CN203351426U

CN203351426U - Thin film capacitor

Info

Publication number: CN203351426U
Application number: CN 201320266676
Authority: CN
Inventors: 孔晓宇
Original assignee: Wuxi Institute of Commerce
Current assignee: Wuxi Institute of Commerce
Priority date: 2013-05-15
Filing date: 2013-05-15
Publication date: 2013-12-18
Anticipated expiration: 2023-05-15

Abstract

The utility model discloses a thin film capacitor. The thin film capacitor comprises a shell, leading-out terminals, an insulating positioning cover, connecting copper strips and capacitor chip units; the three uniformly distributed leading-out terminals are fixed to the shell in an insulating manner through the insulating positioning cover, and lower ends of the leading-out terminals are connected with the three capacitor chip units arranged in the shell through the connecting copper strips to form a triangular connecting structure; the capacitor chip units are formed by winding a thin film, a metal coating is arranged on the thin film, and the thickness of the metal coating is 35% to 45% of the total thickness of the thin film. The structure can enable current of the leading-out terminals to be uniformly distributed, the influence of high-frequency current of equipment on the chip is effectively shielded, an thickening area of the thin film coating is designed to be greatly widened, so that product performance of absorbing harmonic waves is better, thereby greatly reducing heat generation, delta connection is formed inside the capacitor, three electrodes are led out in a manner of delta connection, complicated wiring of a plurality of capacitors are is needed, and the size of the capacitor is greatly reduced at the same time.

Description

A kind of film capacitor

Technical field

The utility model relates to a kind of film capacitor.

Background technology

In the application scenario of power electronic equipment, for administering harmonic wave and improving power factor and all can use ac filter electric capacity exchanging to hold.Especially in some powerful current transformer/inverter occasions, the operating frequency of equipment itself is very high, very large to the harmonic current of electrical network feedback, if do not have ac filter electric capacity that impedance path is provided, will have a strong impact on electrical network and relevant device normal operation.Because the occasion of application is important, and in capacitor when work, is large by electric current, and heating is serious, and easily heating is serious and reduce the life-span and even lost efficacy to make this electric capacity, therefore very high to the requirement of this electric capacity.

In this occasion, capacitor commonly used generally has two kinds: a kind of for single-phase, by the external three-phase line of client, and many radiating surfaces that increase in parallel, solve the super-high-current problem, and but so loosely organized, the shared volumetric spaces of electric capacity is large, cost is high; Another kind is as three-phase integrated, inner three electric capacity delta connections, the heat radiation of oil formula structural reinforcing, but overcurrent capability low (maximum can only reach 40 ~ 50A), anti-harmonic wave ability is little, often be not suitable for the application scenario of the large electric current of this higher harmonics, and have the danger of leakage of oil, to reaching environmental protection and safe and reliable totally unfavorable.

The utility model content

The utility model purpose is that the defect existed for prior art provides a kind of more convenient, more safe and reliable, and life-span that can effective guarantee equipment and stable capacitor.

The utility model for achieving the above object, adopts following technical scheme: a kind of film capacitor comprises housing, exit, insulation locating cover, connects copper strips and capacitor core unit; Three equally distributed described exits are fixed by insulation locating cover and casing insulation, and the exit lower end connects and composes the triangle syndeton by described connection copper strips and three described capacitor core unit that are located in described housing; Described capacitor core unit is that winding film forms, and described film is provided with the coat of metal, and described metal layer thickness is overall film thickness 35% to 45%.

Preferably, described insulation locating cover is the locating cover that plastics are made.

Preferably, stating housing is that non-magnetic metal is made.

Preferably, described housing is the cylinder that metallic aluminium is made.

Preferably, described exit is copper nut or brass bolt, and it is chimeric fixing by the fairlead on described insulation locating cover.

Preferably, described connection copper strips is zinc-plated braiding copper strips.

Preferably, be filled with the potting compound for the capacitor heat radiation in described housing.

Preferably, described potting compound is high heat conductive flame-retarding polyurethane.

The beneficial effects of the utility model: (1) this structure can make the exit CURRENT DISTRIBUTION even, the effectively impact of shielding device high-frequency current on fuse, design thin film coating thickened area is widened greatly, make product absorb harmonic performance better, thereby greatly reduce heating, and the convenient inner delta connection that forms, totally three electrode corner connections are drawn, facilitate the client to install, without many complicated wiring of electric capacity, greatly reduce the electric capacity volume simultaneously.

(2) capacitor of the present utility model, changed traditional thin-film capacitor mentality of designing, flow to principle according to high-frequency current, design thin film coating thickened area is widened greatly, effectively reduces the ESR value, makes product absorb harmonic performance better, install more convenient, more safe and reliable, and the life-span of energy effective guarantee equipment and stable, heating is still less.

(3) capacitor of the present utility model, make product have the super-high-current ability and the little advantage of volume is integrated in one, and installs more conveniently, and can effectively reduce cost, and volume has also reduced simultaneously, and the structure of one also is convenient to install and use more.

(4) the utility model, owing to having reduced caloric value and having strengthened heat sinking function, does not need to adopt the heat radiation of oil-immersed type structural reinforcing, and leakage and flammable problem can not occur, and the dry construction product is safer, and is not subject to impact and the restriction of installation environment.

The accompanying drawing explanation

Fig. 1 overall structure schematic diagram of the present utility model;

Fig. 2 internal structure schematic diagram of the present utility model;

Fig. 3 cartridge units triangle of the present utility model catenation principle figure;

The embedded structure schematic diagram of Fig. 4 terminal of the present utility model and locating cover;

The membrane structure schematic diagram of Fig. 5 cartridge units of the present utility model inside.

Embodiment

Shown in Fig. 1, Fig. 2, be a kind of film capacitor, comprise housing 2, exit 4, insulation locating cover 3, connect copper strips 6 and capacitor core unit 1; Three equally distributed described exits 4 are fixing with shell 2 insulation by insulation locating cover 3, and exit 4 lower ends connect and compose the triangle syndeton by described connection copper strips 6 and three described capacitor core unit 1 that are located in described housing 2.Described exit 4 is copper nut or brass bolt, and it is chimeric fixing by the fairlead on described insulation locating cover 3.The insulation locating cover 3 that plastics are made is taken into account the function of insulation electric capacity core body and shell simultaneously; Totally three of exits 4, inner capacitor core unit 1 also has three, just can connect three capacitor core unit 1 triangles draw neatly by the tin welding connecting line like this.Fig. 3 is cartridge units triangle catenation principle figure.

Flow to the coating wide cut thickening of characteristics design capacitance fuse edge according to high-frequency current, reduce the ESR value of electric capacity, can guarantee that electric current flows to evenly when fuse electric capacity is worked, thereby greatly reduce the mandrel body heating.Described housing 2 is made for non-magnetic metal; General housing 2 can be the cylinder that metallic aluminium is made, and prevents that shell 2 from producing eddy current and generating heat at the alternating electric field of high frequency.

The embedded structure schematic diagram that Fig. 4 is exit 4 and insulation locating cover 3; Connecting copper strips 6 is zinc-plated braiding copper strips, and its each several part flexibly connects, and can in assembling process, not draw pine to pad.The thickness of braiding copper strips is depending on concrete overcurrent situations, in the situation that high-frequency current, due to skin effect, the annealed copper wire of multiply is little more a lot of than the heating of copper strips or copper coin.

In Fig. 5, reel and form for film 8 in capacitor core unit 1, and film 8 is provided with the coat of metal 7.The described coat of metal 7 thickness are overall film thickness 35% to 45%.Best, the coat of metal 7 thickness are overall film thickness 40%.Can reduce like this ESR value of electric capacity, can guarantee that electric current flows to evenly when fuse electric capacity is worked, thereby greatly reduce the mandrel body heating.Be filled with the potting compound 5 for the capacitor heat radiation in described housing 2.Described potting compound 5 is high heat conductive flame-retarding polyurethane, can effectively guarantee the electric capacity heat radiation.It has very high conductive coefficient, is 2.5 ~ 3 times of ordinary epoxy resin, guarantees the good heat radiating of product.Simultaneously, because be solid-state dry type, there do not is the danger of oily formula electric capacity leakage of oil, do not have the restriction of installation site and angle yet.

The foregoing is only preferred embodiment of the present utility model, not in order to limit the utility model, all within spirit of the present utility model and principle, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection range of the present utility model.

Claims

1. a film capacitor, is characterized in that, comprises housing, exit, insulation locating cover, connects copper strips and capacitor core unit; Three equally distributed described exits are fixed by insulation locating cover and casing insulation, and the exit lower end connects and composes the triangle syndeton by described connection copper strips and three described capacitor core unit that are located in described housing; Described capacitor core unit is that winding film forms, and described film is provided with the coat of metal, and described metal layer thickness is overall film thickness 35% to 45%.

2. a kind of film capacitor as claimed in claim 1, is characterized in that, described insulation locating cover is the locating cover that plastics are made.

3. a kind of film capacitor as claimed in claim 1, is characterized in that, described housing is that non-magnetic metal is made.

4. a kind of film capacitor as claimed in claim 2, is characterized in that, described housing is the cylinder that metallic aluminium is made.

5. a kind of film capacitor as claimed in claim 1, is characterized in that, described exit is copper nut or brass bolt, and it is chimeric fixing by the fairlead on described insulation locating cover.

6. a kind of film capacitor as claimed in claim 1, is characterized in that, described connection copper strips is zinc-plated braiding copper strips.

7. a kind of film capacitor as described as claim 1 to 6 any one, is characterized in that, is filled with the potting compound for the capacitor heat radiation in described housing.

8. a kind of film capacitor as claimed in claim 7, is characterized in that, described potting compound is high heat conductive flame-retarding polyurethane.