Capacitor module and power converter

Abstract

The present application relates to the technical field of capacitors, and particularly relates to a capacitor module and a power converter. The capacitor module comprises a housing and a capacitor core pack assembly, wherein the housing comprises an accommodating cavity having an opening at one end, and the accommodating cavity is used for accommodating the capacitor core pack assembly; and the capacitor core pack assembly comprises a plurality of capacitor core packs, there is a gap between every two adjacent capacitor core packs, a cathode foil comprised in each capacitor core pack is partially exposed from the surface of the capacitor core pack, the exposed portion of the cathode foil is located at the end of the capacitor core pack that is away from the opening of the housing, and the exposed portion of the cathode foil is in contact with the housing, so as to transfer to the housing heat generated by the capacitor core pack. In the capacitor module of the present application, a plurality of capacitor core packs are integrated into one accommodating cavity, thereby reducing the volume of the capacitor module.

Description

Capacitor module and power converter

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on September 15, 2023, with application number 202311199782.1 and application name "A capacitor module and power converter", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of capacitor technology, and in particular to a capacitor module and a power converter. Background Art

[0004] Capacitors are passive energy storage devices that are commonly used in circuits for filtering, coupling, DC isolation, and bypassing. Capacitors are usually discrete structures. Users combine discrete capacitors in series and parallel to meet product specifications such as voltage, capacity, correction frequency, and ripple current.

[0005] In the prior art, a capacitor module is assembled from discrete capacitors. The discrete capacitors include a core package and a metal shell. The capacitor core packages in two adjacent discrete capacitors are separated by a metal shell and a gap, resulting in a larger volume of the capacitor module.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a capacitor module and a power converter. The capacitor module integrates multiple capacitor core packages into a housing cavity, thereby reducing the volume of the capacitor module.

[0008] In the first aspect, a capacitor module is provided, which includes a shell and a capacitor core package assembly, wherein the shell includes a receiving cavity with an opening at one end, and the receiving cavity receives the capacitor core package assembly. The capacitor core package assembly includes a plurality of capacitor core packages, and there is a gap between each two adjacent capacitor core packages. The capacitor core package includes a cathode foil, and the cathode foil is partially exposed at the end of the capacitor core package away from the opening. The exposed portion of the cathode foil is in contact with the shell to transfer the heat generated by the capacitor core package to the shell. In the present application, the cathode foil included in the capacitor core package is in direct contact with the shell, which can improve the heat generated by the capacitor core package and dissipate it quickly through the shell, thereby improving the heat dissipation efficiency of the capacitor core package, and further improving the heat dissipation efficiency of the capacitor module, so as to increase the service life of the capacitor module. In addition, in the present application, the capacitor module integrates multiple capacitor core packages into a receiving cavity, which can save the space occupied by the aluminum plate, thereby reducing the volume of the capacitor module.

[0009] The capacitor core package may be in a cylindrical or rectangular shape. When the capacitor core package is rectangular, the capacitor core package is prepared by a winding or lamination process.

[0010] In one embodiment, the capacitor core package further includes an anode foil and a stop-roll belt, and the stop-roll belt is located on the outer peripheral side of the capacitor core package. The cathode foil is located between the anode foil and the stop-roll belt, and along the first direction, the length of the stop-roll belt is less than the length of the cathode foil. To ensure that the cathode foil portion can be exposed to the outside of the capacitor core package. Alternatively, the anode foil is located between the cathode foil and the stop-roll belt, and along the first direction, the length of the cathode foil is greater than the length of the stop-roll belt and the anode foil. It can also ensure that the cathode foil is exposed to the outside of the capacitor core package and contacts the shell to dissipate heat from the capacitor core package. It is worth mentioning that the first direction is a direction perpendicular to the bottom wall of the shell.

[0011] In one embodiment, the capacitor module further includes a positioning plate, which includes multiple positioning portions, with a gap between two adjacent positioning portions, and each positioning portion fixes a capacitor core pack. In this manner, the multiple positioning portions are used to fix multiple capacitor core packs so that a gap exists between two adjacent capacitor core packs. The multiple capacitor core packs can be prefabricated on the positioning plate, thereby improving the convenience of capacitor module assembly.

[0012] It is worth mentioning that the positioning plate can be prepared from an insulating pad.

[0013] In one embodiment, the capacitor module further includes a plurality of support columns arranged in an array, and the plurality of support columns are fixed to the bottom wall of the housing. Each capacitor core package includes a central hole, and along a first direction, the central hole passes through the capacitor core package, and the axis of the central hole coincides with the center line of the capacitor core package. The plurality of support columns are distributed and penetrate the central holes of the plurality of capacitor core packages. The plurality of capacitor core packages are fixed in the housing by the plurality of support columns, thereby improving the convenience of installing the capacitor core packages in the housing. The first direction is a direction perpendicular to the bottom wall of the housing.

[0014] In one embodiment, when the capacitor core package is fixed in the shell by support columns, along the first direction, the length of the multiple support columns is less than the height of the center holes of the multiple capacitor core packages. Or along the first direction, the length of the multiple support columns is greater than the height of the center holes of the multiple capacitor core packages. When the length of the multiple support columns is greater than the height of the center holes of the multiple capacitor core packages, in order to improve the stability of the capacitor core package installed in the shell, the capacitor module also includes a pressure plate, the pressure plate includes multiple fixing holes, and there is a gap between two adjacent fixing holes. The pressure plate covers the end of the capacitor core package assembly facing the opening, and the ends of the multiple support columns away from the bottom wall are respectively fixedly connected to the multiple fixing holes. To limit the movement of the capacitor core package along the first direction.

[0015] In one embodiment, in order to connect the anode foil strips of multiple capacitor core packs in series and parallel, and the cathode foil strips of multiple capacitor core packs in series and parallel, the capacitor core pack assembly further includes a positive bus and a negative bus, the positive bus is connected to the anode foil strips of the multiple capacitor core packs, and the negative bus is connected to the cathode foil strips of the multiple capacitor core packs, wherein the positive bus and the negative bus are located at one end of the capacitor core pack assembly facing the opening. It is worth mentioning that the anode foil strip can be understood as a positive electrode tab, and the cathode foil strip can be understood as a negative electrode tab.

[0016] In one embodiment, to improve the safety of the capacitor core pack, the anode foil strip includes a fuse. Alternatively, the positive electrode busbar includes a fuse. Alternatively, the cathode foil strip includes a fuse. Alternatively, the negative electrode busbar includes a fuse.

[0017] In one embodiment, the anode foil strip includes a first opening as a fuse device. The first opening penetrates the anode foil strip along the thickness direction of the anode foil strip. The first opening is fused to ensure the safety of the capacitor core pack.

[0018] In one embodiment, the cathode foil strip includes a second opening as a fuse device, and the second opening penetrates the cathode foil strip along the thickness direction of the cathode foil strip. The second opening is fused to ensure the safety of the capacitor core pack.

[0019] In one embodiment, the fuse device included in the positive busbar is a third opening, which penetrates the positive busbar along the thickness direction of the positive busbar. The third opening is fused to ensure the safety of the capacitor core pack.

[0020] In one embodiment, the fuse device included in the negative electrode busbar is a fourth opening, which penetrates the negative electrode busbar along the thickness direction of the negative electrode busbar. The fourth opening is fused to ensure the safety of the capacitor core pack.

[0021] In one embodiment, the capacitor module further includes a packaging plate, which is fixedly connected to the opening of the housing. The packaging plate and the housing enclose a sealed installation cavity. It can be understood that the packaging plate seals the accommodating cavity to form an accommodating cavity. The packaging plate is used to seal multiple capacitor core packs, positive bus bars, and negative bus bars in the housing to improve the stability of the capacitor core packs.

[0022] In one embodiment, the positive busbar includes positive terminals, and the negative busbar includes negative terminals, both of which pass through the packaging board. This allows the current output end of the capacitor module to be located on one side of the packaging board. Alternatively, the positive terminals and negative terminals pass through the side wall of the housing, allowing the current output end of the capacitor module to be located on one side of the side wall of the housing.

[0023] In one embodiment, the capacitor module further includes an insulating layer, which is filled between the plurality of capacitor core packages and the packaging plate to ensure that the anode foil strips and the cathode foil strips are not electrically connected to the housing.

[0024] In one embodiment, the packaging board includes at least one pressure relief valve to prevent the capacitor module from exploding.

[0025] When there is one pressure relief valve, the pressure relief valve is arranged at the center of the packaging plate. When there are multiple pressure relief valves, the multiple pressure relief valves are arranged in an array, and along the first direction, each pressure relief valve corresponds to a capacitor core package.

[0026] In one embodiment, the capacitor module further includes a heat sink connected to the housing to dissipate heat from the housing. More specifically, the heat sink is positioned flush against the bottom wall of the housing. A thermally conductive insulating adhesive or thermally conductive silicone pad may be positioned between the heat sink and the capacitor module.

[0027] In a second aspect, a power converter is provided, comprising a power module and the capacitor module of any technical solution of the first aspect, the power module being electrically connected to the capacitor core assembly and disposed on a side of the capacitor module that is away from the bottom wall of the housing. In this embodiment, the capacitor module has a high heat dissipation efficiency, thereby improving the heat dissipation efficiency of the power converter including the capacitor module, thereby enhancing the operational stability of the power converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic structural diagram of a capacitor core package in a capacitor module provided in an embodiment of the present application;

[0029] FIG2 is a schematic structural diagram of a capacitor module provided in an embodiment of the present application;

[0030] FIG2a is a schematic structural diagram of a capacitor core package in this embodiment;

[0031] FIG2 b is another structural schematic diagram of the capacitor core package in this embodiment;

[0032] FIG3 is a schematic structural diagram of a capacitor core package assembly in a capacitor module provided in an embodiment of the present application;

[0033] FIG4 is a schematic structural diagram of a housing in a capacitor module provided in an embodiment of the present application;

[0034] FIG5 is a schematic structural diagram of a capacitor module provided in an embodiment of the present application;

[0035] FIG6 a is a schematic diagram of another structure of a capacitor core package in a capacitor module provided in an embodiment of the present application;

[0036] FIG6 b is a schematic structural diagram of a capacitor core package assembly in a capacitor module provided in an embodiment of the present application;

[0037] FIG7 is a schematic structural diagram of a heat sink in a capacitor module provided in an embodiment of the present application;

[0038] FIG8 is another structural diagram of a capacitor module provided in an embodiment of the present application.

[0039] Figure markings: 1-capacitor core package assembly; 10-capacitor core package; 10a-cathode foil; 10b-anode foil; 10c-anti-roll tape; 10d-electrolytic paper; 100-anode foil guide strip; 1000-first opening; 101-cathode foil guide strip; 1010-second opening; 102-exposed portion of cathode foil; 103-center hole; 11-positioning plate; 2-shell; 20-accommodating cavity; 21-support column; 22-connecting part; 23-lead-out hole; 3-pressing plate; 4-positive busbar; 40-positive terminal; 41-third opening; 5-negative busbar; 50-negative terminal; 51-fourth opening; 6-packaging plate; 60-pressure relief valve; 7-radiator. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of this application clearer, this application will be further described in detail below with reference to the accompanying drawings.

[0041] In the prior art, capacitor modules are widely used in fields such as electric vehicles and photovoltaics. Capacitor modules generally include multiple discrete capacitors, which are connected in series and parallel via a busbar and a circuit board. Each discrete capacitor requires an independent fixing device to fix the discrete capacitor. Each discrete capacitor also requires an independent isolation device to isolate two adjacent discrete capacitors, which results in a capacitor module composed of multiple discrete capacitors being relatively large. In addition, in the prior art, the heat dissipation performance of the capacitor module is poor, which affects the working performance and service life of the capacitor module.

[0042] Therefore, a new capacitor module is urgently needed to solve the problems of large size and poor heat dissipation performance of the capacitor module in the prior art.

[0043] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of this application, the singular expressions "a", "an", "said", "above", "the", and "this" are intended to also include expressions such as "one or more", unless the context clearly indicates otherwise.

[0044] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0045] Figure 1 is a schematic structural diagram of a capacitor core package in a capacitor module provided in an embodiment of the present application, and Figure 2 is a schematic structural diagram of a capacitor module provided in an embodiment of the present application without showing the packaging plate and the radiator. Referring to Figures 1 and 2, the capacitor module includes a housing 2 and a capacitor core package assembly 1, and the housing 2 includes a receiving cavity 20 with an opening at one end, and the receiving cavity 20 accommodates the capacitor core package assembly 1. The capacitor core package assembly 1 includes a plurality of capacitor core packages 10, and there is a gap between each two adjacent capacitor core packages 10. Figure 2a is a schematic structural diagram of a capacitor core package in this embodiment, and Figure 2b is another schematic structural diagram of a capacitor core package in this embodiment. Referring to Figures 1, 2, 2a and 2b, the capacitor core package 10 includes an anode foil 10b, a cathode foil 10a, an electrolytic paper 10d and a stop tape 10c, the electrolytic paper 10d is located between the anode foil 10b and the cathode foil 10a, the cathode foil 10a is located between the anode foil 10b and the electrolytic paper 10d, and the anode foil 10b is located between the two electrolytic papers 10d. For ease of understanding, the direction perpendicular to the bottom wall of the housing 2 is referred to below as a first direction. In one embodiment, along the first direction X, the length of the anti-roll tape 10c is less than the length of the cathode foil 10a, so that the cathode foil 10a is partially exposed on the surface of the capacitor core package 10. In one embodiment, along the first direction X, the length of the cathode foil 10a is greater than the lengths of the anti-roll tape 10c and the anode foil 10b, so that the cathode foil 10a is partially exposed on the surface of the capacitor core package 10.

[0046] In one embodiment, when the capacitor core package 10 is disposed in the accommodating cavity 20, the exposed portion 102 of the cathode foil of each capacitor core package 10 is located at the opening of the capacitor core package 10 away from the shell, and the exposed portion 102 of the cathode foil is used to contact the shell 2 to transfer the heat generated by the capacitor core package 10 to the shell 2. Specifically, the cathode foil included in the capacitor core package 10 is in direct contact with the shell 2, which can increase the speed of heat generated by the capacitor core package 10 to dissipate through the shell 2, improve the heat dissipation efficiency of the capacitor core package 10, and thereby improve the heat dissipation efficiency of the capacitor module 1, and also increase the service life of the capacitor module 1. In addition, multiple capacitor core packages 10 are arranged in a accommodating cavity 20 included in the shell 2, and there is a gap between each two adjacent capacitor core packages 10. When the number of capacitor core packages 10 included in the capacitor module of the present application is the same as the number of discrete capacitors included in the capacitor module in the prior art, since the two adjacent discrete capacitors are separated by an aluminum plate, the volume of the capacitor module in the prior art is larger. However, the capacitor module in the present application integrates multiple capacitor core packages 10 into a accommodating cavity 20, which can save the space occupied by the aluminum plate, thereby reducing the volume of the capacitor module.

[0047] It is worth mentioning that the shape of the capacitor core package 10 can be, but is not limited to, cylindrical or rectangular. When the capacitor core package is rectangular, the capacitor core package is prepared by a winding or lamination process.

[0048] In one embodiment, Figure 3 is a schematic diagram of the structure of a capacitor core package assembly in a capacitor module provided by an embodiment of the present application. Referring to Figures 2 and 3, the capacitor module further includes a positioning plate 11, upon which multiple capacitor core packages 10 can be integrated. Specifically, the bottom surface of the capacitor core package 10 can be secured to the positioning plate 11 by adhesive bonding. At this point, the exposed portion 102 of the cathode foil of the capacitor core package 10 contacts the sidewall of the housing. Alternatively, the surface of the positioning plate 11 includes a plurality of positioning portions, and there are gaps between the plurality of positioning portions. The positioning portions may be, but are not limited to, card slots or limit slots, etc., that is, a plurality of groove portions are provided on the surface of the positioning plate 11 so that the capacitor core package 10 can be clamped in the positioning portion, and the exposed portion 102 of the cathode foil of the capacitor core package 10 passes through the positioning plate 11 and contacts the shell 2. In this way, before the plurality of capacitor core packages 10 are installed in the accommodating cavity of the shell, the plurality of capacitor core packages 10 can be integrated into the positioning plate 11 by bonding or clamping. In this way, the capacitor core package assembly 1 can be prefabricated, and the components in the capacitor module can be modularized, thereby improving the convenience of assembling the capacitor module.

[0049] In one embodiment, Figure 4 is a schematic structural diagram of the shell in the capacitor module provided in an embodiment of the present application. Referring to Figures 1 and 4, the shell 2 includes a plurality of support columns 21, the plurality of support columns 21 are distributed in an array, the plurality of support columns 21 are fixed to the bottom wall of the shell 2, and the plurality of support columns 21 are integrally formed with the shell 2. Each capacitor core package 10 includes a center hole 103, and the axis of the center hole 103 coincides with the center line of the capacitor core package 10. Among them, the axis of the center hole 103 and the center line of the capacitor core package 10 both extend along the first direction X. The capacitor core package 10 is passed through the center hole 103 on the support column 21. At this time, the exposed portion 102 of the cathode foil of the capacitor core package 10 is in contact with the bottom wall of the shell 2.

[0050] It is worth mentioning that the multiple support columns 21 are perpendicular to the bottom wall of the shell 2, and the height of the multiple support columns 21 along the first direction X may be less than the length of the center hole 103, or the height of the multiple support columns is greater than the length of the center hole 103. The multiple support columns 21 are used to limit the movement of the multiple capacitor core packages 10 perpendicular to the first direction X.

[0051] 2 and 4 , the capacitor module further includes a pressing plate 3, which includes a plurality of fixing holes. The gap between two adjacent fixing holes in the plurality of fixing holes is the same as the gap between two adjacent support columns 21 in a row of support columns 21, wherein the pressing plate 3 covers the end of the capacitor core package assembly facing the opening. The plurality of fixing holes cooperate with the portion of the support column 21 passing through the capacitor core package 10, and the capacitor core package 10 is clamped between the pressing plate 3 and the bottom wall of the housing 2 by a locking member. The locking member is a nut or a locking clamp. When the locking member is a nut, the end of the support column 21 away from the bottom wall of the housing 2 includes a thread so that the nut cooperates with the support column 21 to fix the capacitor core package 10. Correspondingly, when the locking member is a locking clip, the end of the support column 21 away from the bottom wall of the shell 2 can be the same as the end of the support column 21 close to the bottom wall of the shell 2. The locking clip clamps the part of the support column 21 extending out of the pressure plate 3 to fix the capacitor core package 10, thereby improving the stability of the capacitor core package 10.

[0052] It is worth mentioning that there can be multiple pressing plates 3 to fix the multiple capacitor core packages 10 distributed in an array and limit the movement of the capacitor core packages 10 along the first direction X.

[0053] In the above embodiment, referring to Figure 3 again, the capacitor module also includes a bus, which includes a positive bus 4 and a negative bus 5. The positive bus 4 and the negative bus 5 are fixedly connected by an insulating structural member. The positive bus 4 connects the anode foil guide strips 100 of the capacitor core packages 10 in the same row in series, and the positive bus 4 also connects the anode foil guide strips 100 of multiple rows of capacitor core packages 10 in parallel. The negative bus 5 connects the cathode foil guide strips 101 of the capacitor core packages 10 in the same row in series, and the negative bus 5 also connects the cathode foil guide strips 101 of multiple rows of capacitor core packages 10 in parallel to achieve series and parallel connection between multiple capacitor core packages 10.

[0054] It is worth mentioning that the materials of the positive bus bar 4 and the negative bus bar 5 can be but are not limited to aluminum or copper, and there are many ways to connect the positive bus bar 4 and the anode foil guide strip 100, such as: the positive bus bar 4 and the anode foil guide strip 100 are connected by welding, riveting or crimping. Similarly, the negative bus bar 5 and the cathode foil guide strip 101 can also be connected by welding, riveting or crimping.

[0055] In the above-mentioned embodiment, Figure 5 is a structural schematic diagram of the capacitor module provided in the embodiment of the present application. Referring to Figures 3 and 5, the capacitor module also includes a packaging plate 6, which is connected to the opening of the shell 2, that is, the packaging plate 6 is connected to the opening of the accommodating cavity, so that the packaging plate and the shell are enclosed to form a closed accommodating cavity. More specifically, the packaging plate 6 can be fixedly connected to the shell 2 by welding (laser welding, resistance welding or ultrasonic welding) to seal the capacitor core package assembly 1, the positive bus 4, the negative bus 5 and the pressure plate located in the accommodating cavity in the shell 2. In this way, the multiple capacitor core packages 10 included in the capacitor core package assembly 1 are packaged by a sealing plate 6. Compared with the capacitor module including multiple discrete capacitors, each discrete capacitor needs to be sealed independently, which can reduce the complexity of the capacitor module preparation and reduce the preparation cost. In addition, the packaging plate 6 includes a positive through hole and a negative through hole. The positive through hole is used to allow the positive terminal 40 included in the positive bus 4 to pass through, and the negative through hole is used to allow the negative terminal 50 included in the negative bus 5 to pass through. When the positive terminal 40 and the negative terminal 50 pass through the positive through hole and the negative through hole, the positive through hole and the negative through hole can also be sealed by sealant or glass to ensure the airtightness inside the shell 2.

[0056] In one embodiment, in order to insulate and isolate the anode foil strips and cathode foil strips of each capacitor core package from the shell and prevent electrical connection between the anode foil strips and cathode foil strips of each capacitor core package and the shell, an insulating layer can be filled between the packaging plate and the capacitor core package. The insulating layer can separate the anode foil strips and cathode foil strips included in each capacitor core package from the shell. When the insulating layer is specifically set, the insulating layer is filled on the side of the positive bus and the negative bus facing the packaging plate, and can also separate the anode foil strips and cathode foil strips included in each capacitor core package from the shell.

[0057] The material of the insulating layer may be, but is not limited to, glass, resin, or rubber.

[0058] In one embodiment, in order to prevent the current between the anode foil guide strip and the positive bus of the capacitor core package from being too large and causing a short circuit, the anode foil guide strip and / or the positive bus of each capacitor core package may include a fuse device. Correspondingly, in order to prevent the current between the cathode foil guide strip and the negative bus of the capacitor core package from being too large and causing a short circuit, the cathode foil guide strip and / or the negative bus of each capacitor core package may also include a fuse device, so that when the current is too large, at least one of the anode foil guide strip, the cathode foil guide strip, the positive bus or the negative bus will melt.

[0059] The fuse device may be, but is not limited to, a metal fuse, a thermal pellet, an opening, or a metal fuse short, etc. The following description will be made by taking the fuse device as an opening as an example.

[0060] Figure 6a is another schematic diagram of the structure of a capacitor core package in a capacitor module provided by an embodiment of the present application. Referring to Figure 6a, the X direction in Figure 6a represents the thickness direction of the anode foil strip 100 and the cathode foil strip 101. It can be understood that the thickness directions of the anode foil strip 100 and the cathode foil strip 101 are perpendicular to the bottom wall of the housing. To prevent excessive current from flowing through the anode foil strip 100 and the cathode foil strip 101 of the capacitor core package 10, the anode foil strip 100 includes a first opening 1000. The first opening 1000 serves as a fuse device within the anode foil strip 100. The first opening 1000 extends through the anode foil strip 100 along its thickness. The cathode foil strip 101 includes a second opening 1010. The second opening 1010 serves as a fuse device within the cathode foil strip 101. The second opening 1010 penetrates the cathode foil strip 101 along the thickness direction of the cathode foil strip 101. The provision of the first opening 1000 and the second opening 1010 can reduce the local flow area of ​​the anode foil strip 100 and the cathode foil strip 101. When the current of the anode foil strip 100 and the cathode foil strip 101 is too large, the first opening 1000 of the anode foil strip 100 will melt, and the second opening 1010 of the cathode foil strip 101 will melt, thereby preventing the current of the anode foil strip 100 and the cathode foil strip 101 from being too large.

[0061] FIG6b is a structural schematic diagram of a capacitor core package assembly in a capacitor module provided in an embodiment of the present application. Referring to FIG6b , the positive busbar 4 includes a third opening 41, and the third opening 41 penetrates the positive busbar 4 along the thickness direction of the positive busbar 4. The third opening 41 is a fuse device included in the positive busbar 4. There can be two third openings 41, and the two third openings 41 are located on both sides of the positive terminal 40 included in the positive busbar 4. The provision of the third opening 41 can reduce the local flow area of ​​the positive busbar 4. When the current of the positive busbar 4 is too large, the third opening 41 included in the positive busbar 4 is fused to prevent the current of the positive busbar 4 from being too large.

[0062] The negative electrode busbar 5 includes a fourth opening 51, which extends through the thickness of the negative electrode busbar 5 and serves as a fuse. Two fourth openings 51 may be provided, one on each side of the negative electrode terminal 50. The provision of the fourth openings 51 reduces the local flow area of ​​the negative electrode busbar 5. When the current flowing through the negative electrode busbar 5 is excessive, the fourth openings 51 on the negative electrode busbar 5 fuse, thereby preventing excessive current from flowing through the negative electrode busbar 5.

[0063] In the above-mentioned embodiment, Figure 7 is a structural schematic diagram of the radiator in the capacitor module provided in the embodiment of the present application; Figure 8 is another structural schematic diagram of the capacitor module provided in the embodiment of the present application. Referring to Figures 7 and 8, in order to ensure that the heat generated by the capacitor core package can be quickly dissipated, the capacitor module also includes a radiator 7, and the radiator 7 is arranged on one side of the shell 2. Specifically, the radiator 7 is located on the side of the opening away from the accommodating cavity included in the shell 2, so as to facilitate the installation between the shell 2 and the radiator 7. Among them, the space between the radiator 7 and the shell 2 is filled with thermally conductive insulating glue or thermally conductive silicone pads, which can reduce the thermal resistance between the shell 2 and the radiator 7 and improve the heat dissipation effect between the shell 2 and the radiator 7.

[0064] The shell 2 and the radiator 7 can be connected by potting fixing glue, or the shell 2 can include a connecting portion 22, which is arranged on the side of the opening away from the accommodating cavity. The connecting portion 22 can be a limit block, which includes multiple positioning holes. Bolts or other connecting parts can pass through the positioning holes to fix the radiator 7 to the shell.

[0065] In the above-described embodiment, referring to Figures 5 and 8 , the packaging board 6 includes at least one pressure relief valve 60. When the pressure within the capacitor module increases, the pressure relief valve 60 opens, i.e., the pressure relief valve 60 cracks, thereby releasing the pressure within the capacitor module. The pressure relief valve 60 is specifically a thinned portion formed on the packaging board. For example, the thinned portion can be a location where a groove is formed on the packaging board. The groove can be cross-shaped or in another shape.

[0066] In one embodiment, each capacitor core package can be connected in parallel with a voltage divider resistor, and a thermistor can be inserted into each capacitor core package. A monitoring chip can be built into the capacitor module. The monitoring chip is used to monitor the voltage divider and temperature of each capacitor core package and can generate an alarm in a timely manner.

[0067] In the above embodiment, when the multiple capacitor core packages include aluminum capacitor core packages and film capacitor core packages, the capacitor module with the multiple capacitor core packages can filter high-frequency ripple and low-frequency ripple at the same time.

[0068] The capacitor module provided in this application can be specifically applied to a power converter. The power converter includes a power module and the above-mentioned capacitor module, the power module is electrically connected to the capacitor module, and the power module is used to convert the direct current output by the capacitor module into alternating current. In some embodiments, the power converter can be applied to the field of electric vehicles. Specifically, the power converter is applied to the motor controller included in the electric vehicle. At this time, the capacitor module can correspond to the low-frequency ripple voltage caused by the back electromotive force of the motor, and play the role of filtering and smoothing the voltage for the main circuit and providing reactive power compensation. In some embodiments, the power converter can also be applied to the photovoltaic field. Specifically, the power converter can be applied to photovoltaic systems. In some embodiments, the power converter can also be used in charging piles.

[0069] In one embodiment, referring to Figures 1, 3 and 5, multiple capacitor core packages 10 are distributed in an array on a positioning plate 11, that is, the surface of the positioning plate 11 integrates multiple capacitor core packages 10, and there is a gap between two adjacent capacitor core packages 10. The positioning plate 11 is installed in a hollow accommodating cavity, the positive bus 4 connects the anode foil guide strips 100 of the multiple capacitor core packages, and the negative bus 5 connects the cathode foil guide strips 101 of the multiple capacitor core packages 10. The packaging plate 6 covers the opening of the accommodating cavity to seal the accommodating cavity to form a sealed accommodating cavity, that is, multiple capacitor core packages 10 are sealed in one accommodating cavity, and there is no need to seal each independent capacitor core package 10 separately, so as to improve the sealing efficiency. In addition, when the packaging plate 6 seals multiple capacitor core packages 10 in the accommodating cavity, the packaging plate 6 can be provided with positive through-holes and negative through-holes for the positive electrode terminals 40 included in the positive bus 4 and the negative electrode terminals 50 included in the negative bus 5 to pass through, so that the positive electrode terminals 40 and the negative electrode terminals 50 are exposed to the outside of the capacitor module. In order to improve the safety of the capacitor module, multiple pressure relief valves 60 can be provided on the surface of the packaging plate 6. The multiple pressure relief valves 60 are distributed in an array, and each pressure relief valve 60 can correspond to a capacitor core package 10.

[0070] In another embodiment, referring to Figures 1, 2, 4 and 8, the shell 2 includes multiple rows of support columns 21, which are fixed to the bottom wall of the accommodating cavity 20. Multiple capacitor core packages 10 are passed through one support column 21. The pressing plate 3 cooperates with the part of the support portion passing through the capacitor core package 10 to fix the capacitor core package 10 in the shell 2. The positive bus connects the anode foil guide strips of the multiple capacitor core packages, and the negative bus connects the cathode foil guide strips of the multiple capacitor core packages. The packaging plate 6 covers the opening of the accommodating cavity 20 to seal the accommodating cavity, that is, multiple capacitor core packages 10 are sealed in one accommodating cavity, and there is no need to seal each independent capacitor core package 10 separately, so as to improve the sealing efficiency. In addition, when the packaging plate 6 seals the multiple capacitor core packages 10 in the accommodating cavity 20, the side wall of the housing 2 may include two lead-out holes 23. The positive electrode terminal 40 included in the positive bus and the negative electrode terminal 50 included in the negative bus pass through the lead-out holes 23, so that the positive electrode terminal 40 and the negative electrode terminal 50 are exposed to the outside of the capacitor module. Accordingly, in this embodiment, a pressure relief valve 60 can be provided on the surface of the packaging plate 6 to improve the safety of the capacitor module.

[0071] Obviously, those skilled in the art may make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include these modifications and variations.

Claims

1. A capacitor module, characterized in that: Including a shell and a capacitor core package assembly; The housing comprises a receiving cavity with one end open, and the receiving cavity receives the capacitor core package assembly; The capacitor core package assembly includes a plurality of capacitor core packages, with a gap between two adjacent capacitor core packages, and the capacitor core package includes a cathode foil, wherein a portion of the cathode foil is exposed on a surface of an end of the capacitor core package away from the opening, and the exposed portion of the cathode foil is in contact with the shell.

2. The capacitor module according to claim 1, wherein: The capacitor core package further comprises an anode foil and a roll-stop belt, wherein the roll-stop belt is located on the outer peripheral side of the capacitor core package; The cathode foil is located between the anode foil and the anti-rolling belt, and along the first direction, the length of the anti-rolling belt is smaller than the length of the cathode foil; or The anode foil is located between the cathode foil and the anti-rolling belt, and along the first direction, the length of the cathode foil is greater than the length of the anti-rolling belt and the anode foil; Wherein, the first direction is a direction perpendicular to the bottom wall of the shell.

3. The capacitor module according to claim 1, wherein: The capacitor module further includes a positioning plate, which includes a plurality of positioning portions, a gap exists between two adjacent positioning portions, and each positioning portion fixes one capacitor core package.

4. The capacitor module according to claim 1, wherein: The capacitor module also includes a plurality of support columns arranged in an array, and the plurality of support columns are fixed on the bottom wall of the shell; each of the capacitor core packages includes a center hole, and along a first direction, the center hole penetrates the capacitor core package, and the plurality of support columns are respectively penetrated through the center holes of the plurality of capacitor core packages; wherein the first direction is a direction perpendicular to the bottom wall of the shell.

5. The capacitor module according to claim 4, characterized in that: The capacitor module also includes a pressure plate, which includes a plurality of fixing holes. There is a gap between two adjacent fixing holes. The pressure plate covers the end of the capacitor core package assembly facing the opening, and the ends of the plurality of support columns away from the bottom wall are respectively fixedly connected to the plurality of fixing holes.

6. The capacitor module according to any one of claims 1 to 5, characterized in that: The capacitor core package assembly also includes a positive bus and a negative bus, wherein the positive bus is connected to the anode foil guide strips of the multiple capacitor core packages, and the negative bus is connected to the cathode foil guide strips of the multiple capacitor core packages, wherein the positive bus and the negative bus are located at one end of the capacitor core package assembly facing the opening.

7. The capacitor module according to claim 6, characterized in that: The anode foil strip includes a fuse; or, The positive busbar includes a fuse; or, The cathode foil strip includes a fuse; or, The negative busbar includes a fuse device.

8. The capacitor module according to claim 7, characterized in that: The anode foil strip comprises a first opening, and the first opening penetrates the anode foil strip along the thickness direction of the anode foil strip; or, The cathode foil strip comprises a second opening, and the second opening penetrates the cathode foil strip along the thickness direction of the cathode foil strip; or, The fuse device included in the positive electrode busbar is a third opening, and the third opening penetrates the positive electrode busbar along the thickness direction of the positive electrode busbar; or, The fuse device included in the negative electrode busbar is a fourth opening, and the fourth opening penetrates the negative electrode busbar along the thickness direction of the negative electrode busbar.

9. The capacitor module according to any one of claims 6 to 8, characterized in that: The capacitor module further comprises a packaging plate, wherein the packaging plate is fixedly connected to the opening of the shell, and the packaging plate and the shell are enclosed to form a closed accommodating cavity.

10. The capacitor module according to claim 9, wherein: The positive busbar includes a positive electrode terminal, and the negative busbar includes a negative electrode terminal. Both the positive electrode terminal and the negative electrode terminal pass through the packaging plate, or the positive electrode terminal and the negative electrode terminal pass through the side wall of the shell.

11. The capacitor module according to claim 10, wherein: The capacitor module also includes an insulating layer, and the insulating layer is located between the capacitor core package component and the packaging plate.

12. The capacitor module according to any one of claims 9 to 11, characterized in that: The packaging plate includes at least one pressure relief valve.

13. The capacitor module according to claim 12, wherein: There is one pressure relief valve, and the pressure relief valve is arranged at the center of the packaging plate; or, There are multiple pressure relief valves, and the multiple pressure relief valves are arranged in an array.

14. The capacitor module according to any one of claims 1 to 13, characterized in that: The capacitor module also includes a heat sink, and the heat sink is arranged in contact with the bottom wall of the shell.

15. The capacitor module according to any one of claims 1 to 14, characterized in that: The capacitor core package is cylindrical or rectangular.

16. A power converter, characterized in that: It comprises a power module and a capacitor module as claimed in any one of claims 1 to 15, wherein the power module is electrically connected to the capacitor core package component, and the power module is arranged on a side of the capacitor module away from the bottom wall of the shell.

Images