DEVICE AND METHOD FOR VIBRATION DAMPING IN HIGH-VOLTAGE EQUIPMENT

Description

[0001] The invention relates to a device and a method for vibration damping in high-voltage equipment, with a support arrangement for the high-voltage equipment, which comprises support elements that are connected to each other via connecting elements.

[0002] Devices for high-voltage equipment, particularly for equipment in the range of up to 1200 kV, are known, for example, from EP 0 783 078 A2 and US 2012 / 131877 A1. These devices include, for example, high-voltage cables mounted on overhead line masts as devices for high-voltage equipment made of steel profile lattice bars. Other high-voltage equipment includes, for example, instrument transformers, high-voltage circuit breakers, and / or disconnectors, which are arranged on supports or support assemblies made of steel profile lattice bars as devices for high-voltage equipment. The lattice bars of the support assembly, e.g., made of steel, as load-bearing elements, have, in particular, an L-, T-, and / or double-T profile and are connected to each other by connecting elements, in particular screws and nuts. Intermediate elements, e.g.,Washers, as known from JP 2011 162943 A, JP H06 323325 A, US 2016 / 076581 A1 and DE 296 19 383 U1, transfer a clamping force from the bolted connection to the grid bars and, via a preload force, result in a mechanically rigid connection between the grid bars. US 6129326 A discloses a bolted connection with an assembly between two components, one of which can be subject to vibrations. The assembly comprises a stack of washers bonded together.

[0003] The screws, acting as connecting elements, are mechanically fixed in bores of the grid bars. However, embrittlement can occur in the area of ​​these bores, potentially leading to grid bar breakage under mechanical stress, such as wind. To prevent this, the preload force of the screw connection is distributed across areas of the grid elements that do not become brittle, thanks to the shape of the washers used as intermediate elements. This results in a long-term stable, strong, and rigid mechanical connection between the grid elements, which serve as load-bearing elements of the support structure for the high-voltage equipment.

[0004] When the devices are subjected to mechanical stress, e.g., from wind and / or earthquakes, a portion of the stress is absorbed by the elasticity of the supporting elements. Elastic areas of the supporting elements can deform elastically and / or plastically, thereby absorbing mechanical energy transferred to the device by wind and / or earthquakes and converting it, for example, into heat energy. Large elastic and / or plastic deformations of the supporting elements, especially over extended periods and / or with frequent occurrence, lead to the failure of supporting elements, resulting in irreversible damage and / or failure of the device and consequently, a failure of the high-voltage system. Damping devices in the foundation, e.g., using large springs, can absorb mechanical energy, but are complex and expensive.

[0005] The object of the present invention is to provide a device and a method for vibration damping in high-voltage equipment that solves the problems described above. In particular, it is an object to achieve simple, cost-effective, and effective vibration damping in order to prevent irreversible damage to the device and thus to the high-voltage equipment, especially in the presence of environmental influences such as wind and / or earthquakes.

[0006] The stated problem is solved according to the invention by a device for vibration damping in high-voltage equipment according to claim 1 and by a method for vibration damping in high-voltage equipment, in particular using a previously described device, according to claim 14. Advantageous embodiments of the device for vibration damping in high-voltage equipment according to the invention and / or the method for vibration damping in high-voltage equipment, in particular using a previously described device, are specified in the dependent claims. The subject matter of the main claims can be combined with each other and with features of the dependent claims, as well as with each other.

[0007] An inventive device for vibration damping in high-voltage installations comprises a support arrangement for elements of the high-voltage installation with support elements that are connected to one another via connecting elements. Intermediate elements are arranged between the connecting elements and the support elements and / or between different support elements, which are designed to effect vibration damping.

[0008] By arranging intermediate elements between the support elements and / or between the connecting elements and the support elements, simple, cost-effective, and efficient vibration damping is achieved. This prevents irreversible damage to the device and thus to the high-voltage equipment, particularly from environmental influences such as wind and / or earthquakes. The intermediate elements are designed to absorb movements or vibrations of the device according to the invention in conjunction with the connecting elements and / or support elements, for example, by converting the vibrational energy into frictional heat. In contrast to the prior art, vibrations in the device according to the invention are not damped exclusively by elastic and / or plastic deformations of the support elements.The intermediate elements not only absorb kinetic energy when the load-bearing elements are rigidly connected via prestressed connecting elements, but also absorb it in conjunction with the load-bearing and / or connecting elements.

[0009] The intermediate elements are coated washers that enable a mechanically rigid connection between the load-bearing elements via the connecting elements, while simultaneously allowing flexibility regarding movement of the load-bearing elements relative to each other, particularly under strong forces, e.g., wind and / or earthquakes, through sliding friction between the intermediate elements and the load-bearing and / or connecting elements. A stack of different intermediate elements—one coated for lower friction and one with higher friction—forms a damping element for mechanical vibrations in conjunction with at least one load-bearing element and at least one connecting element. This can be achieved with a stack of different intermediate elements between two load-bearing elements and / or a stack of different intermediate elements between each load-bearing element and a connecting element.The coating of the washers, in conjunction with the mechanical preload of the connecting elements, enables a predetermined setting of the friction between intermediate elements and the load-bearing and / or connecting elements, and thus a defined damping of movements or vibrations between load-bearing elements depending on the coefficients of static and / or kinetic friction of the coating of the intermediate elements with the materials of the load-bearing and / or connecting elements.

[0010] The intermediate elements can be coated with a polymer, in particular Teflon, PTFE, and / or PCTFE, a metal, in particular silver, and / or graphite. This achieves a stable mechanical connection between the load-bearing elements via static friction between the coated intermediate elements and the load-bearing and / or connecting elements. Under high forces caused by movements or vibrations between load-bearing elements, the coated intermediate elements allow flexible movement of the load-bearing elements relative to each other, absorbing kinetic or vibrational energy by overcoming static friction and through sliding friction. The energy is converted into heat and dissipated into the environment, in particular the ambient air, without leading to irreversible plastic deformation or breakage of the load-bearing elements. The type of coating, i.e.,By adjusting the surface roughness and / or the material choice of the coating, the coefficient of static and kinetic friction between the elements can be predetermined, which, in conjunction with the preload force of the connecting elements, allows the stiffness of the device, the damping constant and the energy absorption to be adjusted, particularly depending on the vibration amplitude and / or frequency.

[0011] The coating of the intermediate elements can have a specific coefficient of sliding friction on the material of the supporting elements, particularly in the range of 0.01 to 0.3 and / or in the range greater than 1. A specific coefficient of sliding and / or static friction enables a device according to the invention with predetermined mechanical stiffness, which dampens movements or vibrations in a predetermined manner above certain occurring forces. With a low coefficient of sliding friction, even smaller forces, e.g., in wind, can be absorbed, especially also in the case of vibrations of higher frequency. With a low coefficient of sliding friction, larger forces, e.g., in the case of earthquakes, can be absorbed, especially in the case of vibrations of lower frequency. The device is nevertheless stiffer than when using most damping systems known from the prior art. There is essentially no change in the natural frequency of the support arrangement.

[0012] The intermediate elements can be washers made of an elastic material, in particular plastic and / or rubber, and / or include washers. This also allows for vibration damping via the intermediate elements.

[0013] The support structure can be a lattice tower, in particular a steel lattice tower, and / or a T-shaped tower. Lattice towers offer good load-bearing capacity at low cost and with minimal material expenditure, e.g., for power lines. T-shaped towers are towers with arms, especially two or more arms.

[0014] The load-bearing elements can be T-beams, I-beams, and / or L-beams, especially made of steel. T-beams and / or I-beams, especially those made of steel, offer high mechanical stiffness, long-term stability, and mechanical strength at a relatively low self-weight.

[0015] The connecting elements can be screws with nuts and / or bolts, especially made of steel. This allows for stable mechanical connections with high preloads. With screw connections, the preload can be precisely controlled, and thus the damping of the device can be precisely adjusted via the preload and, in particular, via the coating and material selection of the connecting elements.

[0016] The connecting elements can be designed to connect the load-bearing elements via openings in the load-bearing elements, in particular through-holes. This allows for a cost-effective connection of load-bearing elements, e.g., via bolts and / or screws with nuts, supported through or within the holes.

[0017] The openings can be designed such that the connecting elements are movably mounted in the supporting elements, in particular with one degree of freedom with respect to movement depending on a vibration to be damped and / or a specific earthquake threshold. The connecting elements can have a clearance in the openings ranging from micrometers to millimeters. In conjunction with the number of openings or connecting elements, the preload, and the coefficient of friction, the mechanical strength, stiffness, and absorption of kinetic energy of the device according to the invention can be specifically adjusted via this clearance, which ranges from micrometers to millimeters.

[0018] At least one intermediate element, in particular two different intermediate elements, in conjunction with at least one support element, in particular with two support elements, and with at least one connecting element, in particular at least two different connecting elements, can form a damping element for mechanical vibrations. The friction of the elements against each other yields the damping constant of the damping element for mechanical vibrations.

[0019] A stack of different intermediate elements, in particular an intermediate element with a coating and an intermediate element for higher friction, e.g., without a coating or with a coating having a higher coefficient of sliding friction, can, in conjunction with two support elements and at least one connecting element, form a damping element for mechanical vibrations. This is particularly possible with a stack of different intermediate elements between two support elements and / or a stack of different intermediate elements between each support element and a connecting element. A damping rate of the device can be specifically adjusted via a stack of different intermediate elements, particularly those with different coefficients of sliding friction, depending in particular on the vibration frequency to be damped and / or the force acting on the device according to the invention.

[0020] The device can be comprised of a power line mast, a support mast of a high-voltage circuit breaker, and / or a support mast of an instrument transformer. Damping vibrations and / or kinetic energy in the mast enables reliable operation of the high-voltage equipment without the risk of failures, particularly due to mast breakage, e.g., during storms and / or earthquakes. A method according to the invention for vibration damping in high-voltage equipment, particularly using a previously described device, comprises connecting elements that mechanically and stably fix support elements of a support arrangement of a high-voltage equipment in space and, when mechanical vibrations occur in the high-voltage equipment, dampen the mechanical vibration in a defined manner via a predetermined sliding friction with the support elements and via a spatially predetermined clearance relative to the support elements.

[0021] The connecting elements can dampen a mechanical vibration between supporting elements by means of intermediate elements arranged between the supporting elements and / or between supporting elements and connecting elements, with a specific coefficient of sliding friction between the supporting element and the intermediate element, particularly in the range of 0.01 to 0.3 and / or in the range greater than 1, particularly by means of a coating of the intermediate elements, and / or by means of a predetermined clearance of the connecting elements to the supporting elements, particularly in the range of micrometers to millimeters.

[0022] The advantages of the inventive method for vibration damping in high-voltage equipment, in particular using a previously described device, according to claim 14, are analogous to the previously described advantages of the inventive device for vibration damping in high-voltage equipment according to claim 1 and vice versa.

[0023] In the following, an embodiment of the invention is schematically described in the Figure 1 and 2 illustrated and described in more detail below.

[0024] The following show Figure 1 schematically shows a high-voltage device 1 with a power cable 2 on an overhead line mast 4, which comprises steel profile lattice bars as support elements 5, and Figure 2 schematically shows a section of a device 3 according to the invention for vibration damping in the high-voltage device 1, with coated washers as intermediate elements 7 for mechanical damping of vibrations in the overhead line mast 4. Figure 1 .

[0025] In Figure 1 A high-voltage device 1 with high-voltage or power cables 2 is shown schematically. The electrical cables or lines 2 are attached to an overhead line mast as a support structure 4, in particular suspended via insulators. In the exemplary embodiment of the Fig. 1The support structure 4 is designed with four arms, each of which carries a cable 2. Support structures 4 can alternatively or additionally carry other high-voltage equipment 1, e.g., transformers, instrument transformers, circuit breakers, disconnectors and / or grounding electrodes.

[0026] The support structure 4 has the form of a steel lattice mast, with steel girders as load-bearing elements 5. The load-bearing elements 5 are, for example, L-, T-, or double-T-shaped, with high mechanical stability. Alternatively or additionally to steel girders, load-bearing elements 5 made of other materials can also be used, e.g., cast iron, wood, plastic, composite materials, and / or carbon fiber. The load-bearing elements 5 are arranged and connected to each other in such a way as to create high mechanical stability for the support structure 4. The load-bearing elements 5 are, for example, arranged to form or enclose triangles, quadrilaterals, in particular parallelograms, and / or pyramid shapes. The support structure 4 is placed on a foundation 8, in particular made of concrete, on the ground.

[0027] The design of the support structure 4 as a steel lattice tower achieves high mechanical strength and stability at a relatively low weight. Depending on the connection of the support elements 5 to one another, e.g., mechanically rigid connections through welding and / or detachable connections such as screws and / or bolts, a high stiffness of the support structure 4 is achieved. However, under external loads on the support structure 4, such as wind / storms and / or earthquakes, this high stiffness can lead to problems, particularly irreversible damage up to and including the breakage of support elements 5, and / or buckling of the support structure 4. This would irreversibly destroy the high-voltage equipment 1 and cause disruptions and outages in the connected electrical power grid. Measures to prevent damage and / or destruction of the support structure 4, such as...Vibration dampers in the foundation are complex, expensive and can often only dampen certain frequencies of mechanical vibrations of the support arrangement 4.

[0028] According to the invention, vibrations of the support arrangement 4 are damped by reducing the stiffness of the support arrangement 4, particularly above a certain threshold of the forces occurring. The reduction in stiffness of the support arrangement 4 is achieved by allowing movement of the support elements 5 relative to one another. This allows vibrations of the support arrangement 4 to be dampened, for example, under environmental influences such as storms and / or earthquakes, and ensures or maintains high mechanical stability of the support arrangement 4. The ability of the support elements 5 to move relative to one another while maintaining high mechanical stability of the support arrangement 4 is achieved by not welding the support elements 5 rigidly together, but rather connecting them to special intermediate elements via connecting elements. These connecting elements are, for example,guided through boreholes in the support elements 5, and in combination with the size of the boreholes and the intermediate elements result in damping elements.

[0029] In Figure 2 The figure schematically shows a section of a device 3 according to the invention for vibration damping in a high-voltage device 1, with a support arrangement 4 according to the Figure 1Connecting elements 6, 6' are guided in openings, in particular bores or boreholes 9, of the support elements 5, and, via coated washers as intermediate elements 7, 7', provide mechanical damping of vibrations of the support arrangement 4. The coated washers as intermediate elements 7, 7' are arranged between the connecting elements 6, 6' and the support elements 5, and between different support elements 5. The coating is selected according to predefined coefficients of sliding friction in order to achieve the desired damping with a defined mechanical stiffness of the support arrangement 4.

[0030] The washers 7 are coated, for example, with layers of low coefficients of sliding friction, particularly in the range of 0.01 to 0.3, to achieve damping at low forces and / or high vibration frequencies. Alternatively or additionally, the washers 7' are coated, for example, with layers of high coefficients of sliding friction, particularly in the range greater than 1, to achieve damping at high forces and / or low vibration frequencies. As in Figure 2 As shown, stacks of identical and / or different washers 7 can be arranged as intermediate elements between the connecting elements 6, 6' and the support elements 5, and between different support elements 5. This enables damping over a wide range of forces and vibration frequencies, especially low and high vibration frequencies.

[0031] In Figure 2Figure 3, which shows a section of a vibration damping device 3 according to the invention, illustrates two L-shaped support elements 5 of a support arrangement 4, in particular a power line mast, mechanically connected to each other by means of connecting elements, in particular a screw 6 and a nut 6'. A stack of a washer 7 as an intermediate element with a layer having a low coefficient of sliding friction and a washer 7' as an intermediate element with a layer having a high coefficient of sliding friction are arranged between the two L-shaped support elements 5 and between a support element 5 and the screw 6, as well as between a support element 5 and the nut 6'. This forms a damping element which dampens vibrations of the support arrangement 4 over a wide frequency and / or force range. Below a threshold value of the different and / or oppositely directed forces on the support elements 5, i.e.,Below a threshold value of the difference of forces on the two support elements 5, static friction leads to a stable, stiff, spatially fixed support arrangement 4 with support elements 5 which do not change their position relative to each other.

[0032] For example, in the case of wind and / or earthquakes, forces greater than the threshold value act on the support elements 5, and the washers 7, 7' begin to slide through the coating in a predefined manner, i.e., sliding friction takes effect. This dampens the vibration at predetermined forces and / or frequencies; that is, the kinetic energy transferred to the support elements 5 by, for example, wind and / or an earthquake is converted into heat energy via sliding friction. The movement and / or vibration of the support elements 5 relative to each other, and thus of the support assembly 4 as a whole, is damped.

[0033] The embodiments described above can be combined with one another and / or with the prior art. For example, support assemblies 4 can carry other elements 2 of the high-voltage equipment 1 instead of cables or conductors 2, in particular transformers, circuit breakers, disconnectors, and / or instrument transformers. The support assemblies 4 can have no arms, one arm, two arms, or more arms and, for example, a triangular or quadrilateral, in particular a square, cross-section. The support assemblies 4 can have the form of a lattice tower or a grid tower, or comprise only individual support elements 5. Support elements 5 can be, for example, flat like a ribbon, L-shaped, T-shaped, and / or double-T-shaped, and can be made of, for example, steel, iron, wood, plastics, composite materials, ceramics, and / or carbon, or comprise these materials. The connecting elements 6 can comprise screws 6 and nuts 6', and / or, for example,The support elements 5 comprise bolts, wherein at least one intermediate element 7, 7', particularly in the form of a coated washer, is arranged between each bolt 6 and support element 5. The support elements 5 are connected to one another via connecting elements 6, wherein connecting elements 6 are, for example, guided through the support elements 5 in boreholes 9. The size of the boreholes 9, as through openings in the support elements 5, determines, among other things, the degrees of freedom with respect to the movement of the connecting elements 6 of the device 3 for vibration damping, and thus, among other things, the damping rate and the damping amplitude, and the maximum movement of the support elements 5 relative to each other.

[0034] Stacks of intermediate elements 7 can comprise identical and / or two or more different intermediate elements 7, in particular washers with different coatings. Individual intermediate elements 7 can have different coatings on different sides, or they can be stacked in layers of different materials. The intermediate elements 7 and / or stacks of intermediate elements 7, 7' can, for example, be arranged only between support elements 5, or only between connecting elements 6, 6' and support element 5, or only between connecting elements 6, 6'. Reference symbol list

[0035] 1 High-voltage equipment 2 Element of the high-voltage equipment, in particular cable 3 Vibration damping device 4 Support arrangement, e.g., overhead line mast 5 Support element, e.g., steel beam 6 Connecting element (screw 6, nut 6') 7 Intermediate element (coated washer 7 for low friction and coated washer for increased friction 7') 8 Foundation 9 Opening in the support element, e.g., through hole

Claims

1. Apparatus (3) for damping vibrations in high-voltage devices (1), having a carrier arrangement (4) for elements (2) of the high-voltage device (1), said arrangement comprising support elements (5) which are connected to one another via connecting elements (6, 6'), wherein intermediate elements (7, 7'), which are configured to damp vibrations, are arranged between the connecting elements (6, 6') and the support elements (5) and / or between different support elements (5), wherein the intermediate elements (7) are coated washers, characterized in that in each case a stack of different intermediate elements (7, 7'), an intermediate element (7) with a coating for lower friction and an intermediate element (7') with higher friction, in conjunction with at least one support element (5) and with at least one connecting element (6, 6'), forms a damping element for mechanical vibrations, with a stack of different intermediate elements (7, 7') between two support elements (5) and / or a stack of different intermediate elements (7, 7') in each case between a respective carrier (5) and a connecting element (6, 6').

2. Apparatus (3) according to Claim 1, characterized in that the intermediate elements (7) are coated with a polymer, in particular Teflon, PTFE and / or PCTFE, a metal, in particular silver, and / or graphite.

3. Apparatus (3) according to either of Claims 1 and 2, characterized in that the coating of the intermediate elements (7) has a determined coefficient of sliding friction on the material of the support elements (5), in particular in the range of 0.01 to 0.3 and / or in the range of greater than 1.

4. Apparatus (3) according to Claim 1, characterized in that the intermediate elements (7') are washers composed of an elastic material, in particular plastic and / or rubber.

5. Apparatus (3) according to one of the preceding claims, characterized in that the carrier arrangement (4) is a lattice mast, in particular a steel framework mast and / or T-shaped mast.

6. Apparatus (3) according to one of the preceding claims, characterized in that the support elements (5) are T beams or double-T beams, in particular composed of steel.

7. Apparatus (3) according to one of the preceding claims, characterized in that the connecting elements (6, 6') are screws (6) with nuts (6') and / or bolts, in particular composed of steel.

8. Apparatus (3) according to Claim 7, characterized in that the connecting elements (6, 6') are configured to connect the support elements (5) via openings (9) in the support elements (5), in particular via continuous bores.

9. Apparatus (3) according to Claim 8, characterized in that the openings (9) are designed in such a way that the connecting elements (6, 6') are mounted in the support elements (5) in a movable manner, in particular with a degree of freedom with respect to movement in dependence on a vibration to be damped and / or a determined earthquake level.

10. Apparatus (3) according to Claim 8, characterized in that the connecting elements (6, 6') have play in the range of micrometres or up to millimetres in the openings (9).

11. Apparatus (3) according to one of the preceding claims, characterized in that in each case at least one intermediate element (7, 7'), in particular two different intermediate elements (7, 7'), in conjunction with at least one support element (5), in particular with two support elements (5), and with at least one connecting element (6, 6'), in particular at least two different connecting elements (6, 6'), forms / form a damping element for mechanical vibrations.

12. Apparatus (3) according to one of the preceding claims, characterized in that in each case a stack of different intermediate elements (7, 7') in conjunction with two support elements (5) and with at least one connecting element (6, 6') forms a damping element for mechanical vibrations.

13. Apparatus (3) according to one of the preceding claims, characterized in that the apparatus (3) is comprised by a power transmission mast, a support mast of a high-voltage circuit breaker and / or a support mast of an instrument transformer.

14. Method for damping vibrations in high-voltage devices, using an apparatus (3) according to one of the preceding claims, characterized in that connecting elements (6, 6') spatially fix support elements (5) of a carrier arrangement (4) of a high-voltage device (1) in a mechanically stable manner, and when mechanical vibrations occur on the high-voltage device (1), the connecting elements (6, 6') damp the mechanical vibration in a defined manner by means of a predetermined sliding friction with the support elements (5), and also by means of spatially predetermined play with respect to the support elements (5).

15. Method according to Claim 14, characterized in that the connecting elements (6, 6') damp a mechanical vibration between support elements (5) by way of intermediate elements (7, 7') which are arranged between the support elements (5) and / or between support elements (5) and connecting elements (6, 6') and which have a determined coefficient of sliding friction between support element (5) and intermediate element (7, 7'), in particular in the range of 0.01 to 0.3 and / or in the range of greater than 1, in particular by means of a coating of the intermediate elements (7, 7'), and / or by way of predetermined play between the connecting elements (6, 6') and the support elements (5), in particular in the range of micrometres up to millimetres.