JP2006319027A - Low inductance capacitor - Google Patents

Abstract

A low-inductance capacitor capable of reducing wiring inductance and internal inductance with a simple configuration.
A plurality of capacitor elements 1 having electrodes 2 at both ends are arranged side by side, and element connecting portions 7 and 11 integrally provided on an electrode plate 15 having terminal portions 9 and 13 are electrodes of the capacitor element 1. 2 is connected. Element connection portions 7 and 11 are provided on a pair of opposite sides 6a, 6b, 10a, and 10b of the first electrode plate 4 and the second electrode plate 5 of the electrode plate 15, respectively. On both sides of the plurality of capacitor elements 1, the element connection portions 7 of the first electrode plate 4 and the element connection portions 11 of the second electrode plate 5 are alternately connected to the plurality of electrodes 2 arranged on the same side. The terminal portions 9 and 13 provided on the first electrode plate 4 and the second electrode plate 5 are arranged on the same side where one of the element connection portions 7 and 11 of the first electrode plate 4 and the second electrode plate 5 is disposed. Project in the direction.
[Selection] Figure 1

Description

  The present invention relates to a low inductance capacitor in which a plurality of capacitor elements and electrode plates are connected.

  Conventionally, electrolytic capacitors have been used as smoothing capacitors used in filter circuits and inverters. On the other hand, since the equivalent series inductance (ESL) and equivalent series resistance (ESR) of a film capacitor are smaller than that of an electrolytic capacitor and its life is long, in recent years, there has been a partial shift from an electrolytic capacitor to a film capacitor as a smoothing capacitor. Progressing. When the capacity required for smoothing increases, the inductance of the wiring connecting the elements also increases, and the smoothing function may be impaired.

And there exists a connection structure for making the inductance of wiring small (for example, refer to patent documents 1). That is, the capacitor (smoothing capacitor) described in Patent Document 1 includes a plurality of unit capacitors 51... And conductors that connect the positive terminal 52 and the negative terminal 53 of the unit capacitor 51, respectively, as shown in FIG. 54, 55. An insulator 56 is interposed between the positive electrode side conductor 54 and the negative electrode side conductor 55.
Japanese Utility Model Publication No. 62-2232

  However, even the one described in Patent Document 1 described above is difficult to reduce the internal inductance of the capacitor element because the directions of the currents flowing through the capacitor element (unit capacitor 51) are all the same direction.

  The present invention has been made to solve the above-described conventional drawbacks, and an object of the present invention is to provide a low-inductance capacitor capable of reducing wiring inductance and internal inductance with a simple configuration.

  The low-inductance capacitor according to claim 1 is provided integrally with an electrode plate 15 having terminal portions 9 and 13 connected to the outside by arranging a plurality of capacitor elements 1... Having electrodes 2 and 2 at both ends. The connected element connection portions 7 and 11 are low inductance capacitors connected to the electrodes 2 of the capacitor elements 1..., Respectively, and the electrode plate 15 is disposed in close proximity via an insulator 16. The first electrode plate 4 and the second electrode plate 5 are provided, and a plurality of element connecting portions 7... Are provided on a pair of opposite sides 6 a, 6 b, 10 a, 10 b of the first electrode plate 4 and the second electrode plate 5. .., 11... Are provided, and on both sides of the plurality of capacitor elements 1..., The element connection portions 7 and the second electrode plates of the first electrode plate 4 are connected to the plurality of electrodes 2. 5 element connection portions 11 are alternately connected, and the first Each of the terminal portions 9 and 13 provided on the electrode plate 4 and the second electrode plate 5 is provided with one element connecting portion 7... 11 of the first electrode plate 4 and the second electrode plate 5. It is characterized by protruding outward on the same side.

  The low-inductance capacitor according to claim 2 is characterized in that the plurality of capacitor elements 1 and the electrode plate 15 are accommodated in a case 21 and filled with a resin 22.

  The low-inductance capacitor according to claim 3 is characterized in that a fixing means 17 for fixing the first electrode plate 4 and the second electrode plate 5 to each other is provided.

  A low-inductance capacitor according to a fourth aspect of the present invention is provided integrally with an electrode plate 40 having terminal portions 35 and 38 connected to the outside by arranging a plurality of capacitors 27... Having terminals 29 and 30 at both ends. The connection portions 34 and 37 are low inductance capacitors respectively connected to the capacitors 27..., And the electrode plate 40 is connected to the first electrode plate 31 and the first electrode plate 31 disposed close to each other through an insulator 41. Provided with two electrode plates 32, provided with a plurality of connecting portions 34, 37,... On a pair of sides 33a, 33b, 36a, 36b opposite to each of the first electrode plate 31 and the second electrode plate 32; On both sides of the plurality of capacitors 27..., A connection portion 34 of the first electrode plate 31 and a connection portion 37 of the second electrode plate 32 are connected to the plurality of terminals 29. Connected alternately and above The terminal portions 35 and 38 provided on the first electrode plate 31 and the second electrode plate 32 are arranged with one connection portion 34 ···, 37 ··· of the first electrode plate 31 and the second electrode plate 32, respectively. It is characterized by projecting outward on the same side.

  According to the low inductance capacitor of the first aspect, in the adjacent capacitor element, the positive electrode and the negative electrode are alternately arranged, and the current flowing through the adjacent capacitor element is in the reverse direction, and the internal generated in the capacitor element. Inductance can be reduced. In addition, the current flowing through the electrode plate and the element connecting portion is in the reverse direction, and the wiring inductance at the electrode plate and the element connecting portion can be reduced.

  According to the low inductance capacitor of the second aspect, since the plurality of capacitor elements and the electrode plates are accommodated in the case and filled with the resin, the first electrode plate and the second electrode plate can be stably fixed, Excellent.

  According to the low inductance capacitor of the third aspect, since the fixing means for fixing the first electrode plate and the second electrode plate to each other is provided, the strength is excellent. In particular, if the capacitor element and the electrode plate are housed in a case and filled with resin, the electrode is used when a large current flows through the first electrode plate and the second electrode plate or when the electrode plate receives thermal stress. It is possible to prevent peeling from the resin surface of the plate and cracks in the resin.

  According to the low inductance capacitor of the fourth aspect, in the adjacent capacitor, the positive electrode and the negative electrode are alternately arranged, the current flowing through the adjacent capacitor is reversed, and the internal inductance generated in the capacitor is reduced. it can. Further, the current flowing through the electrode plate and the connecting portion is in the reverse direction, and the wiring inductance at the electrode plate and the connecting portion can be reduced.

  Next, specific embodiments of the capacitor of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a simplified cross-sectional front view of the low-inductance capacitor of the present invention, and FIG. 2 shows a simplified plan view thereof. This low-inductance capacitor includes a plurality of capacitor elements 1... And a pair of electrode plates 4 and 5 connected to the metallicon electrodes 2. The capacitor element 1 includes a main body 3 formed by winding a metallized plastic film, and electrodes (metallicon electrodes) 2 and 2 formed on both end surfaces of the main body 3.

  As shown in FIG. 3, one electrode plate (first electrode plate) 4 includes a flat plate-like main body portion 6 and element connection portions 7 (provided on a pair of opposite sides 6a and 6b of the main body portion 6). 7A) and 7 (7B), and a terminal portion 9 projecting from the one side 6a in the vicinity of the element connecting portion 7 (7A) on one side 6a. Each of the element connecting portions 7 and 7 includes a base portion 8a and 8a, and projecting piece portions 8b and 8b that protrude in a direction orthogonal to the main body portion 6 from the base portions 8a and 8a. The terminal portion 9 includes a first piece 9a that protrudes in a direction orthogonal to the main body portion 6 from the side 6a, and a second piece 9b that protrudes in parallel to the main body portion 6 from the first piece 9a. Become.

  As shown in FIG. 4, the other electrode plate (second electrode plate) 5 includes a flat plate-like main body 10 and element connection portions 11 (provided on a pair of opposite sides 10 a and 10 b of the main body 10). 11A) and 11 (11B), and a terminal portion 13 protruding from the one side 10a adjacent to the element connecting portion 11 (11A) of the one side 10a. Each of the element connecting portions 11 and 11 includes a base portion 12a and 12a, and projecting piece portions 12b and 12b that protrude in a direction orthogonal to the main body portion 10 from the base portions 12a and 12a. The terminal portion 13 includes a first piece 13a that protrudes in a direction orthogonal to the main body portion 10 from the side 10a, and a second piece 13b that protrudes in parallel to the main body portion 6 from the first piece 13a. Become.

  And each capacitor | condenser element 1 ... is arrange | positioned so that one metallicon electrode 2 ... may face the same direction, and the electrode plate 15 which has the 1st electrode plate 4 and the 2nd electrode plate 5 is attached to each capacitor | condenser element. 1 is arranged in parallel with each capacitor element 1 on the side surface side. The first electrode plate 4 and the second electrode plate 5 are arranged with an insulating sheet as the insulator 16 interposed therebetween. At this time, the first electrode plate 4 and the second electrode plate 5 are connected to each other via the fixing means 17. The fixing means 17 in this case can be constituted by an insulating bolt member 18 and an insulating nut member 19 that is screwed to the bolt member 18. That is, a through hole is provided in each of the first electrode plate 4, the second electrode plate 5, and the insulating sheet 16, and the first electrode plate 4, the second electrode plate 5, and the insulating sheet 16 have the same axial center. The bolt member 18 is inserted from the outside on the second electrode plate 5 side, and the nut member 19 is screwed onto the insulating screw shaft portion 18a of the bolt member 18 protruding from the first electrode plate 4, thereby The electrode plate 4 and the second electrode plate 5 are fixed. An insulating nut member 20 that functions as an anchor is screwed onto the screw shaft portion 18a. In this case, the fixing means 17 is disposed at four corners of the electrode plate 15 as shown in FIG.

  The terminal connection portions 7 and 7 of the first electrode plate 4 and the terminal connection portions 11 and 11 of the second electrode plate 5 are alternately connected. That is, the first terminal connection portion 7A of the first electrode plate 4 is connected to the first metallicon electrode 2A of the first capacitor element 1A, and the second terminal connection portion 7B of the first electrode plate 4 is connected to the second capacitor element 1B. To the second metallicon electrode 2B. Further, the first terminal connection portion 11A of the second electrode plate 5 is connected to the first metallicon electrode 2A of the second capacitor element 1B, and the second terminal connection portion 11B of the second electrode plate 5 is connected to the first capacitor element 1A. To the second metallicon electrode 2B.

  A plurality of capacitor elements 1..., Electrode plates 15, etc. are housed in a case 21, and resin 22 (for example, epoxy resin) is filled in the case 21. Thereby, a low inductance capacitor is completed. At this time, as shown in FIG. 1, the terminal portion 9 of the first electrode plate 4 and the terminal portion 13 of the second electrode plate 5 are the same in which the element connection portions 7A and 11A are arranged as terminals for connection to the outside. Projecting outwardly from the opening 21a of the case 21 on the side.

  In the low-inductance capacitor, the positive and negative electrodes are alternately arranged in the adjacent capacitor elements 1 and 1, and the current flowing through the adjacent capacitor elements 1 and 1 is in the opposite direction. Thereby, the internal inductance generated in the capacitor element 1 can be reduced. Further, the currents flowing through the electrode plates 4 and 5 and the element connection portions 7 and 11 are in the opposite directions, and the wiring inductance at the electrode plates and the element connection portions can be reduced.

  Further, since the electrode plates 4 and 5 are fixed by the fixing means 17 (the bolt member 18 and the nut members 19 and 20) and these are embedded in the resin 22, the electrode plates 4 and 5 can be firmly fixed. it can. For this reason, when a large current flows through the electrode plates 4 and 5 or when the electrode plates 4 and 5 are subjected to thermal stress, peeling from the resin surface of the electrode plates 4 and 5 and cracks in the resin 22 occur. Can be prevented.

  The configuration of the low-inductance capacitor is an effective connection structure even when the capacitor elements 1 having large dimensions are arranged in parallel. For example, the capacitance is 200 μF to 4000 μF, and the conventional 100 nH is about 10 nH to 50 nH. ESL can be made.

  Next, FIG. 5 and FIG. 6 show other embodiments, and in this case, four capacitor elements 1 are provided. That is, the first electrode plate 4 is provided with a first element connection portion 7A, a second element connection portion 7B, a third element connection portion 7C, and a fourth element connection portion 7D. A first element connection portion 11A, a second element connection portion 11B, a third element connection portion 11C, and a fourth element connection portion 11D are provided. In this case, in the first electrode plate 4, the first element connection portion 7A and the third element connection portion 7C are provided on the second side 6b side, and the second element connection portion 7B and the fourth element connection portion 7D are provided in the first electrode plate 4. Provided on the side 6a side. In the second electrode plate 5, the first element connection portion 11A and the third element connection portion 11C are provided on the first side 10a side, and the second element connection portion 11B and the fourth element connection portion 11D are the second. Provided on the side 10b side. Further, terminal portions 9 and 13 are provided on the first electrode plate 4 and the second electrode plate 5, respectively.

  Even in this case, the insulating sheet 16 is interposed between the first electrode plate 4 and the second electrode plate 5 and is fixed by the fixing means 17 as in FIG. Then, the first terminal connection portion 7A of the first electrode plate 4 is connected to the second metallicon electrode 2B of the first capacitor element 1A, and the second terminal connection portion 7B of the first electrode plate 4 is connected to the second capacitor element 1B. The first metallicon electrode 2A, the third terminal connection portion 7C of the first electrode plate 4 is connected to the second metallicon electrode 2B of the third capacitor element 1C, and the fourth terminal connection portion of the first electrode plate 4 is connected. 7D is connected to the first metallicon electrode 2A of the fourth capacitor element 1D. Further, the first terminal connection portion 11A of the second electrode plate 5 is connected to the first metallicon electrode 2A of the first capacitor element 1A, and the second terminal connection portion 11B of the second electrode plate 5 is connected to the second capacitor element 1B. To the second metallicon electrode 2B, the third terminal connection portion 11C of the second electrode plate 5 is connected to the first metallicon electrode 2A of the third capacitor element 1C, and the fourth terminal connection portion of the second electrode plate 5 is connected. 11D is connected to the second metallicon electrode 2B of the fourth capacitor element 1D. In this case, as shown in FIG. 6, the fixing means 17 is disposed at six locations including the four corner portions of the electrode plate 15 and the central portions of the pair of long sides 15 a and 15 b.

  A plurality of capacitor elements 1..., Electrode plates 15, and the like are housed in a case 21 and resin 22 is filled in the case 21. As a result, a low-inductance capacitor including four capacitor elements 1 is completed. At this time, as shown in FIG. 5, the terminal portion 9 of the first electrode plate 4 and the terminal portion 13 of the second electrode plate 5 serve as connecting terminals to the outside, and the connecting portions 7B, 7D, 11A, and 11C Projects outward from the case 21 on the same side where it is placed.

  For this reason, in the low inductance capacitors shown in FIGS. 5 and 6, the positive and negative electrodes are alternately arranged in the adjacent capacitor elements 1..., And the current flowing through the adjacent capacitor elements 1. In the opposite direction, and the internal inductance generated in the capacitor element 1 can be reduced. Further, the currents flowing through the electrode plates 4 and 5 and the element connection portions 7 and 11 are in the reverse direction, and the wiring inductance at the electrode plates 4 and 5 and the element connection portions 7 and 11 can be reduced. In addition, when a large current flows through the electrode plates 4 and 5 and when the electrode plates 4 and 5 are subjected to thermal stress, peeling from the resin surface of the electrode plates 4 and 5 and cracking of the resin can be prevented. .

  Incidentally, as shown in FIG. 9, the capacitor element 1 (not shown) may be housed in a case 25 and a capacitor 27 in which the case 25 is filled with a resin 26 (for example, epoxy resin) may be used. . That is, the capacitor 27 includes a main body 28 in which the capacitor element 1 is accommodated in the case 25 and filled with the resin 26, and a pair of terminals 29 and 30 protruding from the main body 28. The terminals 29 and 30 are provided with through holes 45 and 45 for fixing. A plurality of capacitors 27... Are connected to the electrode plates 31 and 32.

  That is, as shown in FIGS. 7 and 8, the first electrode plate 31 includes a flat plate-like main body portion 33 and a connection portion 34 (34A) provided on a pair of opposite sides 33a and 33b of the main body portion 33. , 34 (34B), and a terminal portion 35 protruding from the one side 33a adjacent to the connecting portion 34 (34A) of the one side 33a. The second electrode plate 32 includes a plate-like main body portion 36, connection portions 37 (37A) and 37 (37B) provided on a pair of opposite sides 36a and 36b of the main body portion 36, and one side. A terminal portion 38 projecting from one side 36a adjacent to the connecting portion 37 (37A) of 36a. The connecting portions 34 and 37 are provided with through holes 46 and 47 for fixing.

  An insulator (insulating sheet) 41 is interposed between the first electrode plate 31 and the second electrode plate 32. That is, the first electrode plate 31 and the second electrode plate 32 are brought close to each other through the insulator 41, thereby forming the electrode plate 40. Further, the first electrode plate 31 and the second electrode plate 32 are fixed via fixing means 17 that is a bolt-nut connection, similarly to the low-inductance capacitor shown in FIG.

  In this case, the first connection portion 34A of the first electrode plate 31 is connected to the first terminal 29 of the first capacitor 27A, and the second connection portion 34B of the first electrode plate 31 is connected to the second terminal 30 of the second capacitor 27B. Connecting. Further, the first connection portion 37A of the second electrode plate 32 is connected to the first terminal 29 of the second capacitor 27B, and the second connection portion 37B of the second electrode plate 32 is connected to the second terminal 30 of the first capacitor 27A. To do. Each connection portion 34A is connected to the terminals 29, 30 by screwing into the through holes 45, 45 of the terminals 29, 30 and the bolt members 42 inserted into the through holes 46, 47 of the connection portions 34, 37. It can be performed by the fixing means 44 comprising the nut member 43 to be performed.

  In the low inductance capacitors as shown in FIGS. 7 and 8, the positive and negative electrodes are alternately arranged in the adjacent capacitors 27 and 27, and the current flowing in the adjacent capacitors 27 and 27 is reversed. The internal inductance generated by the capacitors 27 and 27 can be reduced. Further, the currents flowing through the electrode plates 31 and 32 and the connection portions 34 and 37 are in the reverse direction, and the wiring inductance at the electrode plates 31 and 32 and the connection portions 34 and 37 can be reduced.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention. For example, the capacitor element 1 is not limited to a wound type, and may be a laminated film capacitor element. Further, in the low-inductance capacitor shown in FIGS. 1 and 5, etc., an insulating sheet is not disposed between the capacitor elements 1... It may be what you did. The fixing means 17 for fixing the electrode plates 4 and 5 does not use a bolt-nut connection, but sandwiches the electrode plates 4 and 5 with a U-shaped member or other soldering. Such fixing means may be used. Further, the number of capacitor elements 1 and capacitors 27 can be increased or decreased. Note that the resins 22 and 26 are not limited to epoxy resins, and even thermoplastic resins such as other urethane resins can be used.

1 is a simplified sectional front view showing an embodiment of a low inductance capacitor of the present invention. It is a simplified top view of the said low inductance capacitor. It is a top view of the 1st electrode plate of the said low inductance capacitor. It is a top view of the 2nd electrode plate of the said low inductance capacitor. It is a simplified cross-sectional front view which shows other embodiment of the low inductance capacitor | condenser of this invention. It is a simplified top view of the said low inductance capacitor. It is a simplified cross-sectional front view which shows another embodiment of the low inductance capacitor | condenser of this invention. It is a simplified top view of the said low inductance capacitor. It is a perspective view of the capacitor | condenser used for the said low inductance capacitor | condenser. It is a simplified top view of the conventional smoothing capacitor.

Explanation of symbols

  1 .. Capacitor element, 2 .. Metallicon electrode, 4 .. First electrode plate, 5... Second electrode plate, 6 a, 6 b .. Side, 7 .. Element connection portion, 9. 10b..Side, 11..Element connection portion, 13..Terminal portion, 15..Electrode plate, 16..Insulator, 17..Fixing means, 21..Case, 22..Resin, 27..Capacitor , 29, 30 ... Terminal, 31 ... First electrode plate, 32 ... Second electrode plate, 34, 37 ... Connection part, 35, 38 ... Terminal part

Claims (4)

  A plurality of capacitor elements (1...) Having electrodes (2) and (2) at both ends are juxtaposed and integrated with an electrode plate (15) having terminal portions (9) and (13) connected to the outside. The provided element connecting portions (7) and (11) are low inductance capacitors respectively connected to the electrodes (2...) Of the capacitor elements (1...), And the electrode plate (15) is an insulator. (16) provided with a first electrode plate (4) and a second electrode plate (5) which are disposed close to each other, and each of the first electrode plate (4) and the second electrode plate (5) A plurality of element connection portions (7...) (11...) Are provided on a pair of facing sides (6a) (6b) (10a) (10b), and on both sides of the plurality of capacitor elements (1. The plurality of electrodes (2...) Arranged on the same side are connected to the element connecting portion (7) of the first electrode plate (4) and the second electrode. The terminal portions (9) and (13) provided on the first electrode plate (4) and the second electrode plate (5) are alternately connected to the element connection portions (11) of (5), and The first electrode plate (4) and the second electrode plate (5) protrude outwardly on the same side where one element connecting portion (7...) (11...) Is disposed. Inductance capacitor.   2. The low inductance capacitor according to claim 1, wherein the plurality of capacitor elements (1) and the electrode plate (15) are accommodated in a case (21) and filled with resin.   The low-inductance capacitor according to claim 1 or 2, further comprising fixing means (17) for fixing the first electrode plate (4) and the second electrode plate (5) to each other.   A plurality of capacitors (27...) Having terminals (29) and (30) at both ends are provided side by side, and are integrally provided on an electrode plate (40) having terminal portions (35) and (38) connected to the outside. The connected portions (34) and (37) are low-inductance capacitors respectively connected to the capacitors (27,...), And the electrode plate (40) is arranged close to each other through an insulator (41). A first electrode plate (31) and a second electrode plate (32) are provided, and a pair of sides (33a) (33b) facing each of the first electrode plate (31) and the second electrode plate (32). ) (36a) (36b) are provided with a plurality of connecting portions (34...) (37...), And on both sides of the plurality of capacitors (27...), A plurality of terminals (29 · · · (30 · ·), the connection portion (34) of the first electrode plate (31) and the first The terminal portions (35) and (38) provided on the first electrode plate (31) and the second electrode plate (32) are alternately connected to the connection portions (37) of the electrode plate (32). The first electrode plate (31) and the second electrode plate (32) are projected outwardly on the same side where the connecting portions (34...) (37...) Are arranged. Low inductance capacitor.