Pouring bus unit and bus duct system for hydrogen energy environment

Abstract

The invention provides a pouring bus unit and a bus duct system used for a hydrogen energy environment, and relates to the technical field of power transmission equipment, the pouring bus unit used for the hydrogen energy environment comprises at least one busbar conductor and an insulation pouring bus duct integrally formed through a pouring technology, and the number of the busbar conductor is at least one; the busbar conductor is fixed on the inner side of the insulating pouring bus duct, and the insulating pouring bus duct is made of a polymer-based composite insulating material; the bus duct system comprises the pouring bus unit used for the hydrogen energy environment. The insulation pouring bus duct is formed by pouring the polymer-based composite insulation material, on one hand, the stability of the installation structure of the busbar conductor can be effectively guaranteed, the protection effect is improved, on the other hand, the insulation reliability and the anti-hydrogen environment adaptability are excellent, the use process is safe and reliable, meanwhile, the manufacturing process is simple, and the production cost is low. And the maintenance cost can be effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power transmission equipment, in particular to a cast busbar unit and busbar duct system for hydrogen energy environment. BACKGROUND

[0002] In the power transmission scene of hydrogen energy industry (such as hydrogen fuel cell power generation system, hydrogen energy storage power station, hydrogen pipeline supporting power facilities, etc.), as a key electrical energy distribution component, the busbar duct needs to meet the requirements of high insulation reliability, anti-hydrogen environment corrosion, compact structure and adaptation to dynamic current fluctuation. However, the busbar duct in the prior art is mostly designed based on traditional industrial power transmission scene, which is difficult to fully adapt to the special working conditions of hydrogen energy industry, and mainly has the following technical defects: 1. Insufficient insulation performance and hydrogen environment adaptability: The existing busbar duct mostly adopts air insulation, mica tape wrapping insulation or ordinary resin coating insulation structure. In the application environment of hydrogen energy industry, hydrogen molecules are small in volume and strong in permeability, which can easily penetrate into the gaps or micropores of traditional insulation structure, on the one hand, it may cause partial discharge in the insulation layer, accelerate the insulation aging; on the other hand, long-term contact of hydrogen with insulation materials may cause material chemical performance degradation (such as molecular chain rupture of part of resin insulation materials in hydrogen environment), which greatly shortens the service life of the busbar duct, and even causes insulation breakdown risk. 2. Weak structure stability and protection ability: The traditional busbar duct is mostly of assembled structure (such as connecting the duct body and cover plate by bolts), which has many joint gaps, not only easy to cause hydrogen, moisture or trace impurities (such as hydride dust) in hydrogen energy system to enter the inside of the duct body, pollute the surface of busbar conductor and affect the conductivity; at the same time, under the vibration working condition of hydrogen energy equipment (such as fuel cell stack operation vibration, jolt in transportation process), the connection is easy to loosen, which leads to the decrease of the overall structure stability of the busbar duct and increases the risk of abnormal increase of contact resistance. 3. Safety limitation: The traditional busbar duct mostly adopts assembled structure, and the busbar conductor is exposed to the external environment, which has high risk. In the flammable and explosive environment of hydrogen energy industry, once the conductor is exposed or the insulation is damaged, it is easy to cause safety accidents. In summary, the existing busbar duct cannot meet the stringent requirements of hydrogen energy industry on power transmission components in terms of insulation reliability, hydrogen corrosion resistance, structure stability and safety, and there is an urgent need for a busbar unit optimized for hydrogen scene. SUMMARY

[0003] The purpose of the present application is to provide a cast busbar unit and busbar duct system for hydrogen environment to solve the above technical problems in the prior art, and the preferred technical solutions in the present application can produce the following technical effects: see the detailed description below.

[0004] To achieve the above object, the present application provides the following technical solutions. The present application provides a cast busbar unit for hydrogen energy environment, comprising busbar conductors and an insulating cast busbar groove integrally formed by a casting process, wherein: the number of busbar conductors is at least one; the insulating cast busbar groove fixes the busbar conductors on the inner side thereof, and the insulating cast busbar groove is composed of a polymer-based composite insulating material.

[0005] Preferably, the polymer-based composite insulating material is a composite material of epoxy resin and inorganic mineral; the inorganic mineral includes quartz sand, calcium carbonate powder, and volcanic ash.

[0006] Preferably, the end portion of the busbar conductor is located on the outer side of the insulating cast busbar groove, and the cast busbar unit for hydrogen energy environment comprises an end portion isolation assembly arranged at the end portion of the busbar conductor for physically isolating the end portion of the busbar conductor.

[0007] Preferably, the end portion isolation assembly comprises two isolation end plates, wherein: the first side of the isolation end plate is provided with an isolation groove matched with the busbar conductor; the first sides of the two isolation end plates are oppositely arranged so that the two sides of the busbar conductor are respectively inserted into the corresponding isolation grooves.

[0008] The present application provides a busbar groove system comprising the cast busbar unit for hydrogen energy environment as described in any of the preceding embodiments.

[0009] Preferably, the busbar groove system comprises a busbar connector, and the number of the cast busbar units for hydrogen energy environment is multiple, and two adjacent cast busbar units for hydrogen energy environment are connected through the busbar connector.

[0010] Preferably, the busbar connector comprises a side plate, a partition plate, and a threaded connection assembly, wherein: the number of the side plates is two, and the two side plates are oppositely arranged; the number of the partition plates is at least one, and the partition plates are located between the two side plates; the side plates and the corresponding partition plates and the adjacent two partition plates form clamping grooves for clamping the end portions of the corresponding busbar conductors; and the threaded connection assembly penetrates through the side plates and the partition plates and can clamp the busbar conductors by the side plates and the partition plates.

[0011] Preferably, the two opposite edges of the side plate are inclinedly arranged away from the partition plate and form reinforcing edges.

[0012] Preferably, the busbar connector comprises a bowl-shaped sealing member, the number of the bowl-shaped sealing members is two, the threaded connection assembly penetrates through the bowl-shaped sealing members, and the bowl-shaped sealing members are located on the outer side of the side plate.

[0013] Preferably, the bus duct system comprises an end cover assembly and a connecting block assembly, wherein: the end cover assembly comprises end covers oppositely arranged on both sides of the bus connector, the end covers cover the end of the side plate, the end of the partition plate and all the clamping grooves, the inner side of the end cover is provided with a first insertion groove corresponding to the position of the end of the partition plate, and the two ends of the partition plate are respectively inserted into the corresponding two first insertion grooves; the connecting block assembly comprises a plurality of connecting blocks, the inner side of the end cover is provided with a second insertion groove corresponding to the position of the connecting block, and the two ends of the connecting block are respectively inserted into the corresponding two second insertion grooves, the cavity between the two connecting blocks forms an isolation cavity, and the bus bar conductor passes through the corresponding isolation cavity.

[0014] The pouring bus unit and the bus duct system for hydrogen energy environment provided by the application have at least the following beneficial effects: I. Significantly improve the insulation reliability and hydrogen environment adaptability: the insulation pouring bus duct adopts polymer-based composite insulation material and is integrally formed with the bus bar conductor through pouring process, which can form a seamless and high-density insulation structure. On the one hand, this structure can effectively block the penetration of hydrogen molecules, avoid the contact of hydrogen with the bus bar conductor or the entry of hydrogen into the insulation layer to cause partial discharge and insulation aging; on the other hand, the polymer-based composite insulation material itself has excellent chemical corrosion resistance and can resist trace amounts of hydride, moisture and other corrosive media that may exist in the hydrogen energy environment, greatly extending the service life of the bus unit in the hydrogen energy environment and reducing the risk of insulation breakdown.

[0015] II. Strengthen the structural stability and protection capability: the structure design of integral forming by pouring process discards the assembled structure of traditional bus duct, greatly reduces the joint gap, can effectively prevent impurities (such as hydride dust) and moisture in the hydrogen energy environment from entering the inside of the bus duct to pollute the bus bar conductor; at the same time, the integrated structure has higher overall rigidity, can withstand the vibration and impact during the operation of hydrogen energy equipment, effectively prevents the abnormal increase of contact resistance caused by structural looseness, and ensures the long-term stable operation of the bus unit. In addition, the dense insulation packaging structure also has the functions of dustproof and waterproof, further improving the environmental adaptability of the bus unit. III. Improve the scene adaptability and safety performance: in the actual application process, the number of bus bars and the corresponding insulation pouring bus ducts can be flexibly adjusted according to the power demand of different equipment in the hydrogen energy industry (such as single-phase power supply fuel cell module and multi-phase power supply hydrogen energy storage power station), which greatly improves the scene adaptability of the bus unit; at the same time, the insulation pouring bus duct fixes the bus bar conductor inside, which can avoid the exposure of the main part of the bus bar conductor, and combined with the excellent insulation performance of the polymer-based composite insulation material, can effectively reduce the risk of safety accidents (such as spark caused by conductor short circuit) in the flammable and explosive environment of the hydrogen energy industry, and ensure the safety of power transmission of the hydrogen energy system. Four, simplify production process and reduce maintenance cost: the design of the pouring process is integrally formed, compared with the traditional bus duct "slot processing + insulation layer wrapping / coating + assembly" multi-process, which can reduce the production link and improve the production efficiency; and the integrated insulation structure is not easy to be damaged locally, and the insulation layer does not need to be frequently repaired or replaced in the subsequent use process, thereby reducing the maintenance cost of the bus unit and meeting the demand of hydrogen energy industry for long-period stable operation of equipment. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, a brief introduction will be given below to the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0017] Figure 1 is a structural schematic diagram of the pouring bus unit of the present application; Figure 2 is an assembly schematic diagram of the end isolation assembly of the pouring bus unit of the present application; Figure 3 is a structural schematic diagram of the bus duct system of the present application; Figure 4 is an exploded schematic diagram of the bus duct system of the present application; Figure 5 is an assembly state schematic diagram of the bus connector, end cover assembly and connecting block assembly of the present application; Figure 6 is a structural schematic diagram of the bus connector of the present application from one perspective; Figure 7 is a structural schematic diagram of the bus connector of the present application from another perspective; Figure 8 is an exploded state schematic diagram of the bus connector, end cover assembly and connecting block assembly of the present application.

[0018] Reference signs 1, pouring bus unit; 11, bus bar conductor; 12, insulated pouring bus duct; 13, end isolation assembly; 131, isolation end plate; 132, isolation groove; 2, bus connector; 21, side plate; 211, reinforcing edge; 22, partition plate; 23, threaded connection assembly; 24, bowl-shaped sealing element; 3, end cover assembly; 31, end cover; 32, first plug-in groove; 33, second plug-in groove; 4, connecting block assembly; 41, connecting block; 42, plug-in end. DETAILED DESCRIPTION

[0019] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present application.

[0020] Embodiment 1 The present application provides a cast busbar unit 1 for hydrogen energy environment, referring to Figure 1 and Figure 2 , the cast busbar unit 1 for hydrogen energy environment includes busbar conductors 11 and insulating cast busbar slots 12, which are integrally formed by casting process.

[0021] The number of busbar conductors 11 is at least one; the insulating cast busbar slot 12 fixes the busbar conductor 11 on the inner side, and the insulating cast busbar slot 12 is composed of polymer-based composite insulating material.

[0022] The insulating cast busbar slot 12 formed by polymer-based composite insulating material can effectively ensure the stability of the installation structure of the busbar conductor 11, improve the protection effect, on the other hand, has superior insulation reliability and hydrogen environment adaptability, safe and reliable in use, at the same time, the manufacturing process is simple, which can effectively reduce the maintenance cost.

[0023] Embodiment 2 Embodiment 2 is based on embodiment 1: As shown in Figure 1 and Figure 2 , the polymer-based composite insulating material is a composite material of epoxy resin and inorganic mineral; the inorganic mineral includes quartz sand, calcium carbonate powder, volcanic ash, and quartz sand grade S1, S2, S3 and S4 can be selected.

[0024] When casting, the epoxy resin, the inorganic mineral and the curing agent are prepared according to the proportion of casting.

[0025] In the foregoing components, the granular structure of quartz sand and calcium carbonate powder can fill the micropores in the epoxy resin matrix, the active ingredients of volcanic ash can react with epoxy resin to form a more dense three-dimensional network structure, further reducing the porosity of the insulating material, thereby effectively blocking the hydrogen molecule penetration, avoiding the problem of partial discharge caused by hydrogen accumulation in the insulating layer, prolonging the service life of the insulating layer in the hydrogen energy environment.

[0026] And the high strength characteristics of inorganic minerals (especially quartz sand) can improve the tensile strength and bending strength of the composite insulating material, can withstand the vibration impact during the operation of the hydrogen energy equipment, and avoid the cracking of the insulating cast bus duct due to stress; at the same time, the inorganic minerals have excellent chemical stability, can inhibit the molecular chain rupture of the epoxy resin in the hydrogen energy environment (containing trace hydride and water vapor), reduce the aging shrinkage of the insulating material, and ensure the long-term stability of the insulating performance.

[0027] At the same time, quartz sand, calcium carbonate powder and volcanic ash are low-cost inorganic fillers, which can reduce the raw material cost of the polymer-based composite insulating material under the premise of ensuring the insulating performance; and the compatibility of such inorganic minerals and epoxy resin is good, and the fluidity and molding effect of the casting process will not be affected.

[0028] As an optional implementation, the end portion of the busbar conductor 11 is located outside the insulating cast bus duct 12, and the cast bus unit 1 comprises an end portion isolation assembly 13 arranged at the end portion of the busbar conductor 11 for physically isolating the end portion of the busbar conductor 11.

[0029] Since the end portion of the busbar conductor 11 is the key part connected with the external equipment, if it is impacted or vibrated, the end portion may be deformed or the connection interface may be damaged; the arrangement of the end portion isolation assembly 13 can effectively ensure the stability of the end portion on the basis of effectively isolating the end portions of adjacent busbar conductors 11, avoid damage to the end portion structure, and ensure long-term reliable connection of the bus unit.

[0030] As an optional implementation, the end portion isolation assembly 13 comprises two isolation end plates 131, and the first side of the isolation end plate 131 is provided with an isolation groove 132 matched with the busbar conductor 11; the first sides of the two isolation end plates 131 are oppositely arranged, and the two sides of the busbar conductor 11 are respectively inserted into the corresponding two isolation grooves 132.

[0031] The isolation groove of the isolation end plate 131 is matched with the busbar conductor 11, and the busbar end portion can be accurately positioned by the "two-side insertion" mode to avoid deviation of the busbar end portion during installation or vibration; at the same time, the two isolation end plates 131 are oppositely arranged to form a clamping force from both sides of the busbar conductor 11, so as to ensure the stability of the end portion isolation assembly 13 and the busbar conductor 11, and the end portion isolation assembly 13 will not fall off due to vibration.

[0032] Example 3 Example 3 is based on example 2: The present application provides a bus duct system, as shown in Figures 1 to 8 The bus duct system comprises a bus connector 2, and the number of cast bus units 1 is multiple, and two adjacent cast bus units 1 are connected through the bus connector 2.

[0033] In practical application, according to the power demand of hydrogen energy equipment, a cast busbar unit 1 with a corresponding phase number structure can be selected, such as single-phase, three-phase or multi-phase power supply.

[0034] As an optional embodiment, the busbar connector 2 comprises side plates 21, partition plates 22 and threaded connection assemblies 23.

[0035] The number of side plates 21 is two, and the two side plates 21 are oppositely arranged; the number of partition plates 22 is at least one, and all the partition plates 22 are arranged between the two side plates 21 and are spaced apart; the side plate 21, the corresponding partition plate 22 and the two adjacent partition plates 22 form a clamping groove for clamping the end of the corresponding busbar conductor 11.

[0036] The threaded connection assembly 23 comprises a connecting bolt and a connecting nut, the end of the connecting bolt passes through the side plate 21 and the partition plate 22, and is threadedly connected with the connecting nut, so as to clamp the busbar conductor 11 by the side plate 21 and the partition plate 22.

[0037] The side plate 21, the partition plate 22 and the threaded connection assembly 23 cooperate with each other to form a uniform clamping force for the busbar conductor 11, so as to avoid poor contact caused by uneven clamping; at the same time, the partition plate 22 can separate different busbar conductors 11 (such as multi-phase busbar), so as to prevent short circuit between the busbars and ensure independent and stable transmission of power of each phase.

[0038] As an optional embodiment, the two opposite edges of the side plate 21 are inclinedly arranged away from the partition plate 22 and form reinforcing edges 211.

[0039] When the busbar connector 2 clamps the busbar conductor 11, the side plate 21 needs to bear the tightening force of the threaded connection assembly 23, and is easy to bend and deform; the reinforcing edge with the bending structure can increase the sectional moment of inertia of the edge of the side plate 21, so as to significantly improve the bending resistance of the side plate 21 and avoid insufficient clamping force caused by deformation of the side plate 21 during clamping.

[0040] As an optional embodiment, the busbar connector 2 comprises bowl-shaped sealing members 24, the number of the bowl-shaped sealing members 24 is two, the connecting bolt passes through the bowl-shaped sealing members 24, and the bowl-shaped sealing members 24 are located outside the side plate 21.

[0041] The bowl-shaped sealing members 24 are used for sealing the gap between the threaded connection assembly 23 and the side plate 21, the sealing effect is obvious, the adaptability to hydrogen environment is further improved, the elastic pressure of the bowl-shaped sealing members 24 forms a certain pre-tightening force compensation for the threaded connection assembly 23, vibration-induced loosening of threads is avoided, and long-term stable clamping force is ensured.

[0042] As an optional embodiment, the busbar slot system comprises an end cover assembly 3 and a connecting block assembly 4.

[0043] The end cover assembly 3 comprises end covers 31 arranged oppositely on both sides of the busbar connector 2, which cover the ends of the side plates 21, the ends of the partition plates 22 and all the clamping grooves. The inner side of the end cover 31 is provided with a first insertion groove 32 corresponding to the position of the end of the partition plate 22, and the end of the partition plate 22 is inserted into the corresponding two first insertion grooves 32.

[0044] The connecting block assembly 4 comprises a plurality of connecting blocks 41, and the inner side of the end cover 31 is provided with a second insertion groove 33 corresponding to the position of the connecting block 41. The end of the connecting block 41 is provided with an insertion end 42, and the size of the insertion end 42 gradually decreases away from the body part of the connecting block 41. The two insertion ends 42 of the connecting block 41 are inserted into the corresponding two second insertion grooves 33, and the cavity between the two connecting blocks 41 forms an isolation cavity, and the busbar conductor 11 passes through the corresponding isolation cavity.

[0045] In this way, on the one hand, the busbar connector 2 can be fully enclosed and protected: the end cover 31 covers the edges of the side plates 21 and the partition plates 22 and all the clamping grooves, which can block the openings from both sides of the connector to prevent hydrogen, moisture and dust from entering the inside of the connector. At the same time, the connecting blocks 41 are fixed by the insertion grooves to form a continuous isolation structure, which completely isolates the internal space of the connector from the external environment, further improving the overall sealing of the busbar system. On the other hand, the isolation cavities between the connecting blocks 41 correspond one-to-one to the busbar conductors 11, which can separate different busbar conductors 11 in independent cavities to avoid short circuits between multiple busbar conductors 11 due to vibration, displacement or insulation damage.

[0046] In the description of the present application, it should be understood that the terms "upper", "lower", "inner", "outer", "top", "bottom" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0047] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple", "several" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0048] In this application, unless otherwise clearly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be directly connected, or indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise clearly limited. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0049] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A cast busbar unit for a hydrogen energy environment, characterized by, The application relates to a busbar slot system for a hydrogen energy environment, which comprises busbar conductors and an insulating cast busbar slot integrally formed through a casting process, wherein: the number of the busbar conductors is at least one; the insulating cast busbar slot fixes the busbar conductors on the inner side of the insulating cast busbar slot, and the insulating cast busbar slot is made of a polymer-based composite insulating material. The number of the busbar conductors is at least one. The insulating cast busbar slot fixes the busbar conductors on the inner side of the insulating cast busbar slot, and the insulating cast busbar slot is made of a polymer-based composite insulating material.

2. The cast busbar unit for a hydrogen energy environment according to claim 1, characterized by, The polymer-based composite insulating material is a composite material of epoxy resin and inorganic minerals. The inorganic minerals include quartz sand, calcium carbonate powder and volcanic ash.

3. The cast busbar unit for a hydrogen energy environment according to claim 1, characterized by, The end portions of the busbar conductors are located on the outer side of the insulating cast busbar slot, and the cast busbar unit for the hydrogen energy environment comprises an end portion isolation assembly arranged at the end portions of the busbar conductors and used for physically isolating the end portions of the busbar conductors.

4. The cast busbar unit for a hydrogen energy environment according to claim 3, characterized by, The end portion isolation assembly comprises two isolation end plates, wherein: A first side of the isolation end plate is provided with an isolation groove matched with the busbar conductor; The first sides of the two isolation end plates are oppositely arranged so that the two sides of the busbar conductor are respectively inserted into the corresponding isolation grooves.

5. A busway system characterized by, The application relates to a busbar slot system for a hydrogen energy environment.

6. The busway system of claim 5, wherein, The busbar slot system comprises busbar connectors, and the number of the cast busbar units for the hydrogen energy environment is multiple, and two adjacent cast busbar units for the hydrogen energy environment are connected through the busbar connectors.

7. The busway system of claim 6, wherein, The busbar connector comprises side plates, isolation plates and a threaded connection assembly, wherein: The number of the side plates is two, and the two side plates are oppositely arranged; The number of the isolation plates is at least one, and the isolation plates are located between the two side plates; The side plates, the corresponding isolation plates and the adjacent two isolation plates form clamping grooves used for clamping the end portions of the corresponding busbar conductors; The threaded connection assembly penetrates through the side plates and the isolation plates, and can clamp the busbar conductors by the side plates and the isolation plates.

8. The busway system of claim 7, wherein, The two opposite edges of the side plates are obliquely arranged away from the isolation plates, and form reinforcing edges.

9. The busway system of claim 7, wherein, The busbar connector comprises bowl-shaped sealing members, the number of the bowl-shaped sealing members is two, the threaded connection assembly penetrates through the bowl-shaped sealing members, and the bowl-shaped sealing members are located on the outer side of the side plates.

10. The busway system of claim 7, wherein, The busbar slot system comprises end cap assemblies and connecting block assemblies, wherein: The end cap assembly comprises end portion covers oppositely arranged on the two sides of the busbar connector, the end portion covers cover the end portions of the side plates, the end portions of the isolation plates and all the clamping grooves, the inner side of the end portion cover is provided with first plug-in grooves at positions corresponding to the end portions of the isolation plates, and the two ends of the isolation plates are respectively inserted into the corresponding two first plug-in grooves; The connecting block assembly comprises multiple connecting blocks, the inner side of the end portion cover is provided with second plug-in grooves at positions corresponding to the connecting blocks, the two ends of the connecting blocks are respectively inserted into the corresponding two second plug-in grooves, a cavity between the two connecting blocks forms an isolation cavity, and the busbar conductor penetrates through the corresponding isolation cavity.

Images