Power module for three-level converter and three-level converter

Abstract

The utility model provides a power module for a three-level converter and the three-level converter. The power module includes: a heat dissipation plate having a first heat dissipation surface; a first IGBT unit disposed on the heat dissipation plate and including first to third IGBT groups, the first IGBT group including two or more first IGBT modules connected to each other in parallel, the second IGBT group including two or more second IGBT modules connected to each other in parallel, the third IGBT group including two or more third IGBT modules connected to each other in parallel, and the first IGBT unit including first to third IGBT groups connected to each other in parallel; each IGBT module includes two IGBTs connected in series with each other, and the first to third IGBT modules are linearly arranged on the first heat dissipation surface along the length direction of the heat dissipation plate. According to the power module provided by the utility model, the output power can be improved under the same boundary dimension.

Description

Technical Field

[0001] The utility model relates to the field of wind power generation, in particular to a power module for a three-level converter and a three-level converter. Background Art

[0002] With the widespread application of wind power generation, the capacity of wind turbines has been continuously improved, so the high-power wind turbines have become a development trend. Since the conversion between AC and DC between wind turbines and the power grid is achieved through converters, high-power converters are required to achieve high power of wind turbines.

[0003] As one of the important components to realize the function of the converter, the performance of the power module affects the performance of the converter and even the wind turbine. Therefore, more and more research focuses on the power module. Utility Model Content

[0004] The utility model aims to provide a power module for a three-level converter and a three-level converter, wherein the power module can increase output power under the same external dimensions.

[0005] According to one aspect of the utility model, a power module for a three-level converter is provided, the power module comprising: a heat sink having a first heat dissipation surface; a first IGBT unit (120) arranged on the heat sink and comprising a first IGBT group, a second IGBT group and a third IGBT group, the first IGBT group comprising two or more first IGBT modules connected in parallel to each other, the second IGBT group comprising two or more second IGBT modules connected in parallel to each other, the third IGBT group comprising two or more third IGBT modules connected in parallel to each other, wherein each of the two or more first IGBT modules, the two or more second IGBT modules and the two or more third IGBT modules comprises two IGBTs connected in series to each other, and the two or more first IGBT modules, the two or more second IGBT modules and the two or more third IGBT modules are arranged in a straight line on the first heat dissipation surface along the length direction of the heat sink.

[0006] Preferably, the heat sink may have a liquid inlet and a liquid outlet, so that the coolant flowing in through the liquid inlet dissipates heat for the first IGBT unit arranged on the heat sink and then flows out from the liquid outlet.

[0007] Preferably, the power module may further include a first stacked DC busbar, which includes a stacked neutral busbar, a positive busbar and a negative busbar, and is disposed on a first side of the first IGBT unit.

[0008] Preferably, the first connecting terminals of the two or more first IGBT modules can be connected to the positive busbar, the second connecting terminals of the two or more first IGBT modules can be connected to the neutral busbar, the first connecting terminals of the two or more third IGBT modules can be connected to the neutral busbar, the second connecting terminals of the two or more third IGBT modules can be connected to the negative busbar, the first connecting terminals of the two or more second IGBT modules can be connected to the node between the two IGBTs of each of the two or more first IGBT modules, and the second connecting terminals of the two or more second IGBT modules can be connected to the node between the two IGBTs of each of the two or more third IGBT modules.

[0009] Preferably, the power module may further include a first AC busbar, which is arranged on a second side of the first IGBT unit opposite to the first side, wherein a node between two IGBTs of each of the two or more second IGBT modules can be connected to the first AC busbar.

[0010] Preferably, the power module may further include: a first adapter board, which is disposed on the first IGBT unit and is configured to drive the first IGBT unit; and a first circuit board, which is disposed on the first adapter board.

[0011] Preferably, the power module may further include a second IGBT unit, which is disposed on a second heat dissipation surface of the heat dissipation plate opposite to the first heat dissipation surface and has a structure symmetrical to the first IGBT unit based on the heat dissipation plate.

[0012] Preferably, the power module may also include a second adapter board, a second circuit board, a second stacked DC busbar and a second AC busbar, and the second adapter board, the second circuit board, the second stacked DC busbar and the second AC busbar are symmetrically arranged with the first adapter board, the first circuit board, the first stacked DC busbar and the first AC busbar about the heat sink.

[0013] Preferably, the power module may further include a shell, the shell including a base and a top plate and a side plate connected via the base and the top plate, the top plate and the base respectively having a plurality of through holes, wherein the first IGBT unit and the second IGBT unit are installed in the shell.

[0014] According to one aspect of the utility model, a three-level converter is provided. The three-level converter comprises the power module and an absorption capacitor as described above, wherein an AC side of the power module is connected to the absorption capacitor.

[0015] According to the power module for the three-level converter of the utility model, three IGBT groups are formed by IGBT modules connected in parallel, and the IGBT modules are arranged in a straight line, so the output power can be increased under the same external dimensions.

[0016] In addition, the power module for a three-level converter according to the utility model sets the IGBT modules symmetrically with respect to the heat sink, so that more IGBT modules can be arranged to achieve structural optimization, further improving the output power and making the power module have excellent reliability.

[0017] In addition, the three-level converter according to the present invention can have high output power and low failure rate, and thus can operate stably for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other aspects, features and advantages of the present invention will become clear and more easily understood through the following detailed description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0019] Figure 1 is a schematic diagram showing the structure of a power module according to an embodiment of the utility model;

[0020] Figure 2 is a schematic diagram showing the structure of a power module according to an embodiment of the utility model after removing the side plate of the housing;

[0021] Figure 3 It is shown Figure 1 A topological diagram of the power module; and

[0022] Figure 4 It is shown Figure 1 A schematic diagram of the connection between the first IGBT unit and the first DC stacked busbar in the power module.

[0023] Reference Numbers

[0024] 100-power module; 110-heat sink; 111-liquid inlet; 112-liquid outlet; 120-first IGBT unit; 121-first IGBT module A; 122-second IGBT module B; 123-third IGBT module C; 124-first IGBT module D; 125-second IGBT module E; 126-third IGBT module F; 140-housing; 141-first side panel; 142-second side panel; 143-top panel; 144-base; 150-first adapter board; 160-first circuit board; 170-first A stack of DC busbars; 171-neutral busbar; 171h-neutral mounting hole; 172-positive busbar; 172h-positive mounting hole; 173-negative busbar; 173h-negative mounting hole; 180-first AC busbar; 180h-AC mounting hole; D11, D12, D21, D22, D31, D32, D41, D42, D51, D52, D61, D62-diodes; T11, T12, T21, T22, T31, T32, T41, T42, T51, T52, T61, T62-transistors. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical concept of the present invention, specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. In the accompanying drawings, the same reference numerals always represent the same or similar elements.

[0026] It will be understood that although terms such as "first", "second", etc. may be used herein to describe various elements, these elements will not be limited by these terms. Rather, these terms are only used to distinguish one element from another element. Therefore, without departing from the teachings of the exemplary embodiments described herein, the first element referred to in the exemplary embodiments may also be referred to as the second element.

[0027] For ease of description, the terms “inside”, “outside”, “upper” and “lower” referred to below are consistent with the inside, outside, upper and lower directions of the drawings themselves, but do not limit the structure of the present invention.

[0028] In addition, throughout the specification, when an element is described as being “disposed on,” “connected to,” or “coupled to” another element, the element may be directly “disposed on,” “connected to,” or “coupled to” the other element, or one or more other elements may be interposed therebetween.

[0029] In the following, reference will be made to Figures 1 to 3 The power module according to the embodiment of the present utility model is described in detail.

[0030] Figure 1 is a schematic diagram showing the structure of a power module according to an embodiment of the utility model, Figure 2 is a schematic diagram showing the structure of a power module according to an embodiment of the utility model after removing the side plate of the housing, Figure 3 It is shown Figure 1 The topology diagram of the power module, and Figure 4 It is shown Figure 1 A schematic diagram of the connection between the first IGBT unit and the first DC stacked busbar in the power module.

[0031] like Figures 1 to 4 As shown, the power module 100 for a three-level converter according to the embodiment may include a heat sink 110 and a first IGBT unit 120 .

[0032] The first IGBT unit 120 may be disposed on the heat dissipation plate 110 and may include a first IGBT group, a second IGBT group, and a third IGBT group. The first IGBT group may include two or more first IGBT modules connected in parallel to each other, the second IGBT group may include two or more second IGBT modules connected in parallel to each other, and the third IGBT group may include two or more third IGBT modules connected in parallel to each other.

[0033] Each of the two or more first IGBT modules, the two or more second IGBT modules, and the two or more third IGBT modules may include two IGBTs connected in series. In addition, the heat sink 110 may have a first heat dissipation surface, and the two or more first IGBT modules, the two or more second IGBT modules, and the two or more third IGBT modules may be arranged in a straight line on the first heat dissipation surface along the length direction of the heat sink 110.

[0034] Specifically, in the present embodiment, the heat sink 110 is a liquid cooling plate. Specifically, the heat sink 110 may include a liquid inlet 111 and a liquid outlet 112. Although not shown, the heat sink 110 may also include a cooling liquid channel. Therefore, the cooling liquid may flow in from the liquid inlet 111, flow along the cooling liquid channel, and finally flow out from the liquid outlet 112, thereby dissipating the heat of the device disposed on the heat sink 110. In order to fully dissipate the heat of the device disposed on the heat sink 110, the internal structure and the external structure of the heat sink 110 may be adjusted as needed. It should be understood that in addition to the liquid cooling plate, the heat sink 110 may also be other types of heat sinks.

[0035] In the present invention, the IGBT module can be based on PrimePACK TM 3 packaging, but not limited to this. For example, IGBT modules can also be used with PrimePACK TM3. Therefore, each IGBT module can have lower stray inductance, contact thermal resistance and higher operating junction temperature, and can have stronger current carrying capacity and excellent mechanical strength and vibration resistance.

[0036] For ease of understanding, the following description takes the case where the first IGBT group, the second IGBT group and the third IGBT group respectively include two first IGBT modules, two second IGBT modules and two third IGBT modules as an example, and the two first IGBT modules are respectively described as a first IGBT module A 121 and a first IGBT module D 124, the two second IGBT modules are respectively described as a second IGBT module B 122 and a second IGBT module E 125, and the two third IGBT modules are respectively described as a third IGBT module C 123 and a third IGBT module F 126.

[0037] like Figure 3 As shown, the first IGBT module A 121 and the first IGBT module D 124 are connected in parallel with each other, the second IGBT module B 122 and the second IGBT module E 125 are connected in parallel with each other, and the third IGBT module C 123 and the third IGBT module F 126 are connected in parallel with each other. In addition, although Figure 3 , but the capacitor represents an absorption capacitor (such as a capacitor tank) separated from the power module. In the power module 100 according to the present embodiment, the absorption capacitor is not included.

[0038] The first IGBT module A 121 may include two IGBTs connected in series with each other, the two IGBTs being connected by a transistor T11 and a diode D11, and a transistor T51 and a diode D51, respectively. The second IGBT module B 122 may include two IGBTs connected in series with each other, the two IGBTs being connected by a transistor T21 and a diode D21, and a transistor T31 and a diode D31, respectively. The third IGBT module C 123 may include two IGBTs connected in series with each other, the two IGBTs being connected by a transistor T41 and a diode D4, and a transistor T61 and a diode D61, respectively.

[0039] The first IGBT module D 124 may include two IGBTs connected in series with each other, the two IGBTs are connected by a transistor T12 and a diode D12, and a transistor T52 and a diode D52, respectively. The second IGBT module E 125 may include two IGBTs connected in series with each other, the two IGBTs are connected by a transistor T22 and a diode D22, and a transistor T32 and a diode D32, respectively. The third IGBT module F 126 may include two IGBTs connected in series with each other, the two IGBTs are connected by a transistor T42 and a diode D42, and a transistor T62 and a diode D2, respectively.

[0040] like Figure 4 As shown, the first IGBT module A 121 to the third IGBT module C 123 and the first IGBT module D 124 to the third IGBT module F 126 can be arranged on the first heat dissipation surface of the heat sink 110 in sequence from left to right (i.e., in the order of IGBT module A to IGBT module F), and the coolant flowing in from the liquid inlet 111 of the heat sink 110 dissipates heat for the first IGBT module A 121 to the third IGBT module C 123 and the first IGBT module D 124 to the third IGBT module F 126, and then flows out from the liquid outlet 112 of the heat sink 110.

[0041] In addition, in this embodiment, the power module 100 may further include a first adapter board 150, a first circuit board 160, a first laminated DC busbar 170, and a first AC busbar 180. Although not shown, the power module 100 may further include other types of devices (such as resistors).

[0042] like Figure 2 As shown, the first adapter board 150 may be mounted on the first IGBT unit 120 and may be configured to drive the first IGBT unit 120. For example, the first adapter board 150 may be mounted on the first IGBT unit 120 using fasteners (such as bolts), but is not limited thereto. The first circuit board 160 may be disposed on the first adapter board 150 and may be connected to the first adapter board 150. For example, the first adapter board 150 may be connected to the first circuit board 160 via a wire.

[0043] like Figure 2 and Figure 4 As shown, the first laminated DC busbar 170 may include a laminated neutral busbar (or referred to as a zero busbar) 171 , a positive busbar 172 , and a negative busbar 173 , and may be disposed on a first side of the first IGBT unit 120 .

[0044] Specifically, one end of the first stacked DC busbar 170 may be connected to a terminal of the first IGBT unit (eg, screwed), and the other end of the first stacked DC busbar 170 may be connected to a conductive busbar of an external absorption capacitor (not shown).

[0045] One end of the neutral busbar 171 may be provided with a neutral connection terminal (not shown), one end of the positive busbar 172 may be provided with a positive connection terminal (not shown), and one end of the negative busbar 173 may be provided with a negative connection terminal (not shown).

[0046] Reference Figure 3 , the first connection terminal of the first IGBT module A 121 may be connected to the positive busbar 172 (e.g., the positive connection terminal), and the second connection terminal of the first IGBT module A 121 may be connected to the neutral busbar 171 (e.g., the neutral connection terminal). The first connection terminal of the third IGBT module C 123 may be connected to the neutral busbar 171 (e.g., the neutral connection terminal), and the second connection terminal of the third IGBT module C 123 may be connected to the negative busbar 173 (e.g., the negative connection terminal). The first connection terminal of the second IGBT module 122 may be connected to a node between two IGBTs of the first IGBT module (i.e., a connection node of transistor T11 and transistor T51), and the second connection terminal of the second IGBT module B 122 may be connected to a node between two IGBTs of the third IGBT module C 123 (i.e., a connection node of transistor T61 and transistor T41). In addition, the connection relationship between the first IGBT module D 124 , the second IGBT module E 125 , and the third IGBT module F 126 is the same as the connection relationship between the first IGBT module A 121 , the second IGBT module B 122 , and the third IGBT module C 123 .

[0047] In addition, when the power module 100 is mounted on a three-level converter (not shown), the other ends of the neutral busbar 171, the positive busbar 172, and the negative busbar 173 may be connected to the conductive bar (such as a copper bar, etc.) of the capacitor tank of the three-level converter. For example, the other end of the neutral busbar 171 may be provided with a neutral mounting hole 171h, the other end of the positive busbar 172 may be provided with a positive mounting hole 172h, and the other end of the negative busbar 173 may be provided with a negative mounting hole 173h. The neutral busbar 171, the positive busbar 172, and the negative busbar 173 may be connected to the conductive bar of the three-level converter through the neutral mounting hole 171h, the positive mounting hole 172h, and the negative mounting hole 173h.

[0048] A node between the two IGBTs of the second IGBT module B 122 (ie, a connection node between the transistor T21 and the transistor T31 ) may be connected to the first AC busbar 180 (to be described in detail later).

[0049] like Figure 2 As shown, the first AC busbar 180 may be disposed on a second side of the first IGBT unit 120 opposite to the first side. One end of the first AC busbar 180 may be connected to the IGBT module through a connector. Specifically, as described above, one end of the first AC busbar 180 may be connected to a node between two IGBTs of the second IGBT module B 122 (i.e., a connection node between transistors T21 and T31). As an example, the first AC busbar 180 may be formed using a material having excellent electrical conductivity (such as copper).

[0050] In addition, when the power module 100 is mounted on a three-level converter, the other end of the first AC busbar 180 can be connected to an AC conductive bar (such as a copper bar) of the three-level converter. For example, an AC mounting hole 180h can be provided at the other end of the first AC busbar 180, so that the connection with the AC conductive bar of the three-level converter can be achieved through the AC mounting hole 180h.

[0051] As described above, in this embodiment, by using three IGBT groups consisting of IGBT modules connected in parallel, the output power of the power module can be increased under the same external dimensions. In addition, when the power module according to this embodiment is applied to a three-level converter, the power of the three-level converter can be increased.

[0052] In addition, as described above, each IGBT module is packaged based on PrimePACKTM3 or a similar method, so each IGBT module has a strong current carrying capacity and excellent mechanical strength and vibration resistance. Therefore, the power module according to this embodiment can increase the output power at the same size and have excellent reliability. In addition, when the power module according to this embodiment is applied to a three-level converter, the failure rate of the three-level converter to which the power module according to this embodiment is applied can be reduced, so that the three-level converter can operate stably for a long time.

[0053] In addition, although the surface of the heat dissipation plate 110 opposite to the first heat dissipation surface is not shown, the heat dissipation plate 110 may have a second heat dissipation surface opposite to the first heat dissipation surface. The power module 100 may further include a second IGBT unit, that is, the power module 100 may include a first IGBT unit 120 and a second IGBT unit.

[0054] The second IGBT unit may be disposed on the second heat dissipation surface of the heat dissipation plate 110 and have a symmetrical structure based on the heat dissipation plate 110 and the first IGBT unit 120. That is, the first IGBT unit 120 and the second IGBT unit are disposed on the first heat dissipation surface and the second heat dissipation surface of the heat dissipation plate 110, respectively (i.e., Figure 2On the left and right sides of the heat sink 110 in the figure), and are mirror images of each other relative to the center of the heat sink 110.

[0055] Therefore, in this embodiment, the heat sink 110 can dissipate heat for the IGBT modules disposed on two surfaces of the heat sink 110 , thereby improving the heat dissipation efficiency of the power module 100 and ensuring stable operation of the power module 100 .

[0056] Accordingly, although not shown, the power module 100 may also include a second adapter board, a second circuit board, a second stacked DC busbar and a second AC busbar, and the second adapter board, the second circuit board, the second stacked DC busbar and the second AC busbar are symmetrically arranged and installed with the first adapter board 150, the first circuit board 160, the first stacked DC busbar 170 and the first AC busbar 180 about the heat sink 110.

[0057] That is, the power module 100 can be designed as a left-right mirror structure with the heat sink 110 as the center (eg Figure 2 shown).

[0058] Return to reference Figure 1 The power module 100 may further include a housing 140. The first IGBT unit 120 and its related components may be disposed in the housing 140. When the power module 100 has a mirror structure as described above, the first IGBT unit 120 and the second IGBT unit and their respective related components may be disposed in the housing 140.

[0059] The housing 140 may include a top plate 143 and a base 144 and side plates connected via the top plate 143 and the base 144. As an example, the housing 140 may include a first side plate 141 and a second side plate 142 that are opposite to each other. Figure 1 As shown, the top plate 143 and the base 144 may have a plurality of through holes, respectively. Therefore, when the IGBT unit, the adapter board, the circuit board and other devices are installed in the housing, the heat dissipation efficiency of the devices arranged in the housing 140 can be improved. In addition, the first side plate 141 and the second side plate 142 may be connected to each other to protect the devices arranged in the housing 140 from external impact. As an example, the housing 140 may be formed using a metal material, but is not limited thereto.

[0060] As described above, the power module for the three-level converter according to the present invention uses three IGBT groups formed by IGBT modules connected in parallel, and the IGBT modules are arranged in a straight line, so the output power can be increased with the same external dimensions.

[0061] In addition, the power module for a three-level converter according to the utility model sets the IGBT modules symmetrically with respect to the heat sink, so that more IGBT modules can be arranged to achieve structural optimization, further improving the output power and making the power module have excellent reliability.

[0062] The utility model also provides a three-level converter. The three-level converter may include a power module 100 according to the above embodiment. The power module 100 may cooperate with the upper rail of the three-level converter with a base 144 and a heat sink 110 as a supporting structure, and the power module 100 may be installed in the three-level converter in a push-in manner. In addition, the three-level converter may further include an absorption capacitor, and the AC side of the power module may be connected to the absorption capacitor.

[0063] The beneficial effects of the three-level converter can be found in the beneficial effects of the power module in the above embodiment, which will not be described in detail here.

[0064] The above describes the specific implementation methods of the present invention in detail. Although some embodiments have been shown and described, those skilled in the art should understand that these embodiments can be combined, modified and improved without departing from the principle and spirit of the present invention whose scope is defined by the claims (for example, different technical features of the present invention can be combined to obtain new technical solutions). These combinations, modifications and improvements should also be within the scope of protection of the present invention.

Claims

1. A power module for a three-level converter, characterized in that: The power module (100) comprises: A heat dissipation plate (110) having a first heat dissipation surface; A first IGBT unit (120) is arranged on the heat sink (110) and comprises a first IGBT group, a second IGBT group and a third IGBT group, wherein the first IGBT group comprises two or more first IGBT modules connected in parallel to each other, the second IGBT group comprises two or more second IGBT modules connected in parallel to each other, and the third IGBT group comprises two or more third IGBT modules connected in parallel to each other, wherein each of the two or more first IGBT modules, the two or more second IGBT modules, and the two or more third IGBT modules includes two IGBTs connected in series with each other, and The two or more first IGBT modules, the two or more second IGBT modules and the two or more third IGBT modules are arranged in a straight line on the first heat dissipation surface along the length direction of the heat dissipation plate (110).

2. The power module for a three-level converter according to claim 1, characterized in that: The heat sink (110) has a liquid inlet (111) and a liquid outlet (112), so that the coolant flowing in through the liquid inlet (111) dissipates heat for a first IGBT unit (120) arranged on the heat sink (110) and then flows out from the liquid outlet (112).

3. The power module (100) for a three-level converter according to claim 1, characterized in that: The power module (100) further comprises a first stacked DC busbar (170), the first stacked DC busbar (170) comprising a stacked neutral busbar (171), a positive busbar (172) and a negative busbar (173), and is arranged on a first side of the first IGBT unit (120).

4. The power module (100) for a three-level converter according to claim 3, characterized in that: The first connection terminals of the two or more first IGBT modules are connected to the positive busbar (172), and the second connection terminals of the two or more first IGBT modules are connected to the neutral busbar (171). The first connection terminals of the two or more third IGBT modules are connected to the neutral busbar (171), and the second connection terminals of the two or more third IGBT modules are connected to the negative busbar (173). The first connection terminals of the two or more second IGBT modules are connected to a node between two IGBTs of each of the two or more first IGBT modules, and the second connection terminals of the two or more second IGBT modules are connected to a node between two IGBTs of each of the two or more third IGBT modules.

5. The power module for a three-level converter according to claim 4, characterized in that: The power module (100) further comprises a first AC busbar (180), wherein the first AC busbar (180) is arranged on a second side of the first IGBT unit (120) opposite to the first side. Wherein, a node between two IGBTs of each of the two or more second IGBT modules is connected to the first AC busbar (180).

6. The power module for a three-level converter according to claim 5, characterized in that: The power module (100) further comprises: A first adapter board (150), disposed on the first IGBT unit (120) and configured to drive the first IGBT unit (120); A first circuit board (160) is arranged on the first adapter board (150).

7. The power module for a three-level converter according to claim 6, characterized in that: The power module (100) further includes a second IGBT unit, which is arranged on a second heat dissipation surface of the heat dissipation plate (110) opposite to the first heat dissipation surface and has a structure symmetrical with the first IGBT unit (120) based on the heat dissipation plate (110).

8. The power module for a three-level converter according to claim 7, characterized in that: The power module (100) further comprises a second adapter board, a second circuit board, a second laminated DC busbar and a second AC busbar, wherein the second adapter board, the second circuit board, the second laminated DC busbar and the second AC busbar are symmetrically arranged with the first adapter board (150), the first circuit board (160), the first laminated DC busbar (170) and the first AC busbar (180) with respect to the heat sink (110).

9. The power module (100) for a three-level converter according to claim 7 or 8, characterized in that: The power module (100) further comprises a housing (140), the housing (140) comprising a base (144), a top plate (143), and a side plate connected via the base (144) and the top plate (143), the top plate (143) and the base (144) respectively having a plurality of through holes, The first IGBT unit (120) and the second IGBT unit are installed in the housing (140).

10. A three-level converter, characterized in that: The three-level converter comprises the power module according to any one of claims 1 to 9 and an absorption capacitor, wherein an AC side of the power module is connected to the absorption capacitor.

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