RC device for switching on / off induced current by using high-voltage vacuum switch

Abstract

The invention relates to a wiring of an electrical apparatus for high-voltage power transmission, in particular a high-voltage switchgear, having an RC device. According to the invention, the vacuum switch equipment can be applied to gt; the invention relates to choking coil switch application in a high voltage range of 72.5 kV.

Description

Technical Field

[0001] The invention relates to wiring of electrical equipment for high-voltage power transmission, in particular high-voltage switchgear, with RC devices. Background Art

[0002] When switching small inductive currents, such as occur in the use of chokes in high-voltage networks (>=72.5 kV), special protective measures are necessary. Switching tasks involve the risk that transient overvoltages may destroy substation components. In this case, the choke itself is particularly at risk. Gas switches and vacuum switching devices are proposed as switching media, for example.

[0003] SF6 circuit breakers are mainly used in high-voltage power networks. In these applications, gas circuit breakers cannot be operated without additional protective measures. These measures are used to reduce the overvoltages that occur during the switching process.

[0004] Until now, the use of choke switches in high-voltage power grids (>=72.5 kV) has been operated with a combination of an electronic control unit (controlling the exact time of switching on or off) and an SF6 circuit breaker with a single-pole drive. This solution is cost-intensive, requires increased effort at startup and carries the risk that the data of the circuit breaker stored in the control unit, such as the intrinsic switching time, changes during operation (over decades). This can change the optimal switching time and adversely affect the function of the arrangement of the single-pole driven circuit breaker and the electronic control unit. Summary of the invention

[0005] The object of the present invention is to provide a solution which allows the use of vacuum switching devices instead of gas switches in the high-voltage range (>=72.5 kV) and also allows the use of multi-pole switching devices for choke switching applications.

[0006] The above-mentioned technical problem is solved by a device for high-voltage electrical energy transmission comprising the features of claim 1 .

[0007] The effects of transient overvoltages can be significantly reduced using an RC filter circuit (a series circuit consisting of a resistor R and a capacitor C). This solution has been used in medium voltage for many years and is therefore prior art. Therefore, the RC filter circuit component can also be used at the medium voltage level.

[0008] By transferring this technology to higher voltage levels (>=72.5 kV), it becomes possible to use vacuum switching devices instead of gas switches for choke switching applications in the high-voltage range.

[0009] In this case, the RC filter circuit element can be realized by connecting existing discrete RC elements (e.g., RC elements in metal-encapsulated housings (“tanks”) with oil insulation), as is currently already used in medium voltage. Alternatively, the RC element can be integrated into existing or newly designed high-voltage components for gas-insulated (GIS) or air-insulated (AIS) applications.

[0010] The RC filter circuit can be advantageously integrated into an existing or newly designed high-voltage component, or an existing high-voltage module can be expanded / supplemented with corresponding components. Advantageously, the RC element does not need to have a separate, open-air housing (e.g., a metal-encapsulated housing with a bushing) by being integrated into the high-voltage component. This results in cost and space advantages. The multi-pole switching device can be controlled by only one driver.

[0011] Advantageous developments of the invention are specified in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be described in detail below as an embodiment to the extent necessary for understanding with the aid of the accompanying drawings. In the accompanying drawings:

[0013] Figure 1 A gas-insulated high-voltage device according to the invention with a single resistor and three electrodes of a capacitor is shown,

[0014] Figure 2A A high voltage cast resin bushing with a single pole of an RC circuit according to the present invention is shown,

[0015] Figure 2B A high voltage cast resin bushing with three poles of an RC circuit according to the present invention is shown,

[0016] Figure 3 The high-voltage bushing according to the invention is shown in two variant embodiments.

[0017] Figure 4A shows a high voltage bushing according to the invention with an RC element integrated in the housing,

[0018] Figure 4B shows an RC element disc arranged concentrically with a conductor according to the present invention,

[0019] Figure 5A A high-voltage power switch according to the invention is shown, which has an RC element integrated into an insulating support on the drive side,

[0020] Figure 5B A high-voltage power switch according to the invention is shown, which has an RC element integrated into an insulating support on the fixed contact side,

[0021] Figure 6 shows a variant of the combination of RC elements according to the invention,

[0022] Figure 7 A first open-air insulated high-voltage arrester housing according to the invention with a single resistor and a capacitor is shown,

[0023] Figure 8 A second open-air insulated high-voltage arrester housing according to the invention with a single resistor and a capacitor is shown,

[0024] Fig.9A A live-tank power switch with an integrated RC element according to the present invention is shown.

[0025] Fig. 9B The RC element disk according to the present invention is arranged concentrically with the switch rod,

[0026] Fig.10 A dead-tank power switch according to the invention with an RC element integrated into the bushing is shown, and

[0027] Fig.11 A chassis-grounded power switch according to the invention with an RC element integrated into the support is shown.

[0028] In the drawings, like reference numerals denote like elements. DETAILED DESCRIPTION

[0029] The invention can be used in gas insulated applications (GIS) which belong to the category of tank container applications.

[0030] exist Figure 1 In the gas-insulated high-voltage device shown in , which can be designed as a single-pole or multi-pole device, conventional arresters are modified so that instead of arrester resistors, for example metal oxide (MO) resistors, individual resistor plates R and capacitors C are arranged.

[0031] Figure 2A and Figure 2B A single-pole cast resin bushing or a three-pole cast resin bushing is shown, in which the RC elements are integrated so that they are cast in the casting resin. Here, the conductor 22 to which the high voltage is applied is connected to the ground M via the corresponding RC element. The cast resin bushing according to the invention can be combined with an LPIT (Low Power Instrument Transformer).

[0032] exist Figure 3In the high voltage bushing / lead 23 of the gas insulated switchgear shown in FIG. 2 , two embodiments are shown, in which the RC element is arranged parallel to the bushing. Figure 3 As shown on the right, the RC element can be integrated into the casing of the bushing, on the one hand on the inner surface of the bushing, or on the other hand in the solid material of the bushing (ceramic, composite material, silicone, etc.). Figure 3 As shown on the left, the RC elements can be arranged in a stacked manner in a separate housing 19, wherein gas insulation, liquid insulation or solid insulation can be used for the RC elements.

[0033] exist Figure 4A In the high voltage bushing / lead-out 23 of the gas insulated switchgear shown in FIG. 1 , the RC element is integrated in the housing of the bushing, wherein the conductor 22 is connected to the electrode E located on the ground M or the outer housing of the bushing located on the ground M through the RC element. The RC element can be cast in a casting resin. Figure 4B As shown, the RC elements can be arranged as coaxial elements stacked around the conductor 22. Figure 4A In the embodiment, the diameter and / or the length of the region of the bushing / lead-out wire where the RC element is arranged can be designed to be larger than that of a conventional bushing / lead-out wire.

[0034] exist Figure 5A In the high-voltage power switch shown in FIG. , an RC element is arranged in an insulating support on the drive side of the circuit breaker unit UE. Figure 5B In the high-voltage power switch shown in FIG, an RC element is arranged in an insulating support on the fixed contact side of the circuit breaker unit UE. The RC element connected in series between the high voltage HV and the ground M can be cast into the insulating support, wherein solid insulation is provided. The RC element can be arranged in the gas chamber parallel to the support material of the insulating support.

[0035] Figure 6 The combination scheme of RC elements according to the present invention is shown. The RC connection can be carried out in different ways depending on the design, but also depending on the application, for example, always alternating small RC elements, large R elements and large C elements, different combinations of R elements and C elements (for example 2xR, 2xC), symmetrical or asymmetrical.

[0036] The present invention may be used in open air insulation applications (AIS).

[0037] exist Figure 7 In the embodiment shown in FIG. 1 , in an open-air insulated high-voltage arrester housing, instead of conventional arrester resistors, such as metal oxide (MO) resistors, according to the invention, individual resistor plates R and capacitors C are arranged in a stacked manner with gas insulation, liquid insulation or solid insulation.

[0038] exist Figure 8In the embodiment shown in FIG. 1 , in an open-air insulated high-voltage arrester housing, instead of conventional arrester resistors, such as metal oxide (MO) resistors, the present invention arranges individual resistors R and capacitors C in an insulated manner. The resistors R and capacitors C are spaced apart from the insulating housing 13 concentrically surrounding them by means of GFR rods uniformly distributed concentrically around them.

[0039] Fig.9A The live-tank circuit breaker shown in the figure can be implemented in a single-pole or multi-pole, in particular three-pole configuration. The circuit breaker unit UE in the housing is supported by the base 16 via an insulating support column 25 and can be operated by the drive 17 and a transmission device accommodated in the base 16 via an insulating switch rod 18 arranged in the support column. Fig.9A In the circuit breaker unit shown on the left, the RC element is arranged in a support column 25 next to the switching rod. Fig.9A In the circuit breaker unit shown on the right, in addition to the support column 25 with the switching rod 18, a separate RC column is arranged in an additional housing 19. RC elements with gas insulation, liquid insulation or solid insulation can be arranged in the RC column.

[0040] exist Fig.9A The circuit breaker unit shown in the center, as in Fig. 9B As shown in detail in a top view in FIG. 1 , the RC element 7 is arranged as an RC disk concentrically with the switching rod 18 in a stacked manner in a support column.

[0041] exist Fig.10 In the dead-tank circuit breaker shown in FIG. 2 , the interrupter unit UE is fixed in a housing located at ground M by means of an insulating support 20 and can be actuated by means of a drive 17 . The RC element 7 is integrated into the bushing 23 . Fig.10 The bushing 23 shown on the left in FIG. 4 can be provided by the high-voltage bushing / lead-out line described with respect to FIG. 4 . Fig.10 The sleeve 23 shown on the right side can be Figure 3 A description of the high voltage bushing / lead-out is given.

[0042] exist Fig.11 In the case of a grounded power switch shown in FIG, the circuit breaker unit UE is fixed in a housing located on the ground M by means of an insulating support 20. The RC element 7 is integrated in the insulating support on the fixed contact side of the circuit breaker unit facing away from the drive 17. The RC element 7 can be integrated into the insulating support on the drive side of the circuit breaker unit facing the drive.

[0043] exist Fig.11 Between the sleeve 23 shown on the right and the housing flange, a corresponding Figure 2AThe casting resin bushing 24 of the embodiment of the present invention is shown in FIG. The RC element is integrated into the casting resin bushing so that the RC element is cast into the casting resin. The casting resin bushing can be combined with a LPIT (Low Power Instrument Transformer).

[0044] Fig.10 and Fig.11 The shell grounding application shown in the figure belongs to the category of tank container application. Fig.10 and Fig.11 The housing grounded circuit breaker shown in FIG. 1 can be designed with one pole or with multiple poles, in particular with three poles.

[0045] The circuit breaker unit UE may comprise a high-voltage switch, in particular a high-voltage vacuum switch.

[0046] The wiring of an electrical device for high-voltage power transmission with an RC device according to the invention forms a protective circuit for a high-voltage switchgear, in particular a high-voltage vacuum switch.

[0047] In the context of the present invention, high voltage is understood to mean voltages of 72.5 kV (kilovolts) or higher, including direct voltages, alternating voltages and, in the case of three-pole, also three-phase currents.

[0048] For the purpose of illustration, the present invention has been described in detail with the aid of specific embodiments. Here, the elements of the various embodiments may also be combined with each other. Therefore, the present invention should not be limited to the various embodiments, but is only limited by the appended claims.

[0049] Reference numerals list

[0050] 1- Exhaust port

[0051] 2-Pressure relief unit

[0052] 3-Compression spring

[0053] 4- Sealing ring

[0054] 5-Pouring material

[0055] 6-Metal filler

[0056] 7-RC combination

[0057] 8-Retaining rod, glass fiber reinforced plastic (GFK)

[0058] 9-Retaining plate, glass fiber reinforced plastic (GFK)

[0059] 10-Porcelain shell

[0060] 11-Aluminum flange

[0061] 12-End fittings with high pressure connections

[0062] 13-Silicon shield

[0063] 14-GFK rod

[0064] 15-End fitting with foot, grounded

[0065] 16-Base, transmission

[0066] 17-Drive

[0067] 18-Switch rod, insulation rod

[0068] 19-Hood

[0069] 20-Insulation support, support

[0070] 21- Base

[0071] 22-Conductor

[0072] 23-Casing

[0073] 24-Casting resin sleeve

[0074] 25-Support column

[0075] AIS-Open Air Insulated Switchgear

[0076] C-capacitor, capacitance

[0077] E-Electrode

[0078] DT-Dead Tank

[0079] GIS - Gas Insulated Switchgear

[0080] HV - High Voltage

[0081] LPIT - Low Power Instrument Transformer

[0082] LT-Live Tank

[0083] M- ground, ground potential

[0084] MO-Metal Oxide

[0085] R - resistance

[0086] UE-Circuit Breaker Unit

Claims

1. A device for high voltage electrical energy transmission, wherein the high voltage (HV) is greater than or equal to 72.5 kV, It is characterized in that A series circuit is arranged between a conductor (22) carrying the high voltage (HV) and ground (M), the series circuit comprising at least one resistor R and at least one capacitor C.

2. The device according to claim 1, It is characterized in that The device is fed out via a high voltage bushing / lead-out line (23).

3. The device according to claim 2, It is characterized in that The device is configured as a cast resin sleeve (24).

4. The device according to claim 3, It is characterized in that The cast resin bushing is combined with a low power instrument transformer (LPIT).

5. The device according to claim 2, It is characterized in that A series circuit comprising at least one resistor R and at least one capacitor C is integrated into the casing (19) of the bushing.

6. The device according to claim 2, It is characterized in that A series circuit comprising at least one resistor R and at least one capacitor C is arranged in an additional housing (19) connected in parallel with the bushing (23).

7. The device according to claim 1, It is characterized in that The device is provided by a high-voltage power switch and a series circuit comprising at least one resistor R and at least one capacitor C is arranged in an insulating support (20) on the drive side or the fixed contact side of the circuit breaker unit UE.

8. The device according to claim 1, It is characterized in that The device is provided by a housing live power switch, and a series circuit comprising at least one resistor R and at least one capacitor C is arranged in parallel with the support column (25).

9. The device according to claim 1, It is characterized in that The device is provided by an arrester in which a series circuit comprising at least one resistor R and at least one capacitor C is arranged instead of the arrester resistor.

10. The device according to any one of the preceding claims, It is characterized in that The device has a vacuum switching device as a circuit breaker unit UE.

11. The device according to any one of the preceding claims, It is characterized in that The device is designed to be multipolar.

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