CN116995497A - Busbar assembly and closed combined electrical apparatus - Google Patents

Abstract

The application relates to the technical field of conductors, in particular to a busbar assembly and a closed combined electrical appliance, wherein the busbar assembly comprises 4 conductors with the same shape, and the conductors are of a cuboid structure; the length directions of the 4 electric conductors are parallel to each other; the first maximum surfaces of the 4 electric conductors are respectively attached to 4 side surfaces of the prismatic space, and the bottom surface of the prismatic space is diamond-shaped; the edge of the prismatic space is spaced from the first maximum surface; the first largest surface of two adjacent conductors is equally spaced from the adjacent edge; the 4 conductors are connected in parallel. The gas between 4 conductors and the gas outside 4 conductors can form smooth backflow, so that effective heat dissipation can be achieved on each surface of the conductors through natural convection, the effective heat dissipation area is increased, the heat dissipation effect is remarkably improved, the temperature rise inside the GIS can be effectively reduced through the busbar assembly connected with each element in the GIS, and normal operation of the GIS is ensured.

Description

Busbar assembly and closed combined electrical apparatus

Technical Field

The application relates to the technical field of conductors, in particular to a busbar assembly and a closed type combined electrical appliance.

Background

The closed combined electric appliance, GIS (Gas Insulatde Switchegear), also called gas-insulated switch, combines all equipment except transformer in a transformer substation, including circuit breaker, isolating switch, earthing switch, CT, PT, bus arrester in-out sleeve, etc. into a whole organically by optimizing design. The GIS effectively reduces the occupied area, and all elements are sealed and not interfered by the environment, so that the GIS has the advantages of high operation reliability, convenience in operation, long maintenance period, small maintenance workload, rapidness in installation, low operation cost, no electromagnetic interference and the like.

In order to achieve the miniaturization of the GIS, the treatment of the problems of heat generation and heat dissipation inside the high-voltage GIS is an important issue. The main degradation factors of the high voltage switchgear can be divided into: although there are few phenomena caused by thermal degradation alone, various adverse effects are often caused by thermal degradation in combination with other factors. Therefore, once the internal components, parts, materials and the like of the switch cabinet exceed the allowable temperature use range, the performance cannot be ensured, misoperation can occur, the service life (10 ℃ halving rule) is shortened, and the reliability of the GIS is obviously reduced. For example: the SF6 distribution is uneven due to the fact that the through current temperature of the bus is increased, the SF6 distribution is thinner in the area with higher temperature rise, the insulation level is lowered more greatly, insulation damage can be caused by overheating of a high-voltage current conductor in the switch cabinet, and accordingly main insulation breakdown occurs due to discharge, equipment damage and user power failure are caused. Therefore, in the development process of GIS equipment, the temperature rise condition is fully considered, and the temperature rise rule is researched, so that the GIS design scheme is optimized, and the method has important engineering application value.

The excessive internal temperature rise of the GIS is a problem needing to comprehensively consider multiple factors, and the two main reasons are that under the condition of long-term through-flow high current, a large amount of joule heat is generated by the resistance of the conducting loop wire and the larger contact resistance of the bus connection part, so that overheating is caused; and secondly, due to poor heat dissipation conditions, heat generated on the lead cannot be dissipated in time, so that the heat is accumulated on the surface of the conductor, and the temperature rise value of the surface of the conductor is too high. Heat dissipation is achieved primarily by natural convection of the gas surrounding the bus bar by radiating heat outwards through the conductors. The common material of the GIS inner conductor is copper, the surface emissivity of the GIS inner conductor is about 0.03, and the heat radiation effect from the heat radiation to the outside is very limited.

Disclosure of Invention

The application provides a busbar assembly and a closed combined electrical appliance, which are used for solving the technical problems that in the prior art, a busbar dissipates heat through outward radiation and natural convection, the heat dissipation effect is very limited, so that the internal temperature rise of a GIS is too high, and the operation is influenced.

The first aspect of the present application provides a busbar assembly, which includes:

4 pieces of electric conductors with the same shape, wherein the electric conductors are of cuboid structures;

the length directions of the 4 pieces of the conductors are parallel to each other;

the first maximum surfaces of the 4 pieces of the electric conductors are respectively attached to 4 side surfaces of the prismatic space, and the bottom surface of the prismatic space is diamond-shaped;

the edge of the prismatic space is spaced from the first maximum surface;

the first maximum surfaces of two adjacent conductors are equally spaced from the adjacent edge;

4 of the conductors are connected in parallel.

In a first possible implementation of the busbar assembly according to the first aspect, a minimum spacing between two adjacent conductors is d;

the thickness of the conductor is a;

d＞0.9a。

with reference to the first possible busbar assembly of the first aspect, in a second possible busbar assembly of the first aspect, an included angle formed by the first largest surface and an bisecting section of the prismatic space is α, where the bisecting section is a plane in which 2 non-adjacent edges of the prismatic space are located;

30°≤α≤50°。

in combination with the busbar assembly provided in the first aspect, the busbar assembly possible in the first aspect, or the busbar assembly possible in the second aspect, in a third possible busbar assembly possible in the first aspect, the busbar assembly further includes:

a cylindrical insulator;

4 pieces of the electric conductors are arranged in the insulator;

a space exists between the conductor and the inner peripheral surface of the insulator;

the insulator is coaxial with the prismatic space.

With reference to the third possible busbar assembly of the first aspect, in a fourth possible busbar assembly of the first aspect, the busbar assembly further includes:

a first bus-bar clamp and a second bus-bar clamp;

one end of the 4 electric conductors in the length direction is fixed in the insulator through the first bus bar clamp, and the other end is fixed in the insulator through the second bus bar clamp.

With reference to the fourth possible busbar assembly of the first aspect, in a fifth possible busbar assembly of the first aspect, the first busbar clamp is a circular flat plate structure with a diameter equal to an inner diameter of the insulator;

the first bus-bar clamp is provided with 1 first round through hole and 4 square through holes which extend along the axial direction;

the axis of the first circular through hole is collinear with the axis of the first bus-bar clamp;

the conductor is matched with the square through hole in a penetrating way;

the second bus bar clamp is of a cylindrical structure with the diameter equal to the inner diameter of the insulator;

the bottom surface of the second bus-bar clamp is provided with a groove extending along the axial direction, and the radial section of the groove is diamond-shaped;

the bottom wall of the groove is provided with a second circular through hole extending along the axial direction, and the axis of the second circular through hole is collinear with the axis of the second bus clamp;

the second largest surfaces of the 4 pieces of the electric conductors are respectively attached to the 4 side walls of the groove;

the outer peripheral surfaces of the first bus bar clamp and the second bus bar clamp are attached to the inner peripheral surface of the insulator.

With reference to the fifth possible busbar assembly of the first aspect, in a sixth possible busbar assembly of the first aspect, the busbar assembly further includes;

watchband contact fingers arranged on the side wall of the groove;

the watchband contact finger is abutted with the second maximum surface.

In combination with the busbar assembly of the first aspect, the first possible busbar assembly of the first aspect or the second possible busbar assembly of the first aspect, in a seventh possible busbar assembly of the first aspect, the electrical conductor is made of copper.

The second aspect of the present application provides a closed type combined electrical apparatus, comprising:

a metal can and any one of the possible busbar assemblies provided in the first aspect;

the busbar assembly is arranged in the metal cylinder.

In the first possible implementation manner of the second aspect, the closed type combined electrical apparatus further includes:

the circuit breaker, the isolating switch, the voltage transformer and the current transformer are arranged in the metal cylinder;

the circuit breaker, the isolating switch, the voltage transformer and the current transformer are mutually connected through the busbar assembly.

From the above technical scheme, the application has the following advantages:

the busbar assembly provided by the application comprises 4 conductors with the same shape, wherein the conductors are of a cuboid structure; the length directions of the 4 electric conductors are parallel to each other; the first maximum surfaces of the 4 electric conductors are respectively attached to 4 side surfaces of the prismatic space, and the bottom surface of the prismatic space is diamond-shaped; the edge of the prismatic space is spaced from the first maximum surface; the first largest surface of two adjacent conductors is equally spaced from the adjacent edge; the 4 conductors are connected in parallel. Through fixing 4 electric conductors at intervals on 4 sides of prismatic type space that the bottom surface is diamond-shaped, the gas that is located between 4 electric conductors and the gas that is located outside 4 electric conductors can form smooth and easy backward flow, so, each surface of electric conductor all accessible natural convection realizes effective heat dissipation, effective heat dissipation area increases, the heat dissipation effect is showing and promotes, connects each component in the GIS through this busbar subassembly, can effectively reduce the inside temperature rise of GIS, ensures GIS normal operating.

Meanwhile, the arrangement mode of 4 conductors in the busbar assembly can avoid the generation of skin effect, the current density is distributed uniformly, the heating value is small, and the temperature rise is further reduced.

In addition, the arrangement mode of 4 conductors can well utilize the space position, so that the busbar assembly is more compact and occupies small space.

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 view of a single round tube busbar in the prior art;

FIG. 2 is a flow field diagram of a single round tube busbar in the prior art when a large current is conducted;

FIG. 3 is a schematic structural diagram of a busbar assembly according to an embodiment of the present application;

FIG. 4 is a schematic diagram of another embodiment of a busbar assembly;

FIG. 5 is a schematic diagram of a partial structure of a busbar assembly according to an embodiment of the present application;

FIG. 6 is a schematic diagram of another partial structure of a busbar assembly according to an embodiment of the present application;

FIG. 7 is a schematic diagram of another partial structure of a busbar assembly according to an embodiment of the present application;

FIG. 8 is a schematic diagram of another partial structure of a busbar assembly according to an embodiment of the present application;

FIG. 9 is a flow field diagram of a busbar assembly according to an embodiment of the present application when a large current is applied;

FIG. 10 is a graph showing a current density distribution of a busbar assembly according to an embodiment of the present application;

wherein:

1. conductor 2, insulator 3 and first bus bar clamp

31. First circular through hole 32, square through hole 4 and second bus bar clamp

41. Groove 42, second circular through hole 5, watchband contact finger.

Detailed Description

The embodiment of the application provides a busbar assembly and a closed combined electrical appliance, which are used for solving the technical problems that in the prior art, a busbar dissipates heat through outward radiation and natural convection, and the heat dissipation effect is very limited, so that the internal temperature rise of a GIS is too high, and the operation is influenced.

In order to make the objects, features and advantages of the present application more obvious and understandable, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the embodiments described below are only some embodiments of the present application, not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

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 embodiments of the present application will be understood in detail by those of ordinary skill in the art.

The excessive internal temperature rise of the GIS is a problem needing to comprehensively consider multiple factors, and the two main reasons are that under the condition of long-term through-flow high current, a large amount of joule heat is generated by the resistance of the conducting loop wire and the larger contact resistance of the bus connection part, so that overheating is caused; and secondly, due to poor heat dissipation conditions, heat generated on the lead cannot be dissipated in time, so that the heat is accumulated on the surface of the conductor, and the temperature rise value of the surface of the conductor is too high. Heat dissipation is achieved primarily by natural convection of the gas surrounding the bus bar by radiating heat outwards through the conductors. The common material of the GIS inner conductor is copper, the surface emissivity of the GIS inner conductor is about 0.03, and the heat radiation effect from the heat radiation to the outside is very limited.

Referring to fig. 1-10, a busbar assembly according to an embodiment of the present application includes:

4 pieces of electric conductors 1 with the same shape, wherein the electric conductors 1 are of cuboid structures; the length directions of the 4 electric conductors 1 are parallel to each other; the first maximum surfaces of the 4 electric conductors 1 are respectively attached to 4 side surfaces of the prismatic space, and the bottom surface of the prismatic space is diamond-shaped; the edge of the prismatic space is spaced from the first maximum surface; the first largest surface of two adjacent conductors 1 is equally spaced from the adjacent edge; 4 conductors 1 are connected in parallel.

It should be noted that:

the first maximum surface is any one of 12 maximum surfaces of the conductor, and the other maximum surface is the second maximum surface.

The edge of the prismatic space is spaced from the first maximum surface, i.e. the width of the first maximum surface is smaller than the width of the side surface of the prismatic space, the conductor 1 is positioned between two long edges of the side surface, and a space is reserved between the two long edges; the first largest surface of two adjacent conductors 1 is equally spaced from the adjacent edge, i.e. the conductors 1 on either side of any edge of the prismatic space are symmetrical about that edge.

The 4 conductors 1 are connected in parallel, so that the current flowing through each conductor 1 is the same.

The beneficial effects of this embodiment include:

(1) through fixing 4 electric conductors 1 interval on the prismatic space's that the bottom surface is diamond 4 sides, be located the gas between 4 electric conductors 1 and be located the gas outside 4 electric conductors 1 and can form smooth and easy backward flow, so, each surface of electric conductor 1 all accessible natural convection realizes effective heat dissipation, effective heat dissipation area increases, the heat dissipation effect is showing and promotes, connect each component in the GIS through this busbar subassembly, can effectively reduce the inside temperature rise of GIS, ensure GIS normal operating.

(2) The arrangement mode of the 4 conductors 1 in the busbar assembly can avoid the generation of skin effect, the current density is distributed uniformly, the heating value is small, and the temperature rise is further reduced.

(3) The arrangement mode of the 4 electric conductors 1 can well utilize the space position, so that the busbar assembly is more compact and occupies small space.

(4) The arrangement mode of the 4 conductors 1 is simple, and the electric conductor can be flexibly applied to flowing large current in other closed spaces, and has universality.

Specific: the flow field structure diagrams of the busbar assembly and the single round tube busbar with large current in a long term are shown in fig. 2 and 9 respectively, and it can be seen from the figures that the gas inside and outside the conductor 1 in the busbar assembly forms smooth reflux, the gas inside the single round tube busbar hardly flows, the effective radiating surface is only the outer peripheral surface, compared with the two, the electrified section of the 4 conductors 1 is slightly smaller than that of the round tube busbar, the resistance is slightly increased, and more heat is generated, but the effective radiating area is increased by nearly one time due to the smooth reflux formed on the inner side and the outer side of the 4 conductors 1, the heat taken away is much more than the heat generated in a large amount, so that the temperature rise in the GIS is obviously reduced.

An optimized arrangement of the electrical conductors 1: the minimum interval between two adjacent conductors 1 is d; the thickness of the conductor 1 is a; d > 0.9a; the thickness of the electrical conductor 1 is b. Through tests, when d is more than 0.9a, the backflow of the gas between the 4 conductors 1 and the gas outside the 4 conductors 1 is smoother, the heat dissipation effect is better, and the fact that the circulation efficiency of the gas is in direct proportion to the size of the interval on the premise that d is more than 0.9a can be understood, so that a larger value can be properly taken under the condition that the space occupied by the 4 conductors 1 is not obviously increased, the gas flow is smoother, and the heat dissipation effect is improved.

Further optimized: the included angle formed by the first maximum surface and the equally divided section of the prismatic space is alpha, and the equally divided section is the plane where 2 non-adjacent edges of the prismatic space are located; alpha is more than or equal to 30 degrees and less than or equal to 50 degrees. Referring to fig. 5, it is tested that α varies within a range of 30 ° to 50 ° with d > 0.9a, and the heat dissipation effect varies slightly, but the influence is limited, i.e., α is within a range of 30 ° to 50 °, so that the internal and external gases can smoothly circulate to achieve the optimal heat dissipation effect, i.e., the accuracy required for arranging the conductor 1 is low, a certain amount of fault tolerance is provided, and the conductor 1 is flexible in design, easy to implement and has high implementation feasibility.

Specific: on the premise of ensuring d is more than 0.9a and 30 degrees is less than or equal to alpha is less than or equal to 50 degrees, in actual production, a thicker conductor 1 can be properly selected, so that the area of the electrified section of the conductor 1 is increased, the resistance of the conductor 1 is reduced, the heating value is reduced, the temperature rise can be further reduced, but the effect of further reducing the temperature rise by continuously increasing the thickness of the conductor is very limited due to the proximity effect of the conductor.

Optimizing: the busbar assembly is also provided with a cylindrical insulator 2;4 conductors 1 are arranged in the insulator 2; a space exists between the conductor 1 and the inner peripheral surface of the insulator 2; the insulator 2 is coaxial with the prismatic space.

Optimizing: the busbar assembly is also provided with a first busbar clamp 3 and a second busbar clamp 4; one end of the 4 electric conductors 1 in the length direction is fixed in the insulator 2 by the first bus bar clamp 3, and the other end is fixed in the insulator 2 by the second bus bar clamp 4.

Exemplary: as shown in fig. 7, the first bus bar clip 3 has a circular flat plate structure having a diameter equal to the inner diameter of the insulator 2; the first bus-bar clamp 3 is provided with 1 first circular through hole 31 and 4 square through holes 32 which extend along the axial direction; the axis of the first circular through hole 31 is collinear with the axis of the first bus bar clamp 3; the conductor 1 is adaptively arranged in the square through hole 32 in a penetrating way; the second bus bar clamp 4 is of a cylindrical structure with the diameter equal to the inner diameter of the insulator 2; as shown in fig. 8, the bottom surface of the second bus bar clamp 4 is provided with a groove 41 extending along the axial direction, and the radial section of the groove 41 is diamond-shaped; the bottom wall of the groove 41 is provided with a second circular through hole 42 extending along the axial direction, and the axis of the second circular through hole 42 is collinear with the axis of the second bus-bar clamp 4; the second largest surfaces of the 4 electric conductors 1 are respectively attached to the 4 side walls of the groove 41; the outer peripheral surfaces of the first bus bar clamp 3 and the second bus bar clamp 4 are bonded with the inner peripheral surface of the insulator 2; each side wall of the groove 41 is provided with two mutually parallel watchband contact fingers 5; the watchband contact finger 5 abuts the second largest surface of the electrical conductor 1. Of course, in the case where the length of the electrical conductor 1 is excessively long, the number of the first bus bars 3 may be increased, and 4 electrical conductors 1 may be fixed to each other by a plurality of first bus bars 3 arranged at intervals.

Preferably: the electrical conductor 1 is made of copper. Of course, the electrical conductor 1 may also be made of other electrically conductive metals.

Example two

The embodiment of the application provides a closed type combined electrical appliance which comprises a metal cylinder and a busbar assembly; the busbar assembly is arranged in the metal cylinder, and the specific structure of the busbar assembly refers to the first embodiment, and because the closed type combined electrical appliance adopts all the technical schemes in the first embodiment, the busbar assembly at least has the beneficial effects brought by the technical scheme in the first embodiment, and is not described in detail herein.

Specific: the closed combined electrical apparatus also comprises a breaker, an isolating switch, a voltage transformer and a current transformer which are arranged in the metal cylinder; the circuit breaker, the isolating switch, the voltage transformer and the current transformer are connected with each other through the busbar assembly, and the specific connection mode between the circuit breaker, the isolating switch, the voltage transformer and the current transformer is connected according to common general knowledge, and the detailed description is omitted. It will be appreciated that the canister is also filled with insulating gas SF6.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims (10)

1. A busbar assembly, comprising:

4 conductors with the same shape, wherein the conductors are of a cuboid structure;

the length directions of the 4 electric conductors are parallel to each other;

the first maximum surfaces of the 4 electric conductors are respectively attached to 4 side surfaces of the prismatic space, and the bottom surface of the prismatic space is diamond-shaped;

the edge of the prismatic space is spaced from the first maximum surface;

the first maximum surfaces of two adjacent conductors are equally spaced from the adjacent edge;

4 pieces of the electric conductors are connected in parallel.

2. A busbar assembly according to claim 1, wherein:

the minimum interval between two adjacent conductors is d;

the thickness of the conductor is a;

d＞0.9a。

3. a busbar assembly according to claim 2, wherein:

an included angle formed by the first maximum surface and an equally divided section of the prismatic space is alpha, and the equally divided section is a plane where 2 non-adjacent edges of the prismatic space are located;

30°≤α≤50°。

4. a busbar assembly according to any one of claims 1 to 3, further comprising:

a cylindrical insulator;

4 pieces of the electric conductors are arranged in the insulator;

a space exists between the conductor and the inner peripheral surface of the insulator;

the insulator is coaxial with the prismatic space.

5. The busbar assembly of claim 4, further comprising:

a first bus-bar clamp and a second bus-bar clamp;

and 4 pieces of conductors are fixed in the insulator at one end in the length direction through the first bus bar clamp, and are fixed in the insulator at the other end through the second bus bar clamp.

6. A busbar assembly according to claim 5, wherein:

the first bus bar clamp is of a circular flat plate structure with the diameter equal to the inner diameter of the insulator;

the first bus-bar clamp is provided with 1 first round through hole and 4 square through holes which extend along the axial direction;

the axis of the first circular through hole is collinear with the axis of the first bus-bar clamp;

the conductor is matched with the square through hole in a penetrating way;

the second bus bar clamp is of a cylindrical structure with the diameter equal to the inner diameter of the insulator;

a groove extending along the axial direction is formed in the bottom surface of the second bus clamp, and the radial section of the groove is diamond-shaped;

the bottom wall of the groove is provided with a second circular through hole extending along the axial direction, and the axis of the second circular through hole is collinear with the axis of the second bus clamp;

the second largest surfaces of the 4 pieces of electric conductors are respectively attached to the 4 side walls of the groove;

the outer peripheral surfaces of the first bus bar clamp and the second bus bar clamp are attached to the inner peripheral surface of the insulator.

7. The busbar assembly of claim 6, further comprising;

watchband contact fingers arranged on the side walls of the grooves;

the watchband contact finger abuts the second maximum surface.

8. A busbar assembly according to any one of claims 1 to 3, wherein:

the electrical conductor is made of copper.

9. A closed type combined electrical apparatus, comprising:

a metal can and a busbar assembly as claimed in any one of claims 1 to 8;

the busbar assembly is arranged in the metal cylinder.

10. The sealed type combined electrical apparatus according to claim 9, further comprising:

the circuit breaker, the isolating switch, the voltage transformer and the current transformer are arranged in the metal cylinder;

the circuit breaker, the isolating switch, the voltage transformer and the current transformer are mutually connected through the busbar assembly.