Medium voltage electrical equipment cabinet
By using a longitudinal metal reinforcing rod and insulating tube structure with column connection in medium-voltage electrical equipment boxes, the problems of insufficient mechanical strength and electrical insulation performance are solved, achieving effective insulation and low-cost improvement in high-pressure gas environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SCHNEIDER ELECTRIC IND SAS
- Filing Date
- 2021-11-23
- Publication Date
- 2026-08-04
AI Technical Summary
Existing medium-voltage electrical equipment boxes face problems of insufficient mechanical strength and poor electrical insulation performance when using non-fluorinated gases, and traditional solutions are costly or difficult to achieve effective insulation.
The enclosure features a column structure, with the columns connected by longitudinal metal reinforcing rods. The reinforcing rods are then surrounded by insulating tubing to ensure insulation performance. Spacers and shunts are used to further enhance electrical insulation and reduce the risk of electric arcing.
It provides mechanical strength suitable for high-pressure gases, ensures electrical insulation performance, and reduces additional costs. It is suitable for non-fluorinated gases such as air or nitrogen, and reduces the impact on the manufacturing process.
Smart Images
Figure CN114667007B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of enclosures intended to contain medium-voltage distribution units, that is, voltages between 1 and 52 kV. These enclosures may contain, for example, arc-extinguishing devices such as switches, circuit breakers, or disconnectors, which ensure the operation of the medium-voltage distribution network. Background Technology
[0002] Enclosures containing medium-voltage electrical equipment must ensure electrical insulation between the equipment and between the equipment and the outside world to prevent arcing and discharge; this is also known as "cable-stayed enclosure".
[0003] For this reason, pressurized fluorinated gases, such as sulfur hexafluoride (which has satisfactory dielectric properties), are typically used to fill the chamber. However, this gas also has a high global warming potential. Therefore, gases with low warming potential, such as air, nitrogen, or carbon dioxide, can be used instead. These gases have lower dielectric strength than the gases being replaced. To maintain the same electrical insulation performance, the chamber pressure must be more than twice as high.
[0004] The mechanical stress transmitted to the box structure by the pressure applied to the box panels increases under the influence of increased gas pressure inside the box. To prevent this structural deformation, reinforcement is necessary. One possibility is to increase the thickness of the panels and / or structure. The disadvantage of this solution is a significant increase in the cost of the box.
[0005] Another possibility is to have a robust frame structure made of columns, with metal reinforcements added to connect the columns together. In this case, it is difficult to ensure the insulation of these reinforcements, and it is also difficult to prevent arcing between the reinforcements and the electrical units inside the enclosure.
[0006] It is well known that electrical insulators made of plastic materials such as elastomers are used to electrically insulate these metal reinforcements from the live components in the enclosure, but this solution is expensive. It is also known to electrically insulate these metal reinforcements by overmolding them with thermosetting resins. However, expansion can lead to fatigue of the insulating material, thus introducing the risk of interface degradation with the metal reinforcement.
[0007] Therefore, there is a need for a box that has improved mechanical strength based on metal reinforcing bars, and has lower additional cost and improved electrical insulation performance than known solutions in the prior art. Summary of the Invention
[0008] Therefore, the present invention proposes a enclosure for a medium-voltage electrical unit, the enclosure being designed to contain gas at a pressure greater than atmospheric pressure, the enclosure having:
[0009] -A structure with columns
[0010] - A panel fixed to the column, the panel is configured to receive the pressure of the pressurized gas.
[0011] - At least one metal reinforcing rod extending in the longitudinal direction, which connects the two columns together to resist deformation of the columns under gas pressure.
[0012] -At least one first electrically insulating tube,
[0013] At least one longitudinal portion of the reinforcing rod is surrounded by a first insulating tube.
[0014] The reinforcing rod strengthens the structure and prevents deformation under the pressure of pressurized gas applied to the panel. By surrounding the metal reinforcing rod with insulating tubing, its insulation is improved, and the risk of arcing between the reinforcing rod and the electrical units housed within the enclosure is eliminated. Therefore, the proposed solution provides mechanical strength compatible with the pressures employed within the enclosure while ensuring satisfactory electrical insulation. The additional costs involved are minimal, and the impact on the enclosure's manufacturing process is negligible.
[0015] The features listed in the following paragraphs can be implemented independently of each other, or in any technically possible combination:
[0016] The container is intended to hold either a pure gas or a gas mixture. In particular, the gas that the container is intended to hold may be a binary mixture.
[0017] The reinforcing rod and the first insulating tube are coaxial.
[0018] The first insulating tube is installed longitudinally between the two columns.
[0019] The inner surface of the first insulating tube is away from the side surface of the reinforcing rod.
[0020] The inner surface of the first insulating tube is separated from the side surface of the reinforcing rod by pressurized gas.
[0021] The reinforcing rod and the first insulating tube are configured such that the pressure of the gas inside the insulating tube is equal to the pressure of the gas outside the insulating tube.
[0022] Therefore, the insulating tube will not be subjected to any force that would deform it.
[0023] The first insulating tube is filled with insulating foam.
[0024] The reinforcing bar is straight.
[0025] The reinforcing rod is cylindrical.
[0026] The diameter of the reinforcing rod is between 6 and 20 millimeters.
[0027] According to a variation of one implementation, the reinforcing rod is a threaded rod.
[0028] Therefore, reinforcing bars are readily available and easier to secure.
[0029] The first insulating tube is cylindrical.
[0030] The first insulating tube is made of polypropylene or any other electrically insulating thermosetting, thermoplastic, or ceramic material.
[0031] This material has excellent electrical insulation properties.
[0032] The outer diameter of the first insulating tube is between 10 and 24 millimeters.
[0033] The thickness of the first insulating tube is between 1 and 6 millimeters.
[0034] The length of the first insulating tube is greater than 80% of the total length of the reinforcing rod.
[0035] According to one embodiment, the ratio between the diameter of the reinforcing rod and the outer diameter of the first insulating tube is between 0.1 and 0.6.
[0036] According to one embodiment, the box includes a second insulating tube, and the second insulating tube surrounds the first insulating tube.
[0037] The second insulating tube is coaxial with the first insulating tube.
[0038] The outer diameter of the second insulating tube is between 14 and 40 mm.
[0039] The inner surface of the second insulating tube is far from the outer surface of the first insulating tube.
[0040] The inner surface of the second insulating tube is separated from the outer surface of the first insulating tube by a layer of pressurized gas.
[0041] The box has spacers that are configured to hold the insulating tube and the reinforcing rod in place coaxially.
[0042] According to one embodiment variation, the box has a spacer configured to hold a first insulating tube and a reinforcing rod in place coaxially, and to hold a second insulating tube and a reinforcing rod in place coaxially.
[0043] The spacer has a through slot to accommodate the reinforcing rod.
[0044] The spacer has a receiving area that is at least partially integrated into the first insulating tube.
[0045] The spacer is disposed at the axial end of the first insulating tube.
[0046] The spacer is disposed at the axial end of the second insulating tube.
[0047] The spacer is in the form of a stepped cylindrical ring.
[0048] One axial end of the first insulating tube contacts the step of the spacer.
[0049] The inner surface of the stepped ring contacts the reinforcing rod, and the outer surface of the ring contacts the inner surface of the insulating tube.
[0050] The spacer has a circular groove in which one axial end of the first insulating tube is accommodated.
[0051] The first spacer and the second spacer are respectively disposed at one axial end of the first insulating tube.
[0052] The spacers are made of polypropylene or any other electrically insulating thermosetting, thermoplastic, or ceramic material. Depending on the dielectric conditions of the enclosure, the spacers may optionally be made of metal.
[0053] The spacer is configured to allow pressurized gas to pass between the outside and inside of the first insulating tube.
[0054] The reinforcing bar extends laterally relative to the column.
[0055] The reinforcing rod is perpendicular to the column.
[0056] The box includes at least two opposing planes, and reinforcing rods extend between the uprights fixed to the two opposing planes of the box.
[0057] The reinforcing rod is connected and fixed to the uprights of the larger panel of the box.
[0058] The enclosure includes two parallel uprights defining a plane perpendicular to at least one panel, and includes two mutually parallel reinforcing rods extending perpendicularly relative to the two uprights. Therefore, it can be understood that the enclosure includes at least two parallel uprights. Depending on the number and type of electrical equipment housed within the enclosure, it may include a greater number of uprights.
[0059] According to one embodiment, the first insulating tube is surrounded by a disc-shaped shunt.
[0060] According to another embodiment, one axial end of the first insulating tube contacts the disc-shaped shunt.
[0061] According to an exemplary embodiment of the present invention, each axial end of the first insulating tube is in contact with a disc-shaped shunt.
[0062] The shunt is electrically insulated.
[0063] The shunt is made of polypropylene or any other electrically insulating thermosetting, thermoplastic, or ceramic material.
[0064] The shunt and the first insulating tube are coaxial.
[0065] The shunt extends radially in a plane inclined relative to the longitudinal axis of the first insulating tube. The shunt may also extend in a plane perpendicular to the longitudinal axis of the first insulating tube.
[0066] The contact area between the first insulating tube and the shunt extends continuously in 360°.
[0067] The outer diameter of the splitter is between 15 and 150 mm.
[0068] According to one embodiment, the spacer and the shunt form a single-piece assembly.
[0069] The first insulating tube is surrounded by a shunt at each end.
[0070] The distributor is located near the column.
[0071] The distance between the distributor and the column is between 1 and 30 millimeters.
[0072] According to one embodiment, the second insulating tube is surrounded by a disc-shaped shunt.
[0073] One axial end of the second insulating tube contacts the disc-shaped shunt.
[0074] The reinforcing rod is connected to the structural column by a nut.
[0075] According to one embodiment, the connection between the reinforcing rod and the column of the structure has a lock nut, and the column is pressed between the nut and the lock nut.
[0076] The reinforcing rod is fixed to the column by rivets.
[0077] The reinforcing rod is fixed to the column by a flexible locking connection element.
[0078] The columns are made of metal profiles.
[0079] The columns are U-shaped profiles.
[0080] The nuts connecting the uprights and the reinforcing rods are housed between the legs of the U.
[0081] The nuts connecting the column and the reinforcing rod rest against the base of the U.
[0082] According to one embodiment of the box, a first pair of opposing columns are connected by at least two reinforcing rods, and a second pair of opposing columns are connected by at least two reinforcing rods.
[0083] At least two reinforcing bars are parallel.
[0084] The container has three separate compartments, and the reinforcing rods of the first pair of uprights and the second pair of uprights are included in the plane defining the interval between two consecutive compartments. Attached Figure Description
[0085] Other features, details, and advantages will become apparent from reading the description provided below and examining the accompanying drawings, in which:
[0086] Figure 1 This is a general perspective view of a box for a medium-voltage electrical unit according to the present invention.
[0087] Figure 2 yes Figure 1 A partial view of the box.
[0088] Figure 3 This is a detailed view showing the two columns of a box equipped with at least one reinforcing rod.
[0089] Figure 4 This is a detailed perspective view of the first embodiment of the present invention.
[0090] Figure 5 This is a detailed cross-sectional view of the second embodiment of the present invention.
[0091] Figure 6 This is a detailed perspective view of the third embodiment of the present invention.
[0092] Figure 7 This is a detailed cross-sectional view of the fourth embodiment of the present invention.
[0093] Figure 8 yes Figure 4 Detailed cross-sectional view of the first embodiment,
[0094] Figure 9 yes Figure 4 Another detailed sectional view of a variation of the first embodiment,
[0095] Figure 10 yes Figure 5 A detailed perspective view of the spacer in the second embodiment.
[0096] Figure 11 yes Figure 6 Detailed cross-sectional view of the third embodiment,
[0097] Figure 12 yes Figure 7 Detailed perspective view of the fourth embodiment,
[0098] Figure 13 This is a detailed sectional view of the fifth embodiment. Detailed Implementation
[0099] To facilitate reading the accompanying drawings, various elements are not necessarily shown to scale. In the drawings, identical elements have the same reference numerals. Some elements or parameters may be indexed, that is, indicated, for example, by "first element" or "second element," or "first parameter" and "second parameter," etc. The purpose of this indexing is to distinguish similar but not identical elements or parameters. This indexing does not imply that one element or parameter is superior to another; names can be interchanged. When a subsystem is specified to have a given element, it does not exclude the presence of other elements within that subsystem.
[0100] Figure 1 and Figure 2 The diagram shows a enclosure 50 for a medium-voltage electrical unit, designed to contain gas at a pressure greater than atmospheric pressure, the enclosure having:
[0101] -Structure 1 with columns 2
[0102] - The panel 3 is fixed to the column 2 and is configured to receive the pressure of the pressurized gas.
[0103] The components of the uprights 2 form part of the structure 1 to which the panel 3 is fixed. The panel 3 forms the outer shell of the box 50. In this case, the panel 3 is welded to the structure 1. In the example shown here, the box 50 has a generally rectangular shape. The box 50 defines an enclosed volume defined by the panel 3. The volume defined by the panel 3 is airtight. The uprights 2 extend in a first direction Z corresponding to the vertical direction. The uprights 2 are connected at each end by a tie rod 11 or a reinforcement 11 extending in a second direction X, which is transverse to the first direction Z and corresponds to the first horizontal direction. A pair of uprights 2 and a pair of reinforcements 11 form a rectangular frame. The panel 3 can be fixed to each side of the rectangular frame. A plurality of rectangular frames are arranged in a third direction Y, which corresponds to the second horizontal direction and is perpendicular to the first horizontal direction X. The structure 1 includes the components of the uprights 2 and the reinforcements 11.
[0104] The enclosure 50 can therefore contain pressurized gas, that is, gas with a pressure greater than atmospheric pressure. The gas intended to be contained within the enclosure can be a pure gas or a gas mixture. In particular, the gas intended to be contained within the enclosure can be a binary mixture. This gas can be, for example, a mixture of dry or dehumidified air, nitrogen, oxygen, and carbon dioxide, or any other gas or mixture with sufficient electrical insulating properties. The internal space of the enclosure 50 is intended to house a medium-voltage distribution unit. The term "medium voltage" is understood to refer to a voltage between 1 kV and 52 kV. This unit can be, for example, an arc-extinguishing device, such as a switch, fuse switch, circuit breaker, or disconnector. Under nominal operating conditions, the electrical unit is in contact with the pressurized gas. The inner surface of the panel 3 is also in contact with the pressurized gas. The outer surface of the panel 3 is affected by atmospheric pressure. Therefore, the force generated by the pressure difference between the inside and outside of the enclosure 50 tends to cause the panels to move away from each other. The force applied to the panels is transmitted to the structure 1, particularly the columns 2, and tends to cause them to sag.
[0105] Box 50 also features:
[0106] - At least one metal reinforcing rod 4 extending along the longitudinal direction X, the reinforcing rod 4 connecting the two columns 2 together to resist the deformation of the columns 2 under gas pressure.
[0107] -At least one first electrically insulating tube 5,
[0108] At least one longitudinal portion of the reinforcing rod 4 is surrounded by the first insulating tube 5.
[0109] The reinforcing rod 4 strengthens structure 1 by limiting the bending of the column 2 under pressure applied to the panel 3. The electrical insulation of the reinforcing rod 4 is improved by surrounding it with an insulating tube 5. This eliminates the risk of arcing between the reinforcing rod 4 and the electrical units housed in the enclosure 50. Therefore, the proposed solution provides mechanical strength compatible with the pressures employed in the enclosure while ensuring satisfactory electrical insulation. The additional costs involved are minimal and have almost no impact on the enclosure manufacturing process. Thus, the enclosure, initially designed to be filled with pressurized fluorinated gas, can be adapted to operate with non-fluorinated gases, such as air or nitrogen, which require higher pressures and have a limited number of modifications.
[0110] The reinforcing rod 4 is disposed within the first insulating tube 5 for at least a portion of its length. The end of the reinforcing rod 4 is outside the volume defined by the first insulating tube 5.
[0111] A longitudinal portion surrounded by a first insulating tube 5 is disposed between the two posts 2. The reinforcing rod 4 includes a longitudinal central portion 25 and two end portions 26, 27 located on either side of the central portion. Each post 2 is disposed between the central portion 25 and a portion of the corresponding end portion.
[0112] like Figure 8 and Figure 9 As shown, the reinforcing rod 4 and the first insulating tube 5 are coaxial. The reinforcing rod 4 and the first insulating tube 5 extend along a common axis D. D is parallel to the longitudinal direction X.
[0113] The first insulating tube 5 is installed between the two columns 2 along the longitudinal direction X.
[0114] The inner surface 7 of the first insulating tube 5 is away from the side surface 9 of the reinforcing rod 4. In other words, there is a radial gap between the reinforcing rod 4 and the first insulating tube 5. The radial gap allows for a reduction in the electric field at the outer surface 8 of the insulating tube 5. This reduces the risk of discharge propagating on the outer surface 8 of the insulating tube 5.
[0115] Based on the example shown, especially Figure 9 In this configuration, the inner surface 7 of the first insulating tube 5 faces the reinforcing rod 4. More specifically, the inner surface 7 of the first insulating tube 5 is separated from the side surface 9 of the reinforcing rod 4 by pressurized gas.
[0116] The reinforcing rod 4 and the first insulating tube 5 are configured such that the gas pressure inside the first insulating tube 5 is equal to the gas pressure outside the insulating tube 5.
[0117] According to an embodiment not shown, the first insulating tube 5 is filled with insulating foam. The insulating foam can be, for example, polyurethane, epoxy resin, or silicone resin. In other words, the radial space between the first insulating tube 5 and the reinforcing rod 4 is filled with insulating foam. The insulating foam is in contact with the inner surfaces of the reinforcing rod 4 and the first insulating tube.
[0118] Reinforcing rod 4 is straight. Reinforcing rod 4 is cylindrical. The diameter d1 of reinforcing rod 4 is between 6 and 20 mm.
[0119] The reinforcing rod 4 is connected to the column 2 of structure 1 by nuts 18. Nuts 18 are located at each end 25, 26 of the reinforcing rod 4.
[0120] like Figure 8 and Figure 3 As shown in detail, the connection between the reinforcing rod 4 and the column 2 in structure 1 has a lock nut 19, and the column 2 is pressed between the nut 18 and the lock nut 19. The pressure acting on the panel 3 and transmitted to the column causes the reinforcing rod 4 to elongate.
[0121] like Figure 3As shown in detail, the column 2 is a metal profile. In the example described here, the column 2 is a U-shaped profile. This is understood to mean that the cross-section of the profile has a U-shape. Therefore, the column 2 has two parallel and facing legs 23, which are connected to each other by a base 24. Nuts 18 connecting the column 2 and the reinforcing rod 4 are accommodated between the legs 23 of the U. The nuts 18 connecting the column 2 and the reinforcing rod 4 abut against the base 24 of the U. The first pair of opposing columns 2 are connected by at least two reinforcing rods 4, and the second pair of opposing columns 2' are connected by at least two reinforcing rods 4'. The at least two reinforcing rods 4, 4' are parallel.
[0122] In the example shown, such as Figure 2 As shown, the box 50 includes three compartments 31, 32, and 33. The reinforcing rods 4 of the first pair of uprights 2 and the reinforcing rods 4' of the second pair of uprights 2' are included in the plane defining two consecutive compartments. "Consecutive compartments" is understood to refer to adjacent compartments, i.e., compartments that are adjacent to each other. The reinforcing rods 4 of the first pair of uprights 2 define the first compartment 31 relative to the second compartment 32. The reinforcing rods 4' of the second pair of uprights 2' define the second compartment 32 relative to the third compartment 33. Electrical units (not shown) are disposed in each of the compartments 31, 32, and 33.
[0123] The reinforcing rod 4 extends laterally relative to the column 2. Figure 2 and Figure 3 In the example shown, the reinforcing rod 4 is perpendicular to the column 2.
[0124] The box 50 includes at least two opposing planes, and a reinforcing rod 4 extends between the uprights 2 fixed to the two opposing planes of the box. The reinforcing rod connects to the uprights 2 fixed to the larger panel 3 of the box 50. The side panels and front panel are not [attached to the box]. Figure 2 The structure 1 of box 50 is shown in the figure so that the structure of box 50 can be seen.
[0125] The box 50 includes two parallel uprights 2 defining a plane perpendicular to at least one panel 3, and includes two mutually parallel reinforcing rods 4 extending perpendicularly to the two uprights 2. To make the reinforcing rods 4 visible, Figure 2 The first insulating tube surrounding the upper reinforcing rod is not shown. The first insulating tube 5 is shown on the lower reinforcing rod, which means that only the end portion of the lower reinforcing rod 4 extending out of the column 2 is visible.
[0126] According to one embodiment variation, the reinforcing rod 4 is a threaded rod. In other words, the reinforcing rod 4 is threaded along its entire length. According to another variation, the reinforcing rod 4 is threaded at the first end portion 26 and the second end portion 27, and is smooth at the center portion 25 between the two end portions 26 and 27. More specifically, the portion of the reinforcing rod 4 facing the first insulating tube 4 may be smooth. In other words, the portion of the reinforcing rod 4 surrounded by the first insulating tube 5 may be smooth.
[0127] The first insulating tube 5 is cylindrical. In this case, the first insulating tube 5 is made of polypropylene. The first insulating tube 5 can also be made of thermosetting, thermoplastic, or ceramic insulating materials. These materials have good electrical insulation properties.
[0128] The outer diameter d2 of the first insulating tube 5 is between 10 and 24 mm. The thickness e of the first insulating tube 5 is between 1 and 6 mm.
[0129] like Figure 8 and Figure 11 As shown, the length L5 of the first insulating tube 5 is greater than 80% of the distance L4 between the two columns.
[0130] The ratio between the diameter d1 of the reinforcing rod 4 and the outer diameter d2 of the first insulating tube 5 is between 0.1 and 0.6.
[0131] according to Figure 5 In the second embodiment shown, the box 50 includes a second insulating tube 6, and the second insulating tube 6 surrounds the first insulating tube 5. Figure 4 , 5 The reinforcing rod 4 is not shown in Figure 7. In other words, the second embodiment differs from the first embodiment in that a second insulating tube is added. This prevents arcing or discharge between the surface of the second insulating tube 6 and the reinforcing rod 4.
[0132] exist Figure 5 In the example shown, the second insulating tube 6 and the first insulating tube 5 are coaxial. In other words, the first insulating tube 5 is disposed inside the second insulating tube 6. The second insulating tube 6 surrounds the first insulating tube 5 along its entire length. Figure 5 In the example shown, the second insulating tube 6 and the first insulating tube 5 have the same length.
[0133] The outer diameter D3 of the second insulating tube 6 is between 14 and 40 mm.
[0134] The inner surface 10 of the second insulating tube 6 is away from the outer surface 8 of the first insulating tube 5. In other words, there is a radial gap between the first insulating tube 5 and the second insulating tube 6. This radial gap allows for a further reduction in the electric field.
[0135] The inner surface 10 of the second insulating tube 6 is separated from the outer surface 8 of the first insulating tube 5 by a layer of pressurized gas. The pressure inside the first insulating tube 5 is the same as the pressure inside the second insulating tube 6. This pressure is equal to the pressure inside the box.
[0136] The box 50 has a spacer 12, which is configured to hold the first insulating tube 5 and the reinforcing rod 4 in place coaxially.
[0137] The spacer 12 has a through slot 13 for accommodating the reinforcing rod 4. The reinforcing rod 4 passes through the spacer 12 in the longitudinal direction X, which is also the direction of the axis D of the insulating tube 5.
[0138] The spacer 12 has a receiving area that is at least partially integrated into the first insulating tube 5. Therefore, a portion of the spacer 12 is radially inserted between the reinforcing rod 4 and the first insulating tube 5. Thus, the spacer 12 holds the tube 5 in place.
[0139] Spacer 12 is made of polypropylene. Spacer 12 may also be made of any other electrically insulating thermosetting, thermoplastic, or ceramic material or metal.
[0140] Spacer 12 is configured to allow pressurized gas to pass between the outside and inside of insulating tube 5. In other words, spacer 12 does not ensure a tight seal of the first insulating tube 5.
[0141] exist Figure 5 In the second embodiment shown, the housing 50 has spacers 12 configured to coaxially hold the first insulating tube 5 in place with the reinforcing rod 4, and to coaxially hold the second insulating tube 6 in place with the reinforcing rod 4. At each end, a single spacer 12 holds the first insulating tube 5 and the second insulating tube 6 in place. In other words, at each end, the same spacer holds the first insulating tube 5 and the second insulating tube 6 in place.
[0142] Spacer 12 is disposed at the axial end of the first insulating tube 5. In the second and fourth embodiments, wherein the second insulating tube 6 surrounds the first insulating tube 5, spacer 12 is disposed at the axial end of the second insulating tube 6. More specifically, spacer 12 is disposed at each axial end of the second insulating tube 6.
[0143] More specifically, Figure 10 The spacer 12 of the second embodiment is shown in detail. The spacer 12 is in the form of a stepped cylindrical ring. One axial end 28 of the second insulating tube 6 contacts the step 20 of the spacer 12.
[0144] Especially Figure 9 As shown, the inner surface of the stepped ring is in contact with the reinforcing rod 4, and the outer surface 16 of the ring is in contact with the inner surface 7 of the insulating tube 5.
[0145] In the second and fourth embodiments, which include the two insulating tubes 5 and 6 as described above, the spacer 12 has a circular groove 14 in which an axial end 15 of the first insulating tube 5 is accommodated. Figure 12 This feature is illustrated. In these embodiments, the second insulating tube 6 is held in place by the spacer 12 in the same manner as the first insulating tube 5 in the first and third embodiments.
[0146] The first spacer 12 and the second spacer 12' are respectively disposed at one axial end 15, 15' of the insulating tube 5.
[0147] According to one feature of the invention, there is an axial gap J between the spacer 12 and the column 2, through which the corresponding axial end of the reinforcing rod passes.
[0148] The third and fifth embodiments differ from the first embodiment in that a shunt 17 is added to or immediately adjacent to the first insulating tube 5. The fourth embodiment differs from the second embodiment in that a shunt 17 is added to the second insulating tube 6.
[0149] Shunt 17 is electrically insulating. Shunt 17 is made of, for example, polypropylene or any other electrically insulating thermosetting, thermoplastic, elastic, or ceramic material. Shunt 17 and insulating tube 5 are coaxial. Shunt 17 extends radially in a plane inclined relative to the longitudinal axis D of the first insulating tube 5. In the example shown, shunt 17 extends radially in a plane perpendicular to the longitudinal axis D of the first insulating tube 5. The outer diameter D4 of shunt 17 is between 15 and 150 mm. Shunt 17 allows for improved electrical insulation of the subassembly formed by reinforcing rod 4, spacer 12, and insulating tubes 5, 6. This is because the presence of shunt 17 extends the trajectory that a possible arc or discharge must traverse in order to transfer the potential of the electrical components of the electrical unit in the housing 50 to any element of the grounded housing by propagating along the outermost part of the insulating tube furthest from reinforcing rod 4.
[0150] like Figure 6 and 12 As shown, in the third and fourth embodiments, one axial end 15 of the first insulating tube 5 contacts the disc shunt 17. More specifically, each axial end 15, 15' of the first insulating tube 5 contacts the disc shunt 17.
[0151] like Figure 7 and Figure 12 As shown, one axial end 28 of the second insulating tube 6 is in contact with the disc shunt 17.
[0152] According to special Figure 6 and 12 In the example shown, spacer 12 and shunt 17 form a single-piece assembly. This assembly can be obtained by plastic injection molding. The shunt may include protrusions (not shown) designed to extend the trajectory of the leakage path that the arc must travel.
[0153] according to Figure 13 In the fifth embodiment shown, the first insulating tube 5 is surrounded by a disc-shaped insulating shunt 17. In other words, a portion of the first insulating tube 5 extends along the longitudinal direction X on either side of the insulating shunt 17.
[0154] The insulating shunt 17 is located away from the axial end 15 of the first insulating tube 5. The contact area between the outer surface of the first insulating tube 5 and the shunt 17 extends continuously over 360°. Furthermore, the contact area between the first insulating tube 5 and the shunt 17 is sealed. For example, the insulating shunt 17 can be an integral part of the insulating tube. In other words, the insulating shunt and the insulating tube can form a single assembly. The insulating shunt 17 can also be attached to the periphery of the first insulating tube 5.
[0155] The insulating tube 5 is surrounded by a shunt 17 near each end. Additional shunts may be added along the insulating tube.
[0156] according to Figure 11 In the third embodiment shown, the diverter 17 is adjacent to the column 2. The distance between the diverter 17 and the column 2 is between 1 and 30 mm.
[0157] According to an embodiment not shown:
[0158] - The second insulating tube 6 may be surrounded by the disc-shaped shunt 17. This embodiment is similar to the fifth embodiment, and the shunt 17 surrounds the tube furthest from the rod 4, thus surrounding the second insulating tube 6.
[0159] - Reinforcing rod 4 can be fixed to the column with rivets.
[0160] - The reinforcing rod 4 can be fixed to the column by a flexible locking connection element.
[0161] - When the space radially located between the first insulating tube 5 and the reinforcing rod 4 is filled with insulating foam, the first insulating tube 5 can maintain a certain distance from the reinforcing rod 4 through the insulating foam.
[0162] - Box 50 may have two compartments defined by one or more reinforcing bars. Box 50 may also have three or more compartments defined by one or more reinforcing bars.
Claims
1. A enclosure (50) for a medium-voltage electrical unit, designed to contain a gas at a pressure greater than atmospheric pressure, said enclosure having: - A structure (1) with columns (2). - A panel (3) fixed to the column (2), the panel (3) being configured to receive the pressure of the pressurized gas. - At least one metal reinforcing rod (4) extending in the longitudinal direction (X), the reinforcing rod (4) connecting the two columns (2) together to resist the deformation of the columns (2) under gas pressure. - At least one first insulating tube (5). in, At least one longitudinal portion of the reinforcing rod (4) is surrounded by a first insulating tube (5), wherein the inner surface (7) of the first insulating tube (5) is away from the side surface (9) of the reinforcing rod (4).
2. The box according to claim 1, wherein, The reinforcing rod (4) and the first insulating tube (5) are coaxial.
3. The box according to claim 1 or 2, wherein, The first insulating tube (5) is disposed between the two columns (2) along the longitudinal direction (X).
4. The box according to claim 1 or 2, wherein, The box is configured such that the inner surface (7) of the first insulating tube (5) is separated from the side surface (9) of the reinforcing rod (4) by pressurized gas.
5. The box according to claim 1 or 2, wherein, The first insulating tube (5) is filled with insulating foam.
6. The box according to claim 1 or 2, wherein, The ratio between the diameter (d1) of the reinforcing rod (4) and the outer diameter (d2) of the first insulating tube (5) is between 0.1 and 0.
6.
7. The box according to claim 1 or 2, having a spacer (12) configured to hold the first insulating tube (5) and the reinforcing rod (4) in place coaxially.
8. The box according to claim 1 or 2, comprising a second insulating tube (6), wherein the second insulating tube (6) surrounds the first insulating tube (5), wherein the second insulating tube (6) and the first insulating tube (5) are coaxial, and wherein the inner surface (10) of the second insulating tube (6) is away from the outer surface (8) of the first insulating tube (5).
9. The box according to claim 8, wherein, The inner surface (10) of the second insulating tube (6) is separated from the outer surface (8) of the first insulating tube (5) by pressurized gas.
10. The box according to claim 1 or 2, wherein, The first insulating tube (5) is surrounded by an insulating disc shunt (17) which extends radially in a plane inclined relative to the longitudinal axis (D) of the first insulating tube (5).
11. The box according to claim 8, wherein, One axial end (15) of the first insulating tube (5) contacts an insulating disc shunt (17) which extends radially in a plane inclined relative to the longitudinal axis (D) of the first insulating tube (5).
12. The box according to claim 11, wherein, Each axial end (15, 15') of the first insulating tube (5) is in contact with the insulating disc shunt (17).
13. The box according to claim 11, having a spacer (12) configured to coaxially hold the first insulating tube (5) and the reinforcing rod (4) in place, and coaxially hold the second insulating tube (6) and the reinforcing rod (4) in place, wherein, The spacer (12) and the insulating disc shunt (17) form a single-piece assembly.
14. The box according to claim 1 or 2, wherein, The reinforcing rod (4) is connected to the column (2) of the structure (1) by a nut (18).