A low inductance capacitor

Abstract

The utility model discloses a low inductance capacitor, which includes a capacitor core, a first busbar, a second busbar, an insulator and a filling resin; the first busbar draws out electricity from the capacitor core, and the first busbar has a first lead-out terminal; the second busbar draws out electricity from the capacitor core and is opposite to the first busbar, and the second busbar has a second lead-out terminal; the first lead-out terminal and the second lead-out terminal respectively include a first overlap region and a second overlap region that overlap each other, the first overlap region and the second overlap region both have a first surface facing each other and a second surface facing each other, the first surface and the second surface are both covered with an insulator, and the bottom end of the insulator is buried in the filling resin. While ensuring the performance of low inductance, the capacitor can increase the stacking area between the positive and negative electrodes and improve the bonding strength between the electrodes and the filling resin.

Description

Technical Field

[0001] The utility model relates to the technical field of capacitors, in particular to a low-inductance capacitor. Background Art

[0002] With the rapid development of power electronics technology, metallized film capacitors are increasingly used in industrial control, new energy, automotive electronics, rail transit, power grids and other fields. The failure safety requirements for electronic controls are also higher. Low-inductance capacitors can reduce the damage of voltage spikes to IGBTs, reduce system impedance and improve electronic control performance.

[0003] At present, the industry generally adopts the method of increasing the mutual stacking between the positive and negative electrode terminals to reduce the inductance between the positive and negative electrodes, such as Figure 1 As shown, however, there will be the following problems: since insulation needs to be ensured between the positive and negative electrodes and a certain distance needs to be maintained between the positive and negative electrodes, the stacking area between the positive and negative electrodes cannot be large enough; due to the stacking design, the width of the electrode terminal needs to be larger and wider, and the linear expansion coefficient of the metal is significantly different from the linear expansion coefficient of the capacitor filling glue, which brings the risk of cracking at the root of the terminal after temperature shock, resulting in the risk of moisture-proof failure of the product. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems in the above-mentioned technology to a certain extent. To this end, the purpose of the utility model is to provide a low inductance capacitor, which can increase the stacking area between the positive and negative electrodes and improve the bonding strength between the electrodes and the filling resin while ensuring the performance of low inductance.

[0005] To achieve the above object, the embodiment of the utility model provides a low inductance capacitor, which includes a capacitor core, a first busbar, a second busbar, an insulator and a filling resin;

[0006] The first busbar draws power from the capacitor core, and the first busbar has a first lead-out end;

[0007] The second busbar draws power from the capacitor core and is opposite to the first busbar, and the second busbar has a second lead-out end;

[0008] The first lead-out end and the second lead-out end respectively include a first overlapping area and a second overlapping area that overlap each other, and the first overlapping area and the second overlapping area both have first surfaces facing each other and second surfaces opposite each other, and the first surface and the second surface are both covered with the insulator, and the bottom end of the insulator is buried in the filling resin.

[0009] According to a low-inductance capacitor of an embodiment of the utility model, the first surface and the second surface of the overlapping area of ​​the first lead-out terminal and the second lead-out terminal are covered with an insulator, so that the stacking area can be increased, and the bottom end of the insulator is buried in the filling resin, which can wrap the roots of the positive and negative electrodes to ensure insulation and act as a connecting material between the electrode and the filling resin to improve the bonding strength.

[0010] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A three-dimensional diagram of a capacitor with closely fitting lead ends in the related art;

[0012] Figure 2 A three-dimensional diagram of a low-inductance capacitor according to an embodiment of the utility model;

[0013] Figure 3 A cross-sectional view of a low-inductance capacitor according to an embodiment of the present utility model;

[0014] Figure 4 It is a partial component diagram of a low-inductance capacitor involved in an embodiment of the utility model.

[0015] Description of labels:

[0016] The first busbar 100 , the first lead-out end 110 , the first overlap region 111 , the connection terminal portion 112 or 222 , the second busbar 200 , the second lead-out end 210 , the second overlap region 211 , the insulator 300 , the bottom end 301 , the clearance hole 302 , the filling resin 400 , and the housing 500 . DETAILED DESCRIPTION

[0017] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0018] The following is combined with Figure 2-Figure 4 The low-inductance capacitor according to the embodiment of the utility model is described in detail.

[0019] like Figure 3 As shown, the low inductance capacitor according to the embodiment of the present invention includes a capacitor core (not shown), a first bus bar 100 , a second bus bar 200 , an insulator 300 and a filling resin 400 .

[0020] Specifically, the first busbar 100 draws electricity from the capacitor core, and the first busbar 100 has a first lead-out end 110; the second busbar 200 draws electricity from the capacitor core and is opposite to the first busbar 100, and the second busbar 200 has a second lead-out end 210; the first lead-out end 110 and the second lead-out end 210 respectively include a first overlapping area 111 and a second overlapping area 211 that overlap each other; the first overlapping area 111 and the second overlapping area 211 both have a first surface a facing each other and a second surface b facing away from each other, and the first surface a and the second surface b are both covered with an insulator 300, and the bottom end 301 of the insulator 300 is buried in the filling resin 400.

[0021] That is to say, compared with Figure 1 In the related technology shown, the tightly fitted first lead-out end 110 and the second lead-out end 210 are provided with an insulator 300 only between the first surface a of the first overlapping area 111 and the second overlapping area 211. In the present application, the second surface b of the first overlapping area 111 and the second overlapping area 211 is also covered with an insulator 300, and the bottom end 301 of the insulator 300 is buried in the filling resin 400.

[0022] Therefore, according to a low inductance capacitor of an embodiment of the utility model, the stacking area can be increased by covering the first surface a and the second surface b of the overlapping area of ​​the first lead-out terminal 110 and the second lead-out terminal 210 with the insulator 300, and the bottom end 301 of the insulator 300 is buried in the filling resin 400, which can wrap the roots of the positive and negative electrodes to ensure insulation and act as a connecting material between the electrode and the filling resin 400 to improve the bonding strength.

[0023] The overlap of the first overlap region 111 and the second overlap region 211 can reduce inductance.

[0024] The above implementation is the most basic solution of this application, which can solve the problems raised in the background technology and achieve the purpose of this application. The following improves the above basic solution in many aspects to further improve its performance, thereby achieving better implementation effect.

[0025] Example

[0026] Combination Figure 1 and Figure 4In this embodiment, the insulator 300 covers the first surface a and bends and extends from the top of the first surface a to cover the second surface b until the bottom 301 of the insulator 300 is buried in the filling resin 400. In this way, for the root of the first lead-out terminal 110 and the second lead-out terminal 210, the insulator 300 is used to reverse the electrode position with insulation problems, increase the stacking area, and ensure the insulation performance between the two electrodes; and the insulator 300 wraps the root of the electrode to ensure insulation, and acts as a connecting material between the electrode and the filling resin 400 to improve the bonding strength.

[0027] More specifically, there are two insulators 300, which overlap each other between the two first surfaces a and cover the two first surfaces a one-to-one, and extend from the top ends of the two first surfaces a one-to-one to cover the two second surfaces b one-to-one. After covering the two second surfaces b, the ends of the insulators 300 are buried in the filling resin 400. It can be understood that in this embodiment, two insulators 300 are used to wrap and cover the overlapping areas of the two lead-out terminals respectively, so that the capacitor can increase the stacking area between the positive and negative electrodes while ensuring the performance of low inductance, and improve the bonding strength between the electrodes and the filling resin 400.

[0028] Furthermore, the insulator 300 may be made of materials such as insulating paper, insulating film, insulating glue or insulating plastic parts to cover the overlapping area.

[0029] In addition, the first lead-out end 110 and the second lead-out end 120 both have connection terminal portions 112 and 222 that can be connected to external accessories, and the insulator 300 has a clearance hole 302 for the connection terminal portions 112 and 222 to pass through; this can increase the insulator 300 to wrap the positive and negative electrodes.

[0030] The first overlap region 111 and the second overlap region 211 are both vertically arranged and centered on the filling resin 400, thereby ensuring that the overlap region can reduce inductance and also adapt the connection terminal portions 112 and 222 to be connected to external mating parts.

[0031] The other components of the capacitor of this embodiment adopt the structure of the prior art, such as two busbars connected with several capacitor cores, and separated by insulation in the overlapping area through the insulator 300 and then reversed, so as to assemble the two busbars, several capacitor cores and the insulator 300 into one, and complete the capacitor element assembly. The capacitor element assembly is then accommodated in the accommodating cavity of the shell 500, and then the filling resin 400 in the liquid phase state is injected into the accommodating cavity from the open mouth of the shell 500, so that the space between the capacitor element assembly and the shell 500 is filled with the filling resin 400, and the filling resin 400 needs to bury the bottom end 301 of the insulator 300; if the filling resin 400 is injected, the filling resin 400 in the shell 500 can be hardened, and the capacitor element assembly is fixed relative to the shell 500 by the hardened filling resin 400.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "several" is two or more, unless otherwise clearly and specifically defined.

[0034] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or several embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0037] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A low inductance capacitor, characterized in that: It includes a capacitor core, a first busbar, a second busbar, an insulator and a filling resin; The first busbar draws power from the capacitor core, and the first busbar has a first lead-out end; The second busbar draws power from the capacitor core and is opposite to the first busbar, and the second busbar has a second lead-out end; The first lead-out end and the second lead-out end respectively include a first overlapping area and a second overlapping area that overlap each other, and the first overlapping area and the second overlapping area both have first surfaces facing each other and second surfaces opposite each other, and the first surface and the second surface are both covered with the insulator, and the bottom end of the insulator is buried in the filling resin.

2. The low inductance capacitor according to claim 1, wherein: The insulator is fitted to cover the first surface and is bent and extended from the top of the first surface to fit to cover the second surface until the bottom of the insulator is buried in the filling resin.

3. The low inductance capacitor according to claim 1 or 2, characterized in that: There are two insulators, which overlap each other between the two first surfaces and cover the two first surfaces one by one, and are bent and extended from the top ends of the two first surfaces one by one to cover the two second surfaces one by one.

4. The low inductance capacitor according to claim 2, wherein: The first lead-out end and the second lead-out end each have a connection terminal portion that can be connected to an external mating component, and the insulator has a clearance hole for the connection terminal portion to pass through.

5. The low inductance capacitor according to claim 1, wherein: The insulator is insulating paper, insulating film, insulating glue or insulating plastic.

6. The low inductance capacitor according to claim 1, wherein: It also includes a shell, which accommodates the capacitor core, the first bus bar and the second bus bar; the filling resin is filled in the shell.

7. The low inductance capacitor according to claim 1, wherein: End surface electrodes are formed on both end surfaces of the capacitor core, the first bus bar is connected to one of the end surface electrodes, and the second bus bar is connected to the other end surface electrode.

8. The low inductance capacitor according to claim 1, wherein: The first overlapping area and the second overlapping area are both arranged upright along the vertical direction.

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