CN109524240B

CN109524240B - Pulse capacitor

Info

Publication number: CN109524240B
Application number: CN201811423942.5A
Authority: CN
Inventors: 贾华; 刘策; 魏劲容; 李龙; 庞博
Original assignee: Xi'an Xidian Electric Research Institute Co ltd; China XD Electric Co Ltd
Current assignee: Xi'an High Voltage Electrical Apparatus Research Institute Co.,Ltd.
Priority date: 2018-11-27
Filing date: 2018-11-27
Publication date: 2021-05-25
Anticipated expiration: 2038-11-27
Also published as: CN109524240A

Abstract

The present invention provides a pulse capacitor, comprising: at least one element wound coaxially; each of the elements comprises: the coaxial winding at least one first polar plate, at least one second polar plate and at least one insulating medium; the first polar plates and the second polar plates are alternately arranged, and the insulating medium is arranged between the adjacent first polar plates and the adjacent second polar plates; the first pole plates of each element are electrically connected together at one end of the element on a first side in the winding axial direction, and the second pole plates of each element are electrically connected together at one end of the element on a second side in the winding axial direction; the first side and the second side are different sides; the mutual electrical connection ends of two adjacent elements are located on the same side in the winding axial direction. The intrinsic inductance of the pulse capacitor can be reduced by the scheme.

Description

Pulse capacitor

Technical Field

The invention relates to the technical field of electric power, in particular to a pulse capacitor.

Background

The pulse capacitor is used as an energy storage element and widely applied to pulse power devices such as high-voltage or high-current tests, high-energy physics, strong impact light sources, laser technologies and the like. In some special fields, it is necessary to generate high-voltage pulses with a leading edge of only a few nanoseconds by using the cooperative work of a pulse capacitor and a fast switch.

The existing high-voltage pulse capacitor adopts a flattened film capacitor element, the size of the element and the serial and parallel connection number of the element are determined according to the capacity, and the high-voltage pulse capacitor is realized by connecting sheets and other modes, the inherent inductance of the high-voltage pulse capacitor is usually larger than 100nH due to the structural design, and the inductance of a relatively complex external loop such as a switch, a connecting line and the like is added, so that the inductance of the whole discharging loop is larger. Therefore, the discharge frequency of the loop formed by the inherent inductance and the capacitor is far lower than a required value, and the practical application requirement of fast discharge cannot be met.

Disclosure of Invention

The present invention provides a pulse capacitor to reduce the inherent inductance of the pulse capacitor.

In order to achieve the purpose, the invention adopts the following scheme:

in one embodiment of the invention, a pulse capacitor comprises: at least one element wound coaxially; each of the elements comprises: the coaxial winding at least one first polar plate, at least one second polar plate and at least one insulating medium; the first polar plates and the second polar plates are alternately arranged, and the insulating medium is arranged between the adjacent first polar plates and the adjacent second polar plates; the first pole plates of each element are electrically connected together at one end of the element on a first side in the winding axial direction, and the second pole plates of each element are electrically connected together at one end of the element on a second side in the winding axial direction; the first side and the second side are different sides; the mutual electrical connection ends of two adjacent elements are located on the same side in the winding axial direction.

In one embodiment of the invention, two adjacent elements are electrically connected by a non-inductive winding method.

In one embodiment of the invention, one end of the first polar plate, which is located at the second side, is recessed into a space between two adjacent insulating media inside and outside the first polar plate, and one end of the second polar plate, which is located at the first side, is recessed into a space between two adjacent insulating media inside and outside the second polar plate; one end of the first polar plate, which is positioned on the first side, extends out of a space between two adjacent insulating media inside and outside the first polar plate, and one end of the second polar plate, which is positioned on the second side, extends out of a space between two adjacent insulating media inside and outside the second polar plate; one end of each first polar plate of each element, which is positioned on the first side, is electrically connected together through tin-plated welding, and one end of each second polar plate of each element, which is positioned on the second side, is electrically connected together through tin-plated welding.

In one embodiment of the invention, in each of said elements, the number of said at least one first plate and the number of said at least one second plate are the same; the second plate of the element of an intermediate layer is electrically connected to the second plate of the element of a preceding layer of the intermediate layer, and the first plate of the element of the intermediate layer is electrically connected to the first plate of the element of a succeeding layer of the intermediate layer.

In one embodiment of the invention, a gasket is arranged between two adjacent elements, the gasket is recessed into the space between two adjacent insulating mediums inside and outside the gasket at the mutual electric connection end of the two adjacent elements, and the gasket extends out of the space between the two adjacent insulating mediums inside and outside the gasket at the opposite end of the mutual electric connection end of the two adjacent elements; and two adjacent elements are electrically connected through tin-plated welding.

In one embodiment of the present invention, the pulse capacitor further includes: an inner electrode, an outer electrode and a base; the base comprises a cylindrical structure and a disc structure formed by extending one end of the cylindrical structure outwards; the number of the at least one element is odd; the innermost electrode plate of the innermost element is electrically connected with the inner electrode; the outermost electrode plate of the outermost element is electrically connected with the outer electrode; the at least one element is sleeved on the cylindrical structure, the inner electrode is arranged at one end, far away from the disc structure, of the cylindrical structure, and the outer electrode is arranged at the outer edge area of the disc structure.

In one embodiment of the present invention, the pulse capacitor further includes: inner and outer connecting pieces; the inner electrode and the outer electrode are both annular; the inner connecting sheet is wound on the inner side of the innermost electrode plate of the innermost element and is matched with the annular inner electrode along the circumferential direction; the outer connecting sheet is wound on the outer side of the outermost pole plate of the outermost element and is matched with the annular outer electrode along the circumferential direction.

In one embodiment of the present invention, the pulse capacitor further includes: a hollow inner skeleton; the at least one element is coaxially wound on the hollow inner framework, and the hollow inner framework is sleeved on the cylindrical structure.

In one embodiment of the present invention, the outer peripheral side of the annular inner electrode is disposed in cooperation with the inner peripheral side of the inner connection piece; the annular outer electrode is provided with a groove along the circumferential direction, and one end of the outer connecting sheet, which is far away from the at least one element, is embedded and welded in the groove through tin coating.

In one embodiment of the invention, the cylindrical structure is a hollow cylindrical structure; the discharge switch is arranged in the hollow cylindrical structure and is respectively and electrically connected with the inner electrode and the outer electrode.

According to the pulse capacitor, the coaxial winding element and at least one first polar plate, at least one second polar plate and at least one insulating medium are adopted, so that the distance between the polar plates can be as close as possible. One side end of each first polar plate of each element is electrically connected together, the other side end of each second polar plate of each element is electrically connected together, the mutually electric connection ends of the two adjacent elements are positioned on the same side, and the length of a connecting line between the elements and between the polar plates can be shortened as far as possible.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts. In the drawings:

FIG. 1 is a schematic diagram of a partial longitudinal cross-sectional structure of a pulse capacitor according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a portion of the structure of one embodiment of the present invention;

FIG. 3 is a schematic diagram of a top view of a pulse capacitor according to an embodiment of the present invention;

fig. 4 is a schematic bottom view of a pulse capacitor according to an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.

Fig. 1 is a schematic diagram of a partial longitudinal cross-sectional structure of a pulse capacitor according to an embodiment of the present invention. As shown in fig. 1, the pulse capacitor of some embodiments may include: at least one element wound coaxially. Each of the elements may include: at least one first pole plate 4b1, at least one second pole plate 4b2, and at least one insulating medium 4a1, which are coaxially wound.

The first electrode plates 4b1 and the second electrode plates 4b2 are alternately arranged, and the insulating medium 4a1 is arranged between the adjacent first electrode plates 4b1 and the second electrode plates 4b 2. For example, the first electrode plate 4b1, the second electrode plate 4b2, and the insulating medium 4a1 therebetween, which are stacked in this order, may be wound around the first electrode plate 4b1 as the inner side, and may be wound several times, so that at least one first electrode plate 4b1, at least one second electrode plate 4b2, and the insulating medium 4a1 therebetween may be obtained. As shown in fig. 1, two adjacent elements may be separated by a spacer 4e or other insulating material.

The element may be a capacitor element, or an equivalent capacitor obtained by connecting a plurality of capacitors in series, parallel, or the like. The first plate 4b1 and the second plate 4b2 may be plates of a capacitor, and may be thin film type plates, for example, aluminum foil. The insulating medium 4a1 may be an electrical film, and may be used as a medium between the plates. The number of the first plate 4b1 and the second plate 4b2 may be one or more, and in actual production, may be several tens. The number of elements may be determined according to the parameter requirements of the pulse capacitor.

The number of first plates 4b1 in the elements of different layers may be different and the number of second plates 4b2 in the elements of different layers may be different. The first plate 4b1 and the second plate 4b2 preferably have the same number, in which case the winding area (or winding length in the case of the same width) of the elements of different layers (including the first plate 4b1, the second plate 4b2 and the insulating medium 4a1) can be the same, thereby making the electric field of the pulse capacitor more uniform.

The first pole plates 4b1 of each element are electrically connected together at one end of the element on a first side in the winding axial direction a, and the second pole plates 4b2 of each element are electrically connected together at one end of the element on a second side in the winding axial direction a, the first side and the second side being different sides. In the winding axial direction a, the element has two sides, for example, as shown in fig. 1, the first side may be an upper side of the element, the first pole plate 4b1, and the second pole plate 4b2, and the second side may be a lower side of the element, the first pole plate 4b1, and the second pole plate 4b 2. For example, the ends of the first plates 4b1 on the first side of the innermost (first) layer elements are electrically connected together via short leads 4c, and the ends of the second plates 4b2 on the second side of the innermost (first) layer elements are electrically connected together via long leads 4 d. In other embodiments, the first side may be the upper side of the element, the first plate 4b1 and the second plate 4b2, the second side may be located, and the lower side of the element, the first plate 4b1 and the second plate 4b2 may be the first side.

The mutual electrical connection ends of two adjacent elements are located on the same side in the winding axial direction. For example, the mutually electrically connecting ends between the elements of the first layer and the elements of the second layer are both located on the lower side in the winding axial direction a, and may be electrically connected together via the long lead 4d on the lower side; the mutually electrically connecting ends between the elements of the second layer and the elements of the third layer are both located on the upper side in the winding axial direction a, and can be electrically connected together via the long lead 4d on the upper side.

In this embodiment, the distance between the pole plates can be as close as possible by the coaxial winding element and at least one first pole plate, at least one second pole plate and at least one insulating medium therein. One side end of each first polar plate of each element is electrically connected together, the other side end of each second polar plate of each element is electrically connected together, the mutually electric connection ends of the two adjacent elements are positioned on the same side, and the length of a connecting line between the elements and between the polar plates can be shortened as far as possible.

In some embodiments, the element employs a non-inductive winding method. In this way, the mutual inductance generated by the current reversal of adjacent elements can be used to at least partially reduce the inherent inductance of core 4 (which may include all parts of the interior of housing 5), and the self-inductance of the element itself can be greatly reduced compared to the conventional method of inserting lead tabs into a pulse capacitor element.

In some embodiments, an end of the first pole plate 4b1 on the second side is recessed into a space between two adjacent inside and outside insulating mediums 4a1 of the first pole plate 4b1, and an end of the second pole plate 4b2 on the first side is recessed into a space between two adjacent inside and outside insulating mediums 4a1 of the second pole plate 4b 2. As shown in fig. 1, for example, the depth of the lower recession of the first plate 4b1 of each element may be 5 to 10 mm; the depth of the upper side recession of the second plate 4b2 of each element may be 5 to 10 mm.

One end of the first pole plate 4b1 on the first side extends out of the space between the two adjacent inside and outside insulating mediums 4a1 of the first pole plate 4b1, and one end of the second pole plate 4b2 on the second side extends out of the space between the two adjacent inside and outside insulating mediums 4a1 of the second pole plate 4b 2. As shown in FIG. 1, the first plate 4b1 of each element may protrude from the upper side by 3 to 5mm, for example.

The ends of the first pole plates 4b1 on the first side of each element are electrically connected together by tin-plated soldering, and the ends of the second pole plates 4b2 on the second side of each element are electrically connected together by tin-plated soldering. As shown in fig. 1, for example, the upper sides of the respective first electrode plates 4b1 of the elements of the first layer (innermost layer) are connected together by short leads 4c obtained by tin-plated soldering, and the lower sides of the respective second electrode plates 4b2 of the elements of the first layer (innermost layer) are connected together by long leads 4d obtained by tin-plated soldering; the upper sides of the first electrode plates 4b1 of the elements of the second layer are connected together by the upper long leads 4d obtained by tin-coating soldering, and the lower sides of the second electrode plates 4b2 of the elements of the second layer are connected together by the lower long leads 4d obtained by tin-coating soldering; the upper sides of the first electrode plates 4b1 of the elements of the third layer (outermost layer) are connected together by upper long leads 4d obtained by tin-coating soldering, and the lower sides of the second electrode plates 4b2 of the elements of the third layer (outermost layer) are connected together by lower short leads 4c obtained by tin-coating soldering.

In this embodiment, through with polar plate one end retraction insulating medium, the other end protrusion insulating medium, can be convenient for electrically couple together and not switch on with the second polar plate simultaneously first polar plate, be convenient for electrically couple together and not switch on with the first polar plate simultaneously with the second polar plate. The tin-coating welding of the projecting polar plate is relative to a lead sheet welding structure, and the inherent inductance generated by a connecting wire can be reduced.

In some embodiments, in each of said elements, the number of said at least one first plate 4b1 and the number of said at least one second plate 4b2 are the same, the same number of two plates, facilitating the formation of a capacitor directly opposite. The second plate 4b2 of the element of the middle layer is electrically connected with the second plate 4b2 of the element of the previous layer of the middle layer, and the first plate 4b1 of the element of the middle layer is electrically connected with the first plate 4b1 of the element of the next layer of the middle layer. The former layer, the intermediate layer and the latter layer are three layers which are continuously adjacent to each other, and there is no connection relationship between the innermost layer element and the former layer element, and there is no connection relationship between the outermost layer element and the latter layer element. As shown in fig. 1, for example, the second plate 4b2 of the element of the first layer (preceding layer) is electrically connected to the second plate 4b2 of the element of the second layer (intermediate layer), and the first plate 4b1 of the element of the second layer (intermediate layer) is electrically connected to the first plate 4b1 of the element of the third layer (succeeding layer).

In other embodiments, the positions of the first plate 4b1 and the second plate 4b2 can be interchanged, and the connection mode between the plates and the elements can be changed correspondingly.

In some embodiments, a gasket 4e is disposed between two adjacent elements, and the gasket 4e is recessed inside a space between two adjacent elements inside and outside the gasket 4e at the mutually electrically connecting end of the two adjacent elements, and the gasket 4e protrudes outside the space between two adjacent elements inside and outside the gasket 4e at the opposite end of the mutually electrically connecting end of the two adjacent elements; and two adjacent elements are electrically connected through tin-plated welding. As shown in fig. 1, for example, the mutually electrically connecting end of the element of the first layer and the element of the second layer is one end located on the lower side, and the opposite end of the mutually electrically connecting end is one end of the upper side of the element of the first layer and the element of the second layer. Specifically, for example, the lower end of the spacer 4e between the elements of the first layer and the elements of the second layer is recessed inside the adjacent two insulating media, and the upper end of the spacer 4e protrudes outside the two insulating media.

The spacer 4e may be made of an insulating material, for example, an electric film, and preferably, a relatively hard insulating material. In other embodiments, multiple layers of electrical films may be disposed on both the inner and outer sides of the spacer 4 e.

In this embodiment, the liner can serve as an isolation and barrier. The connection between two adjacent elements can be facilitated by the concave design of one end of the gasket. By extending the other end of the pad, it is convenient to isolate the parts of the two adjacent elements which should not be connected.

Fig. 2 is a sectional view of a part of the structure of an embodiment of the present invention. Referring to fig. 1 and 2, in some embodiments, the pulse capacitor may further include: inner electrode 2, outer electrode 3 and base 1. The base 1 may comprise a cylindrical structure 11 and a disc structure 12 formed by extending one end of the cylindrical structure 11 outwards. The cylindrical structure 11 may be solid or hollow and the disc structure 12 may be a full disc or a disc with an opening in the middle. The base 1 may be made of various insulating materials.

The number of the at least one element is odd. The innermost plate of the innermost element is electrically connected to the inner electrode 2; the outermost electrode plate of the outermost element is electrically connected to the external electrode 3; the at least one element is sleeved on the cylindrical structure, the inner electrode 2 is arranged at one end, far away from the disc structure, of the cylindrical structure, and the outer electrode 3 is arranged at the outer edge area of the disc structure.

The innermost plate, the outermost plate may be the first plate 4b1 or the second plate 4b 2. When the first polar plate in the innermost element is positioned at the inner side of the second polar plate, the innermost polar plate is the first polar plate; when the second plate in the innermost element is positioned on the inner side of the first plate, the innermost plate is the second plate. When the first polar plate in the outermost element is positioned at the outer side of the second polar plate, the outermost polar plate is the first polar plate; when the second polar plate in the outermost element is positioned outside the first polar plate, the outermost polar plate is the second polar plate. As shown in fig. 1, the innermost plate of the innermost (first) layer element is the first plate 4b1, and the outermost plate of the outermost (third) layer element is the second plate 4b 2.

In some embodiments, the pulse capacitor may further include: and the insulating shell 5 is matched with the base 1, the inner electrode 2 and the outer electrode 3 to form a closed space.

In some embodiments, the pulse capacitor may further include: an inner connecting piece 2a and an outer connecting piece 3 a. The inner electrode 2 and the outer electrode 3 may each be annular. The inner connecting piece 2a is wound around the inner side of the innermost plate of the innermost element and is circumferentially fitted with the annular inner electrode 2, for example, the outer diameter of the annular inner electrode 2 is equal to or close to the inner diameter of the inner connecting piece 2 a. The outer connecting sheet 3a is wound on the outer side of the outermost pole plate of the outermost element and is matched with the annular outer electrode 3 along the circumferential direction. For example, the inner diameter or the average radial dimension of the annular outer electrode 3 is equal to or close to the inner diameter of the outer web 3 a.

In this embodiment, in the case where the number of the components is odd, one end of the innermost component connected to the internal electrode and one end of the outermost component connected to the external electrode may be located at diagonal positions, thereby preventing adverse effects caused by too close positions of the internal electrode and the external electrode. The inner electrode and the outer electrode are annular and are respectively matched with the inner connecting sheet of the innermost element and the outer connecting sheet of the outermost element, so that the lead inductance of the element can be reduced.

In some embodiments, the pulse capacitor may further include: a hollow inner skeleton 6; the at least one element is coaxially wound on the hollow inner framework 6, and the hollow inner framework 6 is sleeved on the cylindrical structure. The hollow inner frame 6 may be, for example, a hollow thin-walled insulating circular tube. The first pole plate 4b1, the second pole plate 4b2, etc. are wound around the hollow inner frame 6, and the wound elements are fitted to the base 1, thereby facilitating assembly.

In some embodiments, the outer peripheral side of the ring-shaped inner electrode 2 is disposed in cooperation with the inner peripheral side of the inner connection piece 2 a; the annular outer electrode 3 is provided with a groove 31 along the circumferential direction, and one end of the outer connecting sheet 3a, which is far away from the at least one element, is embedded and welded in the groove through tin coating. As shown in fig. 1 and 2, the outer diameter of the inner electrode 2 having a ring shape may be equal to the inner diameter of the inner connection piece 2a, so as to facilitate connection. The internal electrode 2 and the internal connection sheet 2a can be closely attached to each other and can be connected by tin-plated welding. The outer electrode 3 may be embedded in a stepped annular notch provided in the edge region of the disc structure 12, and the upper surface and the side surface may be flush with the upper surface and the side surface of the disc structure 12. The width of the groove 31 may be 1-2 mm.

In some embodiments, as shown in FIG. 2, the cylindrical structure 11 may be a hollow cylindrical structure. The discharge switch is arranged inside the hollow cylindrical structure 11 and is respectively and electrically connected with the inner electrode 2 and the outer electrode 3.

In this embodiment, the discharge switch is placed in the internal space of the cylindrical structure in the middle of the capacitor, and the electrode of the discharge switch is directly contacted with the inner electrode and the outer electrode of the capacitor, which is beneficial to reducing the inductance of the outer loop.

Fig. 3 is a schematic top view of a pulse capacitor according to an embodiment of the invention. Fig. 4 is a schematic bottom view of a pulse capacitor according to an embodiment of the invention. As shown in fig. 1, 3 and 4, in some embodiments, at least one ring-shaped lead (e.g., long lead 4d) can be connected between two adjacent elements by tin-coating welding. The first plates 4b1 in each element can be tin-plated and soldered together by at least one ring-shaped lead (e.g., the upper short lead 4c or the upper long lead 4 d). The shape of the ring-shaped lead may be a fan shape. In the embodiment, the annular lead is tinned and welded, so that the contact is good, and the lead inductance is reduced.

In some embodiments, the pulse capacitor is a coaxial high voltage pulse capacitor with low intrinsic inductance, comprising a base 1, an inner electrode 2, an outer electrode 3, a core 4, an outer shell 5, and an inner skeleton 6. The base 1 is an insulator with an inverted T-shaped structure and consists of a disc at the bottom and a hollow cylinder in the middle. The inner electrode 2 is a special-shaped conductive ring, the inner diameter of the special-shaped conductive ring is the same as that of the hollow cylindrical part of the base 1, and the special-shaped conductive ring is arranged at the upper end of the hollow cylindrical part of the base 1. The outer electrode 3 is a conductive ring embedded in the disk part of the base 1, and the outer diameter of the conductive ring is the same as that of the disk part of the base 1; the upper surface of outer electrode 3 sets up annular groove, and the recess width is 1 ~ 2 mm. The shell 5 is a thin-wall hollow cylindrical insulator, the upper end of the shell is provided with a round hole, and the round hole is matched and contacted with the outer side of the inner electrode 2. The inner framework 6 is a hollow thin-wall insulating circular tube, and the inner surface of the inner framework is tightly matched with the outer surface of the hollow cylindrical part in the base 1. The core 4 is arranged in the closed space formed by the base 1, the inner electrode 2, the outer electrode 3 and the shell 5; the core 4 is wound with the inner frame 6 as a reel.

In some embodiments, core 4 is wound sequentially from inside to outside about element 1, element 2, element 42, element 3, element 43, …, element n; the element may comprise an electrical film 4a and two first 4b1 and second 4b2 plates made of aluminium foil. Preferably, a gasket 4e is arranged between the end of the 1 st element 41 and the start of the 2 nd element 42, the upper end of the gasket 4e extends 5-7 mm beyond the end of the electrical film 4a, and the lower end thereof is retracted 2-3 mm into the end of the electrical film 4 a; a gasket 4e is arranged between the end of the 2 nd element 42 and the start of the 3 rd element 43, the upper end of the gasket 4e is retracted into the end part of the electrical film 4a for 2-3 mm, and the lower end of the gasket 4e extends out of the end part of the electrical film 4a for 5-7 mm; …, and so on. Preferably, the upper end of the first polar plate 4b1 protrudes out of the electrical film 4a by 3-5 mm, and the lower end of the first polar plate is retracted into the electrical film 4a by 5-10 mm; the upper end of the second pole plate 4b2 is retracted into the electrical film 4a, the retraction depth is 5-10 mm, the lower end of the second pole plate protrudes out of the electrical film 4a, and the protruding length is 3-5 mm. Preferably, the inner connecting piece 2a is inserted into the first pole plate 4b1 and extends 3-5 mm beyond the end of the pole plate when the 1 st element 41 is wound for the first turn; the outer connecting piece 3a is inserted into the second pole piece 4b2 and extends 3-5 mm beyond the end of the pole piece when the nth element is wound for the last turn. Preferably, the contact surface of the protruding part of the inner connecting sheet 2a and the lower end of the inner electrode 2 is soldered by tin coating; the protruding portion of the external connection piece 3a is inserted into the annular groove of the external electrode 3 and filled with solder for soldering.

In some embodiments, intermittent annular short leads 4c are tin-plated between the inner connecting tab 2a and the first plate 4b1 of the 1 st element 41. Preferably, the second pole plate 4b2 of the 1 st element 41 and the second pole plate 4b2 of the 2 nd element 42 are soldered by intermittent annular long lead 4 d; the first pole plate 4b1 of the 2 nd element 42 and the first pole plate 4b1 of the 3 rd element 43 are connected by adopting an intermittent annular long lead 4d for tin coating welding; …, and so on. Preferably, the outer connecting sheet 3a and the second pole plate 4b2 of the nth element are soldered by intermittent annular short lead 4 c. Preferably, the number n of elements is preferably odd.

In order that those skilled in the art will better understand the present invention, embodiments of the present invention will be described below with reference to specific examples.

The pulse capacitor can be a coaxial high-voltage pulse capacitor with low inherent inductance, and a preferable structure, as shown in fig. 1 and 2, can comprise a base 1, an inner electrode 2, an outer electrode 3, a core 4 and an inner skeleton 6, and can also comprise an outer shell 5. The base 1 may be an insulator with an inverted "T" structure or a "T" structure, and may be composed of two parts, namely a disk structure 12 at the bottom and a hollow cylindrical structure 11 in the middle. The inner electrode 2 may be a specially shaped conductive ring having an inner diameter identical to that of the hollow cylindrical structure 11 of the base 1, and may be disposed at an upper end of the hollow cylindrical structure 11 of the base 1. The outer electrode 3 may be a conductive ring embedded in the disk structure 12 of the base 1, and has the same outer diameter as the disk structure 12 of the base 1. The upper surface of the outer electrode 3 can be provided with an annular groove 31, and the width of the groove 31 can be 1-2 mm. The shell 5 can be a thin-wall hollow cylindrical insulator, the upper end of the shell can be provided with a round hole, and the round hole is matched and contacted with the outer side of the inner electrode 2.

The inner frame 6 may be a hollow thin-walled insulating circular tube, the inner surface of which is tightly fitted with the outer surface of the hollow cylindrical structure 11 in the base 1.

The core 4 may be disposed in a closed space formed by the base 1, the inner electrode 2, the outer electrode 3, and the housing 5, wound with the inner frame 6 as a reel, and sequentially wound with the 1 st element 41, the 2 nd element 42, the 3 rd element 43, …, and the nth element from the inside to the outside. The value of n is determined according to the parameter requirement of the pulse capacitor.

The element is formed by winding an electrical film 4a and two aluminum foils (a first pole plate 4b1 and a second pole plate 4b2) as pole plates, wherein one end of the aluminum foil protrudes and the other end of the aluminum foil retracts. A spacer 4e may be provided between two adjacent elements to serve as an isolation and barrier in accordance with a potential difference between the elements. In the isolation position, the end of the gasket 4e can extend 5-7 mm out of the end of the electrical film, and the other end can be retracted 2-3 mm into the end of the electrical film, so that damage to the aluminum foil during tin-coating welding is avoided.

An inner connecting sheet 2a and an outer connecting sheet 3a may be respectively disposed outside the core 4, wherein the inner connecting sheet 2a is inserted into the first aluminum foil (the first polar plate 4b1) and extends 3-5 mm from the end of the first aluminum foil when the 1 st element 41 is wound for the first turn; the outer connecting piece 3a is inserted into the second aluminum foil (the second pole piece 4b2) and protrudes 3-5 mm beyond the end of the aluminum foil when the nth element is wound for the last turn.

In the implementation of the core 4, the inner frame 6 is used as a reel, the electrical film 4a is wound for a certain number of turns, then the aluminum foils (the first pole plate 4b1 and the second pole plate 4b2) are brought in, the inner connecting sheet 2a is inserted into the first aluminum foil (the first pole plate 4b1), the first element 41 is wound according to the set aluminum foil length, the aluminum foils (the first pole plate 4b1 and the second pole plate 4b2) are disconnected, the gasket 4e is inserted into the unbroken electrical film 4a, the aluminum foils (the first pole plate 4b1 and the second pole plate 4b2) are brought in again after two turns, the winding of the 2 nd element 42 is started, and then the operations are sequentially carried out until the nth element. When the nth element is wound for the last turn, the external connection piece 3a is inserted into the second aluminum foil (the second pole plate 4b2) and wound until the element is completed, the aluminum foils (the first pole plate 4b1 and the second pole plate 4b2) are cut off, the unbroken electrical film is continuously wound for two turns and then cut off, and the core 4 is fixed by the adhesive tape, thereby completing the winding of the core 4.

As shown in fig. 3 and 4, the inner connection tab 2a and the first aluminum foil (first electrode plate 4b1) of the 1 st element 41 are soldered by intermittent tin-coating with the annular short lead 4c, and the second aluminum foil (second electrode plate 4b2) of the 1 st element 41 and the second aluminum foil (second electrode plate 4b2) of the 2 nd element 42 are soldered by intermittent tin-coating with the annular long lead 4 d. As shown in fig. 4, the first aluminum foil (first plate 4b1) of the 2 nd element 42 and the first aluminum foil (first plate 4b1) of the 3 rd element 43 are soldered by means of intermittent ring-shaped long lead 4 d; and the outer connecting sheet 3a and the second aluminum foil (the second plate 4b2) of the nth element are subjected to tin-coating welding by adopting an intermittent annular short lead 4 c.

In the preferred embodiment, the wound core 4 with the inner frame 6 is inserted into the cylindrical structure 11 of the base 1, and the downward extension of the external connection piece 3a is inserted into the annular groove 31 of the external electrode 3, which can be filled with solder. The inner electrode 2 can be bonded to the upper end of the cylindrical structure 11 of the base 1 such that the upward extension of the inner connecting piece 2a contacts the arc surface of the lower end of the inner electrode 2, which can also be soldered by tin-coating. The outer shell 5 is bonded with the contact parts of the inner electrode 2 and the outer electrode 3, and the assembly of the whole capacitor is completed.

The pulse capacitor provided by the embodiment of the invention adopts the aluminum foil protruding non-inductive winding method, and compared with the traditional method for inserting the lead sheet into the pulse capacitor element, the self-inductance of the element can be greatly reduced; the series connection of the elements depends on the aluminum foil convex parts and adopts alternate welding, and the mutual inductance generated by the current reversal of the adjacent elements can partially offset the inherent inductance of the core; the head end of the first element and the tail end of the last element are provided with connecting pieces which are directly electrically connected with the inner electrode and the outer electrode of the capacitor, so that the lead inductance can be reduced. Further, the multilayer winding ensures that the voltage borne by a single element is not high, and ensures that the capacitor can work under a higher voltage condition; the radial electric field of the annularly wound core is uniformly distributed, so that the stability of the capacitor in operation is improved; the intermittent ring-shaped lead bonding is compatible with the reliability of the connection between the elements and the convenience of the vacuum impregnation of the core. Furthermore, a discharge switch can be placed in a cylindrical space in the middle of the capacitor, and an electrode of the discharge switch is directly contacted with an inner electrode and an outer electrode of the capacitor, so that the inductance of an outer loop is favorably reduced.

In the description herein, reference to the description of the terms "one embodiment," "a particular embodiment," "some embodiments," "for example," "an example," "a particular example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. The sequence of steps involved in the various embodiments is provided to schematically illustrate the practice of the invention, and the sequence of steps is not limited and can be suitably adjusted as desired.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A pulsed capacitor, comprising: at least one element wound coaxially; each of the elements comprises: the coaxial winding at least one first polar plate, at least one second polar plate and at least one insulating medium;

the first polar plates and the second polar plates are alternately arranged, and the insulating medium is arranged between the adjacent first polar plates and the adjacent second polar plates; the first pole plates of each element are electrically connected together at one end of the element on a first side in the winding axial direction, and the second pole plates of each element are electrically connected together at one end of the element on a second side in the winding axial direction; the first side and the second side are different sides; the mutual electric connection ends of two adjacent elements are positioned on the same side in the winding axial direction;

the element is wound by a non-inductive winding method;

in each of the elements, the number of the at least one first plate and the number of the at least one second plate are the same; the second plate of the element of an intermediate layer is electrically connected to the second plate of the element of a preceding layer of the intermediate layer, and the first plate of the element of the intermediate layer is electrically connected to the first plate of the element of a succeeding layer of the intermediate layer;

further comprising: an inner electrode, an outer electrode and a base; the base comprises a cylindrical structure and a disc structure formed by extending one end of the cylindrical structure outwards;

the number of the at least one element is odd; the innermost electrode plate of the innermost element is electrically connected with the inner electrode; the outermost electrode plate of the outermost element is electrically connected with the outer electrode; the at least one element is sleeved on the cylindrical structure, the inner electrode is arranged at one end, far away from the disc structure, of the cylindrical structure, and the outer electrode is arranged at the outer edge area of the disc structure.

2. The pulse capacitor of claim 1 wherein an end of said first plate on said second side is recessed into a space between two adjacent inner and outer insulating media of said first plate, and an end of said second plate on said first side is recessed into a space between two adjacent inner and outer insulating media of said second plate; one end of the first polar plate, which is positioned on the first side, extends out of a space between two adjacent insulating media inside and outside the first polar plate, and one end of the second polar plate, which is positioned on the second side, extends out of a space between two adjacent insulating media inside and outside the second polar plate; one end of each first polar plate of each element, which is positioned on the first side, is electrically connected together through tin-plated welding, and one end of each second polar plate of each element, which is positioned on the second side, is electrically connected together through tin-plated welding.

3. The pulse capacitor according to claim 1, wherein a spacer is provided between adjacent two of said members, and said spacer is recessed inside a space between two adjacent insulating media inside and outside of said spacer at mutually electrically connecting ends of adjacent two of said members, and said spacer is protruded outside the space between the two adjacent insulating media inside and outside of said spacer at an opposite end of the mutually electrically connecting ends of adjacent two of said members; and two adjacent elements are electrically connected through tin-plated welding.

4. The pulse capacitor of claim 1, further comprising: inner and outer connecting pieces;

the inner electrode and the outer electrode are both annular; the inner connecting sheet is wound on the inner side of the innermost electrode plate of the innermost element and is matched with the annular inner electrode along the circumferential direction; the outer connecting sheet is wound on the outer side of the outermost pole plate of the outermost element and is matched with the annular outer electrode along the circumferential direction.

5. The pulse capacitor of claim 1, further comprising: a hollow inner skeleton; the at least one element is coaxially wound on the hollow inner framework, and the hollow inner framework is sleeved on the cylindrical structure.

6. A pulse capacitor in accordance with claim 4, wherein an outer peripheral side of the inner electrode in a ring shape is disposed in cooperation with an inner peripheral side of the inner connection piece; the annular outer electrode is provided with a groove along the circumferential direction, and one end of the outer connecting sheet, which is far away from the at least one element, is embedded and welded in the groove through tin coating.

7. A pulse capacitor according to claim 1, wherein the cylindrical structure is a hollow cylindrical structure; the discharge switch is arranged in the hollow cylindrical structure and is respectively and electrically connected with the inner electrode and the outer electrode.