Power module with power electronic devices on a substrate and power electronic circuit with such a power module

Abstract

The invention relates to a power module (11) having a first power electronic device (31) and a second power electronic device (32). The invention also relates to a power electronic circuit in which the power module is used. According to the invention, the electronic devices (31, 32) can be pre-mounted on a substrate (12, 13), thereby forming a chip-ceramic composite. The corresponding chip-ceramic composites can be stacked in a simple manner for the production of the power module, whereby a modular structure and an advantageously space-saving arrangement are possible. In addition, a large proportion of identical components makes the design of the modularly constructed power electronic circuit inexpensive.

Description

[0001] The present invention relates to a power module having a first power electronic device mounted on a first substrate. In addition, the present invention also relates to a power electronic circuit having a plurality of power modules.

[0002] Power electronics are usually adapted to the associated given application. These applications vary, resulting in considerable costs in designing the power electronics and in their production. Individualized applications are particularly impeding the automatability of manufacturing power modules.

[0003] The object of the present invention is to provide a power module or a power electronic circuit, wherein the power electronic circuit can be produced with low outlay in terms of design or production, in particular in the case of individual production of the power module or in small quantities.

[0004] According to the present invention, the solution to the technical problem described is achieved by using the above-mentioned power module in the following manner, that is, a second power electronic device mounted on a second substrate is provided, wherein the first substrate, the first device, the second substrate and the second device form a stack and / or a planar arrangement (of the stack if necessary). It is thus advantageously possible to achieve a very space-saving arrangement of the power electronic device. In addition, the power electronic device and the associated substrate can each form a pre-installable power electronic structural unit (hereinafter referred to as a "basic unit" and therefore a power module in the smallest form), so that the power module can be easily matched to different applications by stacking and / or docking the basic unit. A composite of multiple basic units, i.e., a stack, for example, can also be pre-installed to construct a power electronic circuit with different numbers of stacked and / or docked modules. Without greater costs, the specification design of the power module for different application situations is advantageously achieved by using a high proportion of identical components.

[0005] According to an advantageous design of the invention, the upper side of the second component is electrically connected to the lower side of the first substrate. The terms "upper side" and "lower side" are not related to the installation position or positioning of the power module during operation. On the contrary, the component is a surface-mounted component, wherein the component is usually mounted on the upper side of the substrate, i.e., the lower side of the component is mounted on the upper side of the substrate. Therefore, a reference point is generated by the surface mounting regardless of the installation position of the power module, and the reference point is also used to define the "upper side" and "lower side" later.

[0006] The electrical connection of the upper side of the second component to the lower side of the first substrate has the advantage that the component used can be electrically connected not only to the first substrate via its lower side but also to the second substrate via its upper side. In other words, a component can be used which has electrical contact surfaces on its upper side and its lower side. In this way, in particular power electronic components with advantageously large contact surfaces can be contacted, which allows the routing of greater currents and, moreover, improves the thermal dissipation of lost heat.

[0007] According to another design of the present invention, the second component is in contact with the first component via an electrical connection path. By providing such an electrical connection path, it is advantageously possible to connect the first component and the second component to each other. This enables additional applications when designing a circuit implemented by a power module, because it is possible to electrically connect the components in a direct manner.

[0008] Advantageously, the electrical connection path between the first component and the second component can be configured as a metallized through-hole, in particular as a via. This advantageously enables particularly direct contact, wherein the components on either side of the first circuit carrier are mounted on the upper side and the lower side of the substrate. The metallized through-holes lead to an electrical connection between the components over the shortest path. As a result, higher currents can flow between the components with less losses, thereby making it possible to construct an efficiently operating power electronic circuit.

[0009] According to a special design of the present invention, the electrical connection path is implemented as a half-bridge, which provides phase contacts. As a result, for example (when using a plurality of other power modules at the same time) a power electronic circuit can be realized in which a direct current is converted into a single-phase or multi-phase alternating current. The phase contacts provide a connection possibility so that an alternating current can be output by the power module or an electronic circuit realized with the power module. As a result, it is possible to produce a power electronic circuit with a high power density per unit volume.

[0010] According to another embodiment of the invention, at least one spacer is arranged between the first substrate and the second substrate, which spacer connects the first substrate and the second substrate to each other. This makes it possible to additionally mechanically stabilize the power module. In addition, the spacer can also be used as a distance keeper in order to achieve a defined electrical contact of the electronic component.

[0011] According to an advantageous embodiment of the invention, the spacer has a conductive path and is implemented such that the spacer

[0012] - is mechanically stable and electrically conductive, and / or

[0013] - covering and / or representing signal and / or power paths,

[0014] and / or

[0015] - Provide some or all potentials on all planes.

[0016] Advantageously, the spacer can also be arranged with the same technical effect or partially with the same technical effect between the first substrate and the first base plate, wherein the first component is also connected to the first base plate on the top side. The first base plate can advantageously additionally serve as a circuit carrier.

[0017] Furthermore, according to the expansion scheme of the spacer, it can be provided that the spacer is designed to be conductive. It is therefore advantageously possible that at least one spacer connects the conductor tracks on the first substrate and the first bottom plate to each other in an electrically conductive manner. The first substrate and the second substrate can also be electrically conductively connected to the spacer, wherein the conductor tracks on the substrates can also be connected to each other. The conductive spacer thus enables more complex connections between components, thereby advantageously increasing the design freedom for realizing power electronic circuits. The power module according to the invention can thus be designed for the smallest space and can perform different electrical technical problems.

[0018] A special embodiment of the invention provides that the first base plate and / or the second base plate has a cooling structure. This makes it possible to reliably and quickly dissipate the heat accumulated in the power electronic circuit during operation. Due to the high compactness of the power module, it is advantageous if the cooling structure is directly connected to the base plate, thereby forming a short transfer path for the heat to be dissipated. The cooling structure can be formed, for example, by a rib cooler which is connected to the corresponding base plate or forms a common component with the base plate (integral production).

[0019] The creation of a power module according to the invention has the advantage that it can be combined with power modules of the same design to form a power electronic circuit whose functionality can be adapted to different applications with little effort. In particular, by connecting a plurality of power modules in parallel, it can be achieved that the power electronic circuit generated by the power modules can be adapted to different required power ranges.

[0020] Accordingly, the above-mentioned technical problem is also solved by a power electronic circuit, in which the described power module is used, wherein a plurality of power modules are electrically connected by merging. The power electronic circuit thus produced can be produced with a plurality of identical components based on a modular structure, which advantageously minimizes the manufacturing costs. In addition, the following advantage is produced, namely the disassembly of the power electronic circuit can be carried out in a simple manner. Thus, for example, a defective power module can be replaced at little cost.

[0021] The design scheme of the power electronic circuit mentioned above stipulates that the power module has two power electronic devices configured as a first switching element and a second switching element. In other words, one electronic device is configured as a first switching element, and the second electronic device is configured as a second switching element. The first switching element and the second switching element are combined into a common power connection, which can be configured as a phase contact for the phase of a three-phase current in particular. This common power connection is also called a half bridge. In addition, the first switching element has a first power connection implemented as a positive pole, and the second switching element has a second power connection implemented as a negative pole. It is therefore possible to alternately switch the power connection to a negative pole and a positive pole by means of a switching element, thereby generating an alternating current. Therefore, the power electronic circuit can advantageously be operated as a modularly constructed frequency converter.

[0022] According to the design of the power electronic circuit, it can be provided that the power modules are divided into three groups each having the same number of power modules, wherein in each of the three groups, the common power connections are electrically connected to each other, and three common power connections each having a common phase contact are constructed. Therefore, a three-phase current can be advantageously generated using this circuit, wherein interconnecting the power modules into groups also allows switching of larger currents. Here, a plurality of power modules are connected in parallel, so that the required current can be switched. In order to also supply the power modules with a DC voltage, the first power connections of all switching elements must be electrically connected to each other and form a common negative pole, while the second power connections of all switching elements are also electrically connected to each other to form a common positive pole.

[0023] Furthermore, it can be advantageously provided that the power modules are connected in series. For this purpose, the basic units are connected in a suitable manner, see Figure 1 , whereby a series circuit can be created and thus branches of an inverter can be created. Several units are designed here so that a series circuit can be realized in a simple manner by stacking, thereby opening up a large number of variation possibilities.

[0024] According to an advantageous embodiment of the invention, there may be a combination of parallel circuits and series circuits. This is the case, for example, if two or more basic units are stacked and these stacks are then connected in a butted manner. A series circuit is then realized by the corresponding stacks, for example, and a parallel circuit is realized by butting the series-connected stacks of basic units.

[0025] Advantageously, provision can also be made for the electrical connection of the common power connection to be formed by the first electrical connection and the second electrical connection, respectively. This arrangement can be easily assembled by arranging the power modules one after the other in series, whereby the electrical connection is automatically formed.

[0026] The power electronic device is preferably implemented as a bare chip. The bare chip can be in direct contact with the substrate, for example, by means of a sintered connection, which also ensures electrical contact. The substrate can preferably be made of ceramic. Ceramics do not conduct current, thereby ensuring electrical insulation at the same time. Therefore, the electronic circuit can be realized by structuring the conductive coating on the substrate. Thus, for example, a contact surface for contacting the power electronic device is provided.

[0027] The invention will be described in further detail below with reference to the drawings. Identical or mutually corresponding elements of the drawings are each provided with the same reference numerals and are only described repeatedly in the case of differences between the individual drawings.

[0028] The embodiments described below are preferred embodiments of the present invention. In the embodiments, the components described in the embodiments are several individual features of the present invention that can be considered independent of each other, which also improve the present invention independently of each other, and therefore can also be considered as components of the present invention individually or in a combination different from that shown. In addition, the described embodiments can also be supplemented by other already described features of the present invention.

[0029] in:

[0030] Figure 1 An embodiment of a power module according to the invention is shown as a side view;

[0031] Figure 2 As a simplified block diagram, a plurality of Figure 1 or a power electronic circuit of a similarly constructed power module;

[0032] Figure 3 Schematic diagram for contacting according to Figure 2 The power electronic circuit is based on Figure 1 Circuit diagram of the power module;

[0033] Figure 4 shows a top view of a stack consisting of two basic units; and

[0034] Figure 5 Shown along Figure 4 Cross-sectional view along line AA.

[0035] Figure 1 A power module 11 is shown (the system boundary is indicated by a dashed line), which also shows how a plurality of power modules can be combined to form a power electronic circuit. The power module 11 is formed by a first component 31 and a second component 32, which are each implemented as a first transistor 44 and a second transistor 45. The first transistor 44 and the second transistor 45 (especially when connected in series as in this case) form a circuit with a half bridge 64, wherein in Figure 1 The circuit is shown in Figure 3 The circuit will be described in detail later.

[0036] The first component 31 and the second component 32 are mounted on the first substrate 12 and the second substrate 13, respectively. Different conductor paths are used on the first substrate 12 and the second substrate 13. In addition, the second substrate 13 is mounted on the second base plate 19, wherein electrical contact can also be made here, such as in Figure 1 The first component 31 is also electrically contacted via the first base plate 18 .

[0037] In order to realize the circuit, spacers 17, 17a are also provided, which enable electrical contact between the individual boards, namely the first base plate 12, the second base plate 13, the first bottom plate 18 and the second bottom plate 19. As a result, the conductor lines arranged on the boards can be electrically contacted with each other. The electrical contact is realized by the solder connection 23. Figure 1 By way of example, only some of the welded connections are provided with reference numerals.

[0038] according to Figure 1 Different conductor lines form a positive pole 46, a negative pole 47 and a phase contact 48. A DC voltage can exist on the positive pole 46 and the negative pole 47. An AC voltage can be tapped through the phase contact 48. Therefore, according to Figure 1 The power module 11 can be used as a converter. Figure 3 The function of the converter is also explained in detail.

[0039] A half bridge 64 is provided in the first substrate 12 as a metallized through hole. This has the advantage that the first component 31 and the second component 32 can be contacted with each other in a very direct manner, thereby achieving a short electrical path. The phase contact can then be cut off via the conductor line on the first substrate 12.

[0040] Furthermore, cooling structures 21, 22 designed as fin coolers are implemented on the first base plate 18 and the second base plate 19. In this way, the heat generated in the first electronic component 31 and the second electronic component 32 can be dissipated through the two base plates 12, 13 and the base plates 18, 19, respectively. In this case, short paths enable effective cooling.

[0041] In addition, Figure 1It can be clearly seen that the smallest, pre-manufacturable unit (basic unit) for modular production of power modules is respectively a composite of substrates 12, 13 and components 31, 32 and possibly also spacers 17, 17a. Such basic units, which are exemplarily implemented here as chip ceramic composites (CKVs for short), can be produced in large quantities. In the stacking of basic units, series circuits and / or parallel circuits are realized. The substrate can be composed of ceramic, for example, and the substrate is equipped with a plurality of components. The individualization of the corresponding CKV can then be realized, for example, by separating the substrates.

[0042] The structural design provides the possibility of sealing off the relevant structural space after installation (see Figure 1 , whereby a circumferential seal can be provided). The seal spans the gap between the base plates 18, 19, thereby forming a structural space (not shown). This can produce advantages for insulation strategies (especially vacuum and gas) and for use under critical environmental conditions (in moisture, toxic gases, etc.). The structural design also provides the possibility of integrating sensors (not shown) for example temperature and current.

[0043] Figure 2 shows how to combine multiple Figure 1 The power modules 11 are combined into a power electronic circuit 42. Five power modules 11 are respectively arranged in a column 43, wherein a total of six columns are provided. Figure 1 As can be seen in FIG. 1 , a contact possibility is created for both, namely the first component 31 and the second component 32, in Figure 2 A contact possibility is realized for each power module 11 in Figure 3 It is schematically shown as a circuit diagram in FIG.

[0044] Figure 3 A capacitor 15 is shown for completing the circuit. This is used to simplify the illustration, wherein alternatively, a plurality of capacitors connected in parallel can also be used. Figure 3 The same applies to the first substrate 12 and the second substrate 13 and the power electronics mounted thereon, which are constructed by means of a first transistor 44 and a second transistor 45. The first transistor 44 is connected with its source to a positive pole 46, also referred to as the high voltage side, and the second transistor 45 is connected with its drain to a negative pole 47, also referred to as the low voltage side. The drain of the first transistor 44 and the source of the second transistor 45 are connected to one another, whereby a half bridge 64 with a phase contact 48 is formed. For the control of the power module 11, the capacitor 15 is provided with a driver circuit 49.

[0045] Only schematically shown according to Figure 3The driver circuit 49 is shown in order to describe its function in principle. The driver circuit has a controller function C and a sensor function S. The controller function is ensured by the contact line 51 as an interface to the gates of the first transistor 44 and the second transistor 45. The driver circuit can thus control the two transistors more intelligently as switches. The information required for this function is provided by the sensor function S. The sensor function is ensured by the signal line 52, with which the current can be tapped in front of and behind the capacitor 15 and in front of and behind the phase contact 48 in the half bridge 64.

[0046] The capacitor 15 is connected to the positive electrode 46 and the negative electrode 47, and thus performs the Figure 1 The smoothing function (or filtering function) required for the multi-phase operation of the power electronic circuit 42.

[0047] As in Figure 2 As can be seen in the Figure 2 The power electronic circuit 42. By means of Figure 3 The power modules 11 can be used together in three groups to generate a three-phase AC voltage from the DC voltage present at the common positive pole 46p and the common negative pole 47m, which can be tapped at the common phase contacts 48a, 48b, 48c. The maximum current to be switched determines how many power modules 11 must be used per phase. Figure 2 , each phase uses 10 corresponding power modules 11. Therefore, for each power module 11, Figure 3 A circuit, wherein each group of power modules 11 is connected in parallel.

[0048] Figure 4 A top view of an exemplary embodiment of the present invention is shown, which shows a power module 11 from above. What can be seen is the basic unit above the stack, which includes substrates 12, 13 and solder connections 23 thereon, which surround components 31, such as power chips 50. The power chip 50 can be used as a drain, for example, and in the illustration shown here, the power chip is surrounded by four spacers 17, which are used for potential feedback. Potential feedback is used to provide, in each plane, all electrical connections (also referred to as "potentials") of the installed semiconductor components that exist above and below, i.e. can be intercepted and contacted. Therefore, all functions can be used in each wiring plane, so that "basic units" can be stacked and / or docked.

[0049] The "basic units" form a cell and are assembled as prefabricated, isolated and tested units to form an overall system. The variable configuration that can be achieved in this way provides maximum flexibility during installation, which is combined with maximum surface utilization, which utilizes the available surface by stacking and / or docking the basic units as required.

[0050] Furthermore, the manufacture of the basic unit is suitable for mass production and has all the advantages that come with it.

[0051] Figure 4 The cutting plane AA is also shown. Figure 5 A diagram of a section through this plane AA is shown in .

[0052] Figure 5 A stack of two basic units is shown, which form, for example, a power module 11. Each basic unit comprises components 31, 32, substrates 12, 13, various solder connections 23 and spacers 17. In addition to mechanical stabilization, the spacers 17 can optionally also be used for potential feedback, as described above.

[0053] List of Reference Numerals

[0054] 11 Power Module

[0055] 12. First substrate

[0056] 13. Second substrate

[0057] 15. Capacitor

[0058] 16 Through Holes

[0059] 17 Spacer

[0060] 18 First Base Plate

[0061] 19 Second base plate

[0062] 20 Contact structure

[0063] 21 Cooling structure

[0064] 22 Cooling structure

[0065] 23 Welding connection

[0066] 31 First Device

[0067] 32 Second Device

[0068] 42 Power Electronic Circuits

[0069] 44 First Transistor

[0070] 45 Second transistor

[0071] 46 Positive electrode

[0072] 47 Negative electrode

[0073] 48 phase contacts

[0074] 49 Driving Circuit

[0075] 50 Power Chip

[0076] 51 Contact Line

[0077] 52 signal lines

[0078] 64 Half Bridge

Claims

1. A power module (11) having a first power electronic device (31) arranged on a first substrate (12), characterized in that: A second power electronic component (32) is provided, the second component (32) being mounted on a second substrate (13), wherein the first substrate (12), the first component (31), the second substrate (13) and the second component (32) are arranged on a first base plate in a stacked manner and / or side by side in a planar manner, wherein at least one spacer (17) is arranged between the first substrate (12) and the second substrate (13), the spacer connecting the first substrate (12) and the second substrate (13) to each other, wherein at least one spacer (17) is implemented as conductive and is connected to electrical conductor lines on the first substrate (12) and the second substrate (13), wherein the spacer has a conductive path and is implemented so that the spacer covers and / or represents a signal and / or power path and provides some or all potentials on all planes.

2. The power module (11) according to claim 1, characterized in that: The upper side of the second device (32) is electrically connected to the lower side of the first substrate (12).

3. The power module (11) according to claim 2, characterized in that: The second device (32) is in contact with the first device (31) via an electrical connection path.

4. The power module (11) according to claim 3, characterized in that: The electrical connection path is configured as a metallized through hole in the first substrate (12).

5. The power module (11) according to claim 4, characterized in that: The electrical connection path is configured as a via hole in the first substrate (12).

6. The power module (11) according to claim 3 or 4, characterized in that: The electrical connection path is implemented as a half bridge (64) which provides the phase contacts (48).

7. The power module (11) according to claim 1, characterized in that: The first substrate (12) is connected to the second bottom plate (19).

8. The power module (11) according to claim 1, characterized in that: The first component (31) is connected to the first base plate (18) at the top.

9. The power module (11) according to claim 8, characterized in that: At least one spacer (17a) is arranged between the first substrate (12) and the first bottom plate, and the spacer connects the first substrate (12) and the first bottom plate to each other.

10. The power module (11) according to claim 9, characterized in that: At least one spacer (17a) is electrically conductive and is connected to electrical conductor tracks on the first substrate (12) and the first base plate (18).

11. The power module (11) according to claim 7, characterized in that: The first bottom plate (18) and / or the second bottom plate (19) have cooling structures (21, 22).

12. A power electronic circuit having a plurality of power modules, characterized in that: A power module (11) is constructed according to any one of the preceding claims and is each electrically connected via a base plate.

13. The power electronic circuit according to claim 12, characterized in that: The power module is a converter.

14. The power electronic circuit according to claim 12, characterized in that: The power modules (11) each have two power electronic components (31) which are designed as a first switching element and a second switching element, wherein: The first switching element and the second switching element are combined into a common power connection, The first switching element has a first power connection which is designed as a positive pole (46), and the second switching element has a second power connection which is designed as a negative pole (47).

15. The power electronic circuit according to claim 14, characterized in that: The first switching element and the second switching element are combined into a phase contact (48).

16. The power electronic circuit (42) according to claim 14, characterized in that The power modules (11) are divided into three groups each having the same number of power modules (11), wherein: The first power connections of all switching elements are electrically connected to one another and form a common negative pole (47m), The second power connections of all switching elements are electrically connected to one another and form a common positive pole (46p), In each of the three groups, the common power connections are electrically connected to one another and three common power connections are formed, each having a common phase contact ( 48 a , 48 b , 48 c ).

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