High-voltage outdoor circuit breaker

Abstract

The invention relates to a high-voltage outdoor circuit breaker (1) comprising at least one first interrupter (2) and at least one second interrupter (3), the at least one first interrupter (1) and the at least one second interrupter (3) being connected in series. The high-voltage outdoor circuit breaker (1) also comprises control elements (4) that include at least one varistor (5).

Description

[0001] Description

[0002] Free-air high-voltage circuit breaker

[0003] The invention relates to an outdoor high-voltage circuit breaker having at least one first switching path and at least one second switching path, wherein the at least one first switching path and the at least one second switching path are connected in series. The outdoor high-voltage circuit breaker further comprises control elements.

[0004] Such an outdoor high-voltage circuit breaker is known, for example, from DE 10 2016 202 764 Al.

[0005] An outdoor high-voltage circuit breaker is designed, for example, to switch voltages in the range of up to 1200 kV and currents in the range of up to several thousand amperes. In order to switch high voltages and / or currents, at least two switching paths are connected in series. A switching path comprises, for example, at least one vacuum interrupter and / or at least one interrupter unit with a rated current and arcing contact. The switching paths are, for example, each arranged in an insulator housing, in particular made of ceramic, silicone and / or a composite material. The housings of the switching paths are, for example, arranged one behind the other on a column-shaped hollow insulator, in particular a T-shape. Elements of a kinematic chain are movably mounted in the hollow insulator, e.g. a drive rod and / or gear elements that are mechanically connected to a drive. The drive is, for example,arranged or fastened at the base of the hollow insulator and, for example, mechanically connected to a gear at the head of the hollow insulator via a drive rod in order to mechanically drive the switching paths simultaneously or at different times via the gear. This means that the switching paths can be opened and / or closed, i.e. switched on and / or off. The housings are filled, for example, with insulating gas, in particular SF6, CO2, and / or clean air, i.e. purified and dried air. In order to avoid overloading the individual switching paths or vacuum interrupters and / or interrupter units with rated current and arcing contact at high voltages, the voltage must be distributed between the individual switching paths. For example, with two switching paths connected in series, a voltage distribution of 50% to 50% of the voltage between the two switching paths is good. To distribute the voltage between the switching paths, for example:Control elements such as resistors and / or capacitors are used, which are connected in parallel to the switching paths.

[0006] After a power interruption, a steady-state voltage ratio corresponding to the capacitance of the control capacitors is established when the switching paths are open, i.e., when the contacts of the vacuum interrupters and / or interrupter units with rated current and arcing contacts are open. During the switching operation, particularly during the post-current phase, the post-current from the switching path distorts the voltage ratio specified by the control capacitors. This distortion can lead to overloading of the individual switching paths. In extreme cases, this can result in irreversible destruction of the high-voltage circuit breaker.

[0007] The invention is based on the object of specifying an outdoor high-voltage circuit breaker with higher reliability, longevity and reduced susceptibility to faults, in which distortion of the voltage distribution between the switching paths or overloading of the switching paths is reduced or avoided.

[0008] This object is achieved according to the invention by an outdoor high-voltage circuit breaker according to claim 1. Advantageous embodiments of the outdoor high-voltage circuit breaker according to the invention are specified in the subclaims.

[0009] An outdoor high-voltage circuit breaker according to the invention comprises at least one first switching path and at least one second switching path, wherein the at least one first switching path and the at least one second switching path are connected in series. Furthermore, the outdoor high-voltage circuit breaker comprises control elements. The control elements comprise at least one varistor.

[0010] A varistor is an electrical component or part whose electrical resistance depends on the applied electrical voltage. Above a certain threshold voltage, which is specific to the respective varistor, the differential resistance decreases abruptly. The polarity of the current and voltage has no influence, i.e., there is no rectifying effect like with a diode. A varistor is therefore a voltage-dependent resistor, also known as a VDR or variable resistor. An example of a varistor is a metal oxide varistor.

[0011] Varistors as control elements on series-connected switching paths enable distortion-free voltage distribution between the switching paths or at least a reduction in the distortion, which means that overloading of the switching paths can be avoided or at least reduced. This makes it possible to have an outdoor high-voltage circuit breaker with greater reliability, a longer service life and a reduced susceptibility to faults. In particular with series-connected vacuum interrupters, distortion of the voltage distribution can be avoided or reduced by using varistors connected in parallel to the vacuum interrupters, e.g. in addition to parallel-connected control elements such as capacitors and / or resistors. Distortion of the voltage distribution without varistors can occur, for example, due to wake currents in the vacuum interrupters, which can cause the control capacitors to charge or discharge. Varistors compensate for such wake currents.Charging and / or discharging, as recent experiments have demonstrated. Thus, the previously described advantages of varistors can be achieved.

[0012] Control elements can be connected in parallel to at least one switching path, in particular in parallel to each switching path. If at least one control element is connected in parallel, such as at least one varistor to each switching path, in particular all of the tail currents can be compensated for by the varistors. With advantageous wiring or interconnection of switching paths, it may also be sufficient to connect only one or more switching paths with parallel control elements, without connecting all of the switching paths with parallel control elements, in particular ensuring sufficient compensation of tail currents. This is possible in particular with unequal switching paths. This results in the advantages described above for the outdoor high-voltage circuit breaker which comprises the switching paths.

[0013] Electrical resistors and / or capacitors can be included as control elements. Resistors and capacitors are well-suited as electrical control elements for controlling voltages at switching gaps, particularly vacuum interrupters, in outdoor high-voltage circuit breakers.

[0014] The at least one first and / or the at least one second switching path can comprise at least one vacuum interrupter and / or at least one interrupter unit with rated current and arcing contacts. Vacuum interrupters and interrupter units with rated current and arcing contacts are well suited as switching paths in outdoor high-voltage circuit breakers, particularly for reliably switching the breaker on or off at high voltages, i.e., for closing or opening the current path via the switching paths.

[0015] The outdoor high-voltage circuit breaker can be designed for switching voltages greater than and / or equal to 52 kV. Uneven voltage distributions across the switching paths, particularly due to residual currents, lead to greater problems at higher voltages than at lower voltages and, particularly at voltages greater than or equal to 52 kV, can cause damage or even irreversible destruction to outdoor high-voltage circuit breakers or the switching paths. The use of varistors as control elements is particularly advantageous at high voltages, e.g., equal to or greater than 52 kV, with the advantages described above.

[0016] At least one varistor can be connected in parallel to each switching path. Particularly at high voltages and / or currents, individual varistors may not be sufficient to adequately or completely compensate for, for example, residual currents or to ensure uniform voltage distribution. To achieve the advantages described above to a sufficient extent, at least one varistor can be connected in parallel to each switching path, or this may be necessary.

[0017] At least one varistor can be connected in parallel to each switching path, and at least one resistor and / or at least one capacitor can be connected in parallel to the respective switching path and to the at least one varistor connected in parallel. With the appropriate circuit, a good circuit can be created that enables uniform voltage distribution across the switching paths and / or enables good post-current compensation, with the advantages described above.

[0018] The outdoor high-voltage circuit breaker can be T-shaped, in particular with the at least one first switching path in one leg of the T-shape and with the at least one second switching path in the opposite leg of the T-shape. In this context, the legs of the T-shape refer to the right and left horizontal sides of the T. Such a design of the outdoor high-voltage circuit breaker enables a simple series connection of several switching paths, compactly, in particular with a parallel arrangement of control elements, such as varistors, in particular parallel to each switching path, with a cost-effective design, electrically insulated from the ground or soil.

[0019] The at least one first switching path can be arranged in a first housing, and the at least one second switching path can be arranged in a second housing, in particular in an insulator housing with ribs, wherein the respective control elements of the switching paths are arranged in the respective housing of the associated switching path. This results in a compact, cost-effective design of the outdoor high-voltage circuit breaker.

[0020] Alternatively, the at least one first switching path can be arranged in a first housing and the at least one second switching path can be arranged in a second housing, in particular in an insulator housing with ribs, wherein the respective control elements of the switching paths can be arranged in particular in parallel housings, in particular in insulator housings with ribs arranged parallel to the housings of the switching paths.The at least one first switching path can be arranged in a first housing, and the associated varistor can be arranged in a housing that is in particular parallel and / or at least one resistor and / or at least one capacitor can be arranged as control elements in a further housing that is in particular parallel, and the at least one second switching path can be arranged in a housing, in particular with a common longitudinal axis of the housings of the first and second switching path, and the associated varistor can be arranged in a housing that is in particular parallel to the housing of the second switching path and / or at least one resistor and / or at least one capacitor can be arranged as control elements in a further housing that is in particular parallel to the housing of the second switching path and / or the varistor.The use of separate housings for switching paths and control elements and / or for control elements among each other may be necessary, particularly at high voltages, and / or may have advantages in terms of better dielectric strength against electrical arcing between elements of the switch.

[0021] In the following, embodiments of the invention are shown schematically in the figures and described in more detail below.

[0022] The

[0023] Figure 1 shows the principle of an inventive outdoor

[0024] High-voltage circuit breaker 1 in an oblique view, and the

[0025] Figure 2 is a side view of an embodiment of an outdoor high-voltage circuit breaker 1 according to Figure 1, with switching paths 2, 3 and associated control elements 4 as well as varistors 5 in a common housing 10, and

[0026] Figure 3 shows a plan view of the outdoor high-voltage

[0027] Circuit breaker 1 of Figure 2 , and

[0028] Figure 4 is a side view of a second embodiment of an outdoor high-voltage circuit breaker 1 according to Figure 1 with switching paths 2, 3 and associated control elements 4 as well as varistors 5 each in their own housings 10 to 15, and

[0029] Figure 5 shows a plan view of the outdoor high-voltage

[0030] Circuit breaker 1 of Figure 4.

[0031] Figures 1 to 5 show outdoor high-voltage circuit breakers 1 according to the invention. Figure 1 shows the principle of an outdoor high-voltage circuit breaker 1 according to the invention in an oblique view. The outdoor high-voltage circuit breaker 1 comprises a first and a second switching path 2 and 3, which are connected in series. The switching paths 2 and 3 are each arranged in ribbed insulators 10, 11, 14, 15, e.g. made of ceramic, silicone and / or composite material, which are visible in Figure 1 and cover or encompass the switching paths 2, 3 in Figure 1. The switching paths 2 and 3 are, for example, vacuum interrupters and / or interrupter units with rated current and arcing contacts, and are spatially enclosed, for example, by a switching gas, e.g. SF6, CO2 and / or clean air, i.e. purified, dried air.

[0032] The insulators 10, 11 of the switching paths 2 and 3 are arranged with their longitudinal axes on a common axis, vertical to a longitudinal axis of a support insulator 8. The support insulator 8 and the insulators 10, 11 of the switching paths 2 and 3 form a T-shape. At the base of the support insulator 8, for example, a drive 9 is arranged. The switching paths 2 and 3 are driven during switching via the drive 9 and elements of a kinematic chain, in particular arranged in the insulators 8, 10, 11. The switching paths 2 and 3 can be switched simultaneously or at different times, i.e., switched on and / or off, or closed and / or interrupted. The outdoor high-voltage circuit breaker 1 is thus designed to switch, for example, high-voltage lines, electrical devices such as generators and / or electrical consumers, in particular to an electrical power grid, on or off.The power generators and / or consumers as well as electrical lines are connected to the outdoor high-voltage circuit breaker 1 via electrical connections 19.

[0033] Control elements 4, such as varistors 5, capacitors and / or resistors, are arranged and connected in parallel to the switching paths 2 and 3. According to the invention, the control elements comprise varistors 5, with at least one varistor 5 being connected in parallel to each switching path 2, 3 in particular. Figure 1 shows a schematic diagram of the parallel connection of at least one varistor 5 to a switching path 2, 3, with the varistors 5 being able to have their own insulator housing, be arranged in the insulator housing 14, 15 of the other control elements 4, in particular capacitors and / or resistors connected in series and each connected in parallel to a switching path 2, 3, or be arranged in the housing 10, 11 of the respective switching path 2, 3. All switching paths 2, 3 can also be arranged in a common housing, as shown in Figure 2.

[0034] Figure 2 shows a side view of an embodiment of an outdoor high-voltage circuit breaker 1 according to Figure 1, with switching paths 2, 3 and associated control elements 4 as well as varistors 5 arranged in a common housing 10. This shows a schematic diagram in a sectional view, along the vertical longitudinal axis of the support insulator 8 and rotated by 90 degrees to Figure 1. The support insulator 8 is arranged on a support 18, e.g. a metal frame. In the support insulator 8, which is in particular hollow cylindrical, a drive rod or switching rod 16 is arranged as an element of the kinematic chain, which, during switching, transmits the movement from the drive 9, e.g. via gear elements 17, which are not shown in detail for the sake of simplicity and are arranged, e.g., at the beginning and / or end of the switching rod 16, to the first and second switching paths 2, 3.

[0035] The common housing 10 of the switching paths 2, 3 and control elements 4, in particular varistors 5, capacitors 7, and resistors 6, is arranged on the support insulator 8, in particular a cylindrical hollow insulator with a horizontal longitudinal axis for each switching path 2, 3 or a common cylindrical hollow insulator 10 with a horizontal longitudinal axis for all switching paths 2, 3, the latter as shown in Figures 2 and 3. The shape of the outdoor high-voltage circuit breaker 1 thus results in a T-shape.

[0036] Figure 3 shows a schematic diagram of the outdoor high-voltage circuit breaker 1 in Figure 2 in plan view, with the interconnection of the switching paths 2, 3 and control elements 4. In the exemplary embodiment in Figure 3, a first and a second switching path 2, 3 are connected in series, with a varistor 5 connected in parallel to each switching path 2, 3, and with a series-connected capacitor 7 and electrical resistor 6 connected in parallel to each switching path 2, 3. Other numbers of switching paths 2, 3 and control elements 4, in particular without capacitors and / or resistors, and interconnections are also possible. In the interconnection shown in Figure 3, the control elements 4 distribute the voltage across the switching paths 2, 3, which, for example, corresponds to an ideal 50:50 distribution if the values ​​of the capacitors 7 and resistors 6 used are the same.

[0037] After a current interruption, when the contacts of the switching paths 2, 3, in particular the vacuum interrupters and / or interrupter units with rated current and arcing contacts, are open, a steady-state voltage ratio corresponding to the control elements 4, in particular the capacitance of the control capacitors 7. During the switching operation, in particular during the post-current phase, the post-current from the switching paths 2, 3 causes the voltage ratio specified by the control elements 4 to be distorted. This can lead to an overload of the individual switching paths 2, 3. The use of surge arresters in the form of varistors 5 parallel to the switching path 2, 3 prevents this overload. Distortions in the voltage distribution caused by the post-currents in the switching paths 2, 3 and any charging or discharging of the control capacitors 7 caused by these are compensated for.

[0038] Figure 4 shows a side view of an exemplary embodiment of an outdoor high-voltage circuit breaker 1 according to Figure 1, with switching paths 2, 3 and associated control elements 4 as well as varistors 5, each arranged in a separate housing 10 to 15. This shows a schematic diagram in a sectional view, analogous to Figure 2, along the vertical longitudinal axis of the support insulator 8. The support insulator 8 is arranged on the support 18, e.g. a metal frame. In the particularly hollow cylindrical support insulator 8, the drive rod or switching rod 16 is arranged as an element of the kinematic chain, which transmits the movement from the drive 9 during switching, e.g. via gear elements 17, which are not shown in detail for the sake of simplicity and e.g. are arranged at the beginning and / or end of the switching rod 16, to the first and second switching path 2, 3.

[0039] The housings 10, 11 of the switching paths 2, 3 are arranged on the support insulator 8, the housing 11 of the switching path 3 being shown as a plan view in Figure 5 and being covered by the housing 10 in Figure 4. The housings 12, 13 of the varistors 5 are also arranged on the support insulator 8, in particular with the longitudinal axes parallel to the switching path housings 10, 11, the housing 13 of the varistor 5 of the second switching path 3 being shown as a plan view in Figure 5 and being covered by the housing 12 in Figure 5. In addition, arranged on the support insulator 8, the housings 14, 15 of the resistors 6 and / or capacitors 7 are arranged, in particular with the longitudinal axes parallel to the switching path housings 10, 11 and / or varistor housings 12, 13, wherein the housing 15 of the resistors 6 and / or capacitors 7 of the second switching path 3 is shown in Figure 5 as a plan view and is covered by the housing 14 in Figure 4.

[0040] The housings 10 to 15 are designed, for example, as cylindrical hollow insulators with a horizontal longitudinal axis. The housings 10 and 11, and / or 12 and 13, and / or 14 and 15 can also be designed as one housing. On the outer circumference, as shown in Figure 1, the housings 10 to 15 have, for example, ribs to extend the leakage current path. Alternatively, the housings can also be designed, for example, to be smooth. The shape of the outdoor high-voltage circuit breaker 1 results in a T-shape in the embodiments of Figures 1 to 5. Other shapes, e.g., an inverted L, are also possible.

[0041] Figure 5 shows a schematic diagram of the outdoor high-voltage circuit breaker 1 in Figure 4 in plan view, with the interconnection of the switching paths 2, 3 and control elements 4. In the exemplary embodiment in Figure 5, a first and a second switching path 2, 3 are connected in series, with a varistor 5 connected in parallel to each switching path 2, 3, and with a series-connected capacitor 7 and electrical resistor 6 connected in parallel to each switching path 2, 3. Other numbers of switching paths 2, 3 and control elements 4, in particular without capacitors and / or resistors, and interconnections are also possible. In the interconnection shown in Figure 5, the control elements 4 distribute the voltage across the switching paths 2, 3, which, for example, corresponds to an ideal 50:50 distribution if the values ​​of the capacitors 7 and resistors 6 used are the same.The function and advantages are analogous to the function and advantages of the embodiment of Figures 2 and 3. The difference between the embodiment of Figures 2 and 3 and the embodiment of Figures 4 and 5 lies in the arrangement of all electrical elements, in particular switching paths 1 and 2, varistors 5, resistors 6 and / or capacitors 7, in the first case in a housing 10 or in the second case in different housings 10 to 15.

[0042] The previously described embodiments can be combined with one another and / or with the prior art. For example, housings 8, 10, 11, 12, 13, 14, 15 can have a hollow cylindrical shape or other shapes, such as rectangular, particularly hollow shapes. Ribs are arranged on the outer circumference, for example, to extend leakage current paths. Alternatively, the housings can be formed smoothly along the outer circumference. The housings 8, 10, 11, 12, 13, 14, 15 are made of ceramic, silicone, and / or composite materials, for example. However, other materials can also be used.

[0043] The outdoor high-voltage circuit breaker 1 is designed, for example, for switching voltages of up to 52 kV and higher. The housings 8, 10 to 15 can be filled with insulating gas and / or switching gas, i.e., the switching paths 1, 2 and control elements 4 can be spatially enclosed by insulating gas or switching gas. The outdoor high-voltage circuit breaker 1 can have a T-shape or other shapes, such as a gallows shape. Two or more switching paths with associated control elements can be provided in the outdoor high-voltage circuit breaker 1. The control elements 4 can be arranged in the housing of the switching paths and / or have their own housings, or be grouped together in housings, e.g., the resistors and capacitors of a switching path and / or the varistors of a switching path in one housing. Other shapes and divisions into housings are also possible. List of reference symbols

[0044] 1 Free-air high-voltage circuit breaker

[0045] 2 first switching path

[0046] 3 second switching path

[0047] 4 controls

[0048] 5 Varistor

[0049] 6 electrical resistance

[0050] 7 Capacitor

[0051] 8 Support insulator

[0052] 9 Drive

[0053] 10 Housing of the first switching path

[0054] 11 Housing of the second switching path

[0055] 12 Housing of control elements (varistors) of the first switching path

[0056] 13 Housing of control elements (varistors) of the second switching path

[0057] 14 Housing of control elements (resistors and capacitors) of the first switching path

[0058] 15 Housing of control elements (resistors and capacitors) of the second switching path

[0059] 16 Shift rod

[0060] 17 gearboxes

[0061] 18 carriers

[0062] 19 electrical connection

Claims

Patent claims 1. Outdoor high-voltage circuit breaker (1), with at least one first switching path (2) and with at least one second switching path (3), wherein the at least one first switching path (1) and the at least one second switching path (3) are connected in series, and with control elements (4) , characterized in that the control elements (4) comprise at least one varistor (5).

2. Outdoor high-voltage circuit breaker (1) according to claim 1, characterized in that control elements (4) are connected in parallel to at least one switching path (2, 3), in particular in parallel to each switching path (2, 3).

3. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that electrical resistors (6) and / or capacitors (7) are included as control elements (4).

4. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the at least one first and / or the at least one second switching path (2, 3) comprises or is at least one vacuum interrupter and / or at least one interrupter unit with rated current and arcing contact.

5. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the outdoor high-voltage circuit breaker (1) is designed to switch voltages greater than and / or equal to 52 kV.

6. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that at least one varistor is connected in parallel to each switching path (2, 3) (5) is switched on.

7. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that at least one varistor (5) is connected in parallel to each switching path (2, 3) and at least one resistor (6) and / or at least one capacitor (7) is connected in parallel to the respective switching path (2, 3) and to the at least one varistor (5) connected in parallel.

8. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the outdoor high-voltage circuit breaker (1) is T-shaped, in particular with the at least one first switching path (2) arranged in one leg of the T-shape and with the at least one second switching path (3) arranged in the opposite leg of the T-shape.

9. Outdoor high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the at least one first switching path (2) and the at least one second switching path (3) are arranged in a common housing (10), in particular in an insulator housing with ribs, wherein the respective control elements (4) of the switching paths (2, 3) are arranged in the same housing (10) of the switching paths (2, 3), or that the at least one first switching path (2) is arranged in a first housing (10) and the at least one second switching path (3) is arranged in a second housing (11), in particular in an insulator housing with ribs, wherein the respective control elements (4) of the switching paths (2, 3) are arranged in the respective housing (10, 11) of the associated switching path (2, 3).

10. Outdoor high-voltage circuit breaker (1) according to one of claims 1 to 8, characterized in that the at least one first switching path (2) is arranged in a first housing (10) and the at least one second switching section (3) is arranged in a second housing (11), in particular in an insulator housing with ribs, wherein the respective control elements (4) of the switching sections (2, 3) are arranged in particular in parallel housings (12, 13), in particular in insulator housings with ribs arranged parallel to the housings (10, 11) of the switching sections (2, 3).

11. Outdoor high-voltage circuit breaker (1) according to claim 10, characterized in that the at least one first switching path (2) is arranged in a first housing (10), and the associated varistor (5) is arranged in a housing (12) which is in particular parallel, and / or at least one resistor (6) and / or at least one capacitor (7) are arranged as control elements (4) in a further housing (14) which is in particular parallel, and the at least one second switching path (3) is arranged in a housing (11), in particular with a common longitudinal axis of the housings (10, 11) of the first and second switching paths (2, 3), and the associated varistor (5) is arranged in a housing (13) which is in particular parallel to the housing (11) of the second switching path (2), and / or at least one resistor (6) and / or at least one capacitor (7) are arranged as control elements (4) in a further housing (15) which is in particular parallel to the housing (11, 13).

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