JPS59115510A - Oil-immersed metallized film condenser - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an oil-immersed metallized film capacitor, in which an insulation margin is provided at the end of the vapor deposited electrode in the width direction, an insulation groove is provided in the length direction, and a fuse is provided between the insulation groove. When a part of the dielectric of an oil-immersed metallized film capacitor partially breaks down, the short-circuit current that flows causes the vapor deposited film near the contact with the sprayed metal to scatter, releasing that part from the circuit and causing an accident. An object of the present invention is to provide an oil-immersed metallized film capacitor that can stably obtain a self-protection function that prevents the occurrence of oxidation, and has little capacity reduction.

Traditionally, oil-immersed metallized film capacitors are made of plastic film dielectrics such as polypropylene film, polyethylene terephthalate film, polystyrene film, and polycarbonate film.
．． Two vacuum-deposited metallized plastic films with a thickness of 0.02 to 0.03 μm are twisted together and wound to obtain a capacitor element, and metals such as solder and zinc are thermally sprayed on both end surfaces of the capacitor element to form a contact layer. The electricity obtained by
1 Connect the lead wire or terminal to the power section, store it in a case, vacuum dry it, heat it, and immerse it in oil. .

The oil-immersed metallized film capacitor constructed in this manner has a dielectric film that is not easily formed during the current test due to insulation defects in the plastic film and insulation defects formed during metal deposition of the electrodes. il; Partial destruction may occur. However, since the electrode is an ultra-thin layer formed by vacuum evaporation, this part (deposited film DJi l
Since the scattering of ij is 0f, the insulation generally recovers and the capacitor becomes useless. early 11
In -2Fi, the deterioration of the dielectric material is only visible at 51, but the destruction progresses little by little, with some of the destroyed parts as the nucleus. Therefore, there was a danger that smoke and ignition would eventually occur.

For this purpose, various safety devices such as pressure fuses are employed, which can prevent abnormal situations in the capacitor, but on the other hand, this increases the volume of the capacitor and increases costs.

In addition, in order to improve the above-mentioned drawbacks in dry type metallized film capacitors, an insulating groove 4 is provided in the vapor-deposited electrode 2 of the metallized film 1 to extend the electrode 2 in the length direction, as shown in the 11th item 1. Divide it into multiple parts and use it when the capacitor is abnormal.
A method has been proposed that does not involve cutting only this part. Furthermore, as shown in Japanese Unexamined Patent Publication No. 57-154823 p+, there is a method of improving the self-safety function by providing a vapor-deposited film removal section in a portion of the vapor-deposited film that does not face the electric kettle in a ratio of 1=1. be. However, when experiments were conducted applying these conditions to oil-immersed metallized film capacitors, the self-protection function could not be obtained in any case, and the capacitors emitted smoke and caught fire. The reason for this is that when using oil-immersed metallized film capacitors,
Due to the presence of insulating oil in the part where the deposited film is scattered, the -
It is considered that part of the energy when ffll is destroyed is absorbed by this, making it difficult for vapor deposition +B'i to scatter.

Therefore, for oil-immersed metallized film capacitors, it is necessary to consider conditions different from those for dry metal ratio film capacitors.

Hereinafter, the present invention will be explained in detail based on the embodiments shown in FIGS. 2 to 4.

Example 1 Aluminum evaporation 1 resistance 11η3Ω/・thickness 91
Lm metallized polypropylene film 11 with a width of 1.0%
Insulating grooves 14 are provided at intervals of P-25 mm, and a fusing slot (hereinafter referred to as F slot) 15 is formed between these grooves, and the length G between these grooves is 3 rra, and the total length G is 1.
A capacitor element with a capacitance of 5 μF was obtained by winding a capacitor element with a capacitance of 5 μF, and after forming a contact layer on both end faces of the element by metal spraying, the terminals were connected and stored in a container, and after heating and vacuum drying, it was impregnated with insulating oil. It was then sealed and used as a sample. 12
is a vapor deposition electrode, and 13 is an insulation margin.

Note that the width B of the F slot 15 is set to 1. taking into account voltage resistance 46 and capacity loss. It was set to On+m. Further, the metallized film 11 without the F slot 4 was used as a comparison sample. Furthermore, the voltage application test was carried out at an ambient temperature of 80°C and an applied voltage of 48°C.
The application time was 0 VAC and 1000 hours. Further, in the self-safety function test, the ambient temperature was set to 100° C., and the dielectric was forcibly destroyed by applying cumulative overvoltage, and the presence or absence of smoke was checked at this time.

The results are shown in Table 1.

Table 1 Example 2 A metallized polypropylene filter 11 with an aluminum vapor deposition film resistance of 3Ω and a thickness of 91Lm is provided with insulating grooves 14 of 1mm width at intervals of 25mm, and F slots 15 are formed between them.
A capacitor element with a capacitance of 5 μF was obtained by winding metallized films with different lengths G and the total length between them. After forming a contact layer on both end faces of the element by metal spraying, the terminals were connected with leads and placed in a container. After storing and heating and vacuum drying, the insulating groove was impregnated and sealed to obtain Trial 3. The F slot 150 width G and test conditions at this time are (Example 1
) is the same as

The results are shown in Table 2.

Although it is easy to obtain the second surface self-safety function, this insulating groove insulation margin results in capacitance loss of the capacitor. On the other hand, if the interval P is increased, it becomes difficult to obtain a self-safety function. Therefore, the GCF slot 15 is provided in order to increase the insulating groove interval P and to make it easier to obtain a self-safety function. As a result, by providing the F slots 15, the self-security function can be stably obtained, and the total length G between them is preferably 12I or more.

Further, if the deposited film resistance 11 becomes 8 Ω/port or more, the capacitance decreases significantly, so a value of 1 is desirable.

As mentioned above, in the above embodiment, the width G of the F slot 15 was set to 1.0 nn, but the withstand voltage was determined based on the performance and capacity.
(Taking loss into consideration, a tone of 0.3 to 1.0 is appropriate.

Furthermore, as a result of additional examinations of vapor-deposited metal plastic films, it was found that when the vapor-deposited metal is zinc, the reduction in capacitance jtt is smaller than that of aluminum, so that it is possible to tolerate up to 15Ω, where the resistance value of the vapor-deposited film becomes unstable. There was also no difference in self-security function.

In addition, the present invention provides an F thrower 15 between the insulation rA 14, and examines its self-protection function and capacitance change in continuous energization tests depending on the conditions, and uses polypropylene as a dielectric. Although vegetable oil was used as the film and insulation oil, similar results can be obtained with other plastic films such as polyethylene terephthalate film, polycarbonate film, polystyrene film, and other insulation grooves.

Therefore, according to the present invention, since the capacitor is oil-immersed and has a self-protection function, a capacitor with extremely high reliability and safety (and good productivity) can be obtained, and the economical effect is extremely large.

[Brief explanation of drawings]

Figure 1 is a plan view of the main parts of a conventional self-protection type metallized film capacitor in which insulation grooves are provided in the metallized film.
3 and 3 are plan views of main parts of different embodiments of the oil-immersed metallized film capacitor of the present invention, and FIG. 4 is an enlarged plan view of the main parts of the oil-immersed metallized film capacitor of the embodiment of FIG. 3. 1.1: Metallized film 3.13: Insulating margin 4
．． 14: Insulating groove 15: Fusing slot Patent applicant 1 "Capacitor Industrial Forest Company" Figure 1 Figure 3 Figure 3 Figure 2 Procedural amendment (voluntary) Commissioner of the Japan Patent Office Mr. Aio Wakasugi 1 Display of the case 1982 Patent Application No. 229148C J2 Name of the invention: Oil condition Metallized film capacitor 3, Relationship with the case by the person making the amendment Special pestle applicant 4, Subject of the amendment: "Important of the detailed explanation of the invention in the specification" 5. Contents of amendment (1) The second line from the bottom of page 7 of the specification is amended as follows. The width B of 15 and the test conditions are (implemented) (2) The 5th line of page 9 of the Mei M is corrected as follows.

Claims (5)

[Claims] (1) At least one side of the dielectric film is provided with an insulating margin at the end in the width direction, and an insulating groove that divides the vapor-deposited electrode into a plurality of pieces in the length direction. Construct a metallized film in which a using slot is formed, wrap the metallized film in a thin layer (on both sides, with the insulating margin part opposite tit!I), and apply solder to both ends of the metallized film. An oil-immersed metallized film capacitor characterized in that -11 is thermally sprayed with a metal such as lead to form an electrode lead-out portion and impregnated with insulating oil. (2) The oil-immersed metallized film capacitor described in item 1 of the scope of Patent D14, characterized in that an insulating groove is formed leaving a part of the vapor-deposited electrode on the electrode extraction side. (3) Patent claim or claim 2, characterized in that the spacing G between the fusing slots is 3 mm or less, and the total spacing G of the fusing slots existing between the insulating grooves is 12 or less. Oil-immersed metallized film capacitors as described. (4) The oil-immersed metal according to claim 1, 2, or 3, wherein the vapor-deposited metal is made of aluminum and has a film resistance value of 3 to 8 Ω/(]. film capacitor. (5) Claim 1, 2, or 3, characterized in that the vapor-deposited gold II1 is made of zinc, and its film resistance is 3 to 15 Ω/O. Oil-immersed metallized film capacitor.