Switchgear for switching high voltages

Abstract

The invention relates to a switchgear (1) for switching high voltages, said switchgear comprising: at least one housing (2), wherein at least one interrupter unit (3) is located in the at least one housing (2); and at least one driving mechanism (4). The at least one driving mechanism (4) is located outside the at least one housing (2) and is connected to the at least one interrupter unit (3) in the at least one housing (2) via elements of a kinematic chain (5). At least one element (6) of the kinematic chain (5) is movably guided into the housing (2) via at least one bellows (7).

Description

[0001] Description

[0002] Switching device for switching high voltages

[0003] The invention relates to a switching device for switching high voltages, comprising at least one housing, wherein at least one interrupter unit is arranged in the at least one housing, and comprising at least one actuator. The at least one actuator is arranged outside the at least one housing and is connected to the at least one interrupter unit in the at least one housing via elements of a kinematic chain.

[0004] Switching devices for switching high voltages are designed to switch currents while simultaneously isolating voltages in the range of 52 kV or greater. They comprise one or more interrupter units, each with at least one pair of two contact elements movable relative to each other. These contact elements, located in an insulating medium, e.g., an insulating gas or in a vacuum, connect to close a current path and separate to open it. The respective contact elements of an interrupter unit are arranged in a casing, in particular an insulator or a metal tank, or a casing comprising a metal and an insulator, in particular a ceramic.

[0005] The interrupter unit(s) of a switching device are arranged in a housing. An actuator is located, for example, outside the housing, and the movable contact elements of the interrupter unit(s) are driven during switching via elements of a kinematic chain, such as gear components and at least one switching rod. Actuators include, for example, motors, spring accumulators, and / or linear actuators. During switching, the energy of the actuator is transferred from the actuator via the elements of the kinematic chain into the housing of the switching device to the movable contact elements of the interrupter unit(s).

[0006] The housing of the switching device is filled, for example, with an insulating gas, particularly under ambient, positive, or negative pressure, to electrically insulate the interrupter unit and its external contacts from the housing. To ensure a pure, pressure-stable insulating gas remains permanently inside the housing, it is designed to be gas-tight. Seals, such as rubber seals, are used to create a gas-tight seal for components like a switching rod, which is part of the kinematic chain, connecting the drive mechanism to the housing. These seals are subject to energy losses due to kinetic energy, and they weather and become brittle over time, leading to increased susceptibility to failure and higher maintenance costs for the switching device.

[0007] The invention is based on the objective of solving the problems described above. In particular, the invention is based on the objective of providing a switching device for switching high voltages which requires little maintenance, incurs low costs, and ensures a constant insulating medium pressure, in particular gas pressure, permanently within the switching device housing, with a low risk of contamination of the insulating medium.

[0008] The problem is solved according to the invention by a switching device for switching high voltages with the features of claim 1.

[0009] Advantageous embodiments of the invention are the subject of the dependent claims.

[0010] A switching device according to the invention for switching high voltages comprises at least one housing, wherein at least one interrupter unit is arranged in the at least one housing, and comprises at least one actuator. The at least one actuator is arranged outside the at least one housing and is connected to the at least one interrupter unit in the at least one housing via elements of a kinematic chain. At least one element of the kinematic chain is movably guided into the housing via at least one bellows.

[0011] The bellows enables a switching device with a gas-tight sealed housing, eliminating the disadvantages of rubber seals, particularly the high maintenance costs associated with regular inspections and replacements. The use of a bellows maintains a constant insulating medium pressure, especially insulating gas, within the switching device housing, minimizing the risk of contamination by ambient air particles or seal abrasion. A bellows is permanently stable, has a long service life, is flexible, and allows the switching motion from the actuator outside the gas-tight housing to the interrupter unit inside with minimal or no loss.

[0012] The switching device can be a dead-tank high-voltage circuit breaker, particularly with a metal tank as its housing, or a column-shaped high-voltage open-air circuit breaker, particularly with an insulator as its housing. The insulator is, for example, a finned insulator made of ceramic, silicone, and / or a composite material. In dead-tank high-voltage circuit breakers and high-voltage open-air circuit breakers, the interrupting unit is located inside a housing, and the actuator is, for example, located outside. The advantages are thus as described above.

[0013] The interrupter unit can at least one

[0014] The vacuum interrupter tube and / or at least one switching gas interrupter unit, in particular with rated current and / or arc contacts, are included. Switching gas interrupter units are arranged in a gas-tight housing filled with switching gas or insulating gas as the insulating medium. Vacuum interrupter tubes are arranged, for example, in an outer housing of a switching device, e.g., with a housing filled with an insulating gas. Insulating gases include, for example, SF6, CO2, or clean air, i.e., purified, dried air. Alternatively, a vacuum can be used instead of an insulating gas. To ensure a gas-tight housing in which elements of the kinematic chain are enabled to transport the kinetic energy from the drive outside the housing to the interrupter unit inside the housing, at least one element of the kinematic chain must be movably mounted from the outer to the inner housing, e.g.,In the prior art, seals are used, and according to the invention, a bellows is used. In the case of a vacuum interrupter tube as the interrupting unit, the vacuum interrupter tube has a bellows, and the housing of the switching device has at least a second bellows. This combines the advantages described above.

[0015] The housing can be sealed gas-tight by the bellows, in particular filled with an insulating gas comprising SF6, CO2, and / or purified, dried air. This ensures good electrical insulation of the interrupter unit. When using environmentally harmful gases, such as SF6, gas leakage from the switching device housing is prevented. Contaminants and moisture, e.g., from the ambient air, do not penetrate the switching device housing. Thus, long-term stable, reliable, and low-maintenance operation of the switching device is possible.

[0016] The at least one element of the kinematic chain, which is movably guided into the housing via the at least one bellows, can be a switching rod, in particular a switching rod made of highly conductive metal or a switching rod made of an insulator, especially an electrically insulating plastic. A switching rod is cost-effective and can be movably guided gas-tight by a bellows. With a metallic switching rod, electrical contact with the breaker unit or contact elements of the breaker unit is possible; with a switching rod made of an insulator, currentless and potential-free guidance of the switching rod is possible, whereby electrical contact with the breaker unit is possible via contacts which are led out of the housing, e.g., via electrical bushings.

[0017] A bellows is typically subjected to varying degrees of mechanical stress along its length. The mechanical stress on a particular section of the bellows therefore generally depends on its location along the bellows' length. For example, the ends of the bellows are often subjected to particularly high stress. This effect can be amplified by transverse forces acting on the bellows, which can be caused, for instance, by imperfect bellows alignment or, especially in the case of a horizontally mounted bellows, by gravity.

[0018] The variation in the pleat structure of the bellows can counteract uneven loading of the bellows along the longitudinal axis of at least one element of the kinematic chain. The pleat structure of the bellows along the longitudinal axis of an element of the kinematic chain, in particular a switching rod, which is guided from the outside into the interior of the switching device housing through the bellows, is designed such that it compensates for uneven loading of the bellows along the longitudinal axis of the contact element. This increases the service life, especially with frequent switching of the bellows and thus of the switching device, and reduces maintenance work, thereby lowering costs.

[0019] The fold height h of the bellows folds along the longitudinal axis of at least one element of the kinematic chain can vary. The fold height h of the bellows folds can be smaller in a first region of the bellows than in a second region of the bellows that is subjected to less stress. The fold height h of the bellows folds can decrease towards the first end and / or the second end of the bellows compared to a central region. This is associated with the advantages described above.

[0020] The pleat spacing d between two adjacent pleats of the bellows along the longitudinal axis of at least one element of the kinematic chain can vary, whereby in particular the pleat spacing d in a first region of the bellows can be smaller than in a second region of the bellows that is subjected to less stress than the first region. The pleat spacing d towards the first end and / or the second end of the bellows can increase compared to a central region of the bellows. This results in the advantages described above, in particular a long service life of the bellows.

[0021] The material thickness b of the bellows along the longitudinal axis of a kinematic chain element, particularly a shift rod, can vary. The material thickness b of the bellows folds can be smaller in a first region of the bellows than in a second region that is subject to less stress. The material thickness b towards the first end and / or the second end of the bellows can increase compared to a central region. This allows for the creation of a long-life bellows with minimal material usage, thus saving costs.

[0022] The bellows can be made of a metallic material, particularly stainless steel. Metals, especially stainless steels, are stable over long periods even with frequent deformation, and in particular, they do not break. This allows for a robust bellows design and thus a long service life.

[0023] A bellows in the housing of a switching device is generally larger than a bellows in, for example, a vacuum interrupter. During switching, lateral movement perpendicular to the longitudinal axis of, for example, a switching rod, is to be expected in the housing area. This movement places considerable stress on the bellows and can lead to a reduced service life. Therefore, in the prior art, sealing material, such as rubber seals, is used in the housing area. The use of a standard bellows, as known from vacuum interrupter manufacturing, is not possible. Only the further development and special adaptation of bellows enables their use in the housing of a switching device.

[0024] The properties, features, and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more readily understandable in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the drawings. These show:

[0025] FIG 1 shows a schematic sectional view of an embodiment of the switching device 1 according to the invention, with a bellows 7 on or in a metal tank as housing 2, in dead-tank construction, and

[0026] FIG 2 shows a schematic sectional view of an embodiment of the switching device 1 according to the invention, with a bellows 7 on or in a ribbed insulator as housing 2, in a column-shaped open-air switch design, and

[0027] FIG 3 shows a schematic sectional view of a first embodiment of a bellows 7 of a switching device 1 according to the invention, and

[0028] FIG 4 shows a schematic sectional view of a second embodiment of a bellows 7 of a switching device 1 according to the invention, and

[0029] FIG 5 shows a schematic sectional view of a third embodiment of a bellows 7 of a switching device 1 according to the invention, and

[0030] FIG 6 shows a schematic sectional view of a fourth embodiment of a bellows 7 of a switching device 1 according to the invention.

[0031] Corresponding parts in the figures are marked with the same reference symbols.

[0032] Figure 1 (FIG 1) shows a schematic sectional view of an embodiment of a switching device 1 according to the invention. The switching device 1 is exemplary designed as a dead tank with a cylindrical-tank-shaped housing 2. In addition to the housing 2, the switching device 1 has an actuator 4, which is arranged outside the housing 2. An interrupter unit 3 is arranged in the housing 2, e.g., a vacuum interrupter tube and / or an interrupter unit having a rated current and / or arc contact. Alternatively, further interrupter units 3, e.g., connected in series, can also be arranged in the housing 2, in particular with further elements, such as capacitors, resistors, varistors, and / or surge arresters as control elements. The switching device 1 can have further components that are not shown in Figure 1 or not shown in detail, as they are not relevant to the invention, e.g., a stand rod under the housing 2 .The interrupter unit 3 is held in the housing 2 e.g. by brackets and is electrically contacted to the outside e.g. via contact rods which run through openings in the housing 2 .

[0033] Elements of a kinematic chain 5 mechanically connect the drive 4 to the interrupter unit 3. The kinematic chain 5 comprises, for example, gear components, at least one drive rod or shaft, and / or deflection elements. An element 6 of the kinematic chain 5, in particular a shift rod, is movably guided from the outside of the housing 2 into the interior of the housing 2 by at least one bellows 7. For higher safety requirements or frequent switching and the associated high mechanical loads, more than one bellows 7 can be used, in particular bellows 7 arranged one behind the other or nested within each other.

[0034] When the switching device 2 is switched, particularly when switching on or off, mechanical kinetic energy is provided by the drive 4, e.g., a motor or spring-loaded drive, and transferred to the interrupter unit 3 via the elements of the kinematic chain 5. In the area of ​​the bellows 7, the bellows 7, particularly by stretching or compressing the folds, enables the transfer of kinetic energy from the outside to the inside of the gas-tight housing 2 via the element 6 of the kinematic chain 5, in particular the switching rod, which is gas-tightly connected to the bellows 7. Through the movement of the folds and, for example, the spring-like properties of the bellows 7, a transfer of kinetic energy is possible with low losses.

[0035] Figure 2 (FIG 2) shows a schematic sectional view of an alternative embodiment of a switching device 1 according to the invention. The switching device 1 is exemplary configured as a column-shaped outdoor switch with a ribbed, cylindrical insulator housing 2. Alternatively, and not shown in the figures for the sake of simplicity, the switching device 1 is configured in a different form, with more than one insulator housing, e.g., T-shaped. In addition to the housing 2, in particular made of silicone, ceramic, and / or a composite material, the switching device 1 has an actuator 4, which is arranged outside the housing 2. An interrupter unit 3 is arranged in the housing 2, e.g., a vacuum interrupter tube and / or an interrupter unit having a rated current and / or arc contact. Alternatively, further interrupter units 3, e.g., connected in series, can also be arranged in the housing 2, in particular with further elements, such as...Capacitors, resistors, varistors, and / or surge arresters as control elements.

[0036] The switching device 1 may include further components that are not shown, or not shown in detail, in Figure 1, as they are not relevant to the invention. For example, a stator linkage under the housing 2, on which the housing 2 is arranged and on which, for example, the drive 4 is arranged. Elements of the kinematic chain 5, such as linkages, drive rods, deflection levers, and gear parts, may be arranged in and / or on the stator linkage. The interrupter unit 3 is held or suspended in the housing 2, for example, by a bracket, and is electrically connected to the outside, for example, via the bracket and / or electrical lines. For the sake of simplicity, this is not shown, or not shown in detail, in Figure 2.

[0037] Elements of a kinematic chain 5 mechanically connect the drive 4 to the interrupter unit 3. The kinematic chain 5 comprises, for example, gear components, drive rods or shafts, and / or deflection elements. An element 6 of the kinematic chain 5, in particular a shift rod, is movably guided from the outside of the housing 2 into the interior of the housing 2 by at least one bellows 7. For higher safety requirements or frequent switching and the associated high mechanical loads, more than one bellows 7 can be used, in particular bellows 7 arranged one behind the other or nested within each other.

[0038] When the switching device 2 is switched, particularly when switched on or off, mechanical kinetic energy is provided by the drive 4, e.g., a motor or spring-loaded drive, and transferred to the interrupter unit 3 via the elements of the kinematic chain 5. In the area of ​​the bellows 7, the bellows 7, particularly by stretching or compressing the folds, enables the transfer of kinetic energy from the outside to the inside of the gas-tight housing 2 via the element 6 of the kinematic chain 5, in particular the switching rod, which is gas-tightly connected to the bellows 7. Through the movement of the folds and, for example, the spring-like properties of the bellows 7, a transfer of kinetic energy is possible with minimal losses.

[0039] The bellows 7 of Figures 1 and 2 is attached to or located in the housing 2 and is gas-tightly connected to the housing 2, for example, in a round recess in the housing 2, facing inwards or outwards. The bellows 7 is, for example, soldered, glued, clamped, and / or welded to the housing. The movable element 6 of the kinematic chain 5, in particular the switching rod, is guided through the bellows 7 and gas-tightly connected to the bellows 7, for example, by soldering, gluing, clamping, and / or welding.

[0040] Figures 3 to 6 show exemplary embodiments of the bellows 7 in more detail. The bellows 7 is arranged in the housing 2 as shown in Figures 1 and 2, which is not shown in Figures 3 to 6 for the sake of simplicity. A first end 12 of the bellows 7 is, for example, fixedly connected to the element 6 of the kinematic chain 5. A second end 13 of the bellows 7, opposite the first end 12, is fixedly connected to the housing 2 of the switching device 1 and surrounds a housing opening. The bellows 7 seals the housing 2 gas-tight against the environment of the switching device 1. For example, the bellows 7 is made of a metallic material, in particular stainless steel. The first end 12 of the bellows 7 is connected to the element 6, for example, by soldering, gluing, welding, and / or clamping.The second end 13 of the bellows 7 is connected to the housing 2, for example, by soldering, gluing, welding, screwing and / or clamping.

[0041] The bellows 7 has folds 8 extending around a longitudinal axis 9 of the element 6, with a fold structure that varies along the longitudinal axis 9. The fold structure is not shown in Figures 1 and 2. Exemplary embodiments of the bellows 7 with different fold structures are shown in Figures 3 to 6. In each of these figures, sectional views of a portion of the bellows 7 are shown. The fold structure of the bellows 7 counteracts an uneven mechanical load on the bellows 7 along the longitudinal axis 9. Figures 3 to 6 each show an exemplary embodiment of a bellows 7 in which the mechanical load in a region 10 is greater than in a region 11. In these exemplary embodiments, each region 10 is an end region of the bellows 7, and the region 11 is, for example,A central region of the bellows 7, wherein the region 10 on the right side of each figure comprises the first end 12 of the bellows 7 and the region 10 on the left side of each figure comprises the second end 13 of the bellows 7. In other embodiments, however, regions 10 and 11 may be other regions of the bellows 7.

[0042] Figure 3 (FIG 3) shows a first embodiment of the bellows 7. In this embodiment, the fold height h of the folds 8 of the bellows 7 varies along a longitudinal axis 9. The fold height h of the folds 8 of the bellows 7 decreases in the region 10 towards the first end 12 of the bellows 7 and in the region 10 towards the second end 13 of the bellows 7 compared to the region 11 of the bellows 7. The fold height h of a fold 8 denotes the difference between the maximum and minimum distance of a fold surface of the fold 8 from the longitudinal axis 9.

[0043] Figure 4 (FIG 4) shows a second embodiment of the bellows 7. In this embodiment, the pleat spacing d between two adjacent pleats 8 of the bellows 7 varies along the longitudinal axis 9. The pleat spacing d increases in the region 10 towards the second end 13 of the bellows 7 compared to the region 11 of the bellows 7.

[0044] Figure 5 (FIG 5) shows a third embodiment of the bellows 7. In this embodiment, the material thickness b of the folds 8 of the bellows 7 varies along the longitudinal axis 9. The material thickness b of the folds 8 of the bellows 7 increases in the region 10 towards the first end 12 of the bellows 7 and in the second region 10 towards the second end 13 of the bellows 7 compared to the region 11 of the bellows 7.

[0045] Figure 6 (FIG 6) shows a fourth embodiment of the bellows 7. In this embodiment, the fold height h, the fold spacing d, and the material thickness b of the folds 8 of the bellows 7 vary along the longitudinal axis 9. The fold spacing d and the material thickness b increase in region 10 towards the first end 12 of the bellows 7 compared to region 11 of the bellows 7. In region 10, the fold height h decreases towards the second end 13 of the bellows 7 compared to region 11 of the bellows 7, and the fold spacing d increases towards the second end 13 of the bellows 7 compared to region 11 of the bellows 7. The embodiments described above can be combined with each other and / or with the prior art. Thus, different types of switching devices are possible, e.g. Dead-tank, live-tank and / or open-air switches, especially for high voltages for switching direct and / or alternating current.The switching devices 1 are designed for switching one or more phases. One or more interrupter units 3 are arranged in the switching device 1, in particular with control elements such as capacitors, resistors, varistors and / or surge arresters. The interrupter units are or comprise, for example, vacuum interrupters, gas switches with rated current contacts and / or with arc contacts, with and without an additional casing or housing.

[0046] The bellows 7 can be used individually or in combination. For example, bellows 7 can seal several chambers in a housing 2 or the housing 2 to the outside. The bellows 7 is made, for example, of stainless steel and / or metal alloys. The advantage of using a bellows 7, for example, instead of a seal, especially one made of rubber, for gas-tight sealing of the housing 2 and for guiding at least one element 6 of the kinematic chain 5, is, for example, its high long-term stability, service life, resilient properties, no abrasion, low cost, and low maintenance requirements with good sealing properties.

[0047] Reference character list

[0048] 1 switching device for switching high voltages

[0049] 2 Housings 3 Interrupter unit

[0050] 4 Drive

[0051] 5 kinematic chain

[0052] 6 Element of the kinematic chain, which is guided into the housing via a bellows 7 Bellows

[0053] 8 folds

[0054] 9 Longitudinal axis

[0055] 10 first area

[0056] 11 second area / middle area 12 first end

[0057] 13 second end

Claims

Patent claims 1. Switching device (1) for switching high voltages, comprising at least one housing (2) , wherein at least one interrupter unit (3) is arranged in the at least one housing (2) and comprising at least one drive (4) , wherein the at least one drive (4) is arranged outside the at least one housing (2) and is connected to the at least one interrupter unit (3) in the at least one housing (2) via elements of a kinematic chain (5) , characterized in that at least one element (6) of the kinematic chain (5) is movably guided into the housing (2) via at least one bellows (7).

2. Switching device (1) according to claim 1, characterized in that the switching device (1) is a dead-tank high-voltage circuit breaker, in particular with a metal tank as housing (2), or a high-voltage free-air switch in column form, in particular with an insulator as housing (2).

3. Switching device (1) according to one of the preceding claims, characterized in that the interrupter unit (3) comprises at least one vacuum switching tube and / or at least one switching gas interrupter unit, in particular with rated current and arc contacts.

4. Switching device (1) according to one of the preceding claims, characterized in that the at least one housing (2) is sealed gas-tight by the at least one bellows (7), in particular filled with an insulating gas comprising SF6, CO2, and / or purified, dried air.

5. Switching device (1) according to one of the preceding claims, characterized in that the at least one element (6) of the kinematic chain (5) which has at least a bellows (7) is movably guided into the housing (2), a switching rod, in particular a switching rod made of highly conductive metal or a switching rod made of an insulator, in particular of an electrically insulating plastic or composite material.

6. Switching device (1) according to one of the preceding claims, characterized in that the variation of the fold structure of the folds (8) of the bellows (7) counteracts an uneven load on the bellows (7) along the longitudinal axis (9) of the at least one element (6) of the kinematic chain (5).

7. Switching device (1) according to one of the preceding claims, characterized in that a fold height (h) of the The folding (8) of the bellows (7) along the longitudinal axis (9) of the at least one element (6) of the kinematic chain (5) varies.

8. Switching device (1) according to claim 7, characterized in that the fold height (h) of the folds (8) of the bellows (7) in a first area (10) of the bellows (7) is smaller than in a second area (11) of the bellows (7) which is less stressed compared to the first area (10).

9. Switching device (1) according to claim 7 or 8, characterized in that the fold height (h) of the folds (8) of the bellows (7) decreases towards the first end (12) and / or the second end (13) of the bellows (7) compared to a central area (11) of the bellows (7).

10. Switching device (1) according to one of the preceding claims, characterized in that a fold spacing (d) of two adjacent folds (8) of the bellows (7) varies along the longitudinal axis (9) of the at least one element (6) of the kinematic chain (5), wherein in particular the fold spacing (d) in a first region (10) of the bellows (7) is smaller than in a region (10) compared to the first Area (10) is the less stressed second area (11) of the bellows (7).

11. Switching device (1) according to claim 10, characterized in that the pleat spacing (d) towards the first end (12) and / or the second end (13) of the bellows (7) increases relative to a central area (11) of the bellows (7).

12. Switching device (1) according to one of the preceding claims, characterized in that a material thickness (b) of the bellows (7) varies along the longitudinal axis (9) of the at least one element (6) of the kinematic chain (5).

13. Switching device (1) according to claim 12, characterized in that the material thickness (b) of the folds (8) of the bellows (7) in a first area (10) of the The bellows (7) is smaller than in a second area (11) of the bellows (7) which is less stressed compared to the first area (10).

14. Switching device (1) according to claim 12 or 13, characterized in that the material thickness (b) to the first end (12) and / or to the second end (13) of the bellows (7) towards a middle area (11) of the bellows (7) increases.

15. Switching device (1) according to one of the preceding claims, characterized in that the bellows (7) is made of a metallic material, in particular of stainless steel.

Images