Low-voltage power distribution cabinet capable of improving temperature rise of switch end

Abstract

A low-voltage power distribution cabinet capable of improving temperature rise of a switch end comprises a cabinet body, a circuit breaker is arranged in the cabinet body, the circuit breaker is connected with six first copper bars, the first copper bars are horizontally placed, the number of the first copper bars is six, the first copper bars are arranged in an overlapped mode, the first copper bars are further connected with second copper bars, and the second copper bars are vertically arranged. According to the utility model, the traditional copper bar connection mode is changed, the direction of the terminal stud of the circuit breaker is changed, the connection copper bars of the circuit breaker are designed according to the maximum current-carrying capacity, the connection between the copper bars is also designed to be a novel connection mode, the current-carrying capacity of the connection copper bars is improved, and the current-carrying capacity of the current-carrying capacity of the current-carrying capacity of the current-carrying capacity of the current-carrying capacity of the current-carrying capacity of the current-carrying capacity of the circuit breaker is improved. The heat dissipation area of the copper bar is increased, the copper bar with the same weight can be adopted, and the current-carrying capacity of the copper bar can be improved through the design; the temperature rise of the switch end and the connecting copper bar can be improved without adding a fan to the power distribution cabinet, so that the temperature rise of the low-voltage switch cabinet meets the national standard requirement: the temperature rise at the lap joint of the wiring end of the circuit breaker and the copper bar is not more than 70K.

Description

Technical Field

[0001] The utility model relates to the field of power distribution cabinets, in particular to a low-voltage power distribution cabinet capable of improving the temperature rise of switch ends. Background Art

[0002] At present, the electricity consumption of each household increases with the improvement of modern living standards, which leads to the increasing capacity of a single low-voltage distribution cabinet, which will inevitably lead to an increase in the rated current on the switch. Because the space in the low-voltage cabinet is limited, the increase in current directly leads to an increase in heat generation in the distribution cabinet. The high temperature of electrical and insulating components in the switch cabinet will shorten their service life. If the temperature rise in the cabinet is not controlled in the hot summer, the temperature of the main switch in the cabinet will rise, which may cause the switch to trip and cause power outages. In severe cases, it may directly burn components and cause fires, bringing immeasurable casualties and property losses to the national economy.

[0003] At present, there are many measures to reduce the temperature of high-current distribution cabinets, such as incoming line cabinets, such as the use of exhaust technology: adding ventilation and exhaust holes to the cabinet, or increasing the cross-section of internal connecting wires and copper bars, etc., which can improve the temperature rise in the cabinet. However, these methods have a relatively low cooling efficiency for the cabinet, and are not economical and environmentally friendly. For example, the use of exhaust fans consumes a certain amount of electrical energy. The use of a large number of fans will incur huge expenses every year after accumulation. In addition, fans also have a service life, so the effect of use is not optimal. Once the service life ends, the safe operation of the low-voltage cabinet cannot be guaranteed.

[0004] The copper busbar connection method used for switches in the existing low-voltage distribution board with high current is horizontally connected, and there is no more economical cooling measure such as adding heat sink, but only adding ventilation holes and exhaust fans on the rear door panel of the low-voltage cabinet. The cooling efficiency of this method is relatively low, because the traditional temperature controller usually collects the ambient temperature inside the cabinet, which is not very accurate, and cannot collect the temperature of the heat source, quickly start the fan, and blow the cold air directly to the heat source, which is very wasteful of electricity. Once the life of the fan or temperature controller ends, the safe operation of the low-voltage cabinet cannot be guaranteed. Utility Model Content

[0005] In order to solve the above problems, the present technical solution provides a low-voltage distribution cabinet which improves the temperature rise of the switch ends.

[0006] To achieve the above purpose, the technical solution is as follows:

[0007] A low-voltage power distribution cabinet for improving the temperature rise of switch ends comprises a cabinet body, a circuit breaker is arranged in the cabinet body, the circuit breaker is connected to a first copper bar, the first copper bar is horizontally placed, the number of the first copper bars is six and they are arranged overlappingly, the first copper bar is also connected to a second copper bar, the second copper bar is vertically arranged, the number of the second copper bars is two and they are arranged overlappingly, and the second copper bar is used to transmit electrical energy to a load.

[0008] In some embodiments, the size of the first copper bar is 100*5MM, and the size of the second copper bar is 100*10MM.

[0009] In some embodiments, it also includes a first special-shaped heat sink disposed on one side of the first copper bar, and a second special-shaped heat sink disposed on one side of the second copper bar.

[0010] In some embodiments, the first special-shaped heat sink and the second special-shaped heat sink are wavy in cross-section.

[0011] In some embodiments, a mounting plate is provided between two of the second copper bars, and the mounting plate is connected to the first copper bar by screws.

[0012] The beneficial effects of this application are:

[0013] The present application changes the traditional copper busbar connection method, changes the direction of the wiring terminal of the circuit breaker, and designs the copper busbar connected to the circuit breaker in a manner that maximizes its current carrying capacity. The connection between the copper busbars is also designed as a new connection method to increase the heat dissipation area of ​​the copper busbar, so that the copper busbar of the same weight can be used. Through the above design, the current carrying capacity of the copper busbar can be increased; the distribution cabinet does not need to add a fan, which can improve the temperature rise of the switch terminal and the connecting copper busbar, so that the temperature rise of the low-voltage switch cabinet meets the national standard requirements: the temperature rise of the wiring terminal of the circuit breaker and the copper busbar overlap is not more than 70K. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the drawings required for describing the embodiments are briefly introduced below.

[0015] Figure 1 This is a schematic diagram of the structure of the embodiment of the utility model Figure 1 ;

[0016] Figure 2 This is a schematic diagram of the structure of the embodiment of the utility model Figure 2 ;

[0017] Figure 3 It is a schematic diagram of the structure of the first special-shaped heat sink of an embodiment of the utility model. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects solved by the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0019] Please refer to Figure 1-3 As shown, a low-voltage power distribution cabinet for improving the temperature rise of switch ends includes a cabinet body 1, a circuit breaker 2 is arranged in the cabinet body 1, the circuit breaker 2 is connected to a first copper bar 3, the first copper bar 3 is horizontally placed, the number of the first copper bars 3 is six and they are overlapped, the first copper bar 3 is also connected to a second copper bar 4, the second copper bars 4 are vertically arranged, the number of the second copper bars 4 is two and they are overlapped, the second copper bar 4 is used to transmit electric energy to the load, the upper pile of the incoming circuit breaker 1QF is connected to the vertical copper bar (L11, L12, L13, N), and extends upward to the busbar room on the top of the cabinet, and is connected to the horizontal busbar of the feeder cabinet behind the cabinet (I-section busbar) to provide power for each feeder circuit behind the I-section busbar.

[0020] In this embodiment, the size of the first copper busbar 3 is 100*5MM, and the size of the second copper busbar 4 is 125*10MM.

[0021] In this embodiment, it further includes a first special-shaped heat sink 5 provided on one side of the first copper bar 3 and a second special-shaped heat sink 6 provided on one side of the second copper bar 4 .

[0022] In this embodiment, the cross-sections of the first special-shaped heat sink 5 and the second special-shaped heat sink 6 are wavy.

[0023] In this embodiment, a mounting plate 7 is provided between two of the second copper bars 4 , and the mounting plate 7 is connected to the first copper bar 3 by screws.

[0024] A new copper busbar connection measure can improve the temperature rise of the switch end. The composition of the low-voltage distribution cabinet is generally divided into the following two or three parts: structural parts, primary copper busbar connectors, and electrical parts; the main purpose of this design is to improve the temperature rise of the switch end and the copper busbar connected to the end; so the copper busbar design in the cabinet is mainly introduced in detail as follows.

[0025] In terms of structural parts, galvanized steel plates are bent into columns and beams with standard mold holes, which are assembled into the skeleton of the low-voltage cabinet, and then the top plate + front and rear panels + switch cover plates + partitions + busbar clamps + mounting brackets + insulating beams are assembled into a standard low-voltage distribution cabinet with a width of 800*depth of 1000*height of 2000mm. The cabinet is divided from top to bottom into the busbar room on the top of the cabinet, the frame circuit breaker room in front of the cabinet, and the vertical busbar connection room for the frame circuit breaker busbar connection behind the cabinet. Insulating beams or busbar clamps are set on both sides and horizontally of the busbar channel, and the above-mentioned structural parts are assembled into a closed metal low-voltage distribution switch cabinet.

[0026] The design instructions are given according to the rated current of the switches currently used in the market, with the maximum being 4000A for the switch incoming cabinet, and the switches with other rated currents are similar.

[0027] First, a 4000A frame circuit breaker 1QF is fixedly installed in the above-mentioned frame circuit breaker room; the upper and lower ends of the circuit breaker are rotated 90 degrees from the traditional horizontal direction to vertical wiring; because of the convection heat dissipation of air, the heat dissipation of the horizontal plane and the vertical plane is very different, and the current carrying capacity of the vertical installation is larger than that of the horizontal installation, and is about 10% higher. The upper pile of 1QF (Note: the main copper busbar wiring terminal of the circuit breaker) is connected horizontally with three 100*10 bars and horizontal terminals according to the traditional method; by consulting the corresponding standards and power supply and distribution design manual, the current carrying capacity of the copper busbar placed horizontally is about 3600A; if the above-mentioned horizontal connection is changed to a vertical connection, its current carrying capacity can reach about 3950A; but it still fails to reach 4000A;

[0028] Second, because the copper busbar with the same cross-section, if it is changed from one to two, the current carrying capacity of the copper busbar will increase by about 10% due to the increase in the heat dissipation surface; therefore, the three rows of 100*10 are changed to six rows of 100*5 and overlapped with the terminal incoming line of the circuit breaker; after overlapping, it needs to be connected with the two 125*10 vertical copper busbars from the top of the cabinet; this connection method is to fold the six 100*5 bars into an L shape, with three bars on each side and one face on each side, with a total of two faces overlapped with the vertical bars; because this overlap surface is smaller and narrower than the traditional overlap surface, it requires a very good copper busbar processing technology to reduce processing errors and accumulated errors. Finally, the copper busbar connected to the end and the vertical busbar are well overlapped to meet the connection resistance and current carrying capacity;

[0029] Third, through a large number of temperature rise tests, it is proved that the heat generation in the whole cabinet is more serious mainly at the connection between the frame circuit breaker end and the copper bar. In order to achieve better heat dissipation effect, a special-shaped heat sink is added to the overlap of the circuit breaker end and the copper bar. This heat sink is made of 2mm thin copper plate with good thermal conductivity. It is stamped into a wavy heat sink to increase the heat dissipation surface and fixed to the circuit breaker end and the copper bar with copper bar overlap bolts. Considering that the copper heat sink is a conductive metal, all installations at the end need to avoid phase-to-phase and phase-to-ground short circuits, and safety regulations and live distances must be ensured.

[0030] A 4-pole frame circuit breaker has 8 terminals, all of which adopt the above-mentioned copper busbar overlapping method. After the above-mentioned design processing and modification, conductive paste is finally applied to the overlapping surface of each copper busbar. This conductive paste can reduce the resistance of the copper busbar connection and increase the conductivity and heat dissipation efficiency.

[0031] The technical effect of this scheme is

[0032] First, compared with the traditional copper busbar connection method of the low-voltage distribution cabinet, this solution does not increase the cross-sectional area of ​​the copper busbar, does not require additional fans, and only changes the connection method between the copper busbar and the circuit breaker and the placement of the copper busbar. The cross-sectional area remains unchanged while only the number of copper busbars is increased. This makes the temperature rise of the key heating parts in the low-voltage cabinet meet the national standard requirements, that is, the temperature rise of the wiring terminal of the circuit breaker and the copper busbar overlap is no more than 70K.

[0033] Secondly, compared with the traditional low-voltage feeder cabinet, the circuit breaker terminals of this solution are wired vertically, and heat sinks are added to the circuit breaker terminals and the joints between the terminals and the copper bar; and conductive paste is applied to the connection surface to dissipate heat and conduct electricity; the heat dissipation of the connection position inside the cabinet is fully increased to prevent the cabinet from heating up and affecting the electrical life and safe operation of the equipment;

[0034] The superposition of the above two solutions enables the use of copper bars of the same cross-section in the distribution cabinet, which increases the current carrying capacity by at least 20%. Compared with the traditional solution of using fans for heat dissipation, this solution is easy to process, simple to install, and cost-saving. It can meet the full current operation of the cabinet while ensuring the long-term safe operation of the low-voltage cabinet.

[0035] The above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application. Other principles and basic structures that are the same or similar to those of the present application are within the protection scope of the present application.

Claims

1. A low-voltage distribution cabinet for improving the temperature rise of switch ends, characterized in that: The invention comprises a cabinet (1), wherein a circuit breaker (2) is arranged in the cabinet (1), wherein the circuit breaker (2) is connected to a first copper bar (3), wherein the first copper bar (3) is horizontally arranged, the number of the first copper bars (3) is six and they are arranged in an overlapping manner, and the first copper bar (3) is also connected to a second copper bar (4), wherein the second copper bars (4) are vertically arranged, the number of the second copper bars (4) is two and they are arranged in an overlapping manner, and the second copper bars (4) are used to transmit electric energy to a load.

2. A low-voltage power distribution cabinet for improving the temperature rise of switch ends according to claim 1, characterized in that: The size of the first copper busbar (3) is 100*5MM, and the size of the second copper busbar (4) is 125*10MM.

3. A low-voltage power distribution cabinet for improving the temperature rise of switch ends according to claim 2, characterized in that: It also includes a first special-shaped heat sink (5) provided on one side of the first copper bar (3), and a second special-shaped heat sink (6) provided on one side of the second copper bar (4).

4. A low-voltage power distribution cabinet for improving the temperature rise of switch ends according to claim 3, characterized in that: The first special-shaped heat sink (5) and the second special-shaped heat sink (6) have wave-shaped cross sections.

5. A low-voltage power distribution cabinet for improving the temperature rise of switch ends according to claim 1, characterized in that: A mounting plate (7) is provided between the two second copper bars (4), and the mounting plate (7) is connected to the first copper bar (3) via screws.

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