JPS59194303A - Oil-filled 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] Industrial applications The present invention is applicable to electrical equipment including electric power.

This relates to an oil-immersed condenser "If" used for communications, etc.

Conventional structure and problems Conventional oil-filled capacitors use ester oils such as DOP (dioctyl phthalate), TIP (inflobylphenyl phosphate), AB (alkylbenzene), and DAA (diallyl) as insulating oil. alkanes), AD
Hydrocarbon insulating oils such as P (alkyldiphenyl) + AN (alkylnaphthalene) and MO (mineral oil) have been used singly or in combination. In reality, additives such as epoxy stabilizers, phenol stabilizers, phosphite stabilizers, metal soap stabilizers, and organic tin compounds were added to the insulating oil either singly or in combination (especially Publication number 62-24239.

JP-A-53-35999, JP-A-53-3600
Publication No. 0, JP-A-54-15158, JP-A-54
(See Japanese Patent Application Laid-open No. 16658-16658 and Japanese Unexamined Patent Publication No. 16659-1982).

This is because when oil-filled electrical equipment is used for a long period of time, the insulating oil deteriorates due to thermal and electrical energy and decomposition products increase, which in turn causes a chain decomposition reaction that advances the decomposition reaction and deteriorates the initial electrical characteristics over a long period of time. In order to stop such a chain decomposition reaction, a stabilizer is added to prevent the chain decomposition reaction from occurring. 1. For the same purpose, JP-A-47-26698 and JP-A-47-27
No. 397 and JP-A No. 47-27398 disclose that a special Nran compound is added as a stabilizer to halogenated synthetic insulating oil. In this case, the additive also releases minute electrical discharge energy and thermal energy during long-term use. Because it functions to capture hydrogen chloride that is decomposed and produced from halogenated synthetic insulating oil, it is able to maintain its initial electrical characteristics over a long period of time. However, even though halogenated synthetic insulating oil has a cylindrical dielectric constant, high heat exchange properties, and flame retardancy, it is a sentient substance and is currently not produced in Japan and its use is prohibited. In any case,
In this way, stabilizers are added to conventional insulating oils as additives to chemically react with residual impurities and decomposition products in the insulating oil to stop chain decomposition reactions, thereby maintaining the initial electrical properties over a long period of time. It is.

On the other hand, one of the performance requirements for oil-filled capacitors is whether they are nonflammable or flame retardant. One of the factors that determines this non-combustibility or flame retardancy is the gas that is filled into oil-filled capacitors.

There is a question of whether the oil is non-flammable or flame-retardant, but Japanese Patent Publication No. 57-3208 discloses an insulating material that makes the capacitor element completely non-flammable or flame-retardant and is not toxic to the human body. The oil is proposed by mixing 10 to 60 parts (volume ratio) of DAA into orthophosphoric acid ester containing 3 to 4 aromatic rings. proposed an electrical insulating oil that not only increases flame retardancy but also eliminates corona discharge and suppresses melting of plastic by completely mixing phosphate ester with hydrocarbon insulating oil. −.242
Publication No. 39 proposes an electrical insulating oil in which an epoxy compound is added for the purpose of removing damage caused by hydrogen chloride to an insulating oil that is a complete mixture of a hydrocarbon compound and a phosphor-1 or phosphite organic phosphorus compound. There is. The initial dielectric properties of these conventional oil-immersed capacitors completely impregnated with insulating oil were changed to an oil-immersed capacitor A consisting of two sheets of electrode paper with zinc (Zn) deposited on both sides of the paper and two sheets of polypropylene dielectric film. Measurements were made using an oil-immersed capacitor B consisting of two sheets of electrode paper with aluminum (Al) completely vapor-deposited on both sides of the paper and two sheets of polypropylene dielectric film. Figure 1 shows the initial dielectric loss factor (ta) of these conventional oil-immersed capacitors at 100°C.
nδ). The measured voltage is an AC voltage of 601-)t, and the horizontal axis of FIG. 1 represents the potential gradient divided by the applied voltage constant film thickness. In this case, the insulating oil is DOP and an epoxy stabilizer (epoxidized soybean oil)? I wt
(Characteristics) Epoxidized soybean oil (11 wt%) is added to a mixed oil of combustible insulating oil (characteristics) and tris(isopropylphenyl) boschite and diallylethane (DAE) r, y in a ratio of 2:3 (volume ratio). This is flame-retardant insulating oil (characteristic ■) added and mixed.In the figure, the solid line is the characteristic for oil-filled capacitor A (characteristic A), and the dotted line is the characteristic for oil-filled capacitor B (characteristic B). According to the above, the higher the potential gradient, the higher the tan δ, and the oil-filled capacitor A was the worst.The oil-filled capacitor B had a lower tan δ than the oil-filled capacitor A, but The graph shows a remarkable increasing trend in the υ high potential gradient region.As can be seen from the figure, the tan δ of the flame-retardant phosphate ester and DAE mixture oil is extremely large, while it has the characteristics of flame-retardant metal. , the dielectric properties are worse than that of flammable DOP.The smaller the volume ratio of DAE to phosphoric acid ester, the higher the flame retardancy, but the dielectric properties are worse.On the other hand, phosphoric acid DA for ester
Volume ratio of E is 60vol1% Phosphate ester to DAE
= 2 to 3), the dielectric properties are improved but the flame retardancy is lost, and it is only when the dielectric properties are increased by about 1% that 90 TO becomes D.
It exhibits dielectric properties similar to those of OP, and there is no significant difference in characteristics from DOP. Therefore, when these conventional oil-immersed capacitors impregnated with combustible insulating oil are used under a metal potential gradient, the heat generated by the increase in tan δ is large and causes thermal breakdown, so that the use is limited to areas where the potential gradient is low. However, oil-immersed capacitors impregnated with phosphate ester or a mixture of phosphate ester and other insulating oil exhibit nonflammability or flame retardance, eliminate corona discharge, and suppress plastic melting. However, there remains the issue of bringing out all the characteristics to prevent tan δ from increasing at higher potential gradients.

Purpose of the Invention The present invention is an oil-immersed capacitor that is non-flammable or flame-retardant. All lubricants have the characteristic that tan δ does not increase even with a higher potential gradient than was previously possible.
The purpose is to provide a new oil-filled capacitor that is easy to clean.

Structure of the Invention To accomplish this, the present invention impregnates a capacitor element consisting of an insulating oil consisting of a main insulating oil and an additive added thereto, and a dielectric interposed between the electrode pairs. The main insulating oil is a phosphate ester alone or a mixture of a phosphate ester and an organic oil/compound, and the additive is at least one type of silane coupling agent! be.

Description of Examples Phosphate esters used in the present invention include, for example, tricresyl phosphorus (TCP).

cresyl diphenyl phosphate (GDP), ) liphenyl phosphate (TPP), ) lis(impropylphenyl) phosphor) (TIP) + phenyl bis (isopropylphenyl) phosphate (PBIP), diphenyl isobropylphenyl phosphate 1- (DPIP), trioctyl phosphate (TOP), )')
Kinv=ru*suphosphate (TXP) + octyl diphenyl phosphate (ODP), etc. can be used alone or in combination. On the other hand, examples of organic oily compounds used in combination with phosphoric acid esters include DAA, 1-lylylalkane (
TAA), oligoallyl alkanes such as dibenzyltoluene (DBT), hydrocarbon insulating oils such as AB, AN, alkyldiphenyl (ADP), MO, polybutene (PB), phthalate esters, and fats. a
(Dibase i)ester, fumaric acid ester.

Maleic acid ester, epokinated ester, 1-melinate ester, benyl neoalkyl carbonate (B
Ester oils such as NC) and quinlyltolylsulfone (X
TS), alkyl diphunyl ether (ADH), etc., all of which are used alone or in combination. There is no problem in adding various conventional stabilizers to these organic oily compounds.

The additive has the following general formula % (in the above formula, R1 is hydrogen or 01-C4 alkyl, R2 is 01-CB alkylene or 06-C'+8
is a substituted or unsubstituted arylene, and R3 is 01-
C8 alkyl+Cj~C8 alkoxy/,06~G+11
Substituted or unsubstituted aryl + CN to C8 anloxy or C6 to 018 substituted or unsubstituted aryloxy, R4 and R5 are C1 to CB alkokyne 7C1
~C8 anloxy or C6~C1B substituted or unsubstituted lyloxy) or the following general formula [(wherein R1 is C1~C8 alkylene or UC6~
C18 substituted i, shi< are unsubstituted arylene, R2 ha C1-C8 alkyl, C1-C8 alkoxy + C6-C
'+8 Substituted or unsubstituted aryl
Alcogine, C1-C8 anloxy or 06-C1
selected from st-substituted or unsubstituted aryluogyne)
or a silane coupling agent having the following general formula (in the above formula, R1 is hydrogen or C1-C4 aminoalkyl, R2U c', ~C8 alkylene"&kl
dGb~ate substituted or unsubstituted alinolene, R3 ha C1~C8 alkyl, 01~CB alkoxy+
G6~C+a substitution or (unsubstituted aryl, 01~C
8 acyloquine' or 06-C18 substituted or unsubstituted ly-ruoxy, and R4 and R5 are C1-C8
Alkoxy, 01-C8 anloxy or FiGb-C
18 substituted or unsubstituted aryloxy) or 06
~('+8 substituted or unsubstituted arylene, R2
Ha01~C8 alkyl, 01~C8 alkoxy, C6~
C'j8 substituted or unsubstituted aryl+Cj-C8 acyloxy or 06-G+8 substituted or unsubstituted aryloxy')s Rs and R4 are C1-C8 alkoxy, 01-C8 anloxy or 06-C1a substituted or unsubstituted aryloxy ) or i/I'i'.

The following general formula % formula % (in the above formula s R11f c1-C8 alkylene t7j
il: 06-C'18 substituted or unsubstituted arylene, R2BG+-C8 alkyl + C+-C8 alkokyne, 06-C18 substituted or unsubstituted aryl, 01-
C8 anruoxy or C6-a1s substituted or unsubstituted ri-luoquine, R3 and R4 are C1-C8
Alkoxy, 01-c8 anloxy or 06-Cr
(selected from a-substituted or unsubstituted ruoxy)
A silane coupling agent having the following general formula:
Alkylene or UC+~C8C1~C8 alkoxy2 is hydrogen, 01~C8 alkyl, 01~C8 alkoxy.

06-C18 substituted or unsubstituted aryl, 01-C8
acyloxy or C6-C18 substituted or unsubstituted aryloxy, R4 and R6 (ri hydrogen, C1
~C8 alkoxy, 01~C8 anruoxy'! i'c
(selected from lt'icb to C18 substituted or unsubstituted aryloxy)'ff: A silane coupling agent having the following is used alone or in combination.

Preferred silane coupling agents in J) are as follows.

(a) γ-methacryloquinepropyltrimethoxine OH.

CH22G-C-0-C3H6Si(OCH3)51 (b) γ-chrysitoquine propyltrimethoxine run CH2-CHCH20C3H6Si(OCH3)3\
/ (c) N-β(aminoethyl)γ-aminopropyltrimethquine silane H2NC2H4NHC5H6Si(OCH3)5)
N-β(aminoethyl)γ-aminopropylmethyldimethquine silane H2NC2H4NHC3H6Si(OCH3) 2CH
3 G+1 γ-Aminoprobyltrietquinran H2
NC3H6Si (OC2H5) 5 (to) γ-mercaptopropyltrimethquine silane H8C3H6S engineering (Q
C; H5) 3 (g) γ-talolopropyltrimethoxysilane CI
C3I(6Si(OCH3)5 Vu Vinyltris(β-methyneethoxy)silane CH2=CH3i(OC2H40CH3)x And the silane coupling agent has two or more functional groups in the molecule, usually are silicon compounds with different reactivity. The silane coupling agent is usually represented by the general formula YR-8i -X2 t 3 , where x1 to X3 (hydrolyzable Typical examples include an alkoxy group, an acyloxy group (especially an acetoxy group), and a chlorogen group (especially a chloro group).

Further, Y represents various organic functional groups, such as vinyl group,
Representative examples include organic functional groups containing temino groups, imino groups, chloro groups, epoxy groups, mercapto groups, peroxy groups, ureido groups, etc., which are directly bonded to the S1 atom via the organic group Rfar. ing.

The oil-immersed capacitor of the present invention is made by impregnating an insulating oil containing an effective amount of at least one type of mineral purifying agent into an oil made of a phosphoric ester alone or a mixture of a phosphoric ester and an organic oil compound. However, the effective amount is 0.02 wt% or more, preferably 0.1 wt% or more, based on the phosphoric acid ester tub alone or in a mixture. 3wt%1
In this case, the initial dielectric properties of an oil-immersed capacitor at high temperatures become better as the amount added increases, but when the amount exceeds Swt%, the initial dielectric properties do not improve even if the amount added is increased. However, it showed much better initial properties compared to the additive-free one, and 10
Gold exhibits excellent electrical and dielectric properties even when added in an amount of about wt%. Furthermore, when the addition amount is increased to 20 to 30 wt%, the initial characteristics are temporarily deteriorated, but the initial characteristics are dramatically improved by voltage aging treatment. However, current silane coupling agents are extremely expensive, resulting in extremely costly oil-immersed capacitors;
The preferred addition amount range is i0.1 wt% to 10 wt%.

For electrodes constituting capacitor gold, the dielectric material is Zn or A1.
It is used as an electrode made by full vapor deposition and directly metallized, or as an A1 foil full electrode. -1 A1 If the end of the foil is folded back and a round edge electrode is used to completely relieve the electric field concentration at the electrode end, corona discharge can be suppressed effectively.

Synthetic resin film or paper is used as the dielectric material constituting the capacitor. In particular, when using a roughened synthetic resin film (for example, a roughened polypropylene film) that improves impregnability, the dielectric loss of the film itself is small and the impregnability is good. It is possible to provide an oil-immersed capacitor with

Hereinafter, specific examples of the present invention will be described.

Figure 2 shows the initial jan δ at 100°C of the oil-immersed capacitor according to the present invention, and the capacitor element configuration is the same as in Figure 1, but only when Zn vapor-deposited electrode paper is used, which increases tan δ. It shows. In this case, the insulating oil is a mixture of TIP and DOP% at a ratio of 2:3 (volume ratio), and 11 wt% evaxidized soybean oil.
and γ-methacryloxypropyltrimethoxine run 1
5 wt% was added. Flame-retardant insulating oil (special order ■), TIP, and DAE gold mixed at a ratio of 2:3 (volume ratio) to a mixed oil containing 11 wt% of epoxidized soybean oil and γ-methacryloxypropyltrimethoxy/Nran fs wt%. Added flame retardant insulating oil (characteristic ■) and epoxidized soybean oil '11w to TIP
This is a non-flammable insulating oil (characteristic ①) to which 7 wt% of γ-methacryloquinepropyltrimethquine silane f7 is added. For comparison, epoxidized soybean oil 11 was mixed with conventional TIP and DAE'i in a ratio of 2:3 (volume ratio).
The flame-retardant insulating oil (characteristic ■) with weight addition is also indicated by a dotted line. Note that the detection sensitivity of tan δ has a limit of 0.01%, and values lower than this are not measured and are set at 0.01%.

From FIG. 2, it is clear that the flame-retardant oil-filled capacitors of the present invention exhibit low tan δ characteristics that are far superior to conventional flame-retardant oil-filled capacitors. It can be used at a sufficiently higher potential gradient. In the case of phosphoric acid ester 10o.

Conventionally, tan δ exceeded 1 factor, making it difficult to put it into practical use, but the present invention provides a nonflammable oil-immersed capacitor with electrical properties comparable to conventional DOP. 1 ftc
If the volume ratio of phosphoric acid ester to insulating oil is 10φ or more, corona discharge once generated in oil-immersed capacitors may disappear, or the amount of polypropylene film dissolved in oil may be suppressed. It is possible to provide an oil-immersed capacitor that has the characteristics of a conventional capacitor impregnated with a phosphate ester mixed oil, such as a large amount of water, and has a tan δ characteristic that is much lower than that of the conventional capacitor.

Although the main object of study here was an oil-immersed capacitor with electrodes made of zinc, which has particularly poor tanδ characteristics, similar effects can be obtained for oil-immersed capacitors with electrodes made of aluminum. have

Effects of the Invention As described above, the present invention is non-flammable or flame-retardant, eliminates corona discharge, and suppresses melting of plastic films, and at the same time has an unprecedentedly low tan δ property. Because of this, it can be used with excellent effects even under high potential gradients where conventional capacitors could not be used.

[Brief explanation of the drawing]

FIG. 1 is an initial tan δ-potential gradient characteristic diagram of a conventional oil-immersed capacitor, and FIG. 2 is an initial tan δ-potential gradient characteristic diagram of an oil-filled capacitor according to an embodiment of the present invention. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Zutaka L Itate 4 Cliff (v/P) Figure 2

Claims (6)

[Claims] (1) An oil-immersed capacitor impregnated with insulating oil made by adding at least one type of silane coupling agent to a phosphoric ester alone or a mixed oil of a phosphoric ester and an organic oil compound. (2) One of the 7 ranker spring agents is R1'
R3 1 CH2=C-C-0-R2-3i-R411 R5 (In the above formula, R1 is hydrogen or C1-C4 alkyl, di, B2 is C1-C8 alkylene, or ha C6-01B substituted or unsubstituted is arylene, and R5 is C1 to C8
Alkyl, 01-C8 alkokyne, 06-018 substituted or unsubstituted aryl, 01-C8 anluoki7''!,
Take06-CI8 is substituted or unsubstituted aryl ogyl/, and R4 and R5 are C1-C8 alkogyl/, 01-
The oil-immersed capacitor according to claim 1, wherein the capacitor is selected from C8 anluoquine and 1d06 to C18 substituted or unsubstituted ruoxy. (3) One of the silane coupling agents is 2 (in the above formula, R1 is 01-C8 alkylene or C6-
018 is substituted or unsubstituted arylene, and R2 is C
1-C8 alkyl, 01-C8 alkokene. 06-G+8 substituted or unsubstituted aryl, 01-C8
Anluoquin-1, or C6-CI8 substituted or unsubstituted aryloquine! l, R3 and R4 are C1 to C
8 alcoquine, 01-C8 acyluoquine or C6-C
1B (selected from substituted or unsubstituted aryloquine). (4) One of the silane coupling agents is (in the above formula, R
1 is hydrogen or 01-C4 aminoalkyl)%
R2 is 01~CB alkylene size or 06~018 substituted or unsubstituted arylene, R31l-jl, C
1~C8 alkyl, 01~C8 alkokyne, 06~('
18 substituted or unsubstituted aryl, 01-C8 anloxy"l( is C6-C'1B substituted or unsubstituted aryloxy, R4 and R5 are C1-C8 alkoxy, 01-C8 anloxy or 06-Cj8 substituted or unsubstituted % selected from substituted aryloxy). (5) One of the cincanobbling agents is 2 □ H8-R1-Si -R5 □ 4 (in the above formula, R1 is 01-C8 alkylene or 06-
CI8 is substituted or unsubstituted arylene, and R2 is C
1-C8 alkyl, C1-C8 alkokene, C6-01
8-substituted or unsubstituted aryl, 01-C8 acyloquine, or 06-C18 substituted or unsubstituted aryloxy, R3 and R4 are C1-CE17/l/Kogishi, C1-C8 acyloxy spanning 06-018 substituted or The oil-immersed capacitor according to claim 1, wherein the capacitor is selected from unsubstituted aryloxy. (6) One of the Nran coupling agents is 2 □ C1-R1-3i -R3 (In the above formula, R1 is C1-C8 alkylene or 06-
C18 substituted or unsubstituted arylene, R2 is 0
1-C8 alkyl, 01-C8 alkoxy, 06-G+
8 substituted or unsubstituted aryl, 01-C8 acyloxy-1: 06-C'+8 substituted or unsubstituted aryloxy, R3 and R4UC1-G, flukoxy, C1-C8 acyloxy or C6-C18 substituted or unsubstituted The oil-immersed capacitor according to claim 1, wherein the capacitor is selected from the group consisting of aryl oxene. c'7) One of the Nrankanopring agents is CH2CH-Si-R5-R4-5Ru6 (in the above formula, R1, R3 and R5 are C1-C8 alkylene sweet ha01-C8 alkoxy, R2 is hydrogen, C1-C8 alkyl, 01-C8 alkoxy, 06
~018 substituted or unsubstituted aryl, 01~C8 acyloquine spanning 06~ ('+8 substituted or unsubstituted aryloxy, R4 and R61d hydrogen, 01~
C8 alkokene, 01-C8 acyloxy or 06-
-C8 substituted or unsubstituted aryloxy), according to claim 1.