the lower portion (3b) of the bottom (3).

5. The power assembly (1) according to claim 4, characterized in that the bottom (3) comprises an upper portion (3a), the upper portion (3a) forming a shoulder (6) around the lower portion (3b) of the bottom (3), the upper portion (3a) of the bottom (3) resting on the body (8).

6. Power assembly (1) according to claims 2 and 5, characterized in that the upper wall (9) has a thinned region (16), the thickness of the thinned region (16) substantially corresponding to the thickness of the lower portion (3b) of the bottom (3).

7. Power assembly (1) according to one of claims 1 to 6, characterized in that the flow director (21, 22, 23, 24) extends in the direction (A) of the channel (13) and has a rounded or profiled upstream end (27).

8. The power assembly (1) according to one of claims 1 to 7, characterized in that it comprises: at least one central flow director (21, 22), said at least one central flow director (21, 22) being arranged between the cooling element (4) of the first power module (2) on the one hand and the cooling element (4) of the second power module (2) on the other hand; a first side deflector (23), the first side deflector (23) being located between a cooling element (4) of the first power module (2) and a first side edge (11) of the channel (13); and a second side deflector (24), the second side deflector (24) being located between the cooling element (4) of the second power module (2) and the second side edge (12) of the channel (13).

9. Power assembly (1) according to claim 8, characterized in that the first side deflector (23) and the second side deflector (24) are both in the form of a single structural deflector module (20), the central deflector (21, 22) comprising two adjacent deflector modules (20).

10. Electronic device for use in avionics applications, comprising a power assembly (1) according to one of claims 1 to 9.

Technical Field

The invention relates to a power module, in particular for an aircraft.

Background

The power module comprises an electronic chip, for example made of silicon or silicon carbide (SiC) or gallium nitride (GaN), such as a power transistor, in particular of the MOSFET type, an Insulated Gate Bipolar Transistor (IGBT) or a diode. These chips tend to emit heat that needs to be dissipated because such chips must operate within a defined temperature range. Such power modules may be equipped with aircraft and located in environments that are highly exposed to high heat, making it difficult to evacuate the heat generated by the power modules. Such modules often need to be housed in a closed housing that is isolated from the cooling air flow. Furthermore, the operating mode of such power modules is more and more demanding, as it must be possible to compensate for high power densities to be evacuated over longer periods of time and/or higher heat dissipation peaks spaced apart by shorter rest periods.

Document JP 2016-. The thermal interface ensures good thermal contact between the bottom and the upper wall by compensating for slight flatness deviations due to manufacturing tolerances. The housing defines a channel having an inlet and an outlet for liquid coolant, the coolant circulating in the channel. A cylindrical pin extends from the upper wall of the housing into the channel to form a heat exchange device.

During operation, heat from the power module is transferred to the coolant via the thermal interface, the upper wall, and the cylindrical pin.

However, such cooling has a low efficiency. In fact, the thermal interface forms a thermal insulator, reducing the heat exchange between the bottom of the power module and the upper wall of the casing. The presence of the upper wall also limits the heat exchange and increases the weight of the assembly. Finally, the use of liquid fluids requires the integration of equipment such as pumps and pipes, as well as the integration of sealing devices. In practice, the use of cylindrical pins is hardly compatible with cooling with air.

Disclosure of Invention

The present invention aims to remedy these various constraints in a simple, reliable and inexpensive manner.

To this end, the invention relates to a power assembly comprising: at least two power modules, each power module comprising at least one component to be cooled, such as an electronic chip, mounted on a base from which a cooling element extends; and a hollow body comprising a flow channel for a cooling fluid, each power module being mounted on the body such that the cooling element extends at least partially into the channel through an opening in the body, at least one flow director being mounted in the channel between the cooling elements of the two modules, thereby forcing the cooling fluid to flow into the area of the channel with the cooling elements.

The cooling element and the bottom part form the same part, so that heat can be dissipated directly without having to pass through an insulated thermal interface. In addition, the presence of the flow director ensures that the entire air flow through the channel is used to cool the cooling elements of the module. This improves the cooling performance of the power module. Moreover, the same body allows cooling several modules simultaneously, which allows limiting the weight of the whole assembly.

The air velocity may be adapted to the shape and size of the deflector.

The cooling element may have flat fins or cooling pins, for example cylindrical or conical shapes. Of course any other form is contemplated.

The cooling element may extend over the entire height of the channel.

The body may include an upper wall, a lower wall, and two side walls defining a channel therebetween.

The channels may be straight. The channel may have a first end forming an air inlet and a second end forming an air outlet.

The cooling elements may be parallel to each other and may be oriented in the direction of the channels.

The base may have an upper portion inserted into the opening of the body, and the cooling element extends from a lower portion of the base.

The base may have an upper portion that forms a shoulder around a lower portion of the base, the upper portion of the base resting on the body.

In particular, an upper portion of the bottom may rest on the upper body wall.

The upper part of the bottom part may be fixed to the body, for example by screw engagement.

The upper wall may have a thinned region with a thickness approximately corresponding to the thickness of the lower portion of the base.

The local thinning of the upper wall further reduces the mass of the assembly.

The flow director may extend in the direction of the channel and have a rounded or profiled upstream end.

The term upstream is defined relative to the direction of fluid flow through the channel.

The assembly may include: at least one central deflector arranged between the cooling element of the first power module on the one hand and the cooling element of the second power module on the other hand; a first side deflector located between the cooling element of the first power module and the first side edge of the channel; and a second side deflector located between the cooling element of the second power module and the second side edge of the channel.

The first side deflector and the second side deflector may both be in the form of deflector modules of a single structure, and the central deflector comprises two adjacent deflector modules.

Thus, all deflectors in the assembly can be manufactured using the same deflector module structure. The central deflector then comprises two deflector modules placed side by side symmetrically with respect to the channel axis. Likewise, the two deflector modules forming the side deflector may be placed symmetrically with respect to the channel axis.

In this case, the two ends of the flow guiding module may be rounded or profiled, each end may be upstream with respect to the flow direction of the cooling fluid, depending on the orientation and position of the flow guiding module in the channel.

Each deflector may be screw-coupled to the body. It can also be fixed by other processes (riveting or gluing).

Each flow director may extend over the entire height of the channel.

The deflector also helps to reinforce the main structure, particularly the thinner region of the upper wall.

The electronic component is, for example, a power transistor such as a MOSFET, an IGBT (insulated gate bipolar transistor), or a diode.

The bottom and the cooling element are made of, for example, aluminium or an aluminium alloy. They may also be made of other materials, depending on the specifications of the module.

The coolant is preferably air. Of course, liquid heat transfer fluids or two-phase fluids may also be used.

The assembly is used, for example, to control an electronic actuator or motor.

The invention also relates to an aircraft comprising a power module of the aforementioned type.

The invention furthermore relates to an electronic device for use in avionics applications, comprising a power module of the above-mentioned type.

The invention will be better understood and other details, characteristics and advantages thereof will appear, when the following description is read in connection with the accompanying drawings, given as a non-limiting example.

Drawings

Figure 1 is a front cross-sectional view of a power assembly according to one embodiment of the invention;

Figure 2 is a top cross-sectional view of the power assembly of figure 1;

figure 3 is a perspective view of a deflector module used to form a deflector;

figure 4 is a perspective view of the power module;

figure 5 is a front view of the power module;

figure 6 is a perspective view of the body.

Detailed Description

Fig. 1-6 illustrate a power assembly 1 according to an embodiment of the invention. The power assembly 1 comprises power modules 2, here three power modules 2, each power module 2 comprising a bottom part 3 having a so-called upper part 3a and a so-called lower part 3b, better visible in fig. 5. The terms "upper" and "lower" are defined with respect to the drawings. Of course, the power modules 2 may actually be placed in different orientations.

The fins 4 extend from the lower part of the bottom 3, perpendicular to the plane of the bottom 3. The fins 4 are flat and substantially parallel to each other. The number of fins 4 may vary depending on the width of the module, the target performance, or the maximum target air velocity. The fins add a factor varying between 1 and 50 to the exchange surface. They are distributed over the entire width of the module at a spacing suitable for the requirements. The fins 4 are made of the same material as the base 3, these elements being made of aluminium, for example. The bottom 3 has fixing holes 5 (fig. 4), for example at the corners of the bottom 3.

The upper portion 3a of the bottom 3 forms a shoulder that delimits a peripheral support surface 6 (fig. 5) around the lower portion 3b and the fins 4.

The power module 2 further comprises an electronic chip, not visible in the drawings, mounted on the bottom 3 via an electrically insulating interface. These chips are, for example, power transistors, in particular of the MOSFET type, IGBTs (insulated gate bipolar transistors) or diodes. Furthermore, the connection module 2 has a connection device 7 for connecting the power module 2 to a cable.

Furthermore, the power assembly 1 has a body 8, which is best seen in fig. 6, the body 8 comprising an upper wall 9, a lower wall 10, a first side wall 11 and a second side wall 12. The walls 9, 10, 11, 12 are flat. The lower wall 10 and the upper wall 9 are parallel to each other. The side walls 11, 12 are parallel to each other and perpendicular to the lower wall 10 and the upper wall 9. Said walls 9, 10, 11, 12 define a channel 13 of rectangular cross-section extending along axis a, which channel 13 opens at a first end 14 intended to form an air inlet and at a second end 15 intended to form an air outlet.

The upper wall 9 has a thinned region 16. For example, the thinned region 16 is square or rectangular in shape. The thinned region 16 has a thickness of, for example, 0.5mm to 3 mm. The remainder of the upper wall 9 has a thickness of, for example, 1mm to 5 mm. The thickness of the thinned region 16 corresponds approximately to the thickness of the lower portion 3b of the bottom 3.

The thinned region 16 has at least one opening 17, here three openings 17, which open into the channel 13. Each opening 17 is square or rectangular in shape, complementary to the lower portion 3b of the bottom 3, to avoid large surface discontinuities. Each module 2 is mounted on the body 8 in such a way that the support surface 6 of the upper portion 3b of the bottom 3 rests on the outer surface 18 of the thinned region 16 of the body 8. The lower part of the bottom 3 is housed in the corresponding opening 17 of the thinned region 16 and the fins 4 extend completely into the channels 13 of the body 8. The fins 4 are oriented parallel to the axis a of the channel 13. The fins 4 extend over the entire height of the channels 13. Screws (not shown) are used to fix the bottom 3 to the upper wall 9 of the body 8, said screws being inserted in the holes 5 of the bottom 3 and in the holes 19 of the body 8.

The assembly 1 further comprises a deflector module 20, which deflector module 20 forms so-called central deflectors 21, 22 (see in particular fig. 2) and side deflectors 23, 24, in particular a first central deflector 21 between the fins 4 of the first module 2 and the fins 4 of the second module 2, and a second central deflector 22 between the fins 4 of the second module and the fins 4 of the third module 2. The first side deflector 23 is located between the fins 4 of the first module 2 and the first side wall 11. The second side deflector 24 is located between the fins 4 and the second side wall 12 of the third module 2. The flow deflectors 21, 22, 23, 24 are composed of flow deflector modules 20 of the same structure. Each deflector module 20 extends along an axis a of the body 8, having a first lateral edge 25 intended to come into contact with the air, and a second lateral edge 26. The first side edge 25 should have a rounded, curved or profiled region 27 at each end. In addition, each flow guiding module 20 has a recessed area 28 centrally located at both axial ends 27 of the flow guiding module 20, e.g. opening at the second edge 26.

Each central deflector 21, 22 comprises two deflector modules 20 placed symmetrically side by side with respect to the axis a of the channel 13, so that the second side edges 26 of the two deflector modules 20 are adjacent. The two deflector modules 20 forming the side deflectors 23, 24 are positioned symmetrically with respect to the axis a of the channel 13, so that the second side edges 26 of said deflector modules 20 are in contact with the corresponding side surfaces 11, 12. The deflector module 20 extends over the entire height of the channel 13 so as to completely obstruct the affected area of the channel 13.

The deflector module 20 is fixed to the body 8 by means of screws, which are also used to fix the bottom 3 of the power module 2.

The flow directors 21, 22, 23, 24 help to reinforce the structure of the body 8, particularly the thinner region 16 of the upper wall 9.

During operation, cooling air 29 is introduced through the first or upstream end 14 of the channel 13 and is evenly divided into three portions, each portion passing through a respective fin region 4 of a different power module 2. The flow directors 21, 22, 23, 24 are dimensioned such that the gaps left between the side walls 11, 12 of the body 8 and the regions of adjacent power modules 2 are filled with fins 4 or between the regions of adjacent power modules 2 are filled with fins 4, as best shown in fig. 2. In this way, the deflectors 21, 22, 23, 24 force the air 29 through the different areas of the channel 13 provided with fins 4, facilitating the heat exchange between said fins 4 and the cooling air 29 and, therefore, the cooling of the power module 2. The air 29 then exits the channel 13 through the second or downstream end 15.