Composite busbar type flexible direct current capacitor

Abstract

The invention discloses a composite busbar type flexible direct current capacitor, and relates to the field of capacitors. A vibration reduction connecting piece is arranged between a busbar and a capacitor core, so that the impact resistance and vibration resistance of the capacitor core are improved, impact force can be dispersed to part of the core or a single core, the impact force is eliminated through the vibration reduction connecting piece, and the service life of the capacitor is prolonged. And the risk of displacement, fracture or capacitance loss of the core is reduced. A current-conducting plate is changed into the busbar arranged at the edge of the shell, and the capacitor cores are divided into a plurality of groups through the extended connecting plates, so that impact force is dispersed and eliminated. The arc-shaped groove is arranged at the joint of the connecting plate and the busbar, so that the breaking risk is reduced, and the reliability of the busbar and the connecting plate is improved. The first thrust elastic piece and the second thrust elastic piece are used for counteracting impact force, and then part of the force is transmitted to the supporting plate and is further counteracted through the external damping device, so that the impact resistance of the capacitor is enhanced. And the adjacent capacitor cores on the connecting plate are connected with other cores through the elastic ropes, so that the impact resistance of the capacitor is enhanced.

Description

Technical Field

[0001] The present invention relates to the field of capacitors, and in particular to a composite busbar type flexible capacitor. Background Art

[0002] With the rapid progress of domestic ionization electronic technology, conversion technology has been widely used in many fields such as smart grid, flexible DC transmission, high-voltage and high-power inverters, and rail transit. These applications have gradually increased the technical requirements for converters, especially the DC support capacitor as one of the core components of the converter, and its performance requirements are also constantly increasing. As the conversion technology develops in the direction of high power and large capacity, the capacity of the DC support capacitor is gradually increasing. In order to meet the needs of high-power converters, the DC support capacitor in the prior art usually increases the capacity to meet higher power requirements, resulting in a further increase in the volume of the capacitor. However, this increase in volume not only affects the external impact and vibration resistance of the capacitor. In order to cope with this problem, the prior art generally adopts the installation of vibration reduction devices on the outside of the capacitor, such as springs, foams and other vibration reduction materials. These vibration reduction measures can effectively reduce the impact between the capacitor and the surrounding equipment, but their role is limited to reducing external impact.

[0003] However, as the capacity of capacitors gradually increases, not only the external volume of the capacitor increases, but also the internal capacitor core increases, and the number continues to increase. As a result, the impact resistance of the capacitor decreases, and there is a risk of internal damage due to vibration. This internal damage may cause the performance of the capacitor to deteriorate or even fail, affecting the normal operation of the converter. Therefore, relying solely on external vibration reduction devices cannot meet the needs of modern high-power capacitors. It is urgent to innovate the internal design and materials of the capacitor to improve its overall impact and vibration resistance, and ensure that the capacitor can operate stably and reliably in more harsh working environments. Summary of the invention

[0004] The present invention provides a composite busbar type flexible capacitor to solve the problem in the prior art that the internal impact and vibration resistance of the capacitor is low due to the increase in the volume of the capacitor, the increase in the volume and the number of the internal capacitor cores.

[0005] To achieve the above object, the present invention provides the following solutions: A composite busbar type flexible DC capacitor comprises a shell, a busbar and a capacitor core installed in the shell, wherein the busbar and the capacitor core are connected via a plurality of vibration-damping connectors.

[0006] The present invention improves the impact and vibration resistance of the capacitor core by arranging a vibration-damping connector between the busbar and the capacitor core. In the prior art, all capacitor cores are usually welded as a whole. Therefore, when the capacitor is impacted, the internal capacitor core is also subjected to the impact force. As the volume and length of the capacitor core increase, the capacitor core is likely to be displaced or broken due to the impact force, resulting in collision with adjacent capacitor cores, which poses a risk of loss of capacity. By arranging a vibration-damping connector between the busbar and the capacitor core, the impact force on the capacitor can be dispersed to part or even a single capacitor core, and then the vibration-damping connector that fixes the capacitor core eliminates the impact force, thereby reducing the risk of displacement, breaking or loss of capacity of the capacitor core and improving the reliability of the flexible DC capacitor.

[0007] Furthermore, the vibration-damping connector includes a plurality of connecting plates fixedly connected to the busbar, and arc-shaped grooves are provided at both ends of the connecting plates on a side close to the busbar.

[0008] The busbar in the prior art is usually a whole conductive plate, and the capacitor cores are arranged at one time and welded to the conductive plate, so that the capacitor cores are connected in parallel to each other through the conductive plate to form a whole, which leads to a decrease in its impact resistance. The present solution divides the capacitor cores into multiple groups by replacing the conductive plate with a busbar arranged at the edge of the shell, extending multiple connecting plates from the busbar, and then welding the capacitor cores to the connecting plates, thereby dispersing the impact force on the whole, eliminating the impact force through the elasticity of the suspended connecting plates, and providing an arc-shaped groove at the connection portion where the connecting plate is connected to the busbar, thereby reducing the risk of the connecting plate being broken due to excessive impact, thereby improving the reliability of the busbar and the connecting plate.

[0009] Furthermore, a first thrust elastic member is installed between adjacent connecting plates.

[0010] In order to ensure the strength of the connection plate, the elasticity it can provide is limited. Therefore, the present invention sets a first thrust elastic member between two adjacent connection plates. The first thrust elastic member improves the impact resistance of the connection plate, further improves the impact resistance of the capacitor as a whole, and makes the composite busbar flexible capacitor have better working stability.

[0011] Furthermore, the shell includes a side plate, a plurality of support plates are provided on the inner side of the side plate, the support plates are embedded between adjacent connecting plates, and a plurality of second thrust elastic members are provided between the support plates and the connecting plates.

[0012] Under the action of the first thrust elastic member, a linkage is formed between the two adjacent connecting plates, which can transmit and share the impact force they receive to each other. However, there is always an upper limit, that is, when the impact force received by one of the connecting plates reaches the critical point of being damaged, and the adjacent connecting plate transmits part of the impact force to it, it is very likely to cause damage to this connecting plate. Therefore, in order to increase the upper limit of the impact resistance of the connecting plate, a support plate is provided between the two adjacent connecting plates. When the connecting plate is subjected to an impact force, a part of it can be offset by the first thrust elastic member and the second thrust elastic member, and then transmitted to the support plate through the second thrust elastic member. The support plate is connected to the capacitor housing, so part of the impact force can be directly transmitted to the outside of the capacitor and offset by the external vibration reduction device in the prior art, thereby further enhancing the impact resistance of the capacitor.

[0013] Furthermore, the busbar includes a positive busbar and a negative busbar, the connecting plates on the positive busbar and the negative busbar correspond one to one, the two ends of the capacitor core are respectively fixedly connected to the corresponding connecting plates, and a plurality of elastic ropes are sleeved on two capacitor cores installed on adjacent connecting plates.

[0014] Connecting capacitor cores welded on two adjacent connecting plates by means of elastic ropes can also offset the impact force on part of the capacitor cores, and can also provide a certain connection force for all capacitor cores, thereby reducing the possibility of collision between adjacent capacitor cores.

[0015] Furthermore, the capacitor cores installed on two adjacent connecting plates are staggered, and the elastic rope is sleeved on the one and / or two capacitor cores closest to any capacitor core on the adjacent connecting plates.

[0016] After the capacitor cores are staggered, a triangular arrangement is formed between two adjacent capacitor cores on the same connecting plate and the closest capacitor core on the adjacent connecting plate. Two adjacent capacitor cores on the same connecting plate are respectively connected to the closest capacitor core on the adjacent connecting plate through elastic ropes to form a triangular stable structure. All capacitor cores are connected together through this connection method, thereby enhancing the impact resistance of all capacitor cores.

[0017] Furthermore, the connecting plate is provided with a plurality of welding holes for welding to the capacitor core, and the welding holes include a contact portion and two bifurcated portions.

[0018] The capacitor core is welded to the connecting plate by injecting solder into the welding hole. The contact area is large to ensure full contact between the capacitor core, the connecting plate and the solder. The forked portion not only increases the solder contact area, but also enables the solder to present an irregular shape, thereby enhancing the solder's impact resistance and reducing the possibility of desoldering.

[0019] Furthermore, the two bifurcated portions are arranged in parallel, and an arc-shaped protrusion is provided between the bifurcated portion and the contact portion.

[0020] By arranging a protrusion between the bifurcated portion and the contact portion, after the solder is filled in the welding hole, the adjacent portion between the solder in the bifurcated portion and the solder in the contact portion is not easily broken, thereby improving the impact resistance of the solder.

[0021] Furthermore, the capacitor cores are connected in parallel with each other through the connecting plate and then connected to the external circuit through the busbar and the lead-out terminal in sequence. In order to reduce the contact resistance of the welding part when the capacitor cores are connected in parallel and improve the welding stability between the capacitor core and the connecting plate, the capacitor core corresponds to a plurality of the welding holes. By corresponding one capacitor core to multiple welding holes, the welding strength between the capacitor core and the connecting plate is improved, and the risk of desoldering is reduced.

[0022] Furthermore, the bifurcated portion is arranged toward the top of the housing, so that the solder filled in the contact portion with a larger area is located at the bottom, bearing the weight of the capacitor core, reducing the possibility of desoldering while avoiding damage to the relatively fragile bifurcated solder, thereby increasing the service life of the capacitor.

[0023] Furthermore, for a flexible DC capacitor, the capacitor core installed inside is usually composed of a conductive electrode and an insulating film material, and the conductive electrode and the insulating film material are stacked. When preparing the capacitor core, the stacked film material is tightly wound into a cylindrical core by a winding machine, and the film material is ensured to be neatly and tightly fitted to avoid gaps or dislocations between the film materials, thereby improving the electrical performance and working stability of the flexible DC capacitor. Therefore, in order to ensure that the film electrode inside the capacitor core does not dislocate during the winding process, the capacitor core includes a first electrode and a second electrode stacked, the first electrode includes a first electrode layer and a first base layer, and the second electrode includes a second metal electrode layer and a second base layer. In the first electrode, the electrode material is attached to the surface of the first base layer by evaporation, sputtering or spin coating to obtain a first electrode layer; in the second electrode, the electrode material is also attached to the surface of the second base layer by evaporation, sputtering or spin coating to obtain a second electrode layer. The first electrode layer and the first base layer, as well as the second electrode layer and the second base layer, are tightly connected, which effectively avoids the existence of gaps or misalignments between the conductive electrode layer and the insulating film material during the winding process of the capacitor core, thereby improving the electrical performance and working stability of the composite busbar flexible capacitor.

[0024] Furthermore, the first electrode layer and / or the second electrode layer attached to the surface of the insulating base layer are at risk of cracking due to mechanical stress during the winding process of the capacitor core. At the same time, temperature changes and mechanical vibrations during the use of the flexible DC capacitor will also increase the risk of cracking of the first electrode layer and / or the second electrode layer. The cracking of the electrode layer in the capacitor core will affect the electrical properties of the flexible DC capacitor, resulting in poor electrical contact, breakdown or failure. Therefore, in order to avoid the risk of cracking of the first electrode layer and / or the second electrode layer, the first electrode layer and / or the second electrode layer are a multi-layer structure. When cracks appear inside the first electrode layer and / or the second electrode layer, the interlayer interface of the multi-layer electrode structure can delay the propagation of the cracks, improve the mechanical strength and flexibility of the first electrode layer and / or the second electrode layer, and thus improve the electrical performance and working stability of the composite busbar flexible DC capacitor.

[0025] Furthermore, after the capacitor core is wound, the edge of the metal film used as the electrode material will be exposed on the two circular end faces of the capacitor core. By spraying gold on the two circular end faces of the capacitor core, a uniform conductive metal layer can be formed on the two end faces of the capacitor core, providing a good electrical connection foundation for pin welding and external connection of the capacitor. The capacitor core includes a first gold-sprayed layer and a second gold-sprayed layer at both ends. After the capacitor core is wound, the first electrode layer is exposed on one circular end face of the capacitor core, and the first gold-sprayed layer is electrically connected to the first electrode layer; the second electrode layer is exposed on the other circular end face of the capacitor core, and the second gold-sprayed layer is electrically connected to the second electrode layer. In order to ensure good electrical connection between the first electrode layer and the first gold-sprayed layer, and between the second electrode layer and the second gold-sprayed layer, and to improve the performance of the composite busbar flexible capacitor, the edges of the first electrode layer and / or the second electrode layer are wavy.

[0026] One or more technical solutions provided by the present invention have at least the following technical effects or advantages: (1) The present invention improves the impact and vibration resistance of the capacitor core by arranging a vibration-damping connector between the busbar and the capacitor core. By arranging a vibration-damping connector between the busbar and the capacitor core, the impact force on the capacitor can be dispersed to part or even a single capacitor core, and then the vibration-damping connector that fixes the capacitor core eliminates the impact force, thereby reducing the risk of displacement, breakage or loss of capacity of the capacitor core. (2) By replacing the conductive plate with a busbar arranged at the edge of the shell, extending multiple connecting plates from the busbar, and then welding the capacitor core to the connecting plates, the capacitor core is divided into multiple groups, the impact force on the whole is dispersed, and the impact force is eliminated by the elasticity of the suspended connecting plates. An arc-shaped groove is provided at the connection point between the connecting plate and the busbar, which reduces the risk of the connecting plate being broken due to excessive impact, thereby improving the reliability of the busbar and the connecting plate; (3) A portion of the impact force is offset by the first thrust elastic member and the second thrust elastic member, and then part of the impact force is transmitted to the support plate by the second thrust elastic member, and the support plate is connected to the capacitor housing. Therefore, part of the impact force can be directly transmitted to the outside of the capacitor and offset by the external vibration reduction device in the prior art, thereby further enhancing the impact resistance of the capacitor; (4) Two adjacent capacitor cores on the same connecting plate are connected to the closest capacitor core on the adjacent connecting plate through elastic ropes to form a triangular stable structure. All capacitor cores are connected together through this connection method, thereby enhancing the impact resistance of all capacitor cores; (5) The capacitor core is welded to the connecting plate by injecting solder into the welding hole. The contact area is large to ensure that the capacitor core, the connecting plate and the solder are in full contact. The fork portion can not only increase the solder contact area, but also make the solder present an irregular shape, thereby enhancing the impact resistance of the solder and reducing the possibility of desoldering. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of the present invention, and do not constitute a limitation on the embodiments of the present invention; Figure 1 is a cross-sectional view of the internal structure of the capacitor in the present invention; Figure 2 yes Figure 1 A magnified image of the middle part; Figure 3 It is a schematic diagram of the arrangement of the capacitor core in the present invention; Figure 4 It is a schematic diagram of the welding hole structure in the present invention; Among them, 1-shell, 101-support plate, 2-busbar, 3-capacitor core, 401-connecting plate, 402-arc-shaped groove, 5-first thrust elastic member, 6-second thrust elastic member, 7-elastic rope, 8-welding hole, 801-contact part, 802-fork part, 803-arc-shaped protrusion. DETAILED DESCRIPTION

[0028] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those within the scope of this description. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0030] Embodiment 1 This embodiment provides a composite busbar type flexible capacitor, such as Figure 1-Figure 4 As shown, it includes a housing 1 and a busbar 2 and a capacitor core 3 installed in the housing 1, and the busbar 2 and the capacitor core 3 are connected through a plurality of vibration-damping connecting members.

[0031] Among them, the shell 1 is provided with 8 M12 internal thread lead-out terminals, 4 of which are one pole, and the busbar 2 has a positive busbar and a negative busbar, which are respectively connected to the 4 lead-out terminals. The shell 1 is also equipped with a pressure sensor (threshold value set at 40kPa) and a pressure relief valve (action threshold value 30kPa), which have the function of monitoring the operating status of the capacitor at all times. Under the dual protection of the sensor and the pressure relief valve, the product is safer and more reliable. The shell 1 is made of 304 non-magnetic stainless steel, which has high strength, will not rust, and is not affected by the electric and magnetic fields of the surrounding environment. The shell body, shell cover and shell bottom are welded by argon arc welding, and the welding strength is much greater than the pressure of the product under 40kPA; the capacitor core 3 is produced by a winding process, and after gold spraying and heat setting, it is welded through the busbar 2 to form a capacitor core group, and then after insulation encapsulation, it is loaded into a stainless steel shell and poured into a fully sealed dry structure with flame-retardant epoxy resin; the busbar 2 is preferably a copper bar.

[0032] In a more preferred embodiment, the vibration-damping connector includes a plurality of connecting plates 401 fixedly connected to the busbar 2 , and arc-shaped grooves 402 are provided at both ends of the connecting plates 401 on a side close to the busbar 2 .

[0033] The connecting plate 401 and the busbar 2 are preferably integrally formed by a mold to enhance the structural strength. The arc groove 402 is opened at the junction of the connecting plate 401 and the busbar 2, and the angle between the connecting plate 401 and the busbar 2 is rounded.

[0034] In a more preferred embodiment, a first thrust elastic member 5 is installed between adjacent connecting plates 401. The first thrust elastic member 5 can be a thrust spring, a rubber pad, etc. Since the first thrust elastic member 5 is connected to the same connecting plate 401, the conductivity of the first thrust elastic member 5 is not required.

[0035] In a more preferred embodiment, the shell 1 includes a side plate, a plurality of support plates 101 are provided on the inner side of the side plate, the support plates 101 are embedded between adjacent connecting plates 401, and a plurality of second thrust elastic members 6 are provided between the support plates 101 and the connecting plates 401.

[0036] Among them, the support plate 101 is preferably arranged on one side of the end of the connecting plate 401, and the second thrust elastic part 6 is a thrust spring, a rubber pad, etc. Since the support plate 101 is connected to the shell 1, insulation treatment is required. Therefore, the surface of the support plate 101 is preferably coated with an insulating coating, and the second thrust elastic part 6 is made of rubber or a thrust spring coated with an insulating coating.

[0037] In a more preferred embodiment, the busbar 2 includes a positive busbar and a negative busbar, the connecting plates 401 on the positive busbar and the negative busbar correspond one to one, the two ends of the capacitor core 3 are respectively fixedly connected to the corresponding connecting plates 401, and a plurality of elastic ropes 7 are sleeved on two capacitor cores 3 installed on adjacent connecting plates 401.

[0038] The two ends of the capacitor core 3 are preferably welded to the same level, and the elastic rope 7 is preferably a rubber rope ring.

[0039] In a more preferred embodiment, the capacitor cores 3 installed on two adjacent connecting plates 401 are staggered, and the elastic rope 7 is sleeved on the closest one and / or two capacitor cores 3 on any capacitor core 3 and the adjacent connecting plates 401 .

[0040] Among them, since there are two adjacent connecting plates on a connecting plate 401, there is a capacitor core 3 adjacent to the capacitor core 3 on the connecting plate 401 on each connecting plate. Therefore, there can be multiple elastic ropes 7 on the same capacitor core 3, and multiple elastic ropes 7 can also be set on two adjacent capacitor cores 3. Therefore, the specific number of elastic ropes 7 can be arbitrary and determined according to user needs.

[0041] Embodiment 2

[0042] On the basis of the first embodiment, a plurality of welding holes 8 for welding to the capacitor core 3 are formed on the connecting plate 401 , and the welding holes 8 include a contact portion 801 and two bifurcated portions 802 .

[0043] In order to improve the structural strength of the solder filled in the welding hole 8, the edges and corners on the side walls of the welding hole 8 are rounded.

[0044] In a more preferred embodiment, the two bifurcated portions 802 are arranged in parallel, and an arc-shaped protrusion 803 is provided between the bifurcated portion 802 and the contact portion 801. The arc-shaped protrusion 803 is also used to make the side walls of the solder filled in the welding hole 8 rounded, thereby improving the structural strength of the solder filled in the welding hole 8.

[0045] In a more preferred embodiment, the capacitor core 3 corresponds to a plurality of the welding holes 8. One end of the capacitor core 3 preferably corresponds to two welding holes 8.

[0046] In a more preferred embodiment, the bifurcated portion 802 is arranged toward the top of the housing 1 .

[0047] Furthermore, the capacitor core 3 includes a first electrode and a second electrode stacked in layers, the first electrode includes a first electrode layer and a first base layer, and the second electrode includes a second electrode layer and a second base layer. In the capacitor core 3, the first electrode layer and the second electrode layer serve as two plates of the capacitor. The first base layer attached to the first electrode layer is sandwiched between the first electrode layer and the second electrode layer as a dielectric material between the capacitor plates. The second base layer attached to the second electrode layer is used to prevent the first electrode from contacting the second electrode during the winding process, thereby preventing the capacitor from short-circuiting.

[0048] Before winding the capacitor core 3, only the first electrode and the second electrode need to be stacked, and there is no need to repeatedly stack the conductive electrode and the insulating film material. The first electrode layer and the first base layer, and the second electrode layer and the second base layer are tightly connected, which further ensures that the film electrode inside the capacitor core 3 after winding does not dislocate during the winding process, thereby improving the electrical performance and working stability of the composite busbar flexible capacitor.

[0049] Among them, the first electrode layer and / or the second electrode layer can be any metal electrode layer that can form an electrode, such as titanium, aluminum, zinc, etc., or any non-metal electrode layer that can form an electrode, such as carbon nanotubes, conductive polymers, etc. The specific material of the first electrode layer and / or the second electrode layer is determined according to actual needs, and this embodiment does not make specific restrictions here; the first base layer and / or the second base layer can be a polypropylene film, a polyester film or a polyimide film, and the first base layer and / or the second base layer are preferably high-insulation polypropylene films, whose dielectric strength is 800V / μm, dielectric loss is about 0.02%, and temperature resistance reaches 125°C. Preferably, the thickness of the first base layer and / or the second base layer is 3.4 to 10μm, and the length and width of the first base layer and / or the second base layer are determined according to the actual size of the composite busbar flexible capacitor, and this embodiment does not make specific restrictions here.

[0050] Specifically, when the first electrode layer and / or the second electrode layer is a metal electrode layer, the first electrode layer and / or the second electrode layer are attached to the corresponding insulating base surface by a vapor deposition method in physical vapor deposition technology. The vapor deposition process is carried out in a vacuum environment, the metal to be vapor deposited is placed in an evaporation source, and the metal layer is heated to the evaporation temperature by resistance heating or electron beam heating, so that metal atoms evaporate from the surface of the solid metal source, diffuse in the vacuum in the form of atoms or small molecules, and finally deposit on the surface of the insulating base. The thickness of the first electrode layer and / or the second electrode layer can be controlled by the vapor deposition time and the vapor deposition temperature. The vapor deposition time and the vapor deposition temperature are determined according to actual needs, and this embodiment is not specifically limited here. After the vapor deposition is completed, the metal layer is solidified on the surface of the insulating base to form a uniform and dense metal electrode layer. After annealing, the first electrode layer and / or the second electrode layer have good adhesion and electrical properties, so that the composite busbar flexible capacitor has good electrical properties and working stability.

[0051] Specifically, when the first electrode layer and / or the second electrode layer is a non-metallic electrode layer, that is, the electrode material is a non-metallic material such as conductive ceramics, metal oxides, conductive polymers, etc., the first electrode layer and / or the second electrode layer are attached to the corresponding insulating base surface by sputtering deposition. Sputtering deposition is to sputter out atoms or molecules of the target material by high-energy particles hitting the target material, and deposit them on the surface of the insulating base to form a uniform and dense non-metallic electrode layer.

[0052] Specifically, when the first electrode layer and / or the second electrode layer is a non-metallic electrode layer, that is, the electrode material is a non-metallic material such as carbon nanotubes, graphene, conductive polymers, etc., the first electrode layer and / or the second electrode layer are attached to the surface of the corresponding insulating base layer by chemical vapor deposition. Chemical vapor deposition decomposes or reacts a gas precursor (usually a compound containing non-metallic elements) at high temperature to generate the required thin film material and deposit it on the insulating base layer to form a uniform and dense non-metallic electrode layer.

[0053] Furthermore, the first electrode layer and / or the second electrode layer is a multilayer structure. When the first electrode layer includes multiple sub-electrode layers, when the first electrode layer is cracked due to the mechanical stress during the winding process of the capacitor core 3 and the temperature and pressure during the operation of the capacitor, when the tiny cracks inside the first electrode layer extend from one sub-electrode layer to the next sub-electrode layer, the interface stress between the sub-electrode layers can change the crack extension direction, slow down the crack extension speed and improve the working stability of the busbar-type flexible capacitor. The internal structure of the second electrode layer is the same as the internal structure of the first electrode layer, and this embodiment will not be repeated here.

[0054] Wherein, the sub-electrode layers inside the first electrode layer and / or the second electrode layer are made of different electrode materials. When the first electrode layer and / or the second electrode layer are metal electrode layers, the sub-electrode layers can be selected as sub-metal layers with different physical and mechanical properties, such as copper, gold and other metal layers have good flexibility and ductility; aluminum and titanium metal layers have strong hardness and crack resistance. Specifically, when preparing the first electrode layer and / or the second electrode layer, a copper metal layer with strong flexibility is first evaporated on the insulating base layer, and then an aluminum metal layer with higher hardness is evaporated on the copper metal layer. The aluminum-copper metal layers obtained by the evaporation method are densely connected and have good mechanical properties. At the same time, the copper metal layer effectively alleviates the stress concentration of the aluminum metal layer and reduces the occurrence and propagation of electrode cracks.

[0055] Among them, the sub-electrode layers inside the first electrode layer and / or the second electrode layer are made of the same electrode material. When the first electrode layer and / or the second electrode layer are metal electrode layers, the sub-electrode layers can be selected as sub-metal layers of the same material. The physical properties (such as thermal expansion coefficient, hardness, ductility, etc.) between the sub-metal layers of the same material are relatively consistent, avoiding the difference in thermal stress between different metal layers, so that the electrode has good mechanical properties. Specifically, when preparing the first electrode layer and / or the second electrode layer, a thinner first metal aluminum layer is first evaporated on the insulating base layer, and then a thicker second metal aluminum layer is evaporated on the first metal aluminum layer. The thinner second metal aluminum layer has better adhesion to the insulating base layer, and the thicker first metal aluminum layer has better crack resistance. And the interface stress between the first metal aluminum layer and the second metal aluminum layer can change the crack propagation direction, slow down the crack propagation speed and improve the working stability of the busbar-type flexible capacitor.

[0056] The number of sub-electrode layers, sub-electrode materials and sub-electrode thicknesses provided inside the first electrode layer and / or the second electrode layer are determined according to actual needs and are not specifically limited in this embodiment.

[0057] Further, the capacitor core 3 includes a first gold-sprayed layer and a second gold-sprayed layer at both ends, and the edges of the first electrode and / or the second electrode are wavy. Specifically, before winding the capacitor core 3, the first electrode and the second electrode are stacked, and the first electrode and the second electrode are cut so that the first electrode and the second electrode have the same size, and the edges of the first electrode layer and the second electrode layer are wavy. After the capacitor core 3 is wound, the first electrode layer is exposed on one circular end face of the capacitor core 3, and the second electrode layer is exposed on another circular end face of the capacitor core. The gold-sprayed layer is formed after gold is sprayed on both ends of the capacitor core 3. The first gold-sprayed layer at one end of the capacitor core 3 is electrically connected to the first electrode layer, and the second gold-sprayed layer at the other end of the capacitor core 3 is electrically connected to the second electrode layer. After the first gold-sprayed layer and the second gold-sprayed layer are electrically connected to the positive busbar and the negative busbar respectively, the capacitor core 3 is connected to the external circuit by the lead-out terminal.

[0058] Although the preferred embodiments of the present invention have been described in detail herein, those skilled in the art, after understanding the basic creative concepts of the present invention, can make other changes and modifications to these embodiments without departing from the technical concept and core idea of ​​the present invention. Therefore, the attached claims should be interpreted as covering not only the preferred embodiments, but also all changes and modifications within the scope of the present invention.

[0059] Obviously, based on the technical principles and innovations of the present invention, those skilled in the art can make various reasonable changes and modifications to the present invention in the process of implementing the present invention, and these changes and modifications do not exceed the spirit and scope of the present invention. In other words, any modification and variation made within the scope of the claims of the present invention and their equivalents should be regarded as an integral part of the present invention. Therefore, the protection scope of the present invention is not limited to the specifically described embodiments, but should also include all technically feasible changes and adjustments, as long as these changes and adjustments do not deviate from the basic concept and technical solution of the present invention.

Claims

1. A composite busbar type flexible capacitor, comprising a housing (1), a busbar (2) and a capacitor core (3) installed in the housing (1), characterized in that: The busbar (2) and the capacitor core (3) are connected via a plurality of vibration-damping connecting pieces.

2. The composite busbar type flexible capacitor according to claim 1, characterized in that: The vibration-damping connecting member comprises a plurality of connecting plates (401) fixedly connected to the busbar (2), and arc-shaped grooves (402) are provided at both ends of a side of the connecting plate (401) close to the busbar (2).

3. The composite busbar type flexible capacitor according to claim 2, characterized in that: A first thrust elastic member (5) is installed between adjacent connecting plates (401).

4. The composite busbar type flexible capacitor according to claim 2, characterized in that: The housing (1) comprises a side plate, a plurality of support plates (101) are provided on the inner side of the side plate, the support plates (101) are embedded between adjacent connecting plates (401), and a plurality of second thrust elastic members (6) are provided between the support plates (101) and the connecting plates (401).

5. The composite busbar type flexible capacitor according to claim 2, characterized in that: The busbar (2) comprises a positive busbar and a negative busbar, the connection plates (401) on the positive busbar and the negative busbar correspond to each other one by one, the two ends of the capacitor core (3) are respectively fixedly connected to the corresponding connection plates (401), and a plurality of elastic ropes (7) are sleeved on two capacitor cores (3) mounted on adjacent connection plates (401).

6. The composite busbar type flexible capacitor according to claim 5, characterized in that: The capacitor cores (3) installed on two adjacent connection plates (401) are arranged in a staggered manner, and the elastic rope (7) is sleeved on the closest one and / or two capacitor cores (3) on any capacitor core (3) and the adjacent connection plates (401).

7. The composite busbar type flexible capacitor according to claim 2, characterized in that: The connection plate (401) is provided with a plurality of welding holes (8) for welding to the capacitor core (3), and the welding holes (8) include a contact portion (801) and two bifurcated portions (802).

8. The composite busbar type flexible capacitor according to claim 7, characterized in that: The two bifurcated portions (802) are arranged in parallel, and an arc-shaped protrusion (803) is provided between the bifurcated portion (802) and the contact portion (801).

9. The composite busbar type flexible capacitor according to claim 7, characterized in that: The capacitor core (3) corresponds to a plurality of welding holes (8).

10. The composite busbar type flexible capacitor according to claim 7, characterized in that: The bifurcated portion (802) is arranged towards the top of the shell (1).

Images