CN118431024A - Vacuum arc extinguishing chamber - Google Patents

Abstract

The application relates to the technical field of vacuum circuit breakers, and particularly discloses a vacuum arc extinguishing chamber, which comprises: the device comprises an arc extinguishing chamber shell, a first contact, a second contact, a first conducting rod, a second conducting rod, a radiating pipe and a ring magnet; the first conducting rod can slide and extend into the arc extinguishing chamber shell; the second conducting rod is fixed in the arc-extinguishing chamber shell, the inner end of the second conducting rod stretches into the arc-extinguishing chamber shell, and the outer end of the second conducting rod is positioned outside the arc-extinguishing chamber shell; the first contact is arranged at the inner end of the first conducting rod; the second contact is arranged at the inner end of the second conducting rod; the first conductive rod is used for driving the second contact and the first contact to contact each other or be far away from each other; the radiating pipe is arranged on the second conducting rod; the radiating pipes are connected end to end; the radiating pipe is internally provided with liquid metal; the ring magnet is arranged at the outer end of the second conducting rod. The annular magnet can drive the liquid metal to circulate in the radiating pipe so as to radiate the heat of the conducting rod to the outside of the shell of the arc extinguishing chamber in the moving process of the conducting rod.

Description

Vacuum arc extinguishing chamber

Technical Field

The application relates to the technical field of vacuum circuit breakers, in particular to a vacuum arc-extinguishing chamber.

Background

At present, the types of circuit breakers in a power system are mainly SF ₆ circuit breakers and vacuum circuit breakers; because SF ₆ gas has good thermal stability and electronegativity, the gas is widely used in the fields of high voltage and ultrahigh voltage. However, SF ₆ gas is not friendly to the environment because it has a strong greenhouse effect. In comparison, the vacuum circuit breaker has the advantages of minimal environmental pollution, meeting the environmental protection requirement, long mechanical life, compact size, light weight, low noise, simple maintenance and the like, and is widely applied to the field of medium-voltage 3.6-40.5 kV power switches.

Although the vacuum breaking technology is dominant in medium voltage class, the application of the vacuum breaking technology to high voltage class faces a series of technical challenges, wherein the problems include excessive contact temperature of the vacuum breaker when large current is broken, especially when the large current is broken, the phenomenon that the internal temperature of the vacuum breaker is increased by exceeding the standard easily can directly influence the safe and stable operation of equipment, meanwhile, the dielectric loss of an insulating part is increased, the aging of the insulating part is accelerated to cause the reduction of the insulating class, and the insulation failure of the vacuum breaker is caused when the serious condition happens.

Meanwhile, the high temperature of the circuit breaker can cause softening of contact materials, contact fusion welding is caused when the temperature is severe, the circuit breaker is likely to be broken and failed, the surface of a conductor metal is oxidized, the generated oxide increases the contact resistance to influence the loop resistance of the circuit breaker, heat is further increased, and the circuit breaker is burnt or even exploded when the temperature is severe.

Disclosure of Invention

In view of the above, the present application is directed to a vacuum interrupter for improving the heat dissipation effect of a vacuum circuit breaker.

In order to achieve the above technical object, the present application provides a vacuum interrupter, comprising: the device comprises an arc extinguishing chamber shell, a first contact, a second contact, a first conducting rod, a second conducting rod, a radiating pipe and a ring magnet;

The first conducting rod can extend into the arc extinguishing chamber shell in a sliding manner;

The second conducting rod is fixed in the arc-extinguishing chamber shell, the inner end of the second conducting rod stretches into the arc-extinguishing chamber shell, and the outer end of the second conducting rod is positioned outside the arc-extinguishing chamber shell;

The first contact is arranged at the inner end of the first conducting rod;

the second contact is arranged at the inner end of the second conducting rod;

the first conductive rod is used for driving the second contact and the first contact to contact or be far away from each other;

the radiating pipe is arranged on the second conducting rod;

The radiating pipe is of a circulating pipe structure connected end to end;

The radiating pipe is internally provided with liquid metal capable of circularly flowing along the radiating pipe;

The annular magnet is arranged at the outer end of the second conducting rod and is used for driving the liquid metal to circularly flow in the radiating pipe.

Further, a one-way valve is arranged in the radiating pipe.

Further, the one-way valve is a tesla valve.

Further, the radiating pipes comprise a plurality of radiating pipes and are symmetrically distributed around the axis of the second conducting rod.

Further, the radiating pipe extends to the second end of the second conductive rod along the first end of the second conductive rod.

Further, the plane where the ring magnet is located is perpendicular to the extending direction of the radiating pipe.

Further, both ends of the radiating pipe along the length direction are arc-shaped.

Further, the device also comprises a corrugated pipe;

the corrugated pipe is arranged in the arc extinguishing chamber shell;

The first contact is sleeved in the corrugated pipe.

Further, the device also comprises a shielding cover;

the shielding cover is arranged in the arc extinguishing chamber shell and sleeved on the radial periphery of the first contact and the radial periphery of the second contact.

Further, the annular magnet is a neodymium-iron-boron magnet permanent magnet.

From the above technical solution, the present application provides a vacuum arc extinguishing chamber, including: the device comprises an arc extinguishing chamber shell, a first contact, a second contact, a first conducting rod, a second conducting rod, a radiating pipe and a ring magnet; the first conducting rod can extend into the arc extinguishing chamber shell in a sliding manner; the second conducting rod is fixed in the arc-extinguishing chamber shell, the inner end of the second conducting rod stretches into the arc-extinguishing chamber shell, and the outer end of the second conducting rod is positioned outside the arc-extinguishing chamber shell; the first contact is arranged at the inner end of the first conducting rod; the second contact is arranged at the inner end of the second conducting rod; the first conductive rod is used for driving the second contact and the first contact to contact or be far away from each other; the radiating pipe is arranged on the second conducting rod; the radiating pipe is of a circulating pipe structure connected end to end; the radiating pipe is internally provided with liquid metal capable of circularly flowing along the radiating pipe; the annular magnet is arranged at the outer end of the second conducting rod and is used for driving the liquid metal to circularly flow in the radiating pipe.

In this scheme, annular magnet can drive liquid metal at the intraductal circulation flow of cooling tube to the heat of conducting rod looses the outside to the explosion chamber shell at the in-process that the conducting rod removed, thereby realizes effectively having promoted vacuum circuit breaker's radiating effect.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a vacuum arc extinguishing chamber according to an embodiment of the present application;

fig. 2 is a schematic diagram of internal heat of a vacuum arc-extinguishing chamber according to an embodiment of the present application;

fig. 3 is a schematic diagram of a vacuum interrupter ring magnet driving liquid metal to flow according to an embodiment of the present application;

fig. 4 is a schematic diagram of a ring magnet and a radiating pipe of a vacuum arc-extinguishing chamber according to an embodiment of the present application;

fig. 5 is a schematic forward flow diagram of a tesla valve of a vacuum arc-extinguishing chamber according to an embodiment of the present application;

Fig. 6 is a schematic diagram of reverse flow of a tesla valve of a vacuum arc-extinguishing chamber according to an embodiment of the present application;

In the figure: 10. an arc extinguishing chamber housing; 21. a first contact; 22. a second contact; 31. a first conductive rod; 32. a second conductive rod; 40. a heat radiating pipe; 50. a ring magnet; 60. a bellows; 70. a shield;

a. A thermal mass; I. current in the conductive rod; B. a magnetic field component in which a magnetic field generated by the ring magnet is perpendicular to the current direction; F. ampere force; s, S poles; n, N poles.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments disclosed in the specification without making any inventive effort, are intended to be within the scope of the application as claimed.

In the description of the embodiments of the present application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the embodiments of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the embodiments of the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In describing embodiments of the present application, it should be noted that, unless explicitly stated and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, interchangeably connected, integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected through an intermediary, or in communication between two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art in a specific context.

Referring to fig. 1 and 2, a vacuum interrupter provided in an embodiment of the application can be used as a vacuum circuit breaker, and includes: the arc extinguishing chamber housing 10, the first contact 21, the second contact 22, the first conductive rod 31, the second conductive rod 32, the radiating pipe 40, and the ring magnet 50.

In this embodiment, the second contact 22 is used as a stationary contact, and is fixedly disposed in the arc extinguishing chamber housing 10. In particular, the second conductive rod 32 to which the second contact 22 is connected may be fixed within the arc chute housing 10. Correspondingly, the first contact 21 is a moving contact. The first conductive rod 31 to which the first contact 21 is connected may be sleeved on the bellows 60; the bellows 60 is fixedly disposed at one end within the arc chute housing 10. In the orientation shown in fig. 1, the bellows 60 is secured to the bottom end of the interior of the arc chute housing 10.

The first conductive rod 31 is slidably disposed on the arc chute housing 10. In the orientation shown in fig. 1, a first conductive rod 31 is slidably disposed at the bottom end of the arc chute housing 10. The inner part of the first conductive rod 31 extends into the arc extinguishing chamber housing 10, and the outer end of the first conductive rod 31 is positioned outside the arc extinguishing chamber housing 10. The first contact 21 is provided at the inner end of the first conductive rod 31. The second contact 22 is disposed at the inner end of the second conductive rod 32. Similarly, the inner end of the second conductive rod 32 is the end thereof that extends into the arc chute housing 10.

The first conductive rod 31 is slidably disposed on the arc extinguishing chamber housing 10; in the orientation shown in fig. 1, the first conductive rod 31 can slide up and down in the vertical direction in the arc chute housing 10, thereby bringing the second contact 22 and the first contact 21 into contact with each other or away from each other. Wherein the second contact 22 is arranged coaxially with the first contact 21.

The radiating pipe 40 is disposed on the second conductive rod 32; the radiating pipe 40 is a circulating pipe structure connected end to end; the heat radiating pipe 40 is internally provided with liquid metal which can circularly flow along the heat radiating pipe 40; the ring magnet 50 is disposed at the outer end of the second conductive rod 32 for driving the liquid metal to circulate in the radiating pipe 40.

The inventor finds that, in practical application, the loop resistance of the vacuum circuit breaker is a main heat source affecting temperature rise, and the loop resistance of the arc extinguishing chamber generally accounts for more than 50% of the loop resistance of the vacuum circuit breaker. The contact gap contact resistance is a main component of the loop resistance of the vacuum arc-extinguishing chamber, because the contact system is sealed in the vacuum arc-extinguishing chamber, and the generated heat can only dissipate to the outside through the conducting rod. In addition, due to the special structure of the vacuum circuit breaker, the heat transfer mode with the highest effectiveness in the vacuum arc-extinguishing chamber is heat conduction through the conducting rod, the effect of heat convection heat transfer is smaller, the heat dissipation effect of heat radiation heat transfer is not obvious, and for the vacuum circuit breaker with high voltage level, the heat conduction/heat conduction path of the vacuum arc-extinguishing chamber is longer due to the consideration of vacuum insulation, and the heat generation of the circuit breaker is more serious and is unfavorable for heat conduction and heat dissipation.

In this embodiment, the second conductive rod 32 capable of extending out of the arc extinguishing chamber housing 10 is used as a main heat dissipation path, the heat dissipation pipe 40 is provided on the second conductive rod 32, and the heat mass a flowing in the heat dissipation pipe 40 is guided to the outer end of the second conductive rod 32 to be dissipated out of the arc extinguishing chamber housing 10 by the liquid metal flowing in the heat dissipation pipe 40.

In this scheme, adopt liquid metal as circulative cooling heat dissipation medium, liquid metal has higher coefficient of heat conductivity, low viscosity, good electric conductivity and stable physical property, for traditional forced air cooling system and liquid cooling system, has better heat dissipation ability to can show the radiating efficiency who improves second conducting rod 32 in the vacuum interrupter, can effectively solve the problem that high voltage class vacuum circuit breaker internal temperature rise is too high, this technique can also be applied in generator export protection circuit breaker in addition.

In particular, the liquid metal may be a non-toxic low melting point metal mixture that melts to a liquid state at room temperature, the composition of which includes a portion of the low melting point metal, such as gallium or indium. The liquid metal has unique physical properties, not only has the fluidity of liquid, but also has the excellent heat conduction performance of metal, the heat conductivity of the liquid metal is generally in the order of 10 W.m < -1 >. K < -1 >, and is 50 times of that of water, and more than 1000 times of that of air, so that the liquid metal has good convection heat exchange capacity. The liquid metal also has high conductivity properties as a metal mixture, and has little effect on the conductivity of the second conductive rod 32 and the resistance value of the conductive loop. Meanwhile, the liquid metal has high boiling point, large surface tension, low saturated steam pressure, and is safer and more stable than water cooling, which is less prone to boiling, leakage and evaporation. The density of the liquid metal is high, a large amount of nano particles can be accommodated, carbon nano tubes, three typical high-thermal-conductivity metal nano particles (gold, silver, copper) and the like can be added into the liquid metal, the physical properties such as the thermal conductivity of the liquid metal are further enhanced, and the liquid metal has better adaptability. The novel heat dissipation system using liquid metal as a heat transfer medium has better heat dissipation capacity, safer structure and material property and more efficient circulation system compared with the traditional air cooling heat dissipation system and liquid cooling heat dissipation system due to higher heat conductivity coefficient, low viscosity and stable physical property.

Considering that the vacuum circuit breaker has smaller internal space and higher insulation requirement, the invention is not suitable for adopting a traditional active pump as a device for driving cooling medium to circularly flow in the cooling tube, so the annular magnet 7 is arranged at the end part of the second conducting rod 32 to realize passive driving of liquid metal to circularly flow in the liquid cooling tube 6. In this embodiment, the principle of the annular magnet 50 driving the liquid metal to circulate in the annular radiating pipe 40 is shown in fig. 3, where S represents that the top surface of the annular magnet 50 is the S pole; n in the figure indicates that the bottom surface of the ring magnet 50 is an N pole; arrow I in the figure refers to the direction of current flow in the second conductive rod 32; arrow B in the figure indicates a magnetic field component perpendicular to the current direction of the magnetic field generated by the ring magnet 50; arrow F is the direction of the ampere force.

Specifically, in operation of the vacuum interrupter, an axial current is passed through the second conductive rod 32 while the current is passed through the liquid metal in the radiating pipe 40. The ring magnet 50 provided at the end of the second conductive rod 32 generates a magnetic field, and the magnetic field at the radiating pipe 40 near the end of the second conductive rod 32 is perpendicular to the current I direction in the radial direction, and the passive mode is realized by virtue of the ampere force F generated by the current in the second conductive rod 32 and the magnetic field of the ring magnet 50 to drive the liquid metal to circularly flow in the radiating pipe 40 along the ampere force F direction.

In practical applications, the radiating pipe 40 may be disposed inside the second conductive rod 32 by means of internal grooving, and then the liquid metal is injected into the grooves hollowed by the second conductive rod 32 to seal the grooves.

In this embodiment, the ring magnet 50 may be a neodymium-iron-boron permanent magnet. In order to secure the driving effect after the ring magnet 50 and the second conductive rod 32 are engaged, a plane in which the ring magnet 50 is located may be disposed to be perpendicular to the extending direction of the radiating pipe 40.

Specifically, the length direction of the second conductive rod 32 is the up-down direction in fig. 1. The radiating pipe 40 extends along the inner end of the second conductive rod 32 to the outer end of the second conductive rod 32; that is, the radiating pipe 40 extends in the up-down direction in fig. 1, and ensures the radiating area of the second conductive rod 32. The plane in which the ring magnet 50 is located is horizontal in the orientation shown in fig. 1, i.e., the ring magnet 50 is disposed horizontally; the axial center of the ring magnet 50 may be disposed coaxially with the second conductive rod 32, so that it is better ensured that the magnetic field generated by the ring magnet 50 can drive the liquid metal to flow in the radiating pipe 40.

In a further improved embodiment, please refer to fig. 4, a one-way valve 41 is disposed in the radiating pipe 40; the check valve 41 prevents the liquid metal from flowing backward, and ensures that the liquid metal flows in only one direction in the radiating pipe 40.

As one embodiment, the one-way valve 41 is a tesla valve. The number of tesla valves may be plural.

Specifically, as shown in fig. 5 and 6, the tesla valve adopts a special loop design, when the fluid (liquid metal) passes through the tesla valve in the forward direction, the fluid is divided into two paths at each loop port, and then the two paths of fluid are converged at the next junction port, and acceleration is realized. Conversely, if the fluid flows reversely into the tesla valve, the fluid is divided into two paths at the first junction and is converged again at the second junction, except that the flow directions of the two paths of fluid are opposite at this time, so that a great resistance is formed, and therefore, the tesla valve can only pass forward and is difficult to reverse flow. And moreover, the Tesla valve can play an acceleration effect on the liquid metal flowing in the forward direction, so that the heat exchange between the liquid metal and the outside is promoted.

When the vacuum circuit breaker works, because of the special structure of the Tesla valve, the resistance of the liquid metal flowing in the left radiating pipe and the right radiating pipe is different, the liquid metal in the radiating pipe is promoted to flow unidirectionally along the direction with small flowing resistance,

In one embodiment, a shield 70 is also included; the shield 70 is disposed in the arc extinguishing chamber housing 10 and is sleeved on the radial outer circumferences of the first contact 21 and the second contact 22. The shield 70 is disposed coaxially with the first contact 21 and the second contact 22.

To further enhance the heat dissipation effect, in one embodiment, the heat dissipation tubes 40 may include a plurality of heat dissipation tubes and be symmetrically distributed around the axis of the second conductive rod 32.

Further, both ends of the radiating pipe 40 along the length direction are arc-shaped, so that the shape of the radiating pipe 40 can be more effectively attached to the round rod-shaped second conducting rod 32, and meanwhile, the end radiating area of the radiating pipe 40 is increased.

The vacuum arc-extinguishing chamber provided by the invention realizes the driving of the liquid metal to circularly flow in the radiating pipe 40 by virtue of the current in the second conducting rod 32 and the ampere force generated by the magnetic field of the annular magnet 50, does not need to be additionally provided with an additional power driving device, is more suitable for a compact space inside the vacuum arc-extinguishing chamber, can not influence the insulation performance of the vacuum circuit breaker, and can absorb the heat energy of the second conducting rod 32 and the first contact 21 and the second contact 22 by taking the liquid metal as circulating cooling liquid, thereby achieving the purpose of reducing the temperature rise of the vacuum arc-extinguishing chamber, realizing the reduction of the temperature inside the vacuum circuit breaker, and avoiding the problems of accelerated ageing of an insulating part, softening of a contact material and explosion of the vacuum circuit breaker.

While the application has been described in detail with reference to the examples, it will be apparent to those skilled in the art that the foregoing description of the preferred embodiments of the application may be modified or equivalents may be substituted for elements thereof, and that any modifications, equivalents, improvements or changes will fall within the spirit and principles of the application.

Claims (10)

1. A vacuum interrupter, comprising: an arc extinguishing chamber housing (10), a first contact (21), a second contact (22), a first conductive rod (31), a second conductive rod (32), a radiating pipe (40) and a ring magnet (50);

The first conducting rod (31) can extend into the arc extinguishing chamber shell (10) in a sliding manner;

The second conducting rod (32) is fixed in the arc-extinguishing chamber shell (10), the inner end of the second conducting rod (32) stretches into the arc-extinguishing chamber shell (10), and the outer end of the second conducting rod (32) is positioned outside the arc-extinguishing chamber shell (10);

the first contact (21) is arranged at the inner end of the first conducting rod (31);

The second contact (22) is arranged at the inner end of the second conducting rod (32);

the first conducting rod (31) is used for driving the second contact (22) and the first contact (21) to be in contact with each other or away from each other;

The radiating pipe (40) is arranged on the second conducting rod (32);

the radiating pipe (40) is of a circulating pipe structure connected end to end;

The radiating pipe (40) is internally provided with liquid metal capable of circularly flowing along the radiating pipe (40);

the annular magnet (50) is arranged at the outer end of the second conducting rod (32) and is used for driving the liquid metal to circularly flow in the radiating pipe (40).

2. Vacuum interrupter according to claim 1, characterized in that a non-return valve (41) is arranged in the radiating pipe (40).

3. Vacuum interrupter according to claim 2, characterized in that the one-way valve (41) is a tesla valve.

4. The vacuum interrupter of claim 1 wherein said radiating tube (40) comprises a plurality and is symmetrically disposed about an axis of said second conductive rod (32).

5. The vacuum interrupter of claim 1, wherein the radiating tube (40) extends along an inner end of the second conductive rod (32) to an outer end of the second conductive rod (32).

6. The vacuum interrupter according to claim 5, wherein the plane of the ring magnet (50) is perpendicular to the extending direction of the radiating pipe (40).

7. The vacuum interrupter of claim 6, wherein both ends of the radiating pipe (40) in the length direction are arc-shaped.

8. The vacuum interrupter of claim 1, further comprising a bellows (60);

the corrugated pipe (60) is arranged in the arc extinguishing chamber shell (10);

the first contact (21) is sleeved in the corrugated pipe (60).

9. The vacuum interrupter of claim 1, further comprising a shield (70);

the shield cover (70) is arranged in the arc extinguishing chamber shell (10) and sleeved on the radial peripheries of the first contact (21) and the second contact (22).

10. Vacuum interrupter according to claim 1, characterized in that the ring magnet (50) is a neodymium-iron-boron magnet permanent magnet.