FR2464546A1 - CAPACITOR WITH MICRO-BAND CONNECTIONS - Google Patents

Abstract

CAPACITOR EQUIPPED WITH A WINDING OF CONDENSER 3 WHOSE ANODE 9 AND CATHODE 11 SHEETS ARE CONNECTED TO EXTERNAL TERMINALS 23 AND 25 BY A NUMBER OF FLEXIBLE MICROBANDS 13 AND 15. THANKS TO THESE MICROBAND CONNECTIONS , WE OBTAIN A CAPACITOR HAVING A RELATIVELY LOW EQUIVALENT SERIAL IMPEDANCE FOR FREQUENCIES GREATER THAN THE RESONANCE FREQUENCY. APPLICATION: ELECTROLYTIC AND NON-ELECTROLYTIC COIL CAPACITORS.

Description

"Condenser with micro-band connections"

  The invention relates to a capacitor comprising

  both a capacitor winding that is in a

  housing closed by a cover, and a sheet of

  node as well as a cathode sheet are connected to at least two external terminals by a number of internal connection strips distributed along the length

leaves.

  In a known capacitor of the type specified in the preamble (of Philips manufacture, type 2222 1066 as described in the publication "Philips Technical Information" of September 22, 1975, page 5), the connecting strips connected to the anode sheet are situate

  side of the capacitor winding, while the

  connecting wires connected to the cathode foil

  located on the other side of the capacitor winding.

  As the connecting lamellae lying on one side of the capacitor winding and connected at intervals

  equal to the anode sheet, shun the lamellae of

  on the other side of the winding.

  denser and connected at equal intervals (in the direction of the length of the sheets) to the cathode sheet,

  obtained a consender whose impedance series called equi-

valente is relatively low.

  A known disadvantage of the capacitor is that, in high frequency applications, the value

  equivalent series impedance is even greater than

  above the desired level. This is essentially due to the component of the equivalent series impedance, component

  which is formed by the equivalent series inductance.

  The object of the invention is to provide a condensation

  the equivalent series inductance - and therefore equal

  the equivalent series impedance - only increases

  relatively low speed even for high frequencies

Vees.

  For this purpose, a capacitor according to the

  The invention is characterized in that the internal connection strips comprise electric micro-bands, which are each formed by two conductive flexible strips.

  electricity, separated from each other by an

  an electrically insulating one, while one of the two conducting lamellae belonging to the same micro-band is connected to the anode sheet of the winding of

  denser, and that the other is connected to the sheet of

  thode of the capacitor winding and this to a

  right contiguous to the common point of the conductive lamella

  concerned and the anode sheet.

  It should be noted that US Patents Nos. 3,654,524 and 3,611,051 recommend capacitors having a connection which is realized in the form of

  microstrip. Such a capacitor is realized by

  a number of flattened capacitor windings. Between two of the capacitor windings in the stack, the long flanges of two L-shaped metal sections are passed, which are separated from each other by an electrically insulating layer. By route

  welding, these L-shaped sections are connected to each winding

  capacitor and constitute a microstrip-shaped connection. Since the two L-shaped sections must be fixed by welding to the anode foil and the cathode foil inside the capacitor winding stack, it is necessary to make the ratio of leaf widths and the distance over which the leaves overlap. As a result, only a relatively small volume of the capacitor winding stack produces an effect

  capacity trainer. In such a capacitor, the

  pacity per unit volume is therefore relatively low.

  In theory, in a capacitor according to the invention, the distance over which the anode sheet

  and the cathode sheet overlap may be maximum.

  In practice, however, there is a slight departure from this

  mum, to minimize the risk of short-circuits occurring at the end faces of the capacitor winding.

  The following description, next to the drawing

  annexed, all given as an example, will make a good

  take as the invention can be realized.

  FIG. 1 represents a side view of a first embodiment of a conforming capacitor

to the invention.

  Figure 2 shows a plan view of the

densifier of Figure 1.

  Figure 3 shows on an enlarged scale a

  section along the line III-III of Figure 2.

  Figure 4 shows on an enlarged scale a

  section along the line IV-IV of Figure 1.

  Figure 5 shows a side view of

  partly in longitudinal section of a second mode of

  realization of a capacitor according to the invention.

  Figure 6 shows a section following the

line VI-VI of FIG.

  Figure 7 shows schematically the half

  cro-bands provided in a capacitor according to the in-

vention.

  Figure 8 shows a graph of the

  equivalent series and series resistance

  depending on the frequency, for a condensation

according to Figure 1.

  Figure 9 shows a graph of the

  equivalent series and series resistance

  depending on the frequency, for a condensation

  of the type according to Figure 1, comprising this

  two connections on the anode sheet and two

nexions on the cathode sheet.

  Figure 10 is a graph of the

  equivalent series pedance and series resistance equi-

  valent depending on the frequency for a capacitor

  comparable, with two con-

  naked on the anode sheet and two type connections

known on the cathode sheet.

  Figure II represents a graph of the

  equivalent series pedance and series resistance equi-

  valent depending on the frequency for a capacitor

according to Figure 5.

  The first embodiment of a condensation

  according to the invention, an illustrative embodiment

  trés by Figures 1 to 4, comprises a winding of

  capacitor 3 of a kind known per se, winding

  This type of capacitor winding consists of, for example, a shaped aluminum anode sheet, a first paper separator sheet, an aluminum cathode sheet, and a second foil sheet which can be

  soaked with an electrolytic liquid. Although the invention

  described with reference to an electronic capacitor.

  lythic, it does not restrict itself to it, and in fact applies to all so-called coiled capacitors. The casing 1 is closed by a cover 5 consisting of an electrically insulating material, such as for example a type of hard rubber. In a common way, the capacitor

  coil 3 is fixed in the casing 1 by means of a cannula

  7. By means of four slats of con-

  flexible metal nipples 13 and 15, the anode sheet

  9 as well as the cathode sheet Il of the winding

  3 of capacitor 3 (see FIG. 3) are connected in this order to an L-shaped metal section 17 and to an L-shaped metal section 19 (external connections). In each of the four pairs of connection lamellae (13), the two lamellae are separated from one another by a lamella 14 made of electrically insulating material, and form together with this lamella 14 a set

  said micro-band having a relatively low inductance.

  These four micro-bands extend between the L-shaped sections 17 and 19 and the capacitor winding 3. As shown in FIG. 7, it is only in the vicinity of the L-shaped sections 17 and 19 and the capacitor winding 3 that

  the connection lamellae are separated from each other.

  In the unrolled state of the winding, the slats of

  nexion belonging to the same pair are

  close by (adjacent). The slats of

  Both the anode foil and the cathode foil are distributed evenly along the length of the foil in question, that is to say that the points where the connecting lamellae are connected to the corresponding foils lie at intervals

  about equal. L-shaped sections 17 and 19 are electrically

  isolated from each other by a plate 21 of electrically insulating material and together form a

  T-construction which also includes a micro-

  low inductance band. This last micro-band is formed by the opposite wings of the L-shaped sections 17 and 19,

  wings that are electrically isolated from each other.

  With each of the sections in L 17 and 19 of the con-

  the denser shown in FIGS. 1 to 4,

  two threaded connection sockets 23 and 25 (con-

  external connections). The connecting bushes 23 and are located symmetrically with respect to the plate 21 (see FIG. 2), while the connecting bushes 23 are connected to the anode foil and the connecting bushes 25 are connected to the cathode foil . Since the L-shaped sections 17 and 19 are entirely inside the capacitor box 1, the connection bushings 23 and 25 pass through.

cover 5.

  As explained later in this discussion with reference to FIGS. 8 to 10, the capacitor

  not only has equivalent series resistance

  relatively low, but in combination with it,

  it also has an equivalent series inductance rela-

  low, such that the capacitor is suitable for

  especially for high frequency applications.

  According to the second embodiment of a con-

  according to the invention, the embodiment shown in FIGS. 5 to 6, the T-shaped construction formed by the set of L-shaped sections and the plate

  insulation, is provided in a place other than in the

  denser according to Figures I to 4. As the condensate

  in FIGS. 5 to 6 has a close resemblance

  with the capacitor according to FIGS. 1 to 4, it is

  5 to 6, the same references as in FIGS. 1 to 4. The T-construction of the capacitor

  according to FIGS. 5 to 6 is partially in

  and partly outside the casing 1, the wings of L-shaped sections 17 and 19 passing through the covers 5. On each of the lower faces (see Figure 5) of the L-shaped profiles, two bushes of

  connection 23 and 25. This allows you to mount the

  of the T-construction directly against a power strip. For the rest, the

  capacitors according to FIGS. 1 and 5 are of construction

identical.

  As explained hereinafter with reference to FIGS. 10 and 11, the capacitor according to FIGS. 5 to 6 does not only have a relatively low equivalent series resistance but also, in

  combination with it, an equivalent series inductance

  relatively low, such as the capacitor

  especially for high-frequency applications

  accordingly. The specifications of the capacitors according to FIGS. 8 to 11 are as follows FIG.

  capacitor of the type according to FIGS. 1 to 4.

  - capacity 27,000 mF, - operating voltage 20 V, - temperature 25 ° C, - inductance 1,82 nH, - number of pairs of connection lamellae (13, 15) four. Figure 9

  capacitor of the type according to FIGS. 1 to 4.

  - capacity 27,000 mF, - operating voltage 20 V, - operating temperature 250C, - inductance 2,54 nH, - number of pairs of connection lamellae (13, 15)

two.

  FIG. 10 - known capacitor of the type according to FIGS. 1 to 4,

  capacitor which, however, is not equipped with micro-

  strips between the capacitor winding and the

  L-spun, - 9000 mF capacity, - 20 V operating voltage, - 25-C operating temperature, - 25, 32 nH inductance,

  - number of pairs of connection lamellae: two.

  FIG. 11: capacitor of the type according to FIGS. 5 to 6, capacitance 10.000 mF, operating voltage 6 V, operating temperature 250 C, inductance 2.00 nH, number of pairs of connection lamellae , 15) four.

  For equivalent series impedance Z indi-

  graphs in Figures 8 to 11, the relationship between

  The following is valid depending on the frequency Z = ESR + ESC + ESL, where ESR is the equivalent series resistance ESC is the equivalent series capacity, and

  ESL is the equivalent series inductance.

  As -m Figures 8 to 11 also represent

  curve Z than the ESR curve, and that the contribution

  the Z-curve of the equivalent series ESC capacity is negligible for frequencies higher than the

  frequency of resonance (close to the minimum in the

  be Z), it turns out that for each higher frequency

  At the resonance frequency, the difference between the Z curve and the ESR curve can be considered as the contribution of the ESL equivalent series inductance to the equivalent series impedance Z.

  If we compare Figures 8 and 9 in the figure

  10, it can be seen that, for a capacitor according to the invention, at frequencies greater than the frequency

  resonance, the slope of the curve Z and thus the inductive

  ESL equivalent series is significantly less pronounced than

  thanks to the micro-bands provided between the winding

  capacitor and L-shaped profiles. In addition,

  8 and 9 demonstrate that a doubling of the number of

  pairs of connecting lamellae give rise to the increase

  ESR equivalent series resistance. In comparison

  Figure 11, we arrive at a conclusion

  similar to the capacitor according to

  the invention as represented by FIGS. 5 and 6.

  It is clear that micro-ban connections

  low inductance as described above,

  are not limited to electromagnetic wound capacitors

  in addition, they can be advantageously applied in capacitors not

electrolytic dry.

Claims (2)

  1. Capacitor comprising a winding of   capacitor (3) which is in a casing (1) fer-   with a cover (5), and an anode sheet   (9) as well as a cathode sheet (11) are   connected to at least two external terminals (23) and (25) by a number of internal connecting strips (13) and (15) distributed over the length of the sheets,   characterized in that the inter-   nes include electric micro-bands, which are   each formed by two conductive flexible strips   these electricity (13) and (15), separated from each other by an electrically insulating lamella (14),   while one of the two conductive lamellae   a microstrip is connected to the anode foil of the capacitor winding, and the other is connected to the cathode foil of the capacitor winding, and this at a location contiguous to the common point of the conductive strip and the anode sheet.   2. Capacitor according to claim 1, characterized   characterized in that said external terminals (23) and (25) comprise two L-shaped metal sections (17) and (19), separated from each other by an insulating layer (21) and connected to the winding of capacitor by said micro-strips.