Power unit and converter device

Abstract

The utility model discloses a power unit and a converter device, the power unit comprises an AC module, a power module and an auxiliary capacitor module, the power module is connected with the AC module, the power module comprises an IGBT module and a first capacitor pool which are electrically connected with each other, and the auxiliary capacitor module is electrically connected with the first capacitor pool. The total capacitance value of the first capacitor pool is smaller than the total capacitance value of the auxiliary capacitor module. According to the technical scheme, stray inductance can be reduced, the voltage peak is prevented from being too high, and the voltage stabilizing function is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of converter devices, and in particular to a power unit and a converter device. Background Art

[0002] In energy storage systems, the converter is an essential component. In related technologies, the stray inductance of power modules can affect their power conversion efficiency. Due to low switching frequencies and large DC ripples, a large number of capacitors is required. However, this large number of capacitors results in a high total capacitance value in the power module, resulting in high stray inductance, which can cause high voltage spikes and affect voltage stability. Utility Model Content

[0003] The embodiments of the present application provide a power unit and a current conversion device, which can help reduce stray inductance, avoid excessive voltage spikes, and perform a voltage stabilization function.

[0004] In a first aspect, an embodiment of the present application provides a power unit, comprising: an AC module, a power module, and an auxiliary capacitor module. The power module is connected to the AC module, the power module comprises an insulated-gate bipolar transistor (IGBT) module and a first capacitor pool electrically connected to each other, the auxiliary capacitor module is electrically connected to the first capacitor pool, and the total capacitance of the first capacitor pool is less than the total capacitance of the auxiliary capacitor module.

[0005] The embodiment of the present application forms a commutation circuit and reduces stray inductance by electrically connecting the insulated gate bipolar transistor (IGBT) module in the power module to the first capacitor pool. Because the first capacitor pool is insufficient to provide sufficient energy to suppress DC ripple, an auxiliary capacitor module is provided in the power unit and electrically connected to the first capacitor pool. The total capacitance of the first capacitor pool is less than the total capacitance of the auxiliary capacitor module. The auxiliary capacitor module serves as a supplementary carrier for the energy output of the first capacitor pool, which helps prevent excessive voltage spikes and provides a voltage stabilization function.

[0006] According to the aforementioned embodiments of the first aspect of the present application, the power module further includes a first support plate, and the IGBT module, the first capacitor pool, and the AC module are integrally mounted on the first support plate. In these embodiments, by integrally mounting the power module and the AC module on the first support plate, the tight integration and modular design between the power module and the AC module provide advantages in installation, maintenance, and performance optimization of the entire power unit.

[0007] According to the aforementioned embodiment of the first aspect of the present application, the power module further includes a plurality of support columns, which are supported and arranged between the IGBT module and the first support plate, so that the IGBT module and the first support plate are separated to form an accommodation space, and the AC module is arranged in the accommodation space.

[0008] According to the aforementioned embodiment of the first aspect of the present application, the IGBT module includes a heat sink and multiple IGBT sub-modules, the multiple IGBT sub-modules are arranged on the heat sink, and the multiple support columns are supported and arranged between the heat sink and the first support plate.

[0009] According to the aforementioned embodiment of the first aspect of the present application, the IGBT module includes multiple IGBT sub-modules, the first capacitor pool includes a first capacitor and a first busbar, the first busbar and the first capacitor are electrically connected, and the first busbar and the multiple IGBT sub-modules are overlapped on the same plane. In the above embodiment, by overlapping the multiple IGBT sub-modules and the first capacitor on the same plane, the multiple IGBT sub-modules are connected to the first busbar in a straight line, which is conducive to reducing the distance between the multiple IGBT sub-modules and the first busbar, and is conducive to reducing the current loop path and area. The number of capacitors in the first capacitor pool is minimized, and the length of the first busbar is shortened as much as possible, which is conducive to reducing the power module inductance and reducing voltage spikes.

[0010] According to the aforementioned embodiment of the first aspect of the present application, the first busbar includes a first busbar body and a first electrical connection portion. The first busbar body is connected to one end of the first capacitor. The first electrical connection portion extends outward from one side edge of the first busbar body and overlaps with multiple IGBT sub-modules.

[0011] According to the aforementioned embodiment of the first aspect of the present application, the first capacitor pool includes a first capacitor and a first busbar, the first busbar and the first capacitor are electrically connected, the auxiliary capacitor module includes multiple second capacitors and a second busbar, the second busbar and the second capacitor are electrically connected, and the second busbar is electrically connected to the first busbar.

[0012] According to the aforementioned embodiment of the first aspect of the present application, the second busbar includes a second busbar body and a second electrical connection portion, the second busbar body is connected to one end of a plurality of second capacitors, and the second electrical connection portion extends outward from a side edge of the second busbar body and is electrically connected to the first busbar.

[0013] According to the aforementioned implementation of the first aspect of the present application, the length of the first busbar is smaller than the length of the second busbar.

[0014] According to the aforementioned implementation of the first aspect of the present application, the power unit further includes: the number of capacitors of the first capacitor is smaller than the number of capacitors of the second capacitor, and / or the capacitance of the first capacitor is smaller than the capacitance of the second capacitor.

[0015] According to the aforementioned embodiment of the first aspect of the present application, the second electrical connection portion includes a connection hole, and the second busbar and the first busbar are connected through the connection hole.

[0016] In a second aspect, an embodiment of the present application provides a converter device, which includes a power unit according to any of the aforementioned embodiments of the first aspect of the present application.

[0017] In the embodiment of the present application, a power unit is provided in the converter device, and the IGBT module in the power module is electrically connected to the first capacitor pool in the power unit, thereby forming a commutation circuit and reducing noise inductance. Because the first capacitor pool module is insufficient to provide sufficient energy to suppress DC ripple, an auxiliary capacitor module is provided in the power unit and electrically connected to the first capacitor pool. The total capacitance of the first capacitor pool is less than the total capacitance of the auxiliary capacitor module. The auxiliary capacitor module serves as a supplementary carrier for the energy output of the first capacitor pool, which helps to avoid excessive voltage spikes and can provide a voltage stabilization function. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of an embodiment of a power unit of the present application;

[0019] Figure 2 A schematic diagram of an AC module and a power module of an embodiment of a power unit of the present application;

[0020] Figure 3 This is a schematic diagram of the auxiliary capacitor module structure of an embodiment of the power unit of the present application;

[0021] Figure 4 This is a circuit schematic diagram of a power module and an auxiliary capacitor module according to an embodiment of the power unit of the present application.

[0022] Description of Figure Numbers:

[0023] AC module-100, power module-200, auxiliary capacitor module-300, DC module-400;

[0024] IGBT module 210, first capacitor pool 220, first support plate 230, support column 240, second capacitor 310, second busbar 320, second support plate 330;

[0025] Heat sink 211, IGBT submodule 212, first capacitor 221, first busbar 222, second busbar body 321, second electrical connection portion 322;

[0026] First busbar body 2221, first electrical connection portion 2222, third electrical connection portion 2223, connection hole 3221;

[0027] Accommodating space-R1, first capacitor pool inductor-L1, auxiliary capacitor module inductor-L2, first capacitor pool capacitor-C1, auxiliary capacitor module capacitor-C2. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0029] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0031] This embodiment provides a power unit and a current conversion device, which can help reduce the current loop area, lower the noise inductance, avoid excessive voltage spikes, and perform a voltage stabilization function.

[0032] like Figure 1 As shown, an embodiment of the present application provides a power unit, which includes: an AC module 100, a power module 200, and an auxiliary capacitor module 300. The power module 200 is connected to the AC module 100, and the power module 200 includes an insulated-gate bipolar transistor (IGBT) module 210 and a first capacitor pool 220 electrically connected to each other. The auxiliary capacitor module 300 is electrically connected to the first capacitor pool 220, and the total capacitance value of the first capacitor pool 220 is less than the total capacitance value of the auxiliary capacitor module 300.

[0033] The embodiment of the present application electrically connects the insulated gate bipolar transistor (IGBT) module 210 in the power module 200 to the first capacitor pool 220 to form a commutation circuit and reduce stray inductance. Because the first capacitor pool 220 module is insufficient to provide sufficient energy to suppress DC ripple, an auxiliary capacitor module 300 is provided in the power unit and electrically connected to the first capacitor pool 220. The total capacitance of the first capacitor pool 220 is less than the total capacitance of the auxiliary capacitor module 300. The auxiliary capacitor module 300 serves as a supplementary carrier for the energy output of the first capacitor pool 220, which helps prevent excessive voltage spikes and can provide a voltage stabilization function.

[0034] like Figure 2 As shown, the power module 200 further includes a first support plate 230, and the IGBT module 210, the first capacitor pool 220, and the AC module 100 are integrally mounted on the first support plate 230. In the above embodiment, by integrally mounting the power module 200 and the AC module on the first support plate 230, the tight integration and modular design between the power module 200 and the AC module 100 provide advantages in installation, maintenance, and performance optimization of the entire power unit.

[0035] like Figure 2 As shown, the power module 200 further includes a plurality of support columns 240 , which are supported and arranged between the IGBT module 210 and the first support plate 230 , so that the IGBT module 210 and the first support plate 230 are spaced apart to form an accommodation space R1 , and the AC module 100 is arranged in the accommodation space R1 .

[0036] like Figures 1 to 2 As shown, the IGBT module 210 includes a heat sink 211 and a plurality of IGBT sub-modules 212 . The plurality of IGBT sub-modules 212 are disposed on the heat sink 211 , and a plurality of support columns 240 are supported and disposed between the heat sink 211 and the first support plate 230 .

[0037] like Figures 1 to 2As shown, the IGBT module 210 includes multiple IGBT sub-modules 212, and the first capacitor pool 220 includes a first capacitor 221 and a first busbar 222. The first busbar 222 and the first capacitor 221 are electrically connected, and the first busbar 222 and the multiple IGBT sub-modules 212 are overlapped on the same plane. By overlapping the multiple IGBT sub-modules 212 and the first capacitor 221 on the same plane, the multiple IGBT sub-modules 212 are connected to the first busbar 222 in a straight line, which helps to reduce the distance between the multiple IGBT sub-modules 212 and the first busbar 222, and helps to reduce the current loop path and area. The number of capacitors in the first capacitor pool 220 is minimized, and the length of the first busbar 222 is minimized, which helps to reduce the inductance of the power module 200 and reduce voltage spikes. In one embodiment, the first busbar 222 supports at least one first capacitor 221, and the total capacitance value of the auxiliary capacitor module 300 is greater than the total capacitance value of the first capacitor 221.

[0038] like Figure 2 As shown, the first busbar 222 includes a first busbar body 2221 and a first electrical connection portion 2222. The first busbar body 2221 is connected to one end of the first capacitor 221. The first electrical connection portion 2222 extends outward from one side edge of the first busbar body 2221 and overlaps with multiple IGBT sub-modules 212.

[0039] like Figure 1 As shown, the first capacitor pool 220 includes a first capacitor 221 and a first busbar 222, the first busbar 222 and the first capacitor 221 are electrically connected, the auxiliary capacitor module 300 includes a plurality of second capacitors 310 and a second busbar 320, the second busbar 320 and the second capacitor 310 are electrically connected, and the second busbar 320 and the first busbar 222 are electrically connected. Figures 1 to 3 As shown, the length of the first busbar 222 is shorter than that of the second busbar 320 , which is beneficial to reducing the stray inductance of the power module 200 and lowering voltage spikes.

[0040] It is understood that the total capacitance value of the first capacitor pool 220 is less than the total capacitance value of the auxiliary capacitor module 300. Therefore, in one embodiment, the number of capacitors of the first capacitor 221 can be set to be less than the number of capacitors of the second capacitor 310. In other embodiments, the capacitance of the first capacitor 221 can also be set to be less than the capacitance of the second capacitor 310. It is also possible to set the number of capacitors and the capacitance of the first capacitor 221 to be less than the number of capacitors and the capacitance of the second capacitor 310.

[0041] It should be noted that the total capacitance value of the auxiliary capacitor module 300 is at least twice the total capacitance value of the first capacitor pool 220 , which is beneficial for avoiding excessive voltage spikes and can play a voltage stabilization function.

[0042] like Figure 3As shown, the second busbar 320 includes a second busbar body 321 and a second electrical connection portion 322. The second busbar body 321 is connected to one end of multiple second capacitors 310. The second electrical connection portion 322 extends outward from a side edge of the second busbar body 321 and is electrically connected to the first busbar 222.

[0043] like Figure 4 As shown, since the auxiliary capacitor module 300 is electrically connected to the first capacitor pool 220, and the total capacitance value of the first capacitor pool 220 is smaller than the total capacitance value of the auxiliary capacitor module 300, when the impedance of the first capacitor pool 220 is much smaller than the impedance value of the auxiliary capacitor module 300, that is, in the following situation:

[0044] ZZL222ZZL1C1+ZL1

[0045] Wherein, L1 is the inductance of the first capacitor pool 220, L2 is the inductance of the auxiliary capacitor module 300, C1 is the capacitance of the first capacitor pool 220, C2 is the capacitance of the auxiliary capacitor module 300, Z1 is the impedance of the first capacitor pool 220, and Z2 is the impedance of the auxiliary capacitor module 300;

[0046] At this time, the circuit is in a conducting state, and the energy of the auxiliary capacitor module 300 is transmitted to the first capacitor pool 220 to suppress the DC ripple and stabilize the voltage.

[0047] like Figure 2 As shown, the first busbar 222 further includes a third electrical connection portion 2223, which extends outward from the other side edge of the first busbar body 2221, and the second electrical connection portion 322 is electrically connected to the third electrical connection portion 2223. Figure 3 As shown, the second electrical connection portion 322 includes a connection hole, into which a connector can be inserted, and the second electrical connection portion 322 is connected to the third electrical connection portion 2223 by disposing a connector in the connection hole. The auxiliary capacitor module 300 also includes a second support plate 330, and the second capacitor 310 is mounted on the second support plate 330.

[0048] like Figure 1 As shown, the power unit further includes: a DC module 400 , which is electrically connected to the power module 200 .

[0049] The present application also provides a converter device, which includes a power unit according to any of the above embodiments. Figure 1As shown, the power unit includes: an AC module 100, a power module 200, and an auxiliary capacitor module 300. The power module 200 is connected to the AC module 100. The power module 200 includes an IGBT module 210 and a first capacitor pool 220 that are electrically connected to each other. The auxiliary capacitor module 300 is electrically connected to the first capacitor pool 220. The total capacitance of the first capacitor pool 220 is less than the total capacitance of the auxiliary capacitor module 300.

[0050] In the embodiment of the present application, a power unit is provided in the converter device. In the power unit, the IGBT module 210 in the power module 200 is electrically connected to the first capacitor pool 220, thereby forming a commutation circuit and reducing noise inductance. Because the first capacitor pool 220 module is insufficient to provide sufficient energy to suppress DC ripple, an auxiliary capacitor module 300 is provided in the power unit and electrically connected to the first capacitor pool 220. The total capacitance of the first capacitor pool 220 is less than the total capacitance of the auxiliary capacitor module 300. The auxiliary capacitor module 300 serves as a supplementary carrier for the energy output of the first capacitor pool 220, which helps to avoid excessive voltage spikes and can provide a voltage stabilization function.

[0051] The above description is only a preferred embodiment of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made by using the contents of the present application description and drawings under the inventive concept of the present application, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A power unit, characterized in that: The power unit includes: AC module; a power module, the power module being connected to the AC module, the power module comprising an IGBT module and a first capacitor pool electrically connected to each other; and An auxiliary capacitor module is electrically connected to the first capacitor pool, and the total capacitance value of the first capacitor pool is smaller than the total capacitance value of the auxiliary capacitor module.

2. The power unit according to claim 1, wherein: The power module further includes a first support plate, and the IGBT module, the first capacitor pool, and the AC module are integrally mounted on the first support plate.

3. The power unit according to claim 2, wherein: The power module further includes a plurality of support columns, which are supported and arranged between the IGBT module and the first support plate, so that the IGBT module and the first support plate are spaced apart to form an accommodation space, and the AC module is arranged in the accommodation space.

4. The power unit according to claim 3, wherein: The IGBT module includes a heat sink and a plurality of IGBT sub-modules. The plurality of IGBT sub-modules are arranged on the heat sink, and the plurality of support columns are supported and arranged between the heat sink and the first support plate.

5. The power unit according to claim 1, wherein: The IGBT module includes multiple IGBT sub-modules, the first capacitor pool includes a first capacitor and a first busbar, the first busbar is electrically connected to the first capacitor, and the first busbar and the multiple IGBT sub-modules are overlapped on the same plane.

6. The power unit according to claim 5, wherein: The first busbar includes a first busbar body and a first electrical connection portion. The first busbar body is connected to one end of the first capacitor. The first electrical connection portion extends outward from a side edge of the first busbar body and overlaps with the multiple IGBT sub-modules.

7. The power unit according to claim 1, wherein: The first capacitor pool includes a first capacitor and a first busbar, the first busbar is electrically connected to the first capacitor, the auxiliary capacitor module includes multiple second capacitors and a second busbar, the second busbar is electrically connected to the second capacitor, and the second busbar is electrically connected to the first busbar.

8. The power unit according to claim 7, wherein: The second busbar includes a second busbar body and a second electrical connection portion. The second busbar body is connected to one end of the plurality of second capacitors. The second electrical connection portion extends outward from a side edge of the second busbar body and is electrically connected to the first busbar.

9. The power unit according to claim 8, wherein: The first busbar length is smaller than the second busbar length.

10. The power unit according to claim 8, wherein: The capacitance of the first capacitor is smaller than the capacitance of the second capacitor; and / or The capacitance of the first capacitor is smaller than the capacitance of the second capacitor.

11. The power unit according to claim 8, wherein: The second electrical connection portion includes a connection hole, and the second busbar is connected to the first busbar through the connection hole.

12. A current conversion device, characterized in that: The converter device comprises the power unit according to any one of claims 1 to 11.

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