WO2017158253A1

WO2017158253A1 - Cooled electronic power module, motor and vehicle comprising such a module

Info

Publication number: WO2017158253A1
Application number: PCT/FR2017/050460
Authority: WO
Inventors: Guy Diemunsch
Original assignee: Institut Vedecom
Priority date: 2016-03-15
Filing date: 2017-03-01
Publication date: 2017-09-21
Also published as: EP3430873A1; FR3049159A1; MA44406A; FR3049159B1

Abstract

The invention relates to an electronic power module for controlling an electric multiphase system, said module comprising a plurality of electronic devices for transforming a so-called incoming electric signal into a plurality of outgoing electric signals arranged so as to feed said electric multiphase system, each electronic device comprising: a so-called lower substrate arranged so as to form an electric circuit, said lower substrate of each electronic device comprising a lower face which is coplanar with a lower face of the susbtrate of at least one other electronic device; at least one electronic component securely connected to the lower substrate and electrically connected to the electric circuit; and a cooling system arranged so as to regulate the temperature of the lower substrate. The invention also relates to an electric vehicle using an electric motor controlled by such a module.

Description

"COOLED POWER ELECTRONIC MODULE, ENGINE AND VEHICLE INCORPORATING SUCH A MODULE"

The present invention claims the priority of the French application 1652196 filed March 15, 2016 whose content (text, drawings and claims) is here incorporated by reference.

Technical area

The present invention relates to a power electronics module, and more particularly to a cooling system of such a module. It is located in the field of power electronics to control multiphase electric motors, including those that equip motor vehicles.

State of the art

Power electronics modules are very widely used in the field of the transport industry. They are subject to many constraints during their operation, including mechanical and thermal. Thus, the temperature gradients introduced at their substrate under the effect of the heat dissipation of the components they support generate thermomechanical stresses cyclically repeated throughout the life of the component, producing thermal fatigue, mechanical stress and consecutively risks of malfunction and / or breakdowns.

For example, poor temperature control degrades the performance of electronic components when it exceeds a planned range of operation and, more sustainably, the temperature variations associated with the periods of operation and shutdown of the modules. Power electronics can also lead to degradations of the electrical connection wires and / or damage or breakage of soldering of the various electronic components, as well as a decrease in their reliability. Thus taking into account the thermal effects related to the operation of power electronics modules is essential to increase the robustness and overall performance of such modules. In parallel with these thermal constraints, it is necessary to reduce the size and bulk of these power electronics modules. However, this reduction is, in the state of the art, limited by the need to cool these modules.

The object of the present invention is to respond at least in large part to the problems described above and to furthermore to other advantages.

Another object of the invention is to solve at least one of these problems by a new power electronics module.

Another object of the invention is to provide a new thermal design for such a module to reduce the adverse effects related to the heat dissipation of the components during operation.

Another object of the present invention is to cool more efficiently such a power module.

Another object of the present invention is to improve the reliability and robustness of such a power module. Another object of the present invention is to reduce breakdowns and maintenance costs of such a power module.

Finally, a general object of the invention is to reduce the size and weight of such a power module while ensuring reliable cooling thereof to facilitate on the one hand the implantation of said module in a vehicle electric or hybrid, and secondly to increase the autonomy of such a vehicle.

Presentation of the invention

According to a first aspect of the invention, at least one of the above-mentioned objectives is achieved with a power electronics module for controlling a multi-phase electrical system, said module comprising a plurality of electronic devices arranged to shape an electrical signal. said entering into a plurality of so-called outgoing electrical signals arranged to power said multiphase electrical system, each electronic device comprising (i) a so-called lower substrate arranged to form an electrical circuit and (ii) at least one electronic component integrally bonded to the lower substrate and electrically connected to the electrical circuit, the lower substrate of each electronic device comprising a lower face which is coplanar with a bottom face of the substrate of at least one other electronic device constituting the power electronics module.

The electronic devices are preferably arranged to control a multiphase electrical system. By way of non-limiting example, each electronic device may be of the type of a power converter, for example an AC-DC converter such as a rectifier or a switched-mode power supply, a DC-AC converter such as an inverter, a DC-DC converter such as a boost ("boost") or buck ("buck") to supply, for example, the low-voltage auxiliaries of the on-board electrical network, the air-conditioning, the audio devices, etc. multiphase electrical systems controlled by at least one module according to the first aspect of the invention or any of its improvements are preferably electric motors used for the propulsion of a motor vehicle or a train.

Preferentially, the lower faces of each electronic device are all coplanar with each other in order to facilitate the electrical connection of the plurality of electronic devices. Alternatively, each electronic device can be made coplanar with at least a portion of the other electronic devices with respect to another reference face of the substrate. Such alignment of the electronic devices is the basic feature of the design of a thermally optimized power electronics module. It allows in particular to distribute the different heat sources in a first heat sink plane. The various improvements of the module according to the first aspect of the invention and which will be described later are intended to improve the heat dissipation on said first heat sink plane.

Advantageously, the substrate of each electronic device contributes to evacuate the heat emitted by the components at its surface during their operation, in particular by conduction phenomena. The substrate is preferably made of a material making it possible both to form an electrical circuit able to interface the electronic components and also to homogenize the temperature emitted locally by said components during their operation.

The substrate may comprise a plurality of stacked materials for example in successive layers and according to a particular topology for performing both an electrical circuit and evacuate the heat dissipated by each component. Preferably, the substrate is of the DBC type for "Direct Bonded Copper" and comprises the plating of at least one copper layer on a ceramic-based support. An electrical circuit can thus be easily made according to the components placed on its surface. The DBC substrate is thus an excellent electrical conductor along the tracks of the electrical circuit designed on its surface, but also excellent electrical insulation on areas around said electrical tracks, and has very good thermal characteristics.

Preferably, a module according to the first aspect of the invention comprises alternately or in a complementary manner at least one of the first improvements below taken optionally in combination:

- The module comprises a so-called upper substrate integrally bonded and / or electrically connected to at least a portion of the electronic components, to define a second heat sink plane. Optionally, the upper substrates of each electronic device are coplanar with at least one other electronic device constituting the power electronics module, and preferably they are all coplanar in order to configure a second identical heat sink plane for all the electronic devices. This so-called double-face configuration makes it possible to promote the evacuation of the calories dissipated by each component towards the first and second heat sink planes, the components being in thermal coupling with each of the lower and upper substrates. This double-sided configuration also protects the components located between the two substrates;

the lower substrate or the upper substrate of each electronic device comprises a first lateral face which is coplanar with a first lateral face of the substrate of at least one other electronic device; the lower substrate or the upper substrate of each electronic device comprises a second side face which is coplanar with a second lateral face of the lower or upper substrate of at least one other electronic device;

each electronic device comprises at least two insulated gate bipolar transistors, each transistor being associated with a diode to form a bidirectional switch. Alternatively, a diode may be associated with a MOFSET (Metal Oxide Grid Field Effect Transistor). Thus each electronic device forms the arm of an inverter, the electronic module may comprise any number of arms. More generally, the components of each electronic device are used in a binary mode, passing or blocking, oscillating at frequencies between 10 kHz and 100 kHz and thus making it possible to carry out pulse width modulations whose frequencies, amplitudes and / or cyclic ratios are controlled;

all the electronic devices comprise the same components; each electronic device extends in a longitudinal direction along which the plurality of components is aligned, thus making it possible both to facilitate the electrical connection with an external electrical circuit and to promote the heat dissipation of the electronic device by distributing more homogeneous sources of heat along said electronic device. Indeed, the online arrangement of the electronic devices of a module according to the invention artfully allows to increase one of the dimensions of said electronic devices;

- Optionally, at least a portion of the electronic devices share the lower and / or higher substrate; Optionally, the first side face of a first electronic device is distinct from the first side face of another electronic device; and the second side face of a first electronic device is distinct from the second side face of another electronic device. In the following paragraphs, a longitudinal axis is defined as being the axis along which the various electronic devices are arranged and preferentially aligned in the module according to the invention. In a comparable manner, a transverse axis perpendicular to the longitudinal axis and normal to the surface of the substrates of the electronic devices of the modules is defined.

According to a second improvement, the module according to the first aspect of the invention or to any one of its first improvements also comprises at least one cooling system comprising:

at least one thermal interface in thermal coupling with at least one of the electronic devices,

a plurality of heat-coupled ducts with the thermal interface, said ducts being arranged to transport a heat-transfer fluid between a first end and a second end.

It is thus possible to evacuate the calories dissipated by the Joules effect at the electronic devices during their operation, to better regulate the temperature of said electronic devices and to avoid overheating that would lead to malfunctions or failures. At least one of the electronic devices is thus integrally bonded to the cooling system via the thermal interface and by any means, such as, for example, gluing, screwing, brazing, crimping or any other means. mechanical assembly. Preferably, the thermal interface is in thermal coupling with substantially the entire surface of a face of at least one of the electronic devices, such as for example with the first or second heat sink plane defined above. Optionally, the thermal interface is thermally coupled with a face of several electronic devices, including electronic devices that are immediately adjacent, such as for example with the first and second heat sink planes.

In general, the thermal interface is arranged to maximize the exchange surface between the electronic devices and said thermal interface.

The thermal coupling between the thermal interface and at least one electronic device can be direct or indirect, for example by means of a thermally conductive material, such as a thermal paste.

Advantageously, the thermal interface may also play the role of a mechanical support with respect to at least two adjacent electronic devices, forming for example a common mechanical reference system on which the two electronic devices are integrally mounted.

Preferably, the thermal interface of such a module according to the second aspect of the invention comprises:

a plurality of first collectors in thermal coupling with at least one face of the lower substrate, called the first regulated face, of at least one of the electronic devices, and / or

a plurality of second collectors in thermal coupling with at least one face of the upper substrate, called the second regulated face, of at least one of the electronic devices.

According to a first alternative, the first regulated face belongs to a first electronic device, while the second regulated face belongs to a second electronic device.

According to a second alternative, the first regulated face and the second regulated face belong to the same electronic device.

This clever configuration takes advantage of the presence of two opposing substrates for at least a portion of the electronic devices, thereby doubling the capacity of the cooling system and improving the cooling of electronic devices. The first regulated face and the second regulated face extend respectively correspond to the first heat sink plane and the second heat sink plane defined above. Thus, each regulated face of the electronic devices is thermally coupled to a plurality of collectors adjacent to each other and preferably covering the entirety of said regulated face. Each collector is integrally bonded and thermally coupled to a conduit so as to promote heat exchange.

Thus, the calories produced at the level of each component are transmitted by conduction and successively to the substrate, then to the thermal interface, and in particular the collectors, and then to the conduits which make it possible to increase the exchange surface with the ambient air which surrounds the electronic module.

In a module according to the first aspect of the invention or to any one of its first and / or second improvements, the conduits carrying the heat transfer fluid comprise alternately or in a complementary manner at least one of the third improvements below taken optionally in combination: _ each duct comprises a section which extends transversely relative to the corresponding electronic devices, preferably perpendicularly;

each duct comprises a coupling section with at least one collector in order to promote thermal coupling between a collector and a duct, each coupling section being delimited on a first side by the first end of said duct; each duct comprises a bent portion located on a second side of the coupling section;

each duct comprises a rectilinear part preferentially in the direct extension of the bent portion, said rectilinear portion being delimited by the second end of said duct. The rectilinear part forms a heat exchange zone with the air for the cooling system;

- The coupling section has at least one complementary half-section to a half-section of at least one collector;

- each conduit is a heat pipe;

at least a portion of the ducts extend laterally beyond the first regulated face in order to improve the robustness and reliability of the cooling system. In other words, the cooling system comprises a first heat exchange zone located on a first side of the electronic devices, and more particularly beyond the first side regulated in the lateral direction; at least a portion of the ducts extend laterally beyond the second regulated face, and preferably in the opposite direction to that of the ducts extending beyond the first regulated face. In other words, the cooling system comprises a second heat exchange zone located on a second side of the electronic devices, and more particularly beyond the second side regulated in the lateral direction; a first thermally coupled conduit with the first regulated face extends laterally beyond said first regulated face and a second conduit thermally coupled with said first regulated face and directly adjacent said first conduit extends laterally beyond the second face; regulated. In other words, a first portion of the heat-coupled ducts with the first regulated face extend towards the first heat exchange zone situated laterally on a first side of the electronic devices, and a second portion of the heat-coupled ducts. with the first regulated face extend towards the second heat exchange zone situated laterally on a second side of the electronic devices. This clever configuration makes it possible to define two thermal exchange zones located laterally on either side of the electronic devices and to increase the exchange surface with the air in order to the cooling system and to improve the cooling of the electronic devices. . This so-called simple alternation configuration also makes it possible to take advantage of the geometry of the module and to distribute the conduits associated with the first regulated face in two different, and preferably opposite, directions. Thus, each electronic device is thermally coupled with a larger number of conduits that pass therethrough laterally to extract the calories produced. The conduits are homogeneously distributed transversely to the entire surface of each electronic device, promoting heat dissipation at the level of the components attached to each electronic device; such a redundancy of the means makes it possible to make the cooling of the power electronics module according to the invention more reliable; a first thermally coupled conduit with the second regulated face extends laterally beyond said second regulated face and a second thermally coupled conduit with said second regulated face and directly adjacent to said first conduit extends laterally beyond the second face; regulated. In other words, a first portion of the heat-coupled ducts with the second regulated face extend towards the second heat exchange zone situated laterally on a first side of the electronic devices, and a second portion of the ducts in coupling. with the second regulated face extend towards the first heat exchange zone situated laterally of a second side of the electronic devices Thus, each face of an electronic device is thermally coupled with a conduit which extends in an opposite direction from the one in which the directly adjacent duct extends. In addition, each face of an electronic device is thermally coupled with a duct which extends laterally in the direction of a heat exchange zone different from that towards which the directly adjacent duct extends. This so-called double-alternation configuration makes it possible cleverly to increase the number of ducts associated with each regulated face and to improve the robustness and reliability of the cooling system.

In a module according to the first aspect of the invention or to any one of its first and / or second and / or third improvements, the cooling system comprises alternately or in a complementary manner at least one of the fourth improvements below taken possibly in combination and each making it possible to further improve the efficiency of the cooling system:

- The cooling system comprises a plurality of fins disposed transversely to the conduits, at least a portion of said conduits being thermally coupled with at least a portion of said fins traversed;

the fins are preferably arranged in the heat exchange zone and along the rectilinear part of said ducts;

- Each fin is arranged on the one hand substantially parallel to the other fins and on the other hand substantially perpendicular to the ducts;

- The cooling system further comprises a housing open on at least two opposite faces, said blowing, and located perpendicularly to the plurality of fins;

in a plane containing a fin, a first portion of the ducts is aligned along a first line and a second portion of the ducts is aligned along a second line, the ducts forming a two-dimensional network in such a plane. By way of nonlimiting example, the ducts associated with the first regulated face may be distributed along a first line, whereas the ducts associated with the second regulated face may be distributed along a second line distant from said first line. This clever configuration makes it possible to increase the density of the ducts used in the cooling system associated with the power electronics module according to the invention while optimizing the pressure drop on the fluid passing through the fins; - The pitch of the duct network in the plane containing a fin is preferably homogeneous;

the conduits aligned along the first line and the conduits aligned along the second line are organized in staggered rows.

Advantageously, a module according to the first aspect of the invention or to any one of its first and / or second and / or third and / or fourth improvements, comprises alternately or in a complementary manner at least one of the fifth improvements. below possibly taken in combination:

- At least one fan located in the extension of a blowing face and arranged to blow air through the plurality of fins and possibly ducts to improve the heat transfer between the air blown by the at least one fan and the fins, and possibly the ducts. Preferably, two fans are arranged laterally on either side of one of the electronic devices, in a plane perpendicular to the longitudinal axis of the module, and advantageously at the level of the heat exchange zones and / or at the level of the parts. rectilinear conduits: the first fan is associated with the ducts that extend laterally from a first side of an electronic device beyond the first regulated face, and the second fan is associated with the ducts that extend laterally from a second side of an electronic device beyond the second regulated face. Thus, when the module according to the first aspect of the invention is configured according to a simple alternation or a double alternation configuration as defined above, each regulated face of a device is cleverly regulated by two independent networks of conduits cooled by two separate fans. Such a heat exchanger is very robust and very reliable because even in the event of failure of one of the fans, each face of a device is always regulated by the remaining fan;

- At least one electrical connection member arranged to electrically supply at least a portion of the electronic devices, said electrical connection member being located in an intermediate position between the thermal interface and said at least a portion of the electronic devices.

Preferably, the electrical connection member comprises:

a plurality of connection tabs in electrical contact with one of the electronic devices, at least one connecting tab extending between two conduits, at least one lug electrically connected to the plurality of connection lugs, said lug being located beyond the ducts and arranged to enable an electrical conductor to be connected thereto.

According to a second aspect of the present invention, there is provided an assembly comprising an electric motor and a power module according to the first aspect of the invention or to any one of its first and / or second and / or third and / or or fourth and / or fifth improvements, said electric motor being controlled by said power module. It will be noted that such an electric motor is configured to propel the vehicle that it equips. According to a third aspect of the present invention, there is provided a motor vehicle comprising an assembly according to the second aspect of the invention.

According to a fourth aspect of the invention, it is proposed to use an assembly according to the second aspect of the invention for propelling a vehicle according to the third aspect of the invention. Various embodiments of the invention are provided, integrating, according to all of their possible combinations, the various optional features set forth herein.

Description of Figures and Embodiments

Other features and advantages of the invention will become apparent from the description which follows, on the one hand, and from several exemplary embodiments given by way of non-limiting indication with reference to the attached schematic drawings on the other hand, on which :

FIG. 1 depicts a diagram resituating the present invention in its context

FIGURE 2 illustrates a perspective view of a power electronics module according to the first aspect of the invention;

FIG. 3 illustrates a detailed view of an electronic device, as implemented in a module according to the first aspect of the invention;

FIGURE 4 illustrates a profile view of a module according to the first aspect of the invention according to its fourth improvement;

FIGURE 5 illustrates a sectional view of the module illustrated in FIGURE 4 and in section plane AA; FIG. 6 illustrates an arrangement of the ducts passing through the fins of a module according to the first aspect of the invention and according to its fifth improvement and;

FIGURE 7 illustrates a detailed perspective view of a module according to the first aspect of the invention and according to its fifth improvement; FIG. 8 illustrates an electrical connection comb through a profile view of a module according to the first aspect of the invention and according to its fifth improvement;

- FIGURES 9 and 10 illustrate in perspective a module according to the first aspect of the invention and implementing a housing and fans according to its fifth improvement.

The embodiments which will be described hereinafter are in no way limiting; it will be possible to imagine variants of the invention comprising only a selection of characteristics described hereinafter isolated from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention compared to the state of the art. This selection comprises at least one feature preferably functional without structural details, or with only a part of the structural details if this part alone is sufficient to confer a technical advantage or to differentiate the invention from the state of the prior art.

In particular, all the improvements and all the embodiments described are combinable with each other if nothing stands in the way of this combination on a technical level.

In the figures, the elements common to several figures retain the same reference.

In the following paragraphs and FIGURES, the Y axis represents the longitudinal axis defined previously and the X axis represents the transverse axis defined above. FIG. 1 illustrates a diagram of a power electronics module 10 according to the first aspect of the invention in its preferred technological context, namely its use for controlling an electric motor 20.

As shown in FIG. 1, the module 10 is located in an intermediate position between a source of electrical energy 30 and the electric motor 20 on the one hand, and between an electrical network 50 and auxiliaries 40 on the other hand. The source of electrical energy 30 provides so-called incoming electrical signals which are shaped by the power electronics module 10 to control the electric motor 20, and in particular its speed of rotation. The source of electrical energy 30 can be of any type, and preferably of the battery type when it is embraqué on a motor vehicle for example. Auxiliaries 40 include all electrical auxiliary elements to the electric motor and vehicle, commonly referred to as low voltage auxiliaries. Low voltage auxiliaries include low voltage battery, engine and passenger cooling systems, driver assistance systems, and comfort and leisure equipment. FIG. 2 illustrates a power electronics module 10 comprising three electronic devices 100 arranged to shape an electrical signal said to come into a plurality of so-called outgoing electrical signals arranged to power a multiphase electrical system, each electronic device comprising (i) a bottom HOa-1 10c substrate arranged to form an electrical circuit and (ii) at least one electronic component integrally bonded to the lower substrate and electrically connected to said electric circuit.

By way of non-limiting example, the incoming electrical signals are preferably of the type of a DC voltage whose nominal value is between 150V and 600V. The outgoing electrical signals shaped by the power electronics module 10 are of the "Pulse Width Modulation" (PWM) type, each electronic device 100 performing such a transformation with a frequency and a frequency. given duty cycle. Preferably, each outgoing electrical signal is out of phase with the others.

Preferably, the components implemented on at least one electronic device 100 are interposed between a lower substrate HOa-1 10c and a top substrate 110e, HOf. The electronic components are electrically connected to at least one of the lower or upper substrates.

Preferably, the lower substrate and / or the upper substrate are arranged to thermally couple with at least a portion of the electronic components and to improve the heat dissipation produced during operation of the module. In the example illustrated in FIG. 2, the module 10 comprises three electronic devices

a first double-sided electronic device 100a and a second double-sided electronic device 100b, each of the two double-sided electronic devices 100a and 100b comprising a lower substrate 110a, 110b and an upper substrate 110e, HOf and

a third single-surface electronic device 100c comprising only a lower substrate 110c. Although adapted to dual-face electronic devices, the invention is however not limited exclusively to this configuration.

The invention aims to cover all combinations of several electronic devices, regardless of their number and the proportion of double-sided electronic devices compared to single-surface electronic devices. Preferably, all the electronic devices are of the same type, and preferentially all of the double-face type.

Advantageously, at least one of the substrates 110 of at least a part of the electronic devices 100 is aligned in one or more directions in order to define a particularly advantageous geometry for the module 10 according to the first aspect of the invention which makes it possible to limit the phenomena of interference between two electronic devices 100 on the one hand, and to facilitate the electrical connection of said module 10 with an external electrical circuit, on the other hand.

According to a first variant, the lower substrate 110 of each electronic device 100 comprises a face which is coplanar with a face of the substrate 110 of at least one other electronic device 100. Preferably, the lower substrates 110 of all the electronic devices 100 are coplanar .

In the example illustrated in FIG. 2, the lower faces of the lower substrate HOa-1 10c of each electronic device 100 are all coplanar.

Such an organization is adapted to a power electronics module requiring the extraction of a large amount of calories, because of the electrical treatment, including its hashing, and the voltage value thus treated. This relative arrangement of electronic devices allows the extraction of calories by its large faces and rationalize the power supply of these devices, aligning them along the same edge.

According to a second variant, optionally complementary to the first variant, the lower substrate 110a-110c or the upper substrate 110e, 10f of each electronic device 100 comprises a first lateral face which is coplanar with a first lateral face of the substrate of at least another electronic device 100, and preferably all other electronic devices 100.

In the example illustrated in FIG. 2, the lateral faces 120 of the lower substrate HOa-1 10c of each electronic device 100 are all coplanar.

According to a third variant, possibly complementary to the first two variants, the lower substrate 110a-110c or the upper substrate 110e, 10f of each device electronics 100 comprises a second lateral face which is coplanar with a second lateral face of the lower or upper substrate of at least one other electronic device 100, and preferably all other electronic devices 100.

In the example illustrated in FIG. 2, the lateral faces opposed to the lateral faces 120 of the lower substrate 110a-1c of each electronic device 100 are all coplanar.

In the embodiment illustrated in FIG. 2, the module 10 thus comprises three electronic devices 100 whose dimensions are identical between each electronic device 100. The electronic devices 100 are all aligned so that the lower and lateral faces of the substrate lower and the upper face of the upper substrates are respectively coplanar.

FIG. 3 illustrates a detailed view of an electronic device 100, as implemented in a module according to the first aspect of the invention.

The module 100 comprises a plurality of electronic components 211-213 fixed integrally to the surface of a substrate 110. The substrate is arranged on the one hand to form an electrical circuit (not shown) providing interconnections between the electronic components 211-213 and their power supply and secondly to participate in the cooling of said electronic components 211-213 during their operation. This problem is accentuated in power electronics which implements high voltages and / or currents: heat dissipations, especially by the Joules effect, are preponderant and it is essential to dissipate the calories produced at the level of each component in order to guarantee their good operation and avoid breakdowns.

The electronic components 211-213 are attached to the surface of the substrate 110 by any known fastening means, and preferably by brazing. They are also electrically connected to the electrical circuit formed on said substrate 110. Advantageously, the means for fixing the electronic components 211-213 on the substrate are electrically conductive.

The components 211-213 are distributed on the surface of the substrate 110 in an advantageous configuration which makes it possible to limit the phenomena of interference between two electronic components 100, to distribute the heat sources more homogeneously along the substrate 110 during operation. of the electronic device 100 and to facilitate the electrical connection of said electronic device 100 with an external electrical circuit.

More particularly, the components 211-213 of the electronic device 100 illustrated in FIG. 3 are substantially distributed in a longitudinal direction Y. The distance between two adjacent 211-213 components is preferentially constant. This advantageous configuration makes it possible to optimize the distribution of the heat sources on the surface of each substrate and thus, ultimately, to improve the heat transfer of the calories produced at each component towards the substrate and the external medium. This configuration also makes it possible to minimize interference phenomena between two adjacent components.

The device 100 is arranged to form, for example, an inverter arm, making it possible to supply at least one voltage and / or at least one alternating current from an incoming signal of different voltage and / or frequency. Such a device 100 comprises at least the three types of components below: at least one insulated gate bipolar transistor 211,

at least one diode 212, at least one diode being associated with at least one insulated gate bipolar transistor in order to form a bidirectional switch oscillating between a passing configuration and a blocking configuration at a frequency typically between 10 kHz and 100 kHz; a feed track 213.

A single-sided electronic device comprises a lower substrate 110, preferably of the DBC type as defined above and on which the components 211-213 are soldered. Preferably, the solders of each component make it possible both to fix them solidly to said substrate, but also to ensure electrical and thermal continuity between the electrical circuit formed on the substrate and said component.

A dual-surface electronic device comprises a lower substrate 110 on which the components 211-213 are soldered, and an upper substrate fixed integrally to the components via their opposite side to fixed on the lower substrate. Preferably, the lower and / or higher substrates are of the DBC type as defined above; and the solders of each component on the lower and / or upper substrates make it possible both to fix them solidly to said substrate, but also to ensure electrical continuity between the electrical circuit formed on the substrate and said component.

With reference to FIGURES 4 and 5, a module according to the first aspect of the invention and comprising a cooling system according to its fourth improvement will now be described.

The module 10 implemented in the illustrated embodiment preferably comprises at least one electronic device 100 of the double-sided type in order to be able to evacuate more effectively the heat dissipated during its operation. Advantageously, all the electronic devices 100 of the module are of the double-face type.

Each electronic device 100 is integrally linked to the cooling system which comprises a thermal interface arranged to ensure a thermal coupling between the electronic devices 100 and conduits 321-324 arranged to transport a coolant between a first end and a second end. The thermal interface is itself in thermal coupling with at least a part of the electronic devices 100.

Optionally, the thermal coupling between the thermal interface and an electronic device 100 is direct or indirect, for example by means of a thermally conductive material such as a thermal paste.

In the example illustrated in FIGURES 4 and 5, the thermal interface is in direct contact with a face of at least one substrate of the electronic devices 100. The thermal interface is integrally bonded to at least one substrate of the electronic devices 100 for example by gluing, screwing or any other mechanical assembly means. In the case where the module comprises an electronic device of the double-sided type, the thermal interface provides thermal contact between the cooling system and firstly a first face of the electronic devices, ie their lower substrate, and other a second side of electronic devices, ie their upper substrate. The upper and lower substrates of the dual-surface devices can be directly thermally coupled via a common or indirect thermal interface through two independent thermal interfaces. In the latter case, fastening means may be provided to sandwich the electronic devices with the thermal interface.

Preferably, the thermal interface extends longitudinally along the Y axis and laterally over the entire surface of the face of the substrate 110 in contact with said thermal interface in order to maximize the heat exchange between the electronic device 100 and the cooling system.

In the illustrated embodiment, the thermal interface takes the form of a plurality of collectors 331, 332 which extend along one side of the substrate 110. The collectors are arranged to be mechanically coupled to the plurality of conduits. 321-324. More particularly, the thermal interface comprises two linear networks of collectors 331, 332, the collectors of each network being preferably regularly spaced.

Each collector 331, 332 is preferably thermally and mechanically coupled with a conduit 321-324. The mechanical coupling can be achieved by any known means, and especially by engagement, preferably without play, for example by brazing, crimping or gluing.

The thermal coupling of each duct with the corresponding collector may be direct or indirect. A thermal glue may optionally be used to improve the thermal coupling between the collector 331, 332 and the corresponding conduit 321-324.

A first network of collectors 331, called first collectors 331, is in thermal coupling with the face of a first substrate 110 opposite to that on which the components are fixed, for example the lower face of the lower substrate of an electronic device 100.

A second network of collectors 332, called second collectors 332, is in thermal coupling with a face of a second substrate 110 opposite to that on which the components are fixed, for example the underside of the upper substrate of an electronic device 100.

In this way, both sides of an electronic device 100 are thermally coupled to the cooling system, thereby improving the ability of the cooling system to dissipate the calories produced at the components of each electronic device 100.

All collectors 331-332 of a collector network are preferably thermally coupled to each other.

In the example illustrated in FIG. 4, the thermal interface therefore comprises two independent collector networks each comprising at least two collectors, each collector network preferably being made in one-piece fashion.

Preferably, the collectors 331, 332 are formed of one or more materials having a high coefficient of thermal conductivity, such as for example copper, magnesium or aluminum. Each network of collectors 331, 332 can be made monolithically or result from the assembly of several separate collectors. Similarly, each collector can be made monolithically or result from the assembly of several parts in order to achieve the thermal and mechanical coupling with the corresponding conduit.

With reference to FIGURE 5, the first and second collectors 331, 332 comprise a concave-shaped through bore formed by a lower end 3311 and lateral edges 3312. The shape of the lower end 3311 is preferably complementary to that of the section of conduits 321 with which the collectors 331, 332 cooperate. In the example illustrated in FIG. 5, the lower end 3311 of the collectors 331, 332 assumes a circular shape, complementary to the circular section of the ducts 321-324.

According to a first variant, the cooling system may comprise a closure piece arranged to hold the duct inside the collector, the closure part being arranged to cooperate with the collector.

According to a second variant, the bore of at least one manifold may take the form of a through hole, for example a circular hole, within which a duct may be inserted and held, for example by means of a free assembly, the conduit 321-324 can be inserted into force in the manifold 331, 332.

The cooling system comprises a plurality of conduits 321-324 arranged to dissipate calories, preferably by circulating a liquid heat transfer fluid and / or gas between a first end 3211-3241 and a second end 3212-3242.

Each duct 321-324 comprises: a first bent portion 3213-3243,

a second rectilinear part 3214-3244 preferably situated in the direct extension of the first bent part 3213-3243, and

a coupling section 3215-3245 arranged to cooperate with a collector 331, 332 in order to perform a mechanical coupling and a thermal coupling with said collector 331, 332. The length of the coupling section is preferably slightly greater than that of the collector 331, 332 so that the first end 3211-3241 of the corresponding conduit is located on the other side of said manifold 331, 332 relative to the bent portion.

In order to improve the efficiency of the cooling system, each duct is in thermal coupling with at least one collector, and preferably exactly one.

Preferably, at least one conduit is a heat pipe.

With reference to FIGURES 4 to 8, the cooling system of a module according to a fourth improvement may comprise a plurality of fins 311-314 arranged transversely to the conduits 321-324 in the X direction, at least a portion of said ducts 321- 324 being in thermal coupling with at least a portion of said traversed fins 311-314. The fins 311-314 preferably take the form of a thin flat plate with regard to its lateral dimensions, typically between a few tenths of millimeters to a few millimeters.

The fins 311-314 are made of at least one material having a high coefficient of thermal conductivity in order to promote the transfer of calories with the surrounding fluid, such as for example aluminum or copper.

Each conduit 321-324 passes through a plurality of fins 311-314. The fins 311-314 thus comprise at least one recess whose dimensions are slightly greater than those of the section of said through ducts 321-324 so as to ensure a thermal coupling between the fins 311-314 and the ducts 321-324 and / or maintaining the fins 311-31 on the conduits 321-324.

Optionally, a fixing means makes it possible to fix a fin 311-314 on each through duct 321-324.

Preferably, the described embodiment uses fins 311-314 which are: mounted along at least one segment of the rectilinear portion 3214-3244 of the ducts

321-324, and / or

- regularly spaced between them, and / or

- arranged substantially parallel to each other, and / or

- arranged substantially perpendicular to the ducts 321-324. In a plane containing the fins, said ducts 321-324 are preferably organized in a two-dimensional array, and preferably in two rows spaced from one another, a first portion of the ducts 321-324 being aligned along a first line and a second part of the ducts 321-324 being aligned along a second line.

In FIGURE 6, the ducts 321 are aligned along the first so-called upper line and located above the second so-called lower line in which the ducts 322 are aligned.

According to a first variant, the fins 311-314 associated with the conduits 321-324 aligned along the first upper line are distinct from the fins 311-314 associated with the conduits 321-324 aligned along the second lower line. According to a second variant, the conduits 321-324 aligned along the first upper line and the conduits 321-324 aligned along the second lower line are thermally and / or mechanically coupled with the same group of fins 311-314, each fin being crossed. simultaneously by a conduit 321-324 associated with the upper line and another conduit 321-324 associated with the lower line.

Several configurations are possible regarding the lateral distribution of the 321-324 ducts. The different configurations covered by the present invention make use of all the combinations making it possible to distribute the conduits 321-324 laterally beyond the first and second regulated faces of the electronic devices and according to the first and / or second line as defined above.

According to a first configuration, the conduits 321-324 can be mounted on the collectors 331-332 and alternately oriented laterally beyond the first regulated face and beyond the second regulated face. The conduits 321-324 of the same network of collectors 331-332 may all be aligned along the first line or be distributed along the first and second lines.

According to a second configuration, the conduits 321-324 of the same network of collectors 331-332 are all oriented on the same side with respect to the first or the second regulated face. The conduits 321-324 of the same network of collectors 331-332 may all be aligned along the first line or be distributed along the first and second lines. In the embodiment illustrated in FIG. 4, a first portion of the ducts 321 associated with the first collectors 331 is oriented laterally on a first side of the electronic device 100 and a second portion of the ducts 324 associated with the first collectors 331 is laterally oriented. a second side of the electronic device 100 opposite to the first side. Similarly, a first portion of the ducts 324 associated with the second collectors 332 is oriented laterally of a first side of the electronic device 100 and a second portion of the ducts 324 associated with the second collectors 332 is oriented laterally of a second side of the electronic device 100 opposite to the first side. Optionally, this alternation in the direction of extension of the ducts is made between two ducts immediately adjacent to one another. The invention also covers the case where a first pair of ducts is alternated with a second pair of ducts.

This advantageous configuration makes it possible cleverly to project the heat exchange surfaces in different zones and spaced from each other with respect to the electronic devices 100. Thus, for a given cooling face of an electronic module 100, the dissipation thermal protection is provided jointly by a first part of the cooling located on a first side of said device and by a second portion of a second side opposite said first side.

Advantageously, as visible in FIGS. 6 and 8, the ducts 321 aligned along the first line and the ducts 322 aligned along the second line are staggered in a plane formed by a fin. The conduits 321 aligned along the first line are all aligned with a constant spacing pitch. Likewise, the conduits aligned along the second line 322 are all aligned with a constant spacing pitch. Preferably, the spacing pitch of the ducts aligned along the second line 322 is identical to the spacing pitch of the conduits aligned along the first line 321. The staggered organization of the ducts 321-324 is achieved by means of a shifting of the ducts 321. of the first line with respect to the conduits 322 of the second line. The offset is advantageously equal to half the spacing pitch of the conduits 321-234.

This clever configuration makes it possible to promote the flow of air between each duct 321-324 and to prevent, in a direction perpendicular to the alignment direction of ducts 321-324, the heat exchange between each duct 321-324. and the air is maximum. More particularly, the staggered configuration of the ducts 321-324 makes it possible to limit the interferences between the ducts 321-324, in particular by the shading effect that a duct overlay involves.

Preferably, the ducts pass through the fins so that, in the plane of said fins, the surface of the fin located above said ducts is equal to that below.

According to FIGURES 4, 7 and 8, and according to a fifth improvement of the first aspect of the invention, the module 10 also comprises an electrical connection member 520 arranged to electrically supply at least a portion of the electronic devices 10, said connection member electrical 520 extending into at least a portion of the electronic devices. The connection member 520 preferably comprises (i) a plurality of connection tabs 521 in electrical contact with at least one of the electronic devices, each connecting tab 521 extending laterally between two adjacent conduits 321-324, and (ii) at least one lug 511-516 electrically connected to at least a portion of connecting lugs 521 via a longitudinal section 523. The electrical connection member 520 is arranged to establish at least one electrical connection with at least one electronic devices 10 at at least one feed track 213. In FIGURES 4, 7 and 8, the connection member 520 shown takes the form of a connecting comb 520.

The module 10 comprises two groups of electrical connection combs 520 each located on either side of the electronic devices 100. Each group comprises a number of comb preferably equal to the number of electronic devices 100 of the module 10. In the illustrated example, two groups of three combs 520 are arranged on either side of the electronic devices.

Each comb 520 comprises a lug 511-516 arranged to be able to connect an electrical conductor, for example by brazing or screwing. In the illustrated example, each lug takes the form of a flat dough having a central opening in order to introduce an electrical conductor to establish an electrical connection.

Lugs 511-516 are advantageously located laterally beyond the ducts and fins in order to easily connect an electrical conductor.

Each comb 520 and each lug 511-516 are at least partially conductive. They are for example formed at least in part of a metallic material such as copper.

Thus, each comb 520 is arranged to establish an electrical connection between the corresponding lug 511-516 and one of the electronic devices 100, each comb being preferably connected to a different electronic device 100, for example by soldering on a pad 213c or 213d illustrated in FIG. 3. A first portion of the lugs 511-516 is preferably arranged to conduct an incoming electrical current carried by an electrical conductor to at least one of the electronic devices 100. A second portion of the lugs 511-516 is preferably arranged to drive an outgoing electric current shaped by at least one of the electronic devices 100 to an electrical conductor. Each comb 520 is electrically insulated from the other combs 520.

Optionally, each comb 520 can be made monolithically, or part of them can be made monolithically, including those located on the same side of the electronic devices 100.

FIGURES 9 and 10 illustrate a perspective view of a module 10 according to the first aspect of the invention and implementing a housing and / or fans according to its fifth development. In FIGURE 9 identical to FIGURE 10, one half of the housing has not been shown for ease of understanding.

In addition to the other elements already described above, taken in combination or in an isolated manner, such a module 10 thus comprises: a housing 700 open on at least two opposite faces, called AF blowing faces, located perpendicular to the plurality of fins, and / or

- At least one fan 711-713 located in the extension of a blowing face and arranged to blow air through the plurality of fins 311-314 and 321-324 ducts. The module 10 described in FIGS. 9 and 10 comprises three electronic devices longitudinally aligned in the Y direction and in the configuration illustrated in FIG. 2.

The housing 700 comprises a plurality of plates 701-705 arranged to form a housing around the at least one electronic device 100 and / or the cooling system. The plates may be bonded together or fixed directly to the module 10. The housing optionally comprises fastening means cooperating with complementary means on the module 10, so that the housing is held in position once fixed on said module 100.

The second ends of each conduit 321-324 are preferably located outside the housing 700. For this purpose, the lateral face 704 comprises openings whose dimensions are slightly greater than those of the conduit 321-324 and / or its second end 3212-3234.

The housing comprises a first open face 730 and / or a second open face 740, that is to say unobstructed by a plate, so that an air flow is possible between the fins 311-314 , the air rushing between said fins 311-314 by the first open face 730 and, optionally, emerging through the second open face 740. In a more general manner, the housing is arranged to form between the blowing faces a air channel passing through the cooling system at the plurality of conduits 321-324 and the plurality of fins 311-314.

The circulation of air inside the cooling system can be natural or forced, thanks in particular to at least one fan 711-713. Preferably, the module 10 according to the first aspect of the invention thus comprises two air channels passing through the cooling system:

a first air channel is formed of a first side of the at least one electronic device 100, beyond the first regulated face and at the level of the rectilinear part 3214, 3224 of the plurality of ducts 321, 322 and the plurality of fins 311, 312. The first air channel is visible in FIGURE 9 between the arrows 730 and 740 on the visible side of the housing 700; and

a second channel is formed of a second side of the at least one electronic device 100, beyond the second regulated face and at the level of the rectilinear part 3234, 3244 of the plurality of conduits 323, 324 and the plurality of fins 313, 314. The second air channel is embodied by the two groups of fins exposed in FIG. 9.

The first and second air channels are advantageously oriented perpendicularly to the fins 311-314, and preferably in the longitudinal direction of the module 10. More particularly, the blowing faces are arranged in such a way that a flow of air It flows in a laminar manner and can reach each duct without detours.

Advantageously, the dimensions of the rectilinear portions 3214-3244 of the ducts 321-324 correspond to the lateral dimensions of a fan 711-716.

The preferred embodiment of the invention will now be described. In the preferred embodiment, the module 10 according to the first aspect of the invention comprises:

three electronic devices 100, each electronic device 100 comprising a lower substrate and an upper substrate, the three devices being aligned in a longitudinal direction Y and the opposite faces of each lower and respectively upper substrate being respectively coplanar with each other;

a cooling system according to the improvements of the invention and comprising:

first collectors 331 in thermal coupling with the entire surface of the first regulated face of each electronic device 100; second collectors 332 in thermal coupling with the entire surface of the first regulated face of each electronic device 100; a plurality of heat pipes 321-324, each manifold 331, 332 being thermally coupled with a heat pipe 321-324;

a plurality of fins 311-314 disposed along the straight portion 3214-3244 of each heat pipe 321-324 perpendicular to said heat pipes 321-324; _ six fans 711-716 arranged perpendicularly to the rectilinear parts 3214-

3244 heat pipes 321-324;

a housing 700.

In the preferred embodiment, a first portion of the heat pipes 321, 322 associated with the first collectors 331 extends laterally beyond the first regulated face and a second portion of the heat pipes 321, 322 associated with the first collectors 331 extends laterally. beyond the first regulated face. In addition, each heat pipe 321, 322 associated with the first collectors 331 extends in a direction different from that in which extends the heat pipe 321, 322 directly adjacent.

In a comparable manner, a first portion of the heat pipes 323, 324 associated with the second collectors 332 extends laterally beyond the first regulated face and a second portion of the heat pipes 323, 324 associated with the second collectors 332 extends laterally beyond of the first regulated face. In addition, each heat pipe 323, 324 associated with the second collectors 332 extends in a direction different from that in which extends the heat pipe 323, 324 directly adjacent. Each first and second portion of the heat pipes 321-324 associated respectively with the first and second collectors is in thermal coupling with a separate portion of the fins 311-314. In other words, the fins 311-314 are arranged in four distinct groups, each fin group 311-314 being in thermal coupling with one and only one of the first and second portions of heat pipes 321-324 defined above. The fans 711-716 are distributed around the electronic devices 100 so as to blow air at the straight portions 3214-3244 of the heat pipes 321-324, each regulated face of each electronic device 100 being thus thermally regulated via two separate fans 711-716 and remote from each other, associated with a set of heat pipes 321-324 and fins 311-314 separate and distant. This preferred embodiment thus provides a power electronics module whose clever design optimizes the management of thermal aspects. The use of an active cooling system associating heat pipes with fins and fans in a new and advantageous configuration makes it possible to improve the reliability and the robustness of said system. module. Indeed, for each of the regulated faces of the electronic devices, the redundancy and the spatial distribution of the elements that make up said heat exchanger makes it possible to ensure cooling even when a fan fails.

Of course, the invention is not limited to the examples that have just been described and many adjustments can be made to these examples without departing from the scope of the invention. In particular, the various features, shapes, variants and embodiments of the invention can be associated with each other in various combinations to the extent that they are not incompatible or exclusive of each other. In particular all the variants and embodiments described above are combinable with each other.

Claims

claims

Power electronics module for controlling a multiphase electrical system, said module comprising a plurality of electronic devices arranged to shape an electrical signal said to be in a plurality of so-called outgoing electrical signals arranged to power said multiphase electrical system, each electronic device comprising:

a so-called lower substrate arranged to form an electrical circuit,

at least one electronic component integrally bonded to the lower substrate and electrically connected to the electric circuit,

characterized in that the lower substrate of each electronic device comprises a bottom face which is coplanar with a bottom face of the substrate of at least one other electronic device constituting the power electronics module.

Module according to the preceding claim, characterized in that it furthermore comprises at least one cooling system comprising:

Module according to the preceding claim, characterized in that the thermal interface comprises:

Module according to any one of claims 2 or 3, characterized in that the plurality of conduits comprises a section which extends transversely and / or perpendicular to the corresponding electronic devices.

5. Module according to any one of claims 2 to 4, characterized in that each duct comprises a first bent portion and a second straight portion.

Module according to any one of claims 3 to 5, characterized in that at least a portion of the ducts extend laterally beyond the first regulated face and / or beyond the second regulated face.

Module according to any one of claims 3 to 6, characterized in that a first thermally coupled duct with the first regulated face extends laterally beyond said first regulated face and a second duct thermally coupled with said first regulated face and adjacent to said first conduit extends laterally beyond the second regulated face.

Module according to any one of claims 3 to 7, characterized in that a first conduit thermally coupled with the second regulated face extends laterally beyond said second regulated face and a second conduit thermally coupled with said second regulated face and adjacent to said first conduit extends laterally beyond the second regulated face.

9. Module according to any one of claims 3 to 8, characterized in that the cooling system comprises a plurality of fins disposed transversely to the ducts, at least a portion of said ducts being in thermal coupling with at least a portion of said fins. crossings.

10. Module according to the preceding claim, characterized in that each fin is arranged on the one hand substantially parallel to the other fins and on the other hand substantially perpendicular to the ducts.

11. Module according to any one of claims 9 or 10, characterized in that the cooling system further comprises a housing open on at least two opposite faces, said blowing, and located perpendicularly to the plurality of fins.

12. Module according to any one of claims 9 to 11, characterized in that it comprises at least one fan located in the extension of a blowing face and arranged to blow air through the plurality of fins.

13. Module according to any one of claims 9 to 12, characterized in that, in a plane containing a fin, a first portion of the ducts is aligned along a first line and a second portion of the ducts is aligned along a second line.

14. Module according to any one of claims 9 to 13, characterized in that it comprises an electrical connection member arranged to supply electrically at least a portion of the electronic devices, said electrical connection member being located in an intermediate position between the thermal interface and said at least a part of the electronic devices.

15. Module according to the preceding claim, characterized in that the electrical connection member comprises:

a plurality of connection tabs in electrical contact with one of the electronic devices, each connection tab extending between two ducts,

at least one lug electrically connected to the plurality of connection lugs, said lug being located beyond the ducts and arranged to enable an electrical conductor to be connected thereto.

16. Motor vehicle comprising an assembly comprising an electric motor and a power module according to any one of the preceding claims, characterized in that the electric motor is controlled by the power module according to any one of the preceding claims.