JP3750320B2

JP3750320B2 - Gas insulation apparatus and withstand voltage test method thereof

Info

Publication number: JP3750320B2
Application number: JP32368297A
Authority: JP
Inventors: 昌俊中島
Original assignee: Fuji Electric Systems Co Ltd
Current assignee: Fuji Electric Co Ltd
Priority date: 1997-11-26
Filing date: 1997-11-26
Publication date: 2006-03-01
Anticipated expiration: 2017-11-26
Also published as: JPH11164458A

Description

【０００１】
【発明の属する技術分野】
この発明は、絶縁ガスが封入された密閉容器内に避雷器を含む電気機器が収納されたガス絶縁機器、および、そのガス絶縁機器の耐電圧試験方法に関し、避雷器が収納されているガス区分室の絶縁ガスを抜かなくても耐電圧試験が実施できる方法に関する。
【０００２】
【従来の技術】
図３は、従来のガス絶縁機器の構成を示す要部断面図である。密閉容器１内が絶縁性のガス区分スペーサ５を介してガス区分室７Ａ，７Ｂに区分されるとともに、各ガス区分室７Ａ，７Ｂには高気圧、例えば、０．５ＭＰａのＳＦ₆ガスが封入されている。ガス区分室７Ａには、避雷器２が収納され、この避雷器２の高圧端２Ａが主回路導体４Ａに接続されている。避雷器２の接地端２Ｂは密閉容器１の底板１Ａに載置されている。接地端２Ｂには接地線３が接続され、この接地線３は底板１Ａを気密に貫通する気密端子６を介して外部の接地１２に結線されている。一方、主回路導体４Ａは、ガス区分スペーサ５を気密に貫通して主回路導体４Ｂに接続されている。主回路導体４Ｂは、図３の左方へさらに伸び、図示されていない他の電気機器に接続されている。他の電気機器とは、例えば、遮断器や断路器、計器用変成器などであり、一方、避雷器２は、主回路導体４Ｂに過電圧が発生したときに、その過電圧を吸収し他の電気機器に過電圧がかからないように保護している。
【０００３】
【発明が解決しようとする課題】
しかしながら、前述したようなガス絶縁機器は、耐電圧試験を実施する場合、避雷器に接続されている主回路導体をいちいち取り外さねばならないという問題があった。
すなわち、ガス絶縁機器の耐電圧試験時には、避雷器が動作するのを避ける必要がある。例えば、１５４ｋＶ系統のガス絶縁機器の場合、現地据え付け時の耐電圧試験では１７７ｋＶの試験電圧が印加される。一方、その系統に用いられる避雷器の動作開始電圧の下限値は１９６ｋＶである。避雷器の動作開始電圧と試験電圧とが非常に近いので、避雷器の動作開始電圧のばらつきによっては、避雷器が動作する可能性がある。避雷器自体が動作しては耐電圧試験が不可能になるので、避雷器だけには試験電圧がかからないようにして耐電圧試験が行われる。
【０００４】
図３において、従来は、ガス絶縁機器の耐電圧試験時に避雷器２の高圧端２Ａに接続されている主回路導体４Ａを一旦取り外し、他の電気機器に接続された主回路導体４Ｂだけに試験電圧を印加していた。すなわち、ガス区分室７ＡのＳＦ₆ガスを一旦抜いた後、上蓋１Ｂを開けて主回路導体４Ａを避雷器２の高圧端２Ａから外すとともに、外部に取り出していた。耐電圧試験後は、主回路導体４Ａを避雷器２の高圧端２Ａと主回路導体４Ｂとの間に接続し、上蓋１Ｂを閉じた後、再びＳＦ₆ガスをガス区分室７Ａに封入していた。そのために、耐電圧試験の前後に多大な試験準備工数を必要とし、ガス絶縁機器の現地据え付けに多くの時間がかかっていた。
【０００５】
この発明の目的は、避雷器が収納されているガス区分室の絶縁ガスを抜かなくても耐電圧試験ができるようにすることにある。
【０００６】
【課題を解決するための手段】
上記目的を達成するために、この発明によれば、絶縁ガスが封入された密閉容器内で主回路導体に結線された電気機器が収納され、この電気機器には主回路導体と接地間に介装された避雷器が含まれてなるガス絶縁機器において、前記避雷器の接地端が絶縁性のガス区分スペーサで絶縁支持され、反避雷器側のガス区分室に避雷器の接地端と着脱可能な接地線が収納されるようにするとよい。
【０００７】
また、かかる構成のガス絶縁機器の主回路導体に試験電圧を印加することによってガス絶縁機器の耐電圧試験を実施する方法であって、前記接地線が避雷器の接地端から外されるとともに反避雷器側のガス区分室に絶縁ガスが封入された状態で耐電圧試験が実施され、耐電圧試験後は、反避雷器側のガス区分室の絶縁ガスが抜かれるとともに避雷器の接地端に前記接地線が接続されるようにするとよい。それによって、ガス絶縁機器の耐電圧試験では、反避雷器側のガス区分室の接地線が避雷器の接地端から外されるとともに反避雷器側のガス区分室に絶縁ガスが封入されるだけなので、避雷器が収納されているガス区分室の絶縁ガスを抜かなくてもよくなる。一般に、反避雷器側のガス区分室は避雷器側のそれより小さい容積で済むので、絶縁ガスの出し入れ時間が少なくて済む。しかも、反避雷器側のガス区分室への絶縁ガスの封入作業は、耐電圧試験の前に一度行うだけでよい。一方、従来の方法では、前述のように、避雷器側のガス区分室へ絶縁ガスの封入作業を耐電圧試験の前と後とで２回行う必要がある。
【０００８】
【発明の実施の形態】
以下、この発明を実施例に基づいて説明する。図１は、この発明の実施例にかかるガス絶縁機器の構成を示す要部断面図である。密閉容器１の下部に絶縁性のガス区分スペーサ８を介してもう一つの密閉容器１１を形成し、この密閉容器１１の下部に底板１Ｃが取り付けられている。避雷器２の接地端２Ｃが絶縁性のガス区分スペーサ８で絶縁支持され、反避雷器側のガス区分室７Ｃ内には接地線９が設けられ、接地線９の一方端は避雷器２の接地端２Ｃにボルト留めされ、接地線９の他方端は気密端子１０にボルト留めされ、密閉容器１１の外部で接地１２に結線されている。図１のその他は、図３の従来の構成と同じであり、従来と同じ部分は同一参照符号を付けることによって詳細な説明は省略する。
【０００９】
図１は実際の使用状態の構成である。ガス区分室７Ａ内にはＳＦ₆ガスが封入されているが、ガス区分室７Ｃ内は接地線９が収納されているだけなので、大気が封入されてあればよい。
図２は、図１のガス絶縁機器が耐電圧試験される状態を示す要部断面図である。密閉容器１１内には接地線はなく、避雷器２の接地端２Ｃが電位的に浮いた状態にあり、ガス区分室７ＣにはＳＦ₆ガスが封入されている。この状態で、主回路導体４Ｂに試験電圧が印加され、ガス絶縁機器の耐電圧試験が実施される。避雷器２の高圧端２Ａには電圧が印加されるが、接地端２Ｃが接地されていないので、避雷器２には僅かの電圧しか発生しない。避雷器２の高圧端２Ａと接地端２Ｃとの間の静電容量が一般に数十ｐＦであり、接地端２Ｃとその周囲の密閉容器１１との間の静電容量が数ｐＦ程度なので、避雷器２には試験電圧値の１割程度しかかからない。したがって、避雷器２の高圧端２Ａに試験電圧が印加されても、図２の状態ならば避雷器２が動作することは決してない。接地端２Ｃと密閉容器１１との間には、試験電圧値の９割がかかるが、絶縁耐力の高いＳＦ₆ガスが封入されているので、絶縁は充分に耐えられる。耐電圧試験終了後は、密閉容器１１内のＳＦ₆ガスを抜くとともに底板１Ｃを取り外し、接地線９を避雷器２の接地端２Ｃと気密端子１０にボルト留めする。その後、底板１Ｃは密閉容器１１に取り付けられ図１の構成に戻されるが、密閉容器１１内にＳＦ₆ガスを再封入する必要はなく、大気状態のままでよい。
【００１０】
図２において、一般に、ガス区分室７Ｃは、避雷器２側のガス区分室７Ａより小さい容積で済むので、ＳＦ₆ガスの出し入れ時間も少なくて済む。しかも、ガス区分室７ＣへのＳＦ₆ガスの封入作業は、耐電圧試験の前に一度行うだけである。前述のように、従来の方法では、避雷器２側のガス区分室７ＡへＳＦ₆ガスを封入する作業を耐電圧試験の前と後ので２回行う必要があった。この発明の方法によって、耐電圧試験の準備工数が大幅に減り、ガス絶縁機器の現地据え付け時間が短縮される。
【００１１】
【発明の効果】
この発明は前述のように、絶縁ガスが封入された密閉容器内で主回路導体に結線された電気機器が収納され、この電気機器には主回路導体と接地間に介装された避雷器が含まれてなるガス絶縁機器において、前記避雷器の接地端が絶縁性のガス区分スペーサで絶縁支持され、反避雷器側のガス区分室に避雷器の接地端と着脱可能な接地線が収納される。それによって、ガス絶縁機器の耐電圧試験の準備工数が大幅に減った。そのために、ガス絶縁機器の現地据え付けの時間が短縮され、納期の短縮と試験費用の節約が可能になった。
【図面の簡単な説明】
【図１】この発明の実施例にかかるガス絶縁機器の構成を示す要部断面図
【図２】図１のガス絶縁機器が耐電圧試験される状態を示す要部断面図
【図３】従来のガス絶縁機器の構成を示す要部断面図
【符号の説明】
１，１１：密閉容器、２：避雷器、２Ａ：高圧端、２Ｂ，２Ｃ：接地端、３，９：接地線、４Ａ，４Ｂ：主回路導体、５，８：ガス区分スペーサ、７Ａ，７Ｂ，７Ｃ：ガス区分室、１２：接地[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas insulated device in which an electric device including a lightning arrester is housed in a sealed container in which an insulating gas is sealed, and a withstand voltage test method for the gas insulated device. The present invention relates to a method capable of performing a withstand voltage test without removing an insulating gas.
[0002]
[Prior art]
FIG. 3 is a cross-sectional view of a main part showing the configuration of a conventional gas insulation device. The airtight container 1 is divided into gas compartments 7A and 7B through insulating gas compartment spacers 5, and each gas compartment 7A and 7B is filled with high pressure, for example, 0.5 MPa SF ₆ gas. ing. The lightning arrester 2 is accommodated in the gas compartment 7A, and the high voltage end 2A of the lightning arrester 2 is connected to the main circuit conductor 4A. The grounding end 2 </ b> B of the lightning arrester 2 is placed on the bottom plate 1 </ b> A of the sealed container 1. A ground line 3 is connected to the ground end 2B, and the ground line 3 is connected to an external ground 12 through an airtight terminal 6 that airtightly penetrates the bottom plate 1A. On the other hand, the main circuit conductor 4A penetrates the gas partition spacer 5 in an airtight manner and is connected to the main circuit conductor 4B. The main circuit conductor 4B extends further to the left in FIG. 3 and is connected to other electrical equipment not shown. The other electrical equipment is, for example, a circuit breaker, a disconnector, an instrument transformer, etc. On the other hand, the lightning arrester 2 absorbs the overvoltage when the overvoltage is generated in the main circuit conductor 4B, and the other electrical equipment. Is protected from overvoltage.
[0003]
[Problems to be solved by the invention]
However, the gas insulating device as described above has a problem that the main circuit conductor connected to the lightning arrester must be removed one by one when the withstand voltage test is performed.
In other words, it is necessary to avoid the operation of the lightning arrester during the withstand voltage test of the gas insulation equipment. For example, in the case of a gas insulation device of a 154 kV system, a test voltage of 177 kV is applied in a withstand voltage test at the time of field installation. On the other hand, the lower limit value of the operation start voltage of the lightning arrester used in the system is 196 kV. Since the operation start voltage of the lightning arrester is very close to the test voltage, the lightning arrester may operate depending on variations in the operation start voltage of the lightning arrester. Since the withstand voltage test becomes impossible when the lightning arrester itself operates, the withstand voltage test is performed so that the test voltage is not applied only to the lightning arrester.
[0004]
In FIG. 3, in the past, the main circuit conductor 4A connected to the high-voltage end 2A of the lightning arrester 2 was once removed during a withstand voltage test of the gas insulation device, and the test voltage was applied only to the main circuit conductor 4B connected to another electrical device. Was applied. That is, after the SF ₆ gas in the gas compartment 7A was once extracted, the upper lid 1B was opened to remove the main circuit conductor 4A from the high voltage end 2A of the lightning arrester 2 and to the outside. After the withstand voltage test, the main circuit conductor 4A was connected between the high-voltage end 2A of the lightning arrester 2 and the main circuit conductor 4B, the upper lid 1B was closed, and SF ₆ gas was again enclosed in the gas compartment 7A. . For this reason, a large number of test preparation man-hours were required before and after the withstand voltage test, and it took a lot of time to install the gas-insulated equipment on-site.
[0005]
An object of the present invention is to enable a withstand voltage test without removing an insulating gas from a gas compartment containing a lightning arrester.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, an electrical device connected to a main circuit conductor is accommodated in a sealed container filled with an insulating gas, and the electrical device is interposed between the main circuit conductor and the ground. In the gas-insulated equipment including the mounted arrester, the grounding end of the arrester is insulated and supported by an insulating gas section spacer, and the grounding end of the arrester and the detachable ground line are provided in the gas section chamber on the anti-lightning arrester side. It should be stored.
[0007]
A method of performing a withstand voltage test of a gas insulated device by applying a test voltage to a main circuit conductor of the gas insulated device having such a configuration, wherein the grounding wire is disconnected from the grounding end of the lightning arrester and the anti-lightning device Withstand voltage test is performed with the insulation gas sealed in the gas compartment on the side, and after the withstand voltage test, the insulation gas is removed from the gas compartment on the anti-lightning arrester side and the ground wire is connected to the grounding end of the arrester. It is good to be connected. As a result, in the withstand voltage test of gas insulation equipment, the grounding wire of the gas compartment on the anti-lightning arrester side is disconnected from the grounding end of the lightning arrester and the insulating gas is only sealed in the gas compartment on the anti-lightning device side. It is not necessary to remove the insulating gas from the gas compartment in which the gas is stored. In general, the gas compartment on the anti-lightning arrester side has a smaller volume than that on the lightning arrester side, so that the time for taking in and out the insulating gas can be reduced. In addition, the operation of sealing the insulating gas into the gas compartment on the side of the anti-lightning arrester need only be performed once before the withstand voltage test. On the other hand, in the conventional method, as described above, it is necessary to perform the operation of sealing the insulating gas into the gas compartment on the lightning arrester side twice before and after the withstand voltage test.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on examples. FIG. 1 is a cross-sectional view of a principal part showing the configuration of a gas insulation device according to an embodiment of the present invention. Another sealed container 11 is formed at the lower part of the sealed container 1 via an insulating gas partition spacer 8, and a bottom plate 1 C is attached to the lower part of the sealed container 11. The grounding end 2C of the lightning arrester 2 is insulated and supported by an insulating gas partition spacer 8, a grounding wire 9 is provided in the gas compartment 7C on the anti-lightning arrester side, and one end of the grounding wire 9 is the grounding end 2C of the lightning arrester 2. The other end of the ground wire 9 is bolted to the airtight terminal 10 and connected to the ground 12 outside the sealed container 11. The other parts of FIG. 1 are the same as those of the conventional configuration of FIG.
[0009]
FIG. 1 shows a configuration in an actual use state. SF ₆ gas is enclosed in the gas compartment 7A, but the ground line 9 is only accommodated in the gas compartment 7C, so it is sufficient that the atmosphere is enclosed.
FIG. 2 is a cross-sectional view of a principal part showing a state in which the gas insulation apparatus of FIG. 1 is subjected to a withstand voltage test. There is no ground wire in the sealed container 11, the ground end 2C of the lightning arrester 2 is in a potential floating state, and SF ₆ gas is sealed in the gas compartment 7C. In this state, a test voltage is applied to the main circuit conductor 4B, and a withstand voltage test of the gas insulating device is performed. Although a voltage is applied to the high-voltage end 2A of the lightning arrester 2, the grounding end 2C is not grounded, so that only a small voltage is generated in the lightning arrester 2. Since the electrostatic capacitance between the high-voltage end 2A and the grounding end 2C of the lightning arrester 2 is generally several tens pF, and the electrostatic capacitance between the grounding end 2C and the surrounding sealed container 11 is about several pF, the lightning arrester 2 Takes only about 10% of the test voltage value. Therefore, even if a test voltage is applied to the high-voltage end 2A of the lightning arrester 2, the lightning arrester 2 will never operate in the state shown in FIG. Although 90% of the test voltage value is applied between the grounding end 2C and the sealed container 11, since the SF ₆ gas having a high dielectric strength is sealed, the insulation can be sufficiently tolerated. After completion of the withstand voltage test, the SF ₆ gas in the sealed container 11 is removed and the bottom plate 1C is removed, and the ground wire 9 is bolted to the ground end 2C of the lightning arrester 2 and the airtight terminal 10. Thereafter, the bottom plate 1C is attached to the sealed container 11 and returned to the configuration of FIG. 1, but it is not necessary to re-enclose the SF ₆ gas in the sealed container 11, and it may remain in the atmospheric state.
[0010]
In FIG. 2, the gas compartment 7C generally has a smaller volume than the gas compartment 7A on the lightning arrester 2 side, so that the time for taking in and out the SF ₆ gas can be reduced. Moreover, the SF ₆ gas filling operation into the gas compartment 7C is performed only once before the withstand voltage test. As described above, according to the conventional method, it is necessary to perform the work of filling the SF ₆ gas into the gas compartment 7A on the lightning arrester 2 side twice before and after the withstand voltage test. By the method of the present invention, the man-hours required for the withstand voltage test are greatly reduced, and the time for installing the gas-insulated equipment on site is shortened.
[0011]
【The invention's effect】
As described above, the present invention stores an electrical device wired to the main circuit conductor in a sealed container filled with an insulating gas, and the electrical device includes a lightning arrester interposed between the main circuit conductor and the ground. In the gas insulated device, the grounding end of the lightning arrester is insulated and supported by an insulating gas section spacer, and the grounding end of the lightning arrester and the detachable grounding line are accommodated in the gas section chamber on the anti-lightning arrester side. As a result, the man-hours required for the withstand voltage test for gas-insulated equipment have been greatly reduced. As a result, the time for on-site installation of gas insulation equipment has been shortened, enabling shorter delivery times and saving on test costs.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part showing a configuration of a gas insulation device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a main part showing a state in which the gas insulation device of FIG. Sectional view showing the configuration of the gas insulation equipment of the main part 【Explanation of symbols】
DESCRIPTION OF SYMBOLS 1,11: Airtight container, 2: Lightning arrester, 2A: High voltage | pressure end, 2B, 2C: Grounding end, 3, 9: Grounding wire, 4A, 4B: Main circuit conductor, 5, 8: Gas division spacer, 7A, 7B, 7C: Gas compartment, 12: Ground

Claims

In a gas insulated device in which an electrical device wired to the main circuit conductor is stored in a sealed container filled with an insulating gas, and this electrical device includes a lightning arrester interposed between the main circuit conductor and the ground, A gas insulating apparatus characterized in that the grounding end of the lightning arrester is insulated and supported by an insulating gas section spacer, and the grounding end of the lightning arrester and a detachable grounding line are housed in the gas section chamber on the side of the anti-lightning arrester.

A method for performing a withstand voltage test of a gas insulated device by applying a test voltage to a main circuit conductor of the gas insulated device according to claim 1, wherein the ground wire is disconnected from a ground end of a lightning arrester and A withstand voltage test is performed in a state where an insulation gas is sealed in the gas compartment on the lightning arrester side.After the withstand voltage test, the insulation gas in the gas compartment on the anti-lightning arrester side is removed and the ground wire is connected to the grounding end of the lightning arrester. A withstand voltage test method for gas insulated equipment, characterized in that is connected.