CN113764180B

CN113764180B - Fireproof power capacitor

Info

Publication number: CN113764180B
Application number: CN202111062104.1A
Authority: CN
Inventors: 曹金; 吴军; 郑伟; 谭千里
Original assignee: Chengdu Wu03 Technology Group Co ltd
Current assignee: Chengdu Wu03 Technology Group Co ltd
Priority date: 2021-09-10
Filing date: 2021-09-10
Publication date: 2022-11-25
Anticipated expiration: 2041-09-10
Also published as: CN113764180A

Abstract

The invention relates to the technical field of power elements and discloses a fireproof power capacitor. The invention provides a novel fireproof design scheme of a capacitor based on shape memory alloy and fire extinguishing gas, namely, on one hand, when the temperature is raised from normal temperature to a preset temperature for judging the occurrence of fire, the characteristics of the shape memory alloy and deformation along with the temperature are utilized, the gas storage chamber is unsealed through the sealed ring body, so that the fire extinguishing gas can be actively released, the purposes of fire prevention and timely fire extinguishing are realized, the fire extinguishing effect is greatly improved, on the other hand, the heat dissipation of the capacitor can be directly carried out, the working temperature of a device can be improved, and the service life of the device is prolonged; and high-pressure fire extinguishing gas in the upper and lower gas storage chambers can be used for inhibiting insulating oil in the shell from seeping out and extruding an oil seepage gap, so that external high-pressure fire extinguishing gas is difficult to enter the shell, further the high-pressure capacitor can be prevented from being damaged, and the service life of the device is further prolonged.

Description

Fireproof power capacitor

Technical Field

The invention belongs to the technical field of power elements, and particularly relates to a fireproof power capacitor.

Background

The power capacitor is widely used in the fields of power transmission, power distribution, power utilization and the like in the occasions of reactive power compensation, filtering, energy storage and the like. At present, a high-voltage power capacitor is generally formed by taking an aluminum foil as an electrode, winding and flattening a polypropylene film as an insulating medium to form a capacitor element, connecting the capacitor element in series and parallel, then placing the capacitor element into a metal container, and finally drying and impregnating insulating oil in vacuum. The power capacitor has the outstanding characteristics of mature technology, high insulating strength, long service life and good reliability. However, since the capacitor is filled with flammable insulating oil, if the insulating oil leaks out for some reason, a fire accident is easily caused (in the operation and use of the power capacitor, the fire accident occurs many times). Thus, the problem of fire protection of power capacitors has been a challenge.

In order to solve the fire-proof problem of the power capacitor, the prior art adopts a double-layer sealed shell structure, so that the fire-proof purpose is realized by using non-combustible liquid (such as water or silicon oil) positioned between an inner shell and an outer shell. The technical scheme also has the following technical problems that (1) non-combustible liquid can be leaked for covering and extinguishing fire after the outer shell is damaged due to overlarge fire, so that the problem of untimely fire extinguishing exists, and the fire extinguishing effect is extremely poor due to the limited quantity of the non-combustible liquid; (2) The non-combustible liquid always surrounds the inner shell, and the heat conductivity coefficient of the non-combustible liquid is far smaller than that of the metal material of the inner shell, so that the problem of being not beneficial to heat dissipation of the capacitor can be caused; (3) The innermost insulating oil may still seep between the inner and outer cases, and a nonflammable liquid may enter the inner case, thereby causing damage to the high-voltage capacitor.

Disclosure of Invention

In order to solve the problems of untimely fire extinguishing, poor fire extinguishing effect, inconvenience for heat dissipation of a capacitor and leakage of insulating oil in the existing fire-proof scheme of the power capacitor, the invention aims to provide a novel fire-proof power capacitor, which can actively release fire extinguishing gas, realize the purposes of fire prevention and timely fire extinguishing, greatly improve the fire extinguishing effect, directly dissipate heat of the capacitor, further improve the working temperature of a device, prolong the service life of the device, inhibit leakage of the insulating oil in the shell by utilizing high-pressure fire extinguishing gas in an upper air storage chamber and a lower air storage chamber, extrude oil leakage gaps, make external high-pressure fire extinguishing gas difficult to enter the shell, further avoid damaging the high-pressure capacitor and further prolong the service life of the device.

The invention provides a fireproof power capacitor, which comprises a capacitor element, a capacitor shell, a capacitor electrode and an insulating sleeve, wherein the capacitor element is arranged in the capacitor shell as a capacitor core, insulating oil is filled in the capacitor shell, the capacitor electrode is led out from the inside of the capacitor shell through the insulating sleeve, and the fireproof power capacitor further comprises a first semi-surrounding body, a second semi-surrounding body, a first sealing ring body and a second sealing ring body;

the first semi-surrounding body comprises a bottom plate and a first annular wall body which are of an integrated structure, the first semi-surrounding body surrounds the bottom of the capacitor shell to form a first air storage chamber surrounded by the bottom plate, the first annular wall body and the shell bottom plate of the capacitor shell, and the first sealing ring body is sleeved on the periphery of the bottom of the capacitor shell and wrapped by the first annular wall body and used for sealing the first air storage chamber at normal temperature, is made of shape memory alloy and can be unsealed through deformation when the temperature is raised to a preset temperature;

the second semi-surrounding body comprises a top plate and a second annular wall body which are of an integrated structure, the second semi-surrounding body surrounds the top of the capacitor shell to form a second air storage chamber surrounded by the top plate, the second annular wall body and the shell top plate of the capacitor shell, the second sealing ring body is sleeved on the periphery of the top of the capacitor shell and is wrapped by the second annular wall body and used for sealing the second air storage chamber at normal temperature, the second sealing ring body is also made of the shape memory alloy, and the second air storage chamber can be unsealed through deformation when the temperature is raised to the preset temperature;

and fire extinguishing gas with the normal-temperature air pressure value higher than the standard atmospheric pressure is respectively stored in the first air storage chamber and the second air storage chamber.

Based on the content of the invention, a novel fireproof design scheme of the capacitor based on the shape memory alloy and the gas for fire extinguishing can be provided, namely, on one hand, when the temperature is increased from the normal temperature to the preset temperature for judging the occurrence of fire, the characteristics of the shape memory alloy, which are deformed along with the temperature, are utilized, the upper and lower gas storage chambers are unsealed through the upper and lower sealing ring bodies, the gas for fire extinguishing can be actively released, the purposes of fire prevention and timely fire extinguishing are realized, the fire extinguishing effect can be greatly improved because the gas storage capacity is far greater than the liquid storage capacity, on the other hand, because the outer peripheral surface of the middle part of the capacitor shell is exposed and uncovered, the heat dissipation of the capacitor can be directly carried out, the working temperature of a device can be improved, and the service life of the device is prolonged. Consider simultaneously capacitor case generally is formed by seamless barrel, casing bottom plate and casing roof concatenation for the place that insulating oil oozes appears most is promptly capacitor case's bottom and top, consequently can also utilize the high-pressure fire-extinguishing gas in the upper and lower two gas storages to restrain the insulating oil in the shell and ooze, and extrude the oil seepage gap, make outside high-pressure fire-extinguishing gas also difficult to enter in the shell, and then still can avoid causing the destruction to high-voltage capacitor, further extension device life. In addition, because the gas leakage mouth that two upper and lower air reservoirs formed because of alloy deformation is relative from top to bottom, consequently can slow down the air current diffusion velocity through the air current hedging effect when two upper and lower air reservoirs leak gas simultaneously, and then the extension is put out a fire with the dwell time around the condenser, further promotes fire prevention fire extinguishing effect.

In one possible design, a heat sink is further included, wherein the heat sink is vertically contacted or fixedly connected with the middle outer peripheral surface of the capacitor shell.

In one possible design, the number of the heat radiating fins is several and arranged at intervals in a circumferential direction on a middle outer peripheral surface of the capacitor case.

In one possible design, the heat dissipation fins are vertically or spirally arranged, the top surface of the first annular wall body is provided with a first notch matched with the bottom end of the heat dissipation fin, and the bottom surface of the second annular wall body is provided with a second notch matched with the top end of the heat dissipation fin;

the bottom of fin inserts in the first notch, the top of fin inserts in the second notch makes the fin is inlayed first annular wall body with between the second annular wall body.

In one possible design, the heat dissipation fins are arranged vertically or spirally, the horizontal cross sections of the heat dissipation fins are approximate to isosceles triangles or approximate isosceles trapezoids, wherein the bottom edges of the approximate isosceles triangles or the approximate isosceles trapezoids adopt line segments attached to the outer peripheral surface of the middle of the capacitor shell, and the side edges of the approximate isosceles triangles or the approximate isosceles trapezoids adopt inwards concave arc-shaped line segments.

In a possible design, still including the third sealing ring body, wherein, the third sealing ring body cover is in on insulation support's the periphery, be used for making insulation support passes the roof is right when the normal atmospheric temperature the second gas receiver seals, the third sealing ring body also by shape memory alloy makes, and raises the temperature to also can be through the deformation deblocking when predetermineeing the temperature the second gas receiver.

In a possible design, the first semi-surrounding body further comprises an extending ear plate integrally formed with the first annular wall body, wherein the extending ear plate is horizontally arranged and provided with a through hole for penetrating through the fixing piece;

the number of the extension ear plates is at least three and surrounds the bottom peripheral ring of the first ring wall body and is arranged at equal intervals.

In one possible design, the outer peripheral surface or the inner peripheral surface of the first sealing ring body and/or the second sealing ring body is deformed from a flat surface to a corrugated surface when the temperature is raised to the preset temperature, so that an air leakage channel which is communicated up and down is formed.

In one possible design, the first air reservoir stores a first fire suppressing gas and the second air reservoir stores a second fire suppressing gas, wherein the first fire suppressing gas has a gas density at standard atmospheric pressure that is less than the air density and the second fire suppressing gas has a gas density at standard atmospheric pressure that is greater than the air density.

In one possible design, the shape memory alloy is an alloy with a two-way memory effect.

The invention has the technical effects that:

(1) The invention has created and provided a novel fire prevention design scheme of capacitor based on shape memory alloy and gas for putting out a fire, namely can be while raising the temperature to the preset temperature used for judging the condition of a fire from the room temperature on the one hand, utilize the shape memory alloy to have and deform with the temperature characteristic, unseal two upper and lower gas reservoirs through two upper and lower sealed ring bodies, and then can release the gas for putting out a fire voluntarily, realize the fire prevention and the purpose of putting out a fire in time, and because the gas storage capacity is far greater than the liquid storage capacity, can promote the fire extinguishing effect greatly, on the other hand because the peripheral surface of the middle part of the capacitor shell is exposed to the nothing and sheltered from, therefore can carry on the heat dissipation of the capacitor directly, and then can promote the working temperature of the device, lengthen the service life of the device;

(2) Meanwhile, the capacitor shell is generally formed by splicing a seamless cylinder body, a shell bottom plate and a shell top plate, so that the places most prone to insulating oil seepage are the bottom and the top of the capacitor shell, high-pressure fire extinguishing gas in an upper gas storage chamber and a lower gas storage chamber can be used for inhibiting insulating oil in the shell from seeping and extruding oil seepage gaps, external high-pressure fire extinguishing gas is difficult to enter the shell, the high-pressure capacitor can be prevented from being damaged, and the service life of a device is further prolonged;

(3) Because the gas leakage mouth that two upper and lower air reservoirs formed because of alloy deformation is relative from top to bottom, consequently can slow down air current diffusion velocity through the air current hedging effect when two upper and lower air reservoirs leak gas simultaneously, and then prolong the gaseous dwell time around the condenser of putting out a fire, further promote fire prevention effect.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic longitudinal sectional view of a fireproof power capacitor according to the present invention.

Fig. 2 is a schematic top view of the fireproof power capacitor according to the present invention.

Fig. 3 is a schematic cross-sectional view of a fireproof power capacitor according to the present invention.

In the above drawings: 1-a capacitor element; 2-a capacitor case; 20-insulating oil; 21-a housing floor; 22-housing top plate; 3-a capacitor electrode; 4-an insulating sleeve; 51-a first semi-enclosure; 511-a backplane; 512-a first circumferential wall body; 513 — a first notch; 514-epitaxial ear plate; 515-a via; 52-a second semi-enclosure; 521-a top plate; 522-a second circumferential wall; 61-a first sealing ring body; 62-a second sealing ring body; 63-a third seal ring body; 71-a first air reservoir; 72-a second air reservoir; 8-radiating fins.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. Specific structural and functional details disclosed herein are merely representative of exemplary embodiments of the invention. This invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein.

It will be understood that, although the terms first, second, etc. may be used herein to describe various objects, these objects should not be limited by these terms. These terms are only used to distinguish one object from another. For example, a first object may be referred to as a second object, and similarly, a second object may be referred to as a first object, without departing from the scope of example embodiments of the present invention.

It should be understood that, for the term "and/or" as may appear herein, it is merely an associative relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, B exists alone or A and B exist at the same time; for the term "/and" as may appear herein, which describes another associative object relationship, it means that two relationships may exist, e.g., a/and B, may mean: a exists singly or A and B exist simultaneously; in addition, for the character "/" that may appear herein, it generally means that the former and latter associated objects are in an "or" relationship.

Example one

As shown in fig. 1 to 3, the fireproof power capacitor provided in the present embodiment includes a capacitor element 1, a capacitor case 2, a capacitor electrode 3, and an insulating sleeve 4, wherein the capacitor element 1 is installed as a capacitor core in the capacitor case 2, the capacitor case 2 is filled with insulating oil 20, the capacitor electrode 3 is led out from the capacitor case 2 through the insulating sleeve 4, and the fireproof power capacitor further includes a first semi-enclosure 51, a second semi-enclosure 52, a first seal ring 61, and a second seal ring 62; the first semi-surrounding body 51 comprises a bottom plate 511 and a first annular wall body 512 which are of an integrated structure, the first semi-surrounding body 51 surrounds the bottom of the capacitor shell 2 to form a first air storage chamber 71 which is surrounded by the bottom plate 511, the first annular wall body 512 and the shell bottom plate 21 of the capacitor shell 2, the first sealing ring body 61 is sleeved on the periphery of the bottom of the capacitor shell 2 and is wrapped by the first annular wall body 512 and used for sealing the first air storage chamber 71 at normal temperature, wherein the first sealing ring body 61 is made of shape memory alloy and can unseal the first air storage chamber 71 through deformation when the temperature is raised to a preset temperature; the second semi-enclosure 52 comprises a top plate 521 and a second circumferential wall 522 which are integrated, the second semi-enclosure 52 encloses the top of the capacitor casing 2 to form a second air reservoir 72 enclosed by the top plate 521, the second circumferential wall 522 and the casing top plate 22 of the capacitor casing 2, the second sealing ring 62 is sleeved on the periphery of the top of the capacitor casing 2 and is wrapped by the second circumferential wall 522 and used for sealing the second air reservoir 72 at normal temperature, wherein the second sealing ring 62 is also made of the shape memory alloy and can be deformed to unseal the second air reservoir 72 when the temperature is raised to the preset temperature; the first air reservoir 71 and the second air reservoir 72 store fire extinguishing gas having a normal temperature pressure value higher than a standard atmospheric pressure, respectively.

As shown in fig. 1 to 3, in a specific structure of the fireproof power capacitor, the capacitor element 1, the capacitor case 2, the capacitor electrode 3 and the insulating sleeve 4 are respectively necessary components in a conventional power capacitor, for example, in order to facilitate heat dissipation of the capacitor, the capacitor case 2 is preferably a cylindrical case and made of an aluminum alloy material, and the insulating oil 20 is also a necessary insulating material in a conventional power capacitor; the structural relationship between them is also the existing structural relationship. The first semi-enclosure 51 is used for being sleeved on the bottom periphery of the capacitor shell 2 through the first sealing ring body 61 so as to form the first air storage chamber 71; the second semi-enclosure 52 is used for being sleeved on the top periphery of the capacitor shell 2 through the second sealing ring body 62 so as to form the second air storage chamber 72; the first semi-enclosure 51 and the second semi-enclosure 52 are made of a material that can be easily integrated into a single piece, such as glass or ceramic. The first sealing ring body 61 and the second sealing ring body 62 are respectively sealed in an annular manner, inner wall surfaces of the first sealing ring body and the second sealing ring body are respectively in contact with the outer peripheral surface of the capacitor shell 2, and outer wall surfaces of the first sealing ring body and the second sealing ring body are respectively in contact with inner wall surfaces of corresponding annular wall bodies (512, 522), so that the sealing effect of the air reservoir at normal temperature is ensured. The preset temperature may be set, but is not limited to, a firing point temperature of the capacitor or the ambient environment, such as 120 degrees celsius.

The Shape Memory Alloy (SMA) is a material which has a Shape Memory Effect (SME) through thermoelasticity, martensite phase transformation and inversion thereof and is composed of more than two metal elements, so that the first sealing ring body 61 and the second sealing ring body 62 can be deformed along with temperature, and when the temperature is raised from normal temperature to the preset temperature, the corresponding gas storage chambers (71, 72) are unsealed to release the fire extinguishing gas; the material of the shape memory alloy can be set according to the preset temperature and the needed deformation amount, for example, high-temperature SMA such as Ti-Ni-Pd alloy, ti-Ni-PT alloy, ni-Ti-Hf alloy, ni-Ti-Zr alloy and Cu-Al-Ni-Mn alloy which are suitable for deformation in the environment of 100-300 ℃ is selected. The fire extinguishing gas may be natural gas, such as any one or a mixture of helium, neon, nitrogen, argon, carbon dioxide, etc., or synthetic gas, such as heptafluoropropane gas; the normal temperature air pressure of the fire extinguishing gas can be determined according to the ratio of the volume of the required fire extinguishing action to the volume of the corresponding air storage chamber, for example, the volume of the air storage chamber is 1 liter, and the volume of the required fire extinguishing action is at least 1 cubic meter, so that the fire extinguishing gas with the normal temperature air pressure value of at least 1000 standard atmospheric pressures can be filled; the form of the fire extinguishing gas may be a completely gaseous state, or may be a partially gaseous state and a partially liquid state.

From this through the detailed structure description of above-mentioned fire prevention type power capacitor, a novel fire prevention design scheme of condenser based on shape memory alloy and for the gas of putting out a fire is provided, can heat up to the temperature of predetermineeing that is used for judging the condition of a fire by the normal atmospheric temperature on the one hand, utilize shape memory alloy to have and the characteristics that warp along with the temperature, two upper and lower gasometers are come the deblocking through two upper and lower sealed ring bodies, and then can initiatively release for the gas of putting out a fire, realize the purpose of preventing fires and in time putting out a fire, and because gaseous storage capacity is far greater than the liquid storage capacity, can promote fire extinguishing effects greatly, on the other hand is because the middle part peripheral surface of capacitor case opens up dew nothing shelters from, consequently can directly carry out the condenser heat dissipation, and then can promote device operating temperature, extension device life. Consider simultaneously capacitor case generally is formed by seamless barrel, casing bottom plate and the concatenation of casing roof for the place that insulating oil oozes appears most easily is the bottom and the top of capacitor case, consequently can also utilize the high-pressure fire-extinguishing gas in the two gas storages about to suppress the insulating oil in the casing and ooze, and extrude the oil leakage gap, make outside high-pressure fire-extinguishing gas also difficult to enter in the casing, and then still can avoid causing destruction to high-voltage capacitor, further extension device life. In addition, because the gas leakage mouth that two upper and lower air reservoirs formed because of alloy deformation is relative from top to bottom, consequently can slow down the air current diffusion velocity through the air current hedging effect when two upper and lower air reservoirs leak gas simultaneously, and then the extension is put out a fire with the dwell time around the condenser, further promotes fire prevention fire extinguishing effect.

Preferably, a heat sink 8 is further included, wherein the heat sink 8 is vertically contacted or fixedly connected with the outer peripheral surface of the middle part of the capacitor housing 2. As shown in fig. 1 and 3, the heat dissipation effect of the capacitor can be further improved by the arrangement of the heat sink 8. Specifically, the number of the heat dissipation fins 8 is several, and the heat dissipation fins 8 are arranged on the outer peripheral surface of the middle portion of the capacitor case 2 at intervals in the circumferential direction, as shown in fig. 3, 36 heat dissipation fins 8 are arranged at intervals in the circumferential direction.

Further preferably, the heat sink 8 is vertically or spirally arranged, the top surface of the first annular wall body 512 is provided with a first notch 513 matched with the bottom end of the heat sink 8, and the bottom surface of the second annular wall body 522 is provided with a second notch matched with the top end of the heat sink 8; the bottom end of the heat sink 8 is inserted into the first notch 513 and the top end of the heat sink 8 is inserted into the second notch, so that the heat sink 8 is embedded between the first circumferential wall 512 and the second circumferential wall 522. As shown in fig. 3, the heat sink 8 is vertically disposed and embedded between the first circumferential wall 512 and the second circumferential wall 522, so that the installation stability of the heat sink 8 can be ensured, and the heat sink 8 is prevented from falling off particularly when the heat sink 8 is vertically contacted with the middle outer circumferential surface of the capacitor case 2.

Further preferably, the heat dissipation fins 8 are vertically or spirally arranged, the horizontal cross section of each heat dissipation fin 8 is approximately an isosceles triangle or an approximately isosceles trapezoid, the bottom side of each approximately isosceles triangle or the approximately isosceles trapezoid is a line segment attached to the outer peripheral surface of the middle of the capacitor shell 2, and the side edge of each approximately isosceles triangle or the approximately isosceles trapezoid is an inward concave arc line segment. As shown in fig. 3, since the bottom side is a line segment that is attached to the middle outer peripheral surface of the capacitor case 2 (for example, when the capacitor case 2 has a cylindrical shape, the line segment is an arc-shaped line segment), it is possible to ensure a maximum contact area between the heat sink 8 and the middle outer peripheral surface of the capacitor case 2, and to ensure a high heat conduction effect therebetween. Meanwhile, the side edge adopts the concave arc-shaped line segment, so that the heat dissipation area and the heat dissipation effect can be further improved compared with a flat edge design. In addition, in the case where the horizontal cross section of the heat sink 8 is approximately an isosceles triangle or an approximately isosceles trapezoid, the first notch 513 and the second notch may be formed as dovetail grooves adapted to the first notch, so that the bottom end and the top end of the heat sink 8 can form a dovetail structure after being inserted into the dovetail grooves, thereby further improving the mounting stability of the heat sink 8.

Preferably, the gas storage device further comprises a third sealing ring body 63, wherein the third sealing ring body 63 is sleeved on the periphery of the insulating sleeve 4 and used for enabling the insulating sleeve 4 to penetrate through the top plate 521 and sealing the second gas storage chamber 72 at normal temperature, and the third sealing ring body 63 is also made of the shape memory alloy and can unseal the second gas storage chamber 72 through deformation when the temperature is raised to the preset temperature. Similarly, as shown in fig. 1, the third seal ring body 63 can be described in detail with reference to the first seal ring body 61 and the second seal ring body 62, so that the fire extinguishing gas can be released upward at the top plate 521 while the capacitor electrode 3 and the insulating sleeve 4 are led out, and the fire extinguishing action area is expanded.

Preferably, the first semi-surrounding body 51 further includes an extending ear plate 514 integrally formed with the first circumferential wall 512, wherein the extending ear plate 514 is horizontally disposed and provided with a through hole 515 for passing through the fixing member; the number of the outward extending ear plates 514 is at least three and is arranged around the bottom peripheral ring of the first ring-shaped wall body 512 at equal intervals. As shown in fig. 1 to 3, the number of the extension ear plates 514 is three, so that the first semi-enclosure body 51 and the whole fireproof power capacitor can be fixedly mounted based on a three-point fixing principle, which is convenient for practical use.

Preferably, the outer peripheral surface or the inner peripheral surface of the first sealing ring body 61 and/or the second sealing ring body 62 is deformed from a flat surface to a corrugated surface when the temperature is raised to the preset temperature, so as to form a vertically communicating air leakage channel. The crest lines in the corrugated surface can be vertically arranged or spirally arranged, so that the deformed wave troughs form the air leakage channel to achieve the purpose of releasing the fire extinguishing gas at high temperature. Furthermore, the deformed wave crests can further increase the static friction between the sealing ring body and the outer circumferential surface of the capacitor case 2 or the inner wall surface of the corresponding circumferential wall (512, 522), thereby preventing the component from falling.

Preferably, the first air reservoir 71 stores a first fire extinguishing gas having a gas density lower than that of air at normal atmospheric pressure, and the second air reservoir 72 stores a second fire extinguishing gas having a gas density higher than that of air at normal atmospheric pressure. Through the setting of aforementioned gas density relation, can make heavier second put out a fire with gas after the release suppress the light first for putting out a fire with gas down, further slow down the diffusion velocity of first for putting out a fire with gas, the extension is put out a fire with gas residence time around the condenser, further promotes fire prevention effect. Specifically, the first extinguishing gas is preferably any one of helium, neon, nitrogen, and the like, or a mixed gas thereof, and the second extinguishing gas is preferably any one of argon, carbon dioxide, and the like, or a mixed gas thereof.

Preferably, the shape memory alloy adopts an alloy with a two-way memory effect. It is limited through aforementioned material, can also make first sealing ring body 61 and/or second sealing ring body 62 accomplish to extinguish a fire and cool down to after the preset temperature, the gas receiver that self-sealing corresponds again, and then can avoid extravagant with the gas of putting out a fire to it uses to put out a fire and put out a fire to prepare for next time.

To sum up, adopt the fire prevention type power capacitor that this embodiment provided, have following technological effect:

(1) The embodiment provides a novel fireproof design scheme of a capacitor based on shape memory alloy and gas for fire extinguishing, namely, on one hand, when the temperature is raised to a preset temperature for judging fire occurrence from normal temperature, the characteristics of shape memory alloy and deformation along with the temperature are utilized, the upper and lower gas storage chambers are unsealed through the upper and lower sealing ring bodies, then the gas for fire extinguishing can be actively released, the purposes of fire prevention and timely fire extinguishing are realized, the fire extinguishing effect can be greatly improved because the gas storage capacity is far greater than the liquid storage capacity, on the other hand, because the peripheral surface of the middle part of the capacitor shell is exposed and uncovered, the heat dissipation of the capacitor can be directly carried out, the working temperature of a device can be improved, and the service life of the device is prolonged;

(2) Meanwhile, the capacitor shell is generally formed by splicing a seamless cylinder body, a shell bottom plate and a shell top plate, so that the places most prone to insulating oil seepage are the bottom and the top of the capacitor shell, high-pressure fire-extinguishing gas in an upper gas storage chamber and a lower gas storage chamber can be used for inhibiting the insulating oil in the shell from seeping and extruding an oil seepage gap, external high-pressure fire-extinguishing gas is difficult to enter the shell, the high-pressure capacitor can be prevented from being damaged, and the service life of a device is further prolonged;

(3) Because the upper and lower air storage chambers are opposite up and down because of the gas leakage port that the alloy deformation formed, consequently can slow down the air current diffusion velocity through the air current hedging effect when two air storage chambers leak gas simultaneously, and then prolong the dwell time of gaseous around the condenser of putting out a fire, further promote fire prevention fire extinguishing effect.

Finally, it should be noted that the present invention is not limited to the above alternative embodiments, and that various other forms of products can be obtained by anyone in light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.

Claims

1. A fireproof power capacitor comprises a capacitor element (1), a capacitor shell (2), a capacitor electrode (3) and an insulating sleeve (4), wherein the capacitor element (1) is used as a capacitor core and is arranged in the capacitor shell (2), insulating oil (20) is filled in the capacitor shell (2), and the capacitor electrode (3) is led out from the inside of the capacitor shell (2) through the insulating sleeve (4), and is characterized by further comprising a first semi-surrounding body (51), a second semi-surrounding body (52), a first sealing ring body (61) and a second sealing ring body (62);

the first semi-surrounding body (51) comprises a bottom plate (511) and a first annular wall body (512) which are of an integrated structure, the first semi-surrounding body (51) surrounds the bottom of the capacitor shell (2) to form a first air storage chamber (71) surrounded by the bottom plate (511), the first annular wall body (512) and a shell bottom plate (21) of the capacitor shell (2), and a first sealing ring body (61) is sleeved on the periphery of the bottom of the capacitor shell (2) and wrapped by the first annular wall body (512) and used for sealing the first air storage chamber (71) at normal temperature, wherein the first sealing ring body (61) is made of shape memory alloy and can be unsealed through deformation when the temperature is raised to a preset temperature;

the second semi-surrounding body (52) comprises a top plate (521) and a second annular wall body (522) which are of an integrated structure, the second semi-surrounding body (52) surrounds the top of the capacitor shell (2) to form a second air storage chamber (72) surrounded by the top plate (521), the second annular wall body (522) and the shell top plate (22) of the capacitor shell (2), the second sealing ring body (62) is sleeved on the periphery of the top of the capacitor shell (2) and is wrapped by the second annular wall body (522) and used for sealing the second air storage chamber (72) at normal temperature, wherein the second sealing ring body (62) is also made of the shape memory alloy and can unseal the second air storage chamber (72) through deformation when the temperature is raised to the preset temperature;

the first air storage chamber (71) and the second air storage chamber (72) respectively store fire extinguishing gas with the normal-temperature air pressure value higher than the standard atmospheric pressure.

2. A fire-safe power capacitor according to claim 1, further comprising a heat sink (8), wherein the heat sink (8) is in vertical contact with the central peripheral surface of the capacitor case (2).

3. A fire-safe power capacitor according to claim 2, characterized in that the number of the heat radiating fins (8) is several and arranged at an interval in the circumferential direction on the middle outer circumferential surface of the capacitor case (2).

4. The fireproof power capacitor according to claim 2, wherein the heat sink (8) is spirally arranged, the top surface of the first annular wall (512) is provided with a first notch (513) matched with the bottom end of the heat sink (8), and the bottom surface of the second annular wall (522) is provided with a second notch matched with the top end of the heat sink (8);

the bottom end of the heat sink (8) is inserted into the first slot (513) and the top end of the heat sink (8) is inserted into the second slot, so that the heat sink (8) is embedded between the first circumferential wall (512) and the second circumferential wall (522).

5. The fire-proof power capacitor according to claim 2, wherein the heat dissipating fins (8) are spirally arranged, and the horizontal cross section of the heat dissipating fins (8) is approximately an isosceles triangle or an approximately isosceles trapezoid, wherein the bottom side of the approximately isosceles triangle or the approximately isosceles trapezoid is a line segment attached to the outer peripheral surface of the middle portion of the capacitor case (2), and the side of the approximately isosceles triangle or the approximately isosceles trapezoid is an inwardly concave arc line segment.

6. The fire-proof power capacitor according to claim 1, further comprising a third sealing ring body (63), wherein the third sealing ring body (63) is fitted around the outer periphery of the insulating sleeve (4) to allow the insulating sleeve (4) to pass through the top plate (521) and seal the second air storage chamber (72) at normal temperature, and the third sealing ring body (63) is also made of the shape memory alloy and is also deformed to unseal the second air storage chamber (72) when the temperature is raised to the predetermined temperature.

7. The fire-resistant power capacitor according to claim 1, wherein the first semi-enclosure (51) further comprises an extension ear plate (514) integrally formed with the first circumferential wall (512), wherein the extension ear plate (514) is horizontally disposed and has a through hole (515) for passing through a fixing member;

the number of the extending ear plates (514) is at least three and the extending ear plates are arranged around the periphery of the bottom of the first annular wall body (512) at equal intervals.

8. The fire-protected power capacitor according to claim 1, wherein an outer peripheral surface or an inner peripheral surface of the first sealing ring body (61) and/or the second sealing ring body (62) is deformed from a flat surface to a corrugated surface at the time of raising the temperature to the preset temperature, so as to form a leak passage communicating up and down.

9. The flameproof power capacitor of claim 1, wherein the first gas storage chamber (71) stores a first extinguishing gas, and the second gas storage chamber (72) stores a second extinguishing gas, wherein the first extinguishing gas has a gas density at normal atmospheric pressure lower than that of air, and the second extinguishing gas has a gas density at normal atmospheric pressure higher than that of air.

10. A fire-safe power capacitor as claimed in claim 1, wherein the shape memory alloy is an alloy having a two-way memory effect.