Inverter with a compact structure

Abstract

An inverter (1-4) with a rated power greater than 3 kVA has: a first component comprising a first circuit board (10) and a DC / AC converter stage; and a second component comprising a second circuit board (20) and an EMV filter for the DC / AC converter stage. The first circuit board (10) is mounted on a cooling body (30, 35) and is substantially planar on the cooling body (30, 35). The DC / AC converter stage has a converter component comprising a power semiconductor (12), a choke (13), and an intermediate circuit capacitor (11), wherein the choke (13) and the intermediate circuit capacitor (11) are arranged together on one side of the first circuit board (10), and the cooling body (30, 35) is arranged on the opposite side of the first circuit board (10). The choke (13) and / or power semiconductor (12) are thermally connected to the cooling bodies (30, 35) via a first circuit board (10) and a thermally conductive material (33) disposed between the first circuit board (10) and the cooling bodies (30, 35). A second circuit board (20) is disposed on the side of the first circuit board (10) opposite to the cooling bodies (30, 35). A plate (40) is disposed between the first and second components, and the second circuit board (20) is mounted on the plate (40).

Description

Technical Field

[0001] This invention relates to an inverter with a particularly compact structure. Background Technology

[0002] An inverter is a power electronic device configured to convert between direct current (DC) and alternating current (AC). In particular, inverters are known to feed electrical power from a DC power source (e.g., a photovoltaic generator) into an AC grid, or to bidirectionally exchange electrical power between a DC storage device (e.g., a battery) and the AC grid.

[0003] Known inverters comprise one or more circuit boards containing electrical and electronic components, particularly power semiconductors, in a bridging circuit, as well as capacitors and inductors for generating the desired input or output current of the inverter. The electrical and electronic components can be arranged quite differently within the inverter, with mounting components on circuit boards being common practice. For this purpose, components can be implemented as so-called SMD (Surface Mount Device) components and / or THT (Through-hole Technology) components, where these components can have significantly different characteristics and structural dimensions.

[0004] To cool or dissipate heat from the lossy electrical and electronic components of an inverter, it is known to arrange one or more cooling bodies within or at the inverter. Here, the components to be cooled are in direct or indirect thermal contact with these cooling bodies of the inverter.

[0005] An inverter is known from DE 10 2009 058 270 A1, which has a housing, a water cooler, a power module, a capacitor, and components in a sandwich structure, wherein the components include two circuit boards and a cooling plate, and the capacitor and the power module are arranged between the components and the water cooler.

[0006] An inverter is known from DE 10 2017 127 895 A1, wherein components of the power components of the inverter are arranged on one side of a first circuit board, while the other side of the first circuit board is planarly fixed to a housing wall by means of a clamping device, the housing wall being constructed as part of a cooling device, and wherein a second circuit board having a control unit of the inverter can be arranged on the clamping device. Summary of the Invention

[0007] The objective of this invention is to provide an inverter that has a higher power density than known inverters and is constructed in a more compact and lower cost manner.

[0008] This task is solved by an inverter having the characteristics described below. Preferred embodiments are defined in the following description.

[0009] An inverter with a rated power greater than 3 kVA has a first component and a second component. The first component includes a first circuit board and a DC / AC converter stage. The second component includes a second circuit board and an EMV filter for the DC / AC converter stage. The first circuit board is mounted on a cooling body and is positioned substantially planar on the cooling body.

[0010] The DC / AC converter stage includes a converter component comprising a power semiconductor, a choke, and an intermediate circuit capacitor. The choke and intermediate circuit capacitor are disposed together on one side of a first circuit board, and a coolant is disposed on the opposite side of the first circuit board. The choke and / or power semiconductor are thermally connected to the coolant via the first circuit board and a thermally conductive material disposed between the first circuit board and the coolant, such that the heat loss generated by the choke and / or power semiconductor during inverter operation is substantially dissipated via the coolant.

[0011] The second circuit board is disposed on the side of the first circuit board opposite to the cooling element. The second circuit board is mounted on a plate (Blech) disposed between the first and second components.

[0012] Dividing the inverter components into two modules enables a compact structure. Specifically, placing the first circuit board containing the DC / AC converter stage on a cooling body ensures excellent heat dissipation for the components responsible for most of the heat loss generated during inverter operation. The second circuit board and the components arranged on it achieve exceptionally high power density through heat dissipation via the plates between the modules. Furthermore, the plates provide mechanical stabilization and shielding functions: preventing crosstalk between components, shielding the converter components from external electromagnetic fields, and protecting the surrounding environment from electromagnetic radiation from the converter components.

[0013] This invention is based on the understanding that, due to technological advancements, highly efficient topologies can be used in inverters, characterized by the ability to design relatively small converter components (e.g., intermediate circuit capacitors and chokes) for stable operation. In particular, three-phase topologies are considered for this purpose, such as the so-called B6 bridge circuit and the so-called FlyingCap topology, which can be implemented not only as single-phase but also as three-phase.

[0014] Therefore, even for rated power greater than 3kVA, the intermediate circuit capacitors and chokes arranged on the first circuit board, as well as any additional converter components (e.g., filter capacitors and / or current sensors), can all be implemented as SMD components. Alternatively or additionally, the individual converter components can also be implemented as a circuit board integrated structure, for example, as a planarspule, which can be formed by the conductor lines of the circuit board itself.

[0015] In an alternative implementation, the power semiconductor and choke can be implemented as SMD components, while the intermediate circuit capacitor is implemented as a THT component. Therefore, a larger intermediate circuit capacitor can be implemented if needed. However, the THT component has a connecting line that extends through the circuit board carrying the THT component and makes an electrical contact on the side opposite the THT component, for example, by soldering electrical contacts. Therefore, the connecting line of the THT component disposed on the first circuit board extends into the space between the first circuit board and the cooling element.

[0016] Preferably, the cooling body has a substantially flat cooling surface, which includes, for example, a base plate of an extruded aluminum cooling body. Since the first circuit board is substantially planar on the cooling body, it has been proven advantageous for planar thermal connections between the first circuit board and the THT component if the cooling surface of the cooling body facing the first circuit board has an aussparung (or recessed aussparung) at the location of the connecting lines. The aussparung ensures a sufficiently large gap between the connecting lines of the THT component and the cooling body, and thus ensures their electrical insulation relative to each other.

[0017] The cooling body may include an extruded profile having heat sinks arranged along the pressing direction. It has proven advantageous to implement the openings in the substantially flat cooling surface of the extruded profile as groove-shaped recesses, allowing connecting lines to extend into these recesses. Preferably, the groove-shaped recesses can extend parallel to the heat sinks of the cooling body, and are therefore particularly simple to incorporate during the manufacturing of the extruded profile, enabling low-cost manufacturing of the cooling body.

[0018] Alternatively or additionally, the recesses can be arranged individually, for example, as milled grooves on the cooling surface, at the corresponding locations of the THT components or at the locations of the connecting lines of the THT components. Here, the corresponding diameter of the recess can be designed such that exactly one connecting line of the THT component is arranged in each recess. When a manageable number of THT components are arranged on the first circuit board, for example, about a dozen, individual recesses can be allocated to all connecting lines of all THT components on the first circuit board, for example, by milling the surface of the coolant point by point at the location of the connecting lines. Overall, the cooling surface of the coolant is thus optimally used for heat dissipation, particularly from the first assembly.

[0019] Alternatively or additionally, the diameter of this clearance can be designed such that all the connecting wires of exactly one THT component are arranged in a common clearance. The diameter of this common clearance is larger than the diameter of the clearances individually allocated to the connecting wires, yet it occupies only a small portion of the total surface area of ​​the coolant, thus allowing the vast majority of the coolant's surface to be thermally optimally connected to the first circuit board.

[0020] Needless to say, a predetermined insulation distance may need to be maintained between the connecting wire and the cooling element. Furthermore, the gap may be lined with a thin electrical insulating material to ensure insulation between the connecting wire and the cooling element.

[0021] In one embodiment of the inverter according to the invention, the spacing between the circuit boards is less than five centimeters, and preferably less than three centimeters. This allows for a particularly compact structure that follows the structural height of the SMD components and takes full advantage of equipping the first circuit board with SMD components.

[0022] In another embodiment of the inverter according to the invention, the average distance between the first circuit board and the cooling surface of the cooling body is less than one centimeter, and preferably less than five millimeters. Considering that the thermally conductive material bridges the minimum distance required in any structure, the circuit board is thus in direct thermal contact with the cooling body. This ensures ideal thermal connection between the circuit board, and therefore the first component, to the cooling surface and thus to the cooling body.

[0023] The power semiconductor of the first component can be arranged on the side of the first circuit board facing the coolant to achieve direct thermal connection between the power semiconductor and the coolant. It has proven advantageous to provide a gap in the cooling surface of the coolant at the location of the power semiconductor, such that the distance between the circuit board and the power semiconductor and the cooling surface is substantially the same; that is, for example, the circuit board and the power semiconductor are thermally coupled to the coolant using the same thermally conductive material. Thus, the depth of the gap relative to the cooling surface is specifically equal to the structural height of the power semiconductor.

[0024] In one embodiment, the second component of the inverter has a filter component arranged on the side of the second circuit board opposite to the first circuit board.

[0025] In one embodiment of the inverter according to the invention, the first component has at least two chokes thermally connected to the plate via a thermally conductive material disposed between the chokes and the plate. Alternatively or additionally, at least one intermediate circuit capacitor of the first component may be thermally connected to the plate via a thermally conductive material disposed between the intermediate circuit capacitor and the plate. The thermal connection of the chokes and / or intermediate circuit capacitors to the cooling element further improves heat dissipation of the converter components via the plate.

[0026] In addition, the inverter may have a ventilation device that generates an airflow along the plate between the first and second components, thereby contributing to the optimal removal of the inverter's heat loss.

[0027] The plates between the components are generally parallel to the circuit board orientation and may further have sections extending from the plane of the plates and into the structural space of the first component. These sections not only contribute to the stability of the plates but also help improve the cooling efficiency of the plates, especially when the sections are captured by the airflow of the ventilation device, and can also guide the airflow in a targeted manner.

[0028] In another embodiment of the inverter according to the invention, the first component includes a DC / DC converter stage, wherein the DC / DC converter stage is connected to the DC / AC converter stage via an intermediate circuit capacitor. This, in particular, expands the usable range of the inverter's input voltage. The power semiconductor of the DC / DC converter stage can be implemented as silicon carbide or gallium nitride semiconductors. Furthermore, the power semiconductor of the DC / AC converter stage can be implemented as silicon carbide or gallium nitride semiconductors.

[0029] The first component of the inverter according to the invention may include a control unit disposed on a first circuit board and configured to drive power semiconductors by means of a pulse-width modulated clock signal and to detect current and voltage measurements of the DC / AC converter stage. Specifically, the control unit may be configured to switch the power semiconductors at a switching frequency of at least 100 kHz. Furthermore, the DC / AC converter stage of the inverter may include at least two half-bridges, wherein the control unit is configured to periodically switch the power semiconductors of the two half-bridges with a phase offset of at least 90 degrees relative to the switching cycle.

[0030] The use of silicon carbide or gallium nitride power semiconductors, combined with high switching frequencies, and, where necessary, phase-shifting nesting of the clocks of multiple parallel half-bridges in the DC / AC converter stage, enables the generation of low-distortion current profiles at the half-bridge outputs, before they are smoothed by the chokes. This allows both the chokes and intermediate circuit capacitors to be designed to be smaller, or to achieve higher power ratings with the same design.

[0031] The inverter according to the invention can be configured to exchange power from at least one connectable DC voltage unit with a low-voltage grid phase line via a DC / AC converter stage and an EMV filter. Specifically, the inverter can feed power into and / or extract power from the low-voltage grid according to standards. In one embodiment, the inverter is implemented as three-phase and configured to exchange power with a three-phase low-voltage grid on all three phases. Specifically, the DC voltage unit at the inverter's DC input may include a photovoltaic generator and / or a battery. Attached Figure Description

[0032] The present invention will now be further described and illustrated based on the embodiments shown in the accompanying drawings.

[0033] Figure 1 An inverter according to the first embodiment is shown.

[0034] Figure 2 An inverter in the second embodiment is shown.

[0035] Figure 3 The inverter in the third embodiment is shown.

[0036] Figure 4 An embodiment of a cooling element for an inverter is shown, and

[0037] Figure 5 An inverter according to a fourth embodiment is shown. Detailed Implementation

[0038] Figure 1 Inverter 1 is shown in a simplified cross-sectional view. The power electronic components of inverter 1 are shown. It goes without saying that for the actual operation of the inverter, such as as a battery inverter or photovoltaic inverter supplying power to a load or feeding power into the AC grid, additional electrical, electromechanical, and mechanical components are required. For clarity, these are shown in... Figure 1 These components are not shown. In particular, they include DC and AC connection devices, relays, housings, etc.

[0039] Inverter 1 includes a first circuit board 10 and a second circuit board 20. The first circuit board 10 is mounted on a cooling body 30. The cooling body 30 includes a substantially flat cooling surface 31 and heat sinks 32 disposed thereon, wherein the heat sinks 32 are spaced apart from each other so that cooling air can flow between the heat sinks 32 (compare). Figure 2 A thermally conductive material 33 is disposed between the first circuit board 10 and the cooling surface 31. The thermally conductive material 33 may be constructed as a single piece and cover the entire support surface of the first circuit board 10 on the cooling body 30. Alternatively, the thermally conductive material 33 may consist of multiple parts and / or an adhesive substance, wherein only a portion of the support surface may be covered.

[0040] Different power electronic converter components are arranged on the first circuit board 10, which together form a DC / AC converter stage. Specifically, the DC / AC converter stage includes an intermediate circuit capacitor 11, a power semiconductor 12, and a choke 13, as well as other peripheral components, such as, in particular, a control unit 14 and other drivers, controllers, and / or other electronic devices (resistors, ICs, etc.).

[0041] Specifically, the components on the first circuit board 10 can be implemented as surface-mount devices (SMD components). In particular, SMD components are characterized in that the SMD component is electrically contacted with the conductive lines of the circuit board on the side on which the component is disposed, thus eliminating the need to access the side of the circuit board away from the component to mount the SMD component. Conversely, so-called THT components, which are provided for through-hole mounting (THT = Through-Hole Technology), are electrically contacted with the conductive lines of the circuit board on the side of the circuit board away from the THT component, especially through soldering.

[0042] If based on Figure 1 Since no THT components are arranged on the first circuit board 10, the circuit board 10 can be thermally connected to the cooling surface 31 across its entire surface by a thermally conductive material 33. Here, the thermally conductive material 33 is typically made as thin as possible to ensure that the thermal resistance between the first circuit board 10 and the cooling body 30 is as small as possible. The thermal resistance is formed, as far as possible, solely by the thermally conductive material 33, rather than by, for example, air, which has a significantly higher thermal resistance. Thus, the heat loss generated in the converter components 11-13 during inverter 1 operation is effectively conducted through the first circuit board 10 and via the thermally conductive material 33 to the cooling body 30 and from the cooling body to the surrounding environment.

[0043] Various other components of the inverter 1 are arranged on the second circuit board 20, specifically forming an EMV filter for the DC / AC converter stage on the second circuit board 20. Specifically, the EMV filter includes a filter capacitor 21 and a filter choke 22, wherein another filter capacitor 21 may be arranged on the first circuit board 10. Additionally, a communication processor 23 is arranged on the second circuit board, for example. Electrical connections 50 (e.g., cables or busbars) connected to connection elements 51 (e.g., sockets or screw clamps) connect the DC / AC converter stage on the first circuit board 10 to the EMV filter on the second circuit board 20. Here, the connections 50 are designed such that they can generally transmit electrical power corresponding to at least the rated power of the inverter 1. Furthermore, suitable signal lines for transmitting internal control and operation signals may be arranged between circuit boards 10 and 20.

[0044] The second circuit board 20 is mounted (e.g., screwed or clamped) on the plate 40 by means of a fixing device 41. The plate 40 is located on the intermediate circuit capacitor 11 and the choke 13, wherein a thermally conductive material 43 is arranged between the plate 40 and the intermediate circuit capacitor 11 or the choke 13. This specifically determines the position of the plate 40, and thus also the position of the second circuit board 20. Additionally, another retaining plate 42 may be provided, which allows the plate 40 to be directly mechanically connected to the first circuit board 10. During the operation of the inverter 1, the heat loss generated in the intermediate circuit capacitor 11 and the choke 13 is effectively conducted to the plate 40 via the thermally conductive material 43 and effectively conducted from the plate 40 to the surrounding environment.

[0045] Figure 2 Another inverter 2 is shown in a simplified cross-sectional view. It has already been combined... Figure 1 The basically identical components described are given the same reference numerals.

[0046] Multiple intermediate circuit capacitors 11, power semiconductors 12, and chokes 13 are arranged on the first circuit board 10 as components of the DC / AC converter stage. In particular, the DC / AC converter stage, and therefore the inverter 2, can be implemented as a three-phase system, wherein components 12 and 13 are also implemented as triplicate, and a pair of power semiconductors 12 can form a half-bridge of one phase of the three-phase inverter 2.

[0047] If the components of the DC / AC converter stage are primarily designed as SMD components and, in particular, no THT components are arranged on the first circuit board 10, the first circuit board 10 is thermally connected to the cooling surface 31 across its entire surface via a thermally conductive material 33. This ensures that the heat loss generated in the components 11, 12, and 13 on the first circuit board 10 is effectively dissipated to the cooling body 30 and then from the cooling body to the surrounding environment.

[0048] Other components of the inverter 2 are arranged on the second circuit board 20, particularly an EMV filter including a filter capacitor 21 and a filter choke 22, and a communication processor 23. Of course, an electrical connection is provided between circuit boards 10 and 20 (see...). Figure 1 However, for the sake of clarity, Figure 2 Not shown in the image.

[0049] A plate 40 is arranged between the first circuit board 10 and the second circuit board 20. The second circuit board 20 is fixed to the plate 40. The plate 40 is located on the intermediate circuit capacitor 11 and the choke 13, thus defining the position of the plate 40 and consequently the position of the second circuit board 20. A thermally conductive material 43 is arranged between the plate 40 and the intermediate circuit capacitor 11 or the choke 13. Thus, during the operation of the inverter 2, a portion of the heat dissipated by the intermediate circuit capacitor 11 and the choke 13 is introduced into the plate 40 via the thermally conductive material 43 and dissipated from the plate 40 to the surrounding environment.

[0050] Figure 3 Another inverter 3 is shown in a simplified cross-sectional view. It has already been combined... Figure 1 or Figure 2 The essentially identical components described are provided with the same reference numerals. Inverter 3 includes a first circuit board 10 and a second circuit board 20. The first circuit board 10 is mounted on a cooling body 35.

[0051] The inverter 3's cooling body 35 has a cooling surface 34, which includes substantially flat surface sections, with most of the cooling surface 34 located in a first plane. However, at least one of the surface sections of the cooling surface 34 is located in a second plane, thus the cooling body 35 has grooves 36. The cooling body 34 includes heat sinks 32 through which the heat dissipated by the inverter 3 is released to the surrounding environment.

[0052] A DC / AC converter stage is arranged on the first circuit board 10, which specifically includes an intermediate circuit capacitor 61, a power semiconductor 12, and a choke 13. (This is in accordance with...) Figure 1 or Figure 2 Unlike inverters 1 and 2, inverter 1 now also has THT components arranged on the first circuit board 10, particularly the intermediate circuit capacitor 61. The intermediate circuit capacitor 61 has a connecting wire 62 that extends through the circuit board 10 and is fixed to the side of the circuit board 10 opposite to the component, primarily by means of soldering. Furthermore, the control unit 14 and, if necessary, additional capacitors 15 are arranged on the first circuit board 10; these are preferably implemented as SMD components.

[0053] Therefore, the first circuit board 10 has an area where the THT component is disposed. The connecting line 62 of the intermediate circuit capacitor 61, implemented as the THT component, extends through the first circuit board 10. Due to the connecting line 62, the first circuit board 10 is not easily fully placed on the cooling surface 34 in the area of ​​the THT component. More precisely, the THT component needs to have a distance between the first circuit board 10 and the cooling surface 34. Figure 3 This is achieved through trench 36. The depth of trench 36 is designed to ensure electrical insulation between the connecting wire 62 and the cooling body 35.

[0054] On the other hand, the first circuit board 10 has a wide area in which THT components are arranged. Components are specifically arranged in these areas of the circuit board 10. These areas without THT components are planarly thermally connected to the cooling surface 34 via a thermally conductive material 33. In particular, components that generate relatively more heat loss are arranged in these areas, so that the heat loss of the power semiconductor 12, the choke 13, and, if necessary, the capacitor 15 is effectively conducted through the first circuit board 10 and via the thermally conductive material 33 to the cooling body 35 and from the cooling body to the surrounding environment.

[0055] A plate 40 is arranged between the first circuit board 10 and the second circuit board 20. The second circuit board 20 is fixed on the plate 40. The plate 40 is located on the intermediate circuit capacitor 61 and the choke 13, thus determining the position of the plate 40 and consequently the position of the second circuit board 20.

[0056] A thermally conductive material 43 is disposed between the plate 40 and the intermediate circuit capacitor 61 or choke 13. Thus, during the operation of the inverter 3, the heat dissipated by the intermediate circuit capacitor 61 and choke 13 is introduced into the plate 40 via the thermally conductive material 43 and dissipated from the plate 40 to the surrounding environment. Additionally, a guide plate 44 may be provided, which guides airflow, for example driven by a ventilation device, through the intermediate space between the first circuit board 10 and the plate 40. Furthermore, the plate 40 can be mechanically connected directly to the first circuit board 10 via a retaining plate 42 (see reference). Figure 1 ).

[0057] Figure 4 A cooling body 35 suitable for use in inverters 1, 2, and 3 is shown. The cooling body 35 is shown in different views in sub-figures a), b), and c), where a) shows a perspective view, b) shows a top view of the cooling surface 37, and c) shows a cross-section along line AA in a) and b). The cooling body 35 has a cooling surface 37 and heat sinks 32. Multiple recesses 38 are introduced into the cooling surface 37, for example, by milling. Additionally, it is possible to provide... Figure 3 Groove 36, in Figure 4 Not shown for clarity.

[0058] Specifically, the first circuit board 10 can be mounted on the cooling body 35, according to... Figure 3 THT components (e.g., intermediate circuit capacitor 61, or, if necessary, power semiconductor 12 and / or choke 13 of THT structure type) are arranged on the first circuit board 10. Recesses 38 are arranged on the cooling surface 37 such that the recesses 38 coincide with the positions of the connection lines 62 of the THT components. Additionally, an insulating layer 39 can be introduced into the corresponding bottom of the recesses 38. This ensures sufficient electrical insulation between the cooling body 35 and the potential on the first circuit board 10.

[0059] Figure 5 Another inverter, 4, is shown in a simplified cross-sectional diagram. It has already been combined... Figures 1 to 3 The essentially identical components described are provided with the same reference numerals. Inverter 4 includes a first circuit board 10 and a second circuit board 20. The first circuit board 10 is mounted on a cooling body 35. Intermediate circuit capacitor 11 and choke 13 are arranged on the first circuit board 10 and are implemented as SMD components.

[0060] The inverter 4's cooling body 35 has a cooling surface 34, which includes substantially flat surface sections, with most of the cooling surface 34 located in a first plane. However, two surface sections of the cooling surface 34 are located in a second plane, thus the cooling body 35 has two recesses 38. The cooling body 35 includes heat sinks 32, through which the heat dissipated by the inverter 4 is released to the surrounding environment.

[0061] A power semiconductor 12 is disposed on a first circuit board 10. The power semiconductor 12 is mounted on the side of the first circuit board 10 facing the coolant 35. Here, the power semiconductor 12 is located at the recess 38. Thus, the first circuit board 10 can be placed substantially planar and is well thermally connected to the cooling surface 34 of the coolant 35 via a thermally conductive material 33, while the power semiconductor 12 is disposed directly in the "recessed" cooling surface 34 in the recess 38 and is therefore optimally thermally connected to the coolant 35. Needless to say, a thermally conductive material can be disposed between the power semiconductor 12 and the coolant 35 for this purpose.

[0062] Reference tag list

[0063] Inverters 1, 2, 3, and 4

[0064] 10, 20 circuit boards

[0065] 11. Intermediate circuit capacitor

[0066] 12 Power Semiconductors

[0067] 13. Choke

[0068] 14 Control Unit

[0069] 15 capacitors

[0070] 21 Filter capacitor

[0071] 22 Filter choke

[0072] 23 Communication Processor

[0073] 30, 35 cooling body

[0074] Cooling surfaces 31, 34, and 37

[0075] 32 heat sinks

[0076] 33 Thermally conductive materials

[0077] 38 recess

[0078] 39 Insulation layer

[0079] 40 Sheet

[0080] 41 Fixed mechanism

[0081] 42 Retention Plate

[0082] 43 Thermally conductive materials

[0083] 44 Guide Board

[0084] 50 Connectors

[0085] 51 Connecting elements

[0086] 61 Intermediate Circuit Capacitor

[0087] 62 Connecting wires.

Claims

1. An inverter with a rated power of at least 3 kVA, comprising: A first component, comprising a first circuit board (10) and a DC / AC converter stage; and a second component, comprising a second circuit board (20) and an EMV filter for the DC / AC converter stage, wherein the first circuit board (10) is mounted on a cooling body and is planarly disposed on the cooling body, wherein the DC / AC converter stage has a converter component comprising a power semiconductor (12), a choke (13), and an intermediate circuit capacitor (11), wherein the choke (13) and the intermediate circuit capacitor (11) are jointly arranged on the first circuit board (20). The first circuit board (10) is located on one side of the first circuit board (10), and the cooling body is arranged on the opposite side of the first circuit board (10), wherein the choke (13) and / or the power semiconductor (12) are thermally connected to the cooling body via the first circuit board (10) and a thermally conductive material (33) arranged between the first circuit board (10) and the cooling body, wherein the second circuit board (20) is arranged on the opposite side of the first circuit board (10) to the cooling body, wherein a plate (40) is arranged between the first component and the second component, and the second circuit board (20) is mounted on the plate (40). Its features are, At least one choke (13) of the first component and at least one intermediate circuit capacitor (11) of the intermediate circuit capacitor are thermally connected to the plate (40) via a thermally conductive material (43) disposed between the plate (40) and the choke (13) and / or between the plate (40) and the intermediate circuit capacitor (11).

2. The inverter according to claim 1, wherein, The converter component also includes a filter capacitor (21) and / or a current sensor, which are arranged on the first circuit board (10).

3. The inverter according to claim 1, wherein, All converter components are implemented as SMD components or integrated into the first circuit board (10).

4. The inverter according to claim 2, wherein, All converter components are implemented as SMD components or integrated into the first circuit board (10).

5. The inverter according to claim 1, wherein, The power semiconductor (12) and the choke (13) are implemented as SMD components, wherein the intermediate circuit capacitor (11) is implemented as a THT component.

6. The inverter according to claim 2, wherein, The power semiconductor (12) and the choke (13) are implemented as SMD components, wherein the intermediate circuit capacitor (11) is implemented as a THT component.

7. The inverter according to claim 5 or 6, wherein, The connecting line (62) of the THT component arranged on the first circuit board (10) extends into the space between the first circuit board (10) and the cooling body, wherein the cooling surface of the cooling body facing the first circuit board (10) has a gap at the location of the connecting line (62), thereby ensuring that the installable connecting line (62) and the cooling body are electrically insulated from each other.

8. The inverter according to claim 7, wherein, The cooling body includes an extruded profile, wherein the void includes a groove (36) in the cooling surface of the extruded profile, such that the connecting line (62) extends into the groove (36).

9. The inverter according to claim 8, wherein, The cooling body has a plurality of heat sinks (32), wherein the grooves (36) are oriented parallel to the heat sinks (32).

10. The inverter according to claim 7, wherein, The void includes a plurality of recesses (38) in the cooling surface of the cooling body, wherein the diameter of the recesses (38) is designed such that exactly one connecting line (62) of the THT component or exactly one connecting line (62) of the THT component is arranged in one of the recesses (38), wherein a predetermined insulating distance is maintained between the connecting line (62) and the cooling body.

11. The inverter according to any one of claims 1-6 and 8-10, wherein, The distance between the first circuit board (10) and the second circuit board (20) is less than five centimeters.

12. The inverter according to claim 11, wherein, The distance between the first circuit board (10) and the second circuit board (20) is less than three centimeters.

13. The inverter according to any one of claims 1-6, 8-10 and 12, wherein, The distance between the first circuit board (10) and the cooling surface of the cooling body is less than one centimeter.

14. The inverter according to claim 13, wherein, The distance between the first circuit board (10) and the cooling surface of the cooling body is less than 5 mm.

15. The inverter according to any one of claims 1-6, 8-10, 12 and 14, wherein, The power semiconductor (12) is arranged on the side of the first circuit board (10) facing the cooling body and is in direct thermal contact with the cooling body.

16. The inverter according to claim 15, wherein, The cooling surface of the cooling body has a gap at the position of the power semiconductor (12), such that the first circuit board (10) and the power semiconductor (12) have the same distance relative to the cooling surface.

17. The inverter according to any one of claims 1-6, 8-10, 12, 14 and 16, wherein, The second component has a filter element arranged on the side of the second circuit board (20) opposite to the first circuit board (10).

18. The inverter according to any one of claims 1-6, 8-10, 12, 14 and 16, wherein, The inverter has a ventilation device that generates an airflow along the plate (40) between the first component and the second component.

19. The inverter according to any one of claims 1-6, 8-10, 12, 14 and 16, wherein, The plate (40) has a retaining plate (42) and / or a guide plate (44) extending from the plane of the plate (40) and into the structural space of the first component.

20. The inverter according to any one of claims 1-6, 8-10, 12, 14 and 16, wherein, The first component includes a DC / DC converter stage, wherein the DC / DC converter stage is connected to the DC / AC converter stage via the intermediate circuit capacitor (11).

21. The inverter according to claim 20, wherein, The power semiconductor (12) of the DC / DC converter stage is implemented as a silicon carbide semiconductor or a gallium nitride semiconductor.

22. The inverter according to any one of claims 1-6, 8-10, 12, 14, 16 and 21, wherein, The power semiconductor (12) of the DC / AC converter stage is implemented as a silicon carbide semiconductor or a gallium nitride semiconductor.

23. The inverter according to any one of claims 1-6, 8-10, 12, 14, 16 and 21, wherein, The first component includes a control unit (14) disposed on the first circuit board (10) and configured to drive the power semiconductor (12) by means of a pulse-width modulated clock signal and to detect current and voltage measurements of the DC / AC converter stage.

24. The inverter according to claim 23, wherein, The control unit (14) is configured to switch the power semiconductor (12) at a switching frequency of at least 100 kHz.

25. The inverter according to claim 23, wherein, The DC / AC converter stage includes at least two half-bridges, wherein the control unit (14) is configured to periodically switch the power semiconductors (12) of the two half-bridges with a phase offset of at least 90 degrees relative to the switching cycle.

26. The inverter according to claim 24, wherein, The DC / AC converter stage includes at least two half-bridges, wherein the control unit (14) is configured to periodically switch the power semiconductors (12) of the two half-bridges with a phase offset of at least 90 degrees relative to the switching cycle.

27. The inverter according to any one of claims 1-6, 8-10, 12, 14, 16, 21 and 24-26, wherein, The inverter is configured to exchange the electrical power of at least one connectable DC voltage unit with the phase line of the low-voltage grid via the DC / AC converter stage and the EMV filter.

28. The inverter according to any one of claims 1-6, 8-10, 12, 14, 16, 21 and 24-26, wherein, The inverter is configured to feed electrical power into and / or extract electrical power from the low-voltage grid in accordance with standards.

29. The inverter according to any one of claims 1-6, 8-10, 12, 14, 16, 21 and 24-26, wherein, The inverter is implemented as a three-phase inverter and is configured to exchange power with the three-phase low-voltage grid on all three phases.

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