Dead-tank high-voltage circuit breaker

Abstract

The invention relates to a dead-tank high-voltage circuit breaker (1) comprising at least one first interrupter (2) and at least one control element (4), the at least one control element (4) including a varistor (5). The dead-tank high-voltage circuit breaker (1) also comprises 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.

Description

[0001] Description

[0002] Dead-tank high-voltage circuit breaker

[0003] The invention relates to a dead-tank high-voltage circuit breaker, with at least one first switching path and with at least one control element, wherein the at least one control element comprises a varistor.

[0004] A dead-tank high-voltage circuit breaker with a switching gap and an arrester connected in parallel to the switching gap is known, for example, from US 2015 / 0364285 Al.

[0005] A dead-tank 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 arranged, for example, in a metal housing, in particular designed as a tank and earthed, i.e., designed as a dead tank. The housing is, for example, cylindrical and sealed gas-tight. Elements of a kinematic chain are movably mounted in the housing, e.g., a drive rod and / or gear elements, which are mechanically connected to a drive on or in the housing. The drive is, for example, arranged or attached to the outside of the dead-tank housing and comprises, for example,a gear mechanism which, via an operating rod and, for example, a gear mechanism inside the dead tank housing, mechanically drives the switching paths simultaneously or at different times. A drive mechanism can be, for example, a motor and / or a spring-loaded mechanism. This allows the switching paths to be opened and / or closed, i.e. switched on and / or off. The dead tank housing is, for example, filled 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, B .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 a dead-tank high-voltage circuit breaker with higher reliability, longevity and reduced susceptibility to faults, in which distortion of the voltage distribution between switching paths or overloading of the switching paths is reduced or avoided.

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

[0009] A dead-tank high-voltage circuit breaker according to the invention comprises at least one first switching path and at least one control element, wherein the at least one control element comprises a varistor. Furthermore, the dead-tank high-voltage circuit breaker comprises 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.

[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] A number of switching paths connected in series, in particular arranged with their respective longitudinal axes on a longitudinal axis, enable high voltages to be switched in a compact design. Varistors as control elements on switching paths connected in series enable distortion-free voltage distribution between the switching paths or at least a reduction in the distortion, as a result of which overloading of the switching paths can be avoided or at least reduced. This enables a dead-tank high-voltage circuit breaker which is designed to switch high voltages and which has greater reliability, a longer service life and is less susceptible to faults. In particular with vacuum interrupters connected in series, 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. Distortions in the voltage distribution without varistors can occur, for example, due to residual currents in the vacuum interrupters, which can cause the control capacitors to be charged or discharged. Varistors compensate for such residual currents or charging and / or discharging, as recent experiments have shown. 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, such as at least one varistor, is connected in parallel 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 previously described advantages for the dead tank 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 dead-tank 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 dead-tank high-voltage circuit breakers, particularly for reliably switching the switch on or off at high voltages, i.e., for closing or opening the current path via the switching paths.

[0015] The dead-tank high-voltage circuit breaker can be designed to switch 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 can cause damage or even irreversible destruction to dead-tank high-voltage circuit breakers or the switching paths, particularly at voltages greater than or equal to 52 kV. 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 at least one first switching path and the at least one second switching path and the control elements can be arranged in one housing. Such a design of the dead-tank 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. With exactly one housing for the switching paths and control elements, a compact, space-saving, cost-effective design is achieved.

[0019] Alternatively, the at least one first switching path and the at least one second switching path can be arranged in one housing and the control elements can be arranged in at least one further, in particular parallel, housing, in particular each control element in a separate housing or each control element in a separate housing with the exception of the resistors and capacitors of a respective switching path, which can each be arranged together in one housing. This is associated with the advantages for the switching paths described above, with control elements in separate housings from the housing of the switching paths enabling better electrical insulation of the control elements from the switching paths, without the risk of electrical arcing between control elements and switching paths.

[0020] Alternatively, the at least one first switching path and the at least one second switching path can each be arranged in a housing and the control elements can be arranged in at least one further, in particular parallel, housing, in particular each control element in a separate housing or each control element in a separate housing with the exception of the resistors and capacitors of a respective switching path, which can each be arranged together in a housing. A structure with separate housings for the respective switching paths and separate housings for the control elements is less compact, but enables better electrical insulation of the switching paths from one another and of the control elements from the switching paths, without the risk of electrical arcing between control elements and switching paths. This results in greater reliability and a long service life, particularly at high voltages.

[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 a dead tank according to the invention.

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

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

[0026] Figure 3 is a top view of the dead tank high voltage

[0027] Circuit breaker 1 of Figure 2 , and

[0028] Figure 4 is a side view of a second embodiment of a dead-tank high-voltage circuit breaker 1 according to Figure 1 with switching paths and associated control elements as well as varistors, each in a separate housing 10 to 15, and Figure 5 is a plan view of the dead-tank high-voltage circuit breaker 1 of Figure 4.

[0029] Figures 1 to 5 show dead-tank high-voltage circuit breakers 1 according to the invention. Figure 1 shows the principle of a dead-tank high-voltage circuit breaker 1 according to the invention in an oblique plan view in a sectional view. The dead-tank 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 arranged in a common tank as a housing 10, e.g. made of steel, aluminum and / or cast iron. 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.

[0030] The switching paths 2 and 3 are arranged with their longitudinal axes on a common axis, vertical to a longitudinal axis of a support 18. The support 18 and the switching paths 2 and 3 form a T-shape. Other shapes of supports 18 are also possible, e.g. support frames with support elements in the form of support beams, screwed and / or welded and / or with an extension which essentially corresponds to the extension of the housing 10. A drive 9 is arranged on the support 18, for example. The switching paths 2 and 3 are driven during switching via the drive 9 and elements of a kinematic chain, such as a gear 17 and at least one switching rod 16, arranged in particular in the housing 10. The switching paths 2 and 3 can be switched simultaneously or at different times, i.e. they can be switched on and / or off or closed and / or interrupted. The dead tank high-voltage circuit breaker 1 is thus designed, e.g. B.To connect or disconnect high-voltage lines, electrical devices such as generators and / or electrical consumers, in particular to an electrical power grid.

[0031] Control elements 4, such as varistors 5, capacitors 7 and / or resistors 6, are arranged and connected in parallel to the switching paths 2 and 3. According to the invention, the control elements comprise varistors 5, wherein in particular at least one varistor 5 is connected in parallel to each switching path 2, 3. Figure 1 shows a schematic diagram of the parallel connection of at least one varistor 5 to a switching path 2, 3, as well as a capacitor 7 and a resistor 6 connected in series and connected in parallel to an associated switching path 2, 3 with a parallel varistor 5. The switching paths 2, 3 are fastened in the housing 10, for example, via holders and can be electrically contacted to the outside via bushings 8 with connections 19. Alternatively or additionally, in a GIS (Gas Insulated Switchgear) version, the housing 10 can be designed as a module and, instead of bushings, further modules can be connected orwhich is not shown in the figures for the sake of simplicity.

[0032] Figure 2 shows a side view of an embodiment of a dead-tank high-voltage circuit breaker 1 according to Figure 1, with switching paths and associated control elements as well as varistors arranged in a common housing 10, which are not shown in Figure 2 for the sake of simplicity. A schematic diagram is shown in section along the vertical longitudinal axis of the support 18. A gear 17 is arranged between the support 18 and the housing 10, in particular the dead-tank housing 10. The support 18 is, for example, a metal frame. A drive rod or switching rod 16 is arranged in the housing 10 as an element of the kinematic chain, which, during switching, transmits the movement from the drive 9, for example via gear elements 17, which are not shown in detail for the sake of simplicity and are arranged, for example, at the beginning and / or end of the switching rod 16, to the first and second switching paths 2, 3.

[0033] The common housing 10 of the switching paths 2, 3 and control elements, in particular varistors, capacitors, and resistors, is arranged on the support 18 with a gear 17 interposed therebetween, in particular a cylindrical tank 10 with a horizontal longitudinal axis for each switching path 2, 3 or a common cylindrical tank with a horizontal longitudinal axis for all switching paths 2, 3, as shown in Figure 3. The shape of the dead-tank high-voltage circuit breaker 1 thus results in a T-shape in the exemplary embodiments shown in the figures. Other shapes of supports 18 are also possible, as described above, e.g., flat or U-shaped supports 18, which are not shown in the figures for simplicity.

[0034] Figure 3 shows a schematic diagram of the dead-tank high-voltage circuit breaker 1 of Figure 2 in a top view as a section, 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, a voltage distribution across the switching paths 2, 3 is achieved via the control elements 4, which, for example, corresponds to an ideal 50:50 distribution if the values ​​of the capacitors and resistors used are the same.

[0035] 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, is established. During the switching operation, in particular during the post-current phase, the post-current from the switching paths 1, 3 causes the voltage ratio specified by the control elements 7 to be distorted. This can lead to an overload of the individual switching paths. The use of surge arresters in the form of varistors 5 parallel to the switching path 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.

[0036] Figure 4 shows a side view of an exemplary embodiment of a dead-tank 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 basic diagram in a sectional view, analogous to Figure 2, along the vertical longitudinal axis of the support 18. A gear 17 is arranged between the support 18 and the housing 10, in particular the dead-tank housing 10. The support 18 is, for example, a metal frame. Arranged in the housing 10 is a drive rod or switching rod 16 as an element of the kinematic chain, which, when switching, transmits the movement from the drive 9, for example via gear elements 17, which are not shown in detail for the sake of simplicity and, for example, are arranged at the beginning and / or end of the switching rod 16, to the first and second switching path 2, 3.

[0037] The housing 10, 11 of the switching paths 2, 3 is arranged on the carrier 18, with the gear 17 arranged therebetween in the exemplary embodiment in Figure 4, the housing 11 of the switching path 3 being shown in plan view in Figure 5 and being covered by the housing 10 of the switching path 2 in Figure 4. The housings 12, 13 of the varistors 5 are also arranged on the carrier 18, in particular fastened to the housings 10, 11, 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 in plan view in Figure 5 and being covered in Figure 4 by the housing 12 of the varistor 5 of the first switching path 2.In addition, arranged on the carrier 18, in particular fastened to the housings 10, 11, are the housings 14, 15 of the resistors 6 and / or capacitors 7, 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 as a top view in Figure 5, and is covered in Figure 4 by the housing 14 of the resistors 6 and / or capacitors 7 of the first switching path 2.

[0038] The housings 10 to 15 are e.g. designed as cylindrical tanks, in particular made of metal, or the housings 10 and 11 are designed as cylindrical tanks, in particular made of metal, and the housings 12 to 15 are designed as cylindrical hollow insulators with a horizontal longitudinal axis.

[0039] The housings 10 and 11, and / or 12 and 13, and / or 14 and 15 can also be designed as one housing, as shown in Figure 3. The shape of the dead-tank high-voltage circuit breaker 1 results in a T-shape in the exemplary embodiments of Figures 1 to 5. Other shapes, e.g., an inverted L or gallows shape or previously described shapes, are also possible.

[0040] Figure 5 shows a schematic diagram of the dead-tank high-voltage circuit breaker 1 of Figure 4 in plan view, with the interconnection of the switching paths 2, 3 and control elements 4. In the exemplary embodiment of 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, a voltage distribution across the switching paths 2, 3 takes place via the control elements 4, which, for example, corresponds to an essentially ideal 50:50 distribution when 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 or 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.

[0041] 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.

[0042] The dead-tank high-voltage circuit breaker 1 is designed, for example, to switch voltages of up to 52 kV and higher. The housings 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 dead-tank high-voltage circuit breaker 1 can have a T-shape, or other shapes such as a gallows shape or other shapes, in particular those described above and / or shapes which are known from the prior art. The support 18 can also be designed in several parts, e.g. a support part at each end of a tank 10. In this case, two or more switching paths with associated control elements can be provided in the dead-tank 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 can be combined in groups in housings, e.g.The resistors and capacitors of a switching path and / or the varistors of a switching path are housed in one housing. Other shapes and distributions into housings are also possible. Resistors 6 and / or capacitors 7 can be connected in series, and / or resistors 6 and / or capacitors 7 can be connected in parallel. Other interconnections, particularly with other electrical elements, are also possible.

[0043] Reference symbol list

[0044] 1 dead-tank 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 Feedthrough with electrical connection

[0052] 9 Drive

[0053] 10 Dead tank housing or 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. Dead-tank high-voltage circuit breaker (1) , with at least one first switching path (2) and with at least one control element (4), wherein the at least one control element (4) comprises a varistor (5), characterized in that at least one second switching path (3) is included, wherein the at least one first switching path (1) and the at least one second switching path (3) are connected in series.

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

6. Dead-tank 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. Dead-tank 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. Dead-tank high-voltage circuit breaker (1) according to one of the preceding claims, characterized in that a housing (10) is included, in which the at least one first and the at least one second switching path (2, 3) are arranged.

9. Dead-tank 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) and the control elements (4) are arranged in a housing (10).

10. Dead-tank high-voltage circuit breaker (1) according to one of claims 1 to 8, characterized in that the at least one first switching path (2) and the at least one second switching path (3) are arranged in a housing (10) and the control elements (4) are arranged in at least one further, in particular parallel, housing, in particular each control element (4) in a separate housing or each control element (4) in a separate housing (12, 13, 14, 15) with the exception of the resistors (6) and capacitors (7) of a respective switching path (2, 3), which are each arranged together in a housing (14, 15).

11. Dead-tank high-voltage circuit breaker (1) according to one of claims 1 to 8, characterized in that the at least one first switching path (2) and the at least one second switching path (3) are each arranged in a housing (10, 11) are arranged and the control elements (4) are arranged in at least one further, in particular parallel, housing, in particular each control element (4) in a separate housing or each control element (4) in a separate housing (12, 13, 14, 15) with the exception of the resistors (6) and capacitors (7) of a respective switching path (2, 3), which are each arranged together in a housing (14, 15).

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