JPH10201028A - Faulty point orientation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a faulty point orientation device which uses a small amount of wire rod and which is economical and is easily maintained. SOLUTION: This device is provided with two resistance wires 6a, 6b which are installed along a gas insulation equipment and whose one ends are shorted, an ohmmeter 7 for detecting a resistance value RA between the other ends of the resistance wires, and a faulty point orientation circuit 5 for orientating a faulty point based on a change in the resistance value RA. One ends of gas density switches S1-Sn are connected to different points of one 6a of the two resistance wires and the other ends of the gas density switches S1-Sn are connected to different points of the other 6b of the two resistance wires in correspondence with the points to which one ends are connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fault point locating device such as a gas insulated device for power transmission (hereinafter referred to as GIS), and more particularly to a method for locating each fault point using a small number of wires even for a long GIS. It relates to a possible fault locating device.

[0002]

2. Description of the Related Art Generally, gas insulated equipment for substations for insulating high voltage for power transmission, that is, GIS (Gas Ins).
In the case of a substation or the like, it is necessary to always detect occurrence of a short-circuit failure inside the tank in order to ensure safety and reliability.

[0003] Conventionally, when a short-circuit fault occurs, the GI
A device for locating a failure point based on the on / off operation state of each gas density switch by arranging a plurality of gas density switches for each gas section of the GIS tank by utilizing the increase in the gas pressure in the S tank. Has been proposed.

FIG. 11 shows, for example, Japanese Patent Laid-Open No. 7-25511.
FIG. 1 is a configuration diagram illustrating a conventional GIS fault point locating device described in Japanese Unexamined Patent Publication (Kokai) No. 1-No. In FIG. 11, reference numeral 1 denotes a tank-shaped GIS for which a failure point is to be located. Being GI
This is the center conductor passed through S1.

[0005] S1 to Sn are gas density switches individually disposed in the respective gas sections G1 to Gn.
It is turned on by the increase in gas pressure in 1 to Gn, and monitors the occurrence of a short-circuit failure.

Reference numeral 5 denotes a fault point locating circuit having various calculation judging functions and the like.
The fault points in the IS 1 are located, and the location results are displayed and an alarm is issued.

Next, the operation of the conventional fault locator shown in FIG. 11 will be described. For example, if a ground fault occurs in gas section G2 during GIS1 operation,
Since the gas pressure in the gas section G2 increases, the gas density switch S2 is turned on to output the switch contact signal W2.

Thus, the fault point locating circuit 5 locates the occurrence of a short-circuit failure in the gas section G2 based on the switch contact signal W2, and displays the location result on a display screen (not shown) as a warning. As a result, the monitor or the operator stops the operation of the GIS 1 to repair the short-circuit failure state, and restarts the operation of the GIS 1 after the completion of the repair.

[0009] However, GIS1 has a GIL (Ga
s Insulated Transmission
In the case of a long-distance type such as an underground type called Line), in order to monitor the operation of each gas density switch at one end of the GIL, a large amount of wire drawn from the output terminal of each gas density switch is required. It is economical and requires a great deal of maintenance.

In particular, in the case of a GIL buried underground, the burial distance reaches several kilometers and the number of gas sections to be monitored also reaches 100 or more. Therefore, the contact output of each gas density switch is simply set to the GIL. If you try to pull it out at one end, you will need several hundred kilometers of wire.

[0011]

As described above, the conventional fault point locating device simply draws out the contact output of each of the gas density switches S1 to Sn. A wire rod of 100 km is required, which is uneconomical and maintenance is difficult.

The present invention has been made in order to solve the above problems, and requires a small amount of wire.
It is an object of the present invention to obtain an economical and easy-to-maintain fault locating device.

[0013]

According to a first aspect of the present invention, there is provided a failure point locating apparatus, wherein a gas density switch is individually arranged in each gas section of a gas insulated device, and an operation state of each of the gas density switches is provided. A fault point locating device for locating a fault point in a gas insulated device based on the two resistance wires disposed along the gas insulated device and having one end short-circuited and the other end of the resistance wire. And a failure point locating circuit for locating a failure point based on a change in the resistance value. Each end of the gas density switch has a different position on one of the two resistance wires. And the other ends of the gas density switches are connected to the other of the two resistance wires at different positions so as to correspond to the positions of the one ends.

According to a second aspect of the present invention, there is provided a fault point locating device according to the first aspect, wherein the fault point locating circuit includes a resistance value detected by an ohmmeter and a latest combined resistance value of the two resistance wires. The fault point is located based on the ratio with the value.

According to a third aspect of the present invention, there is provided a fault point locating apparatus according to the first aspect, wherein each connection point of the gas density switch with respect to the resistance wire is arranged at a position spaced apart by a power of two. It is a thing.

According to a fourth aspect of the present invention, there is provided a failure point locating apparatus, wherein a gas density switch is individually disposed in each gas section of a gas insulating device, and a gas density switch is provided based on an operation state of each gas density switch. In a fault point locating device for locating a fault point in an insulating device, a plurality of relays disposed along the gas insulating device and individually connected to each gas density switch, and disposed along the gas insulating device. A ladder network composed of a plurality of resistor pairs, a plurality of relay contacts driven by each relay and individually switching a connection state of each resistor pair, a power supply connected to the ladder network,
It has an ammeter that detects the current value flowing through the ladder network, and a fault point locating circuit that locates a fault point based on a change in the current value, and one resistance value of each resistor pair is connected in series with each other. Forming a loop circuit, the other resistor of each resistor pair has twice the resistance of one resistor, and is connected in parallel through one end of each resistor in the loop circuit; The relay contacts are activated when each gas density switch is activated.
An ammeter is inserted between each other end of the other resistor and the common end of the loop circuit.

According to a fifth aspect of the present invention, there is provided a failure point locating apparatus, wherein a gas density switch is individually arranged in each gas section of a gas insulating device, and a gas density switch is provided based on an operation state of each gas density switch. In a fault point locating device for locating a fault point in an insulated device, a loop circuit including a plurality of capacitors arranged along the gas insulated device and connected in series with each other, and a capacitance value of the loop circuit are detected. A capacitance meter and a failure point locating circuit for locating a failure point based on a change in the capacitance value are provided.
The other ends of the gas density switches are connected to different connection points of adjacent capacitors in the loop circuit, and the other ends of the gas density switches are connected to a common end of the loop circuit.

According to a sixth aspect of the present invention, in the fault locating device according to the fifth aspect, the fault locating circuit includes a capacitance value detected by a capacitance meter and a latest total electrostatic capacity of the loop circuit. The fault point is located based on the ratio with the capacity value.

According to a seventh aspect of the present invention, there is provided a failure point locating device, wherein a gas density switch is individually arranged in each gas section of a gas insulating device, and a gas density switch is provided based on each operating state of the gas density switch. In a fault point locating device for locating a fault point in an insulated device, a network circuit including a plurality of capacitors arranged along the gas insulated device and connected in parallel with each other, and a capacitance value of the network circuit are detected. A capacitance meter; and a failure point locating circuit for locating a failure point based on a change in capacitance value. Each gas density switch includes a normally closed contact, and is connected between each end of an adjacent capacitor in the network circuit. Are inserted differently from each other.

In the fault locating device according to claim 8 of the present invention, the fault locating circuit according to claim 7 includes a capacitance value detected by a capacitance meter and a latest total electrostatic capacitance of a network circuit. The fault point is located based on the ratio with the capacity value.

According to a ninth aspect of the present invention, there is provided a failure point locating apparatus, wherein a gas density switch is individually arranged in each gas section of a gas insulating device, and a gas density switch is provided based on an operation state of each gas density switch. In a fault point locating device for locating a fault point in an insulating device, a loop circuit including a plurality of reactors arranged along a gas insulating device and connected in series to each other, and an inductance meter for detecting an inductance value of the loop circuit. And a failure point locating circuit for locating a failure point based on a change in the inductance value.Each one end of the gas density switch is connected to a different connection point between adjacent reactors in the loop circuit, Each other end of the switch is connected to a common end of the loop circuit.

According to a tenth aspect of the present invention, in the ninth aspect, the fault locating circuit comprises: an inductance value detected by an inductance meter;
The fault point is located based on the ratio with the latest total inductance value of the loop circuit.

[0023] In the fault locating device according to claim 11 of the present invention, a gas density switch is individually arranged in each gas section of the gas insulated equipment, and a gas density switch is provided based on each operation state of the gas density switch. In a fault point locating device for locating a fault point in an insulating device, a network circuit including a plurality of LC tank circuits arranged along a gas insulating device and connected in parallel with each other, and an impedance value of the network circuit are detected. An impedance meter and a fault point locating circuit for locating a fault point based on a change in impedance value are provided. Each LC tank circuit has a different resonance frequency, and each gas density switch is individually connected to a different LC tank circuit. Are connected in series.

According to a twelfth aspect of the present invention, in the eleventh aspect, the fault locating circuit comprises:
Based on the specific frequency at which the impedance value shows a maximum,
This is for locating a failure point.

According to a thirteenth aspect of the present invention, there is provided a failure point locating apparatus, wherein a gas density switch is individually arranged in each gas section of a gas insulating device, and a gas density switch is provided based on each operating state of the gas density switch. In a fault locating device for locating a fault in an insulating device, a network circuit including a plurality of oscillating circuits arranged along a gas insulating device and connected in parallel with each other, and a power supply for driving each oscillating circuit are provided. When,
A spectrum analyzer that detects the oscillation frequency value of the network circuit, a DC blocking capacitor inserted between one end of the network circuit and the spectrum analyzer, and a high frequency blocking capacitor inserted between one end of the network circuit and the power supply And a failure point locating circuit for locating a failure point based on a change in the spectrum of the oscillation frequency value.Each oscillation circuit has a different oscillation frequency, and each gas density switch is individually connected to a different oscillation circuit. Are connected in series.

[0026] According to a fourteenth aspect of the present invention, in the thirteenth aspect, a diode individually connected in parallel to each of the gas density switches and a network from a power source under the control of the fault location circuit. Polarity inverting means for inverting the power supply polarity to the circuit, wherein the polarity inversion means sets the power supply polarity to the reverse polarity with respect to the forward direction of the diode during normal failure monitoring, and the diode during self-diagnosis of the oscillation circuit. Is set to the same polarity as the forward direction of.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the present invention. In FIG.
, And S1 to Sn are the same gas density switches as described above. Although not shown here, the configuration of the GIS 1 is as shown in FIG.

6a and 6b are GIS1 (see FIG. 11)
Are two resistance wires arranged in parallel outside the GIS 1 along the direction of the extension axis, and one end 6c of each of the resistance wires 6a and 6b is short-circuited to form a loop shape.

Each portion between the resistance lines 6a and 6b corresponds to each of the gas sections G1 to Gn of the GIS 1,
N gas density switches S1 to Sn are individually and sequentially connected to the respective portions of the resistance wires 6a and 6b.

That is, one ends of the gas density switches S1 to Sn are connected to different positions of one resistance wire 6a, and the other ends of the gas density switches S1 to Sn are
The other resistance wire 6b is connected to different positions so as to correspond to the position of each one end.

In this case, each of the gas density switches S1 to Sn
Are connected on the resistance lines 6a and 6b sequentially at equal intervals d so as to be short-circuited between the connection points with the resistance lines 6a and 6b during the ON operation.

Reference numeral 7 denotes a resistance meter for detecting the resistance value RA between the open ends of the resistance wires 6a and 6b, that is, the other ends. The failure point locating circuit 5A locates a failure point based on a change in the resistance value RA detected by the resistance meter 7.

Next, the operation of the first embodiment of the present invention shown in FIG. 1 will be described by taking as an example a case where the GIS 1 is set as the fault point target in the same manner as described above. First, GIS1
In a normal operating state where there is no ground fault and no gas density switches S1 to Sn are turned on, the resistance value RA detected by the resistance meter 7 is the combined resistance value of the two resistance wires 6a and 6b. Is shown.

That is, assuming that the resistance value of each of the resistance lines 6a and 6b is Ra [Ω], the gas density switch S
1 to Sn when not operating (when GIS1 is normal)
Is 2 · Ra [Ω].

Here, for example, the i-th gas section Gi
Then, when a ground fault occurs and the i-th gas density switch Si is turned on, the detected resistance value RAi is expressed by the following equation (1).

RAi = {(i−1) / n} × 2 · Ra (1)

Therefore, the fault point locating circuit 5A
The position i of the gas density switch Si can be obtained from the following equation (2) based on the resistance value RAi in equation (1).

I = {RAi / (2 · Ra)} × n + 1 (2)

As the combined resistance value 2.Ra in the equation (2), an initial measurement value when the resistance wires 6a and 6b are installed may be used, but when the gas density switches S1 to Sn are not operated. It is desirable to use the latest measurements at Because, by using the latest measured value, the detection resistance value RA
This is because the change factors that equally affect i and the combined resistance value 2 · Ra are offset by the division in the expression (2).

In general, when a resistance change coefficient α such as a temperature characteristic and an average aging is considered, the detected resistance value RAi and the combined resistance value 2 · Ra are α · RAi and α · 2 · Ra, respectively. The expression (2) is expressed as the following expression (3).

I = (α · RAi / α · 2 · Ra) × n + 1 (3)

Therefore, from the equation (3), the resistance change coefficient α
Is apparently canceled out, and Equation (2) is derived.
It can be seen that the result of locating the failure point i is not substantially affected by the change in the resistance value.

As described above, by inserting the contacts of the gas density switches S1 to Sn at different positions of the resistance wires 6a and 6b, the resistance value RA corresponding to the position i of the fault point can be detected. The fault point can be located by the resistance value RA itself.

Further, as shown in equation (2), the ratio RAi / (2 · R) of the change from the combined resistance value 2 · Ra that is constantly measured.
By determining Ra) and locating the fault point i from this value, it is possible to locate the fault point i in which the average temperature characteristic of the resistance value is compensated.

In the first embodiment, the resistance line 6a
And 6b, it is assumed that the resistance values of the sections at equal intervals d are equal. Therefore, when two or more of the gas density switches S1 to Sn operate simultaneously, a failure point cannot be detected. If a resistance value in each section of the lines 6a and 6b is given a weight of a power of 2, even if a plurality of fault points occur, it can be detected.

In this case, each of the gas density switches S1 to Sn
Are not connected at equal intervals on the resistance lines 6a and 6b, but are connected so that the positions of the connection points are sequentially separated by a power of two.

Embodiment 2 In the first embodiment, the resistance wires 6a and 6b and the gas density switches S1 to S
The fault point was located based on the resistance value RA corresponding to the fault point in combination with the contact point n, but the current value according to the occurrence of the fault point was determined using a known ladder network composed of a plurality of resistor pairs. A fault point may be located from a change in (or resistance value).

Hereinafter, a second embodiment of the present invention using a ladder network will be described with reference to the drawings. FIG. 2 is a configuration diagram showing a second embodiment of the present invention. In FIG.
5B corresponds to the fault point locating circuit 5A described above (see FIG. 1), and S1 to Sn are the same as those described above.

P1 to Pn are a plurality of relays arranged along the GIS 1 (see FIG. 11) and are individually connected in series to the respective gas density switches S1 to Sn. Reference numeral 8 denotes a DC power supply for driving each of the relays P1 to Pn, and the anode is connected to each of the relays P1 to Pn via each of the gas density switches S1 to Sn.
The cathode (ground side) is connected to one end of Pn, and the other end of each of the relays P1 to Pn.

Ri and Ri (i = 1 to n) are relays P
There are n inverted L-shaped resistor pairs (ladders) arranged along the GIS 1 corresponding to 1 to Pn, and constitute a known ladder network NT. r0 is a resistor inserted at the end of the ladder network NT.

The ladder network NT is a general one used for a D / A converter and the like. The resistance value of one of the resistors R1 to Rn of each of the resistor pairs ri and Ri is equal to that of the other resistor. The resistance is set to twice the resistance value of the devices r1 to rn.

Q1 to Qn are a plurality of relay contacts driven by each of the relays P1 to Pn, which are individually connected in series to each of the resistor pairs ri and Ri in the ladder network NT. The connection state of Ri is individually switched, and each ladder is turned on / off.

That is, each of the relay contacts Q1 to Qn responds to the energizing operation of the relays P1 to Pn, and each of the resistors R1 to Rn.
One end of Rn is switched from the contact b side (the state shown) on the ground side to the contact a side to be connected.

Reference numeral 9 denotes a DC power supply for supplying a constant voltage to the ladder network NT.
n series circuits, and the cathode (ground side) is connected to the ground contact b side of each of the relay contacts Q1 to Qn.

Reference numeral 10 denotes an ammeter for detecting a current value IA flowing through the ladder network NT.
It is inserted between the contact a of Qn and the ground. The fault point locating circuit 5B outputs the current value IA detected by the ammeter 10.
Based on the change, the switching state of the ladder network is monitored to locate a fault point.

Next, taking the case where the GIS 1 is targeted for fault location as an example, the second embodiment of the present invention shown in FIG.
Will be described. From the characteristics of the ladder network NT, for example, the relay contact Q4 (not shown) has 1 [m
A], the voltage of the power supply 9 is adjusted so that the relay contacts Q1, Q2, and Q3 have 8 [mA], 4
[MA] and 2 [mA] current flow.

From the above characteristics, as shown in Table 1 below, by monitoring the current value IA detected by the ammeter 10, the operation status of the gas density switches S1 to Sn can be known.

[0058]

[Table 1] Current value IA S1 S2 S3 S40 0 [mA] × × × × 1 [mA] × × × ○ 2 [mA] × × ○ × 3 [mA] × × ○ ○ 4 [mA] × ○ × × 5 [mA] × ○ × ○ 6 [mA] × ○ ○ × 7 [mA] × ○ ○ ○ 8 [mA] ○ × × × 9 [mA] ○ × × ○ 10 [mA] ○ × ○ × 11 [MA] ○ × ○ ○ 12 [mA] ○ ○ × × 13 [mA] ○ ○ × ○ 14 [mA] ○ ○ ○ × 15 [mA] ○ ○ ○ ○

Table 1 shows the case where the number n of the gas density switches is four for simplification. In Table 1, the state of each of the gas density switches S1 to S4 is "OFF", and "O" is the state.
Indicates an on (failure occurring) state.

As is clear from Table 1, the fault point locating circuit 5B uniquely determines all the on / off states of the gas density switches S1 to Sn in accordance with the detected current value IA, and The operating state of the gas density switch can also be monitored.

In the second embodiment, the fault point is located based on the change in the current value IA flowing through the ladder network NT. However, the change in the combined resistance value of the ladder network NT is determined using the same resistance meter 7 as described above. The fault point may be located from the.

Embodiment 3 In the second embodiment, the fault point is located using the ladder network NT including a plurality of resistor pairs. However, the capacitance value of the loop circuit is determined using a loop circuit in which a plurality of capacitors are connected in series. A failure point may be located from the change.

Hereinafter, a third embodiment of the present invention using a capacitor loop circuit will be described with reference to the drawings. FIG. 3 is a block diagram showing a third embodiment of the present invention. In FIG. 3, reference numeral 5C corresponds to the above-described fault locating circuit 5A or 5B, and S1 to Sn are the same as those described above.

C1 to Cn are a plurality of capacitors arranged along GIS1 (see FIG. 11) and connected in series with each other, and together with the capacitor C0 inserted at the end, constitute a loop circuit PC. .

The capacitors C1 to Cn correspond to the gas sections G1 to Gn of the GIS 1, respectively.
Each of the gas density switches S1 to Sn is individually and sequentially connected to one end of Cn.

That is, one end of each of the gas density switches S1 to Sn is connected to a different connection point between adjacent capacitors in the loop circuit PC.
To Sn are connected to a common end of the loop circuit PC. Accordingly, the capacitor Ci and the gas density switch Si (i = 1 to n) corresponding to each gas section Gi are provided.
Form an inverted L-shaped n-stage network.

Reference numeral 11 denotes a capacitance meter for detecting a capacitance value CA of the loop circuit PC, which is connected between open ends of the loop circuit PC. The failure point locating circuit 5C locates a failure point based on a change in the capacitance value CA detected by the capacitance meter 11.

Next, the operation of the third embodiment of the present invention shown in FIG. 3 will be described. Normally, gas density switch S
When 1 to Sn are not operating, the overall capacitance value CAo of the loop circuit PC detected by the capacitance meter 11 is represented by the following equation (4).

CAo = Ca / (n + 1) (4)

In the equation (4), Ca represents each capacitor C
It is a capacitance value for one of 0 to Cn, and is assumed to be equal to each other. Here, when a ground fault occurs in the i-th gas section Gi and the gas density switch Si is turned on, the capacitance value CAi detected by the capacitance meter 11 is expressed by the following equation (5). Is represented.

CAi = Ca / i (5)

Therefore, the fault point locating circuit 5C can specify the position i of the gas density switch Si that has been turned on by the following equation (6) from the above equations (4) and (5).

I = (CAo / CAi) × (n + 1) (6)

As the total capacitance value CAo in the equation (6), an initial measurement value when the capacitors C1 to Cn are installed may be used. However, when the gas density switches S1 to Sn are not operated, It is desirable to use the latest measured values of Thus, the total capacitance value CAo and the detected capacitance value CA
Temperature characteristics and average aging that are equally effective for i can be offset by division in equation (6).

Here, when the capacitance change coefficient β such as temperature characteristics and average aging is considered, the total capacitance value CAo
And the detected capacitance value CAi are β · CAo, respectively.
And β · CAi, and the equation (6) is expressed as the following equation (7).

I = {βCAo / (βCAi)} × (n + 1) (7)

Therefore, from the equation (7), the resistance change coefficient β
Is apparently canceled out to lead to equation (6).
It can be seen that the result of locating the failure point i is not affected by the change in the capacitance value.

As described above, the gas divisions G1 to G
The capacitors C1 to Cn corresponding to every n are arranged in a series loop, and the connection points of the capacitors C1 to Cn are short-circuited via the gas density switches S1 to Sn to obtain the capacitance value CA corresponding to the failure point. Thereby, the monitoring and locating of the failure point can be performed from the capacitance value CA itself.

Further, as shown in the equation (6), the detected capacitance value CAi from the latest total capacitance value CAo which is constantly measured.
Since the failure point is located based on the change rate of the above, it is possible to realize a highly reliable failure point location that compensates for the average temperature characteristics of the respective capacitance values Ca of the capacitors C0 to Cn.

Embodiment 4 In the third embodiment, the fault point is located using the loop circuit PC in which a plurality of capacitors C1 to Cn are connected in series. However, the fault point is located using a network circuit in which a plurality of capacitors are connected in parallel. Is also good.

Hereinafter, a fourth embodiment of the present invention using a capacitor network circuit will be described with reference to the drawings. FIG. 4 is a configuration diagram showing a fourth embodiment of the present invention.
In the above, Sb1 to Sbn are the above-mentioned gas density switches S
1 to Sn, C1 to Cn, 5C and 11
Are the same as those described above (see FIG. 3).

In this case, a plurality of capacitors C1 to Cn arranged along GIS1 are connected in parallel with each other to form a network circuit NTC. Further, the gas density switches Sb1 to Sbn are formed of normally closed b contacts, and are inserted differently between one ends of adjacent capacitors in the network circuit NTC.

Each of the gas density switches Sb1 to Sbn and each of the capacitors C1 to Cn are connected to each gas section G in the GIS1.
1 to Gn, each pair of gas density switches S
bi and capacitor Ci (i = 1 to n),
Form an n-stage network.

Next, the operation of the fourth embodiment of the present invention shown in FIG. 4 will be described. Normally, gas density switch S
When b1 to Sbn are not turned off, the capacitance value CAo of the entire network circuit NTC detected by the capacitance meter 11 is expressed by the following equation (8).

CAo = Ca × n (8)

In the equation (8), Ca represents each capacitor C
1 to Cn. Here, when a ground fault occurs in the i-th gas section Gi and the gas density switch Sbi is turned off, the capacitance value CAi detected by the capacitance meter 11 is expressed by the following equation (9). Is represented.

CAi = Ca × (i−1) (9)

Therefore, the fault point locating circuit 5C can specify the position i of the gas density switch Sbi that has been turned off by the following equation (10) from the above equations (4) and (5).

I = CAi / CAo × n + 1 (10)

The total capacitance value CAo in the equation (10)
As described above, by using the latest measured values when the gas density switches Sb1 to Sbn are not operated, the temperature characteristics and average aging can be offset as described above.

That is, if the total capacitance value β · CAo and the detected capacitance value β · CAi in consideration of the capacitance change coefficient β are used, the expression (10) becomes the following expression (11), It can be seen that the orientation result of the point i is not affected by the change in the capacitance value.

I = {βCAi / (βCAo)} × n + 1 (11)

As described above, the gas divisions G1 to G of GIS1
The capacitors C1 to Cn corresponding to each n are arranged in a parallel network, and the b-contact gas density switches Sb1 to Sb
By opening one end of each of the capacitors C1 to Cn via n and obtaining the capacitance value CA corresponding to the failure point, it is possible to monitor and locate the failure point from the capacitance value CA itself.

Further, as shown in equation (10), the detected capacitance value CAi from the total capacitance value CAo consisting of the latest measured values is obtained.
Since the failure point is located from the change rate of the above, it is possible to realize a highly reliable failure point location that compensates for the average temperature characteristic of each capacitance value Ca of the capacitors C1 to Cn.

Embodiment 5 In the third and fourth embodiments, the fault point is located using the capacitance value CA of the circuit including the capacitors C1 to Cn corresponding to the respective gas sections G1 to Gn. The fault point may be located using the inductance value.

Hereinafter, a fifth embodiment of the present invention using a loop circuit composed of a plurality of reactors connected in series will be described with reference to the drawings. FIG. 5 is a block diagram showing a fifth embodiment of the present invention. In FIG. 5, 5D corresponds to the fault point locating circuit 5C described above (see FIG. 3), and S1 to Sn
Is the same as described above.

L1 to Ln are a plurality of reactors arranged along GIS1 (see FIG. 11) and connected in series with each other, and together with reactor L0 inserted at the end, constitute a loop circuit PL. .

Each of the reactors L1 to Ln corresponds to each of the gas sections G1 to Gn of the GIS 1, and each of the reactors L1 to Ln.
Each of the gas density switches S1 to Sn is individually and sequentially connected to one end of Ln.

That is, one end of each of the gas density switches S1 to Sn is connected to a different connection point of each of the adjacent reactors in the loop circuit PL.
To Sn are connected to a common end of the loop circuit PL. Thereby, the reactor Li and the gas density switch contact Si (i = 1 to 1) corresponding to each gas section Gi.
n) forms an inverted L-shaped multistage network.

Numeral 12 denotes an inductance meter connected between both open ends of the loop circuit PL, which detects the inductance value LA of the loop circuit PL networked with the gas density switches S1 to Sn. The fault point locating circuit 5D monitors and locates a fault point based on a change in the inductance value LA detected by the inductance meter 12.

Next, the operation of the fifth embodiment of the present invention shown in FIG. 5 will be described. Normally, gas density switch S
1 to Sn are not operating, the inductance meter 12
The overall inductance value LAo of the loop circuit PL detected by the following equation is expressed by the following equation (12).

LAo = La × (n + 1) (12)

In the equation (12), La is the inductance value of one of the reactors L0 to Ln, and is equal to each other. Here, when the i-th gas density switch Si is turned on, the inductance value LAi detected by the inductance meter 12 is represented by the following equation (13).

LAi = La × i (13)

Therefore, the fault point locating circuit 5D can specify the position i of the gas density switch Si that has been turned on by the following equation (14) from the above equations (12) and (13).

I = LAi / LAo × (n + 1) (14)

As the total inductance value LAo in the equation (14), the latest measured value when the gas density switches S1 to Sn are not operated is used to obtain the temperature characteristic and the average aging as described above. Can be offset.

That is, if the total inductance value γ · LAo and the detected inductance value γ · LAi in consideration of the inductance change coefficient γ are used, the equation (14) becomes the following equation (15), and the fault point i is located. It can be seen that the result is not affected by the change in the inductance value.

I = {γ · LAi / (γ · LAo)} × (n + 1) (15)

As described above, the gas divisions G1 to G
By arranging the reactors L1 to Ln corresponding to each n in a series loop, short-circuiting the connection points of the reactors L1 to Ln via the gas density switches S1 to Sn, and obtaining an inductance value LA corresponding to the failure point. The fault point can be monitored and located from the inductance value LA itself.

Further, as shown in equation (14), the latest total inductance value LAo and the detected inductance value LA
Since the failure point is located based on the rate of change from i, a highly reliable failure point location that compensates for the average temperature characteristic of each of the inductance values La of the reactors L0 to Ln can be realized.

Embodiment 6 FIG. In the fifth embodiment, the fault point is located using the loop circuit PL in which the plurality of reactors L1 to Ln are connected in series. However, the fault point is located using a network circuit in which a plurality of LC tank circuits are connected in parallel. May be.

Hereinafter, a sixth embodiment of the present invention using an LC tank circuit network circuit will be described with reference to the drawings. FIG. 6 is a block diagram showing a sixth embodiment of the present invention. In FIG. 6, reference numeral 5E denotes the above-described fault point locating circuits 5A to 5A.
5D, C1 to Cn, L1 to Ln and S
1 to Sn are the same as described above.

In this case, each of the gas sections G1 to G
n corresponding to the capacitor Ci and the reactor Li (i
= 1 to n) are connected in parallel to each other to form a tank circuit Ti, and the tank circuits Ti are connected in parallel to each other to form a network circuit NTT.

Each of the LC tank circuits T1 to Tn is designed to have a different resonance frequency. Therefore, the capacitors Ci constituting each LC tank circuit Ti
In the reactor Li, at least one of the capacitance value Cai of the capacitor Ci and the inductance value Lai of the reactor Li is individually different.

Further, each gas density switch Si (i = 1 to n) is individually connected in series to each tank circuit Ti, and the network circuit NTT is connected to the gas density switch S
When any one of 1 to Sn is turned on, an impedance characteristic corresponding to one of the resonance frequencies of the LC tank circuits T1 to Tn is exhibited. That is, the impedance value becomes almost infinite at a specific resonance frequency.

An impedance meter 13 is connected between both open ends of the network circuit NTT, and detects an impedance value ZA (frequency characteristic) of the network circuit NTT.

The fault point locating circuit 5E monitors the frequency characteristic of the impedance value ZA detected by the impedance meter 13, and locates a fault point based on a change in the impedance value ZA. Further, it is assumed that the fault point locating circuit 5E stores the specific frequency fi corresponding to the resonance frequency of each tank circuit Ti (i = 1 to n) as table data.

FIGS. 7 and 8 are characteristic diagrams showing the frequency characteristics of the impedance value ZA detected by the impedance meter 13, wherein the horizontal axis represents the frequency f and the vertical axis represents the impedance value ZA. FIG. 7 shows a normal state (gas density switch S1).
FIG. 8 is a characteristic diagram when a failure occurs (any of the gas density switches Si is on).

Next, the operation of the sixth embodiment of the present invention shown in FIG. 6 will be described with reference to FIG. 7 and FIG. Normally, when the gas density switches S1 to Sn are not turned on, none of the LC tank circuits T1 to Tn are connected, so that the entire impedance value ZAo of the network circuit NTT detected by the impedance meter 13 is detected.
Becomes almost infinite (see FIG. 7).

Here, when the i-th gas density switch Si is turned on, only the tank circuit Ti corresponding to the gas density switch Si is connected.
As shown in FIG. 8, the characteristic of the impedance value ZA of the TT shows a maximum value (almost infinite) at the specific frequency fi.

At this time, the specific frequency fi corresponds to the resonance frequency of the tank circuit Ti, and is determined by the inductance value Lai of the reactor Li and the capacitance value Cai of the capacitor Ci. Given by

Fi = 1 / {2π} (Lai × Cai} (16)

As a result, the fault point locating circuit 5E generates the characteristic frequency fi corresponding to each tank circuit Ti (i = 1 to n).
Thus, it can be determined which of the gas density switches S1 to Sn has been turned on.

As described above, the LC tank circuits T1 to Tn having different resonance frequencies are provided corresponding to the respective gas sections G1 to Gn, and are line-connected via the respective gas density switches S1 to Sn. By obtaining the impedance value ZA, the fault point can be monitored and located from the impedance value ZA.

Even if a plurality of fault points occur, the fault point locating circuit 5E searches for a local maximum in a predetermined frequency range with respect to the detected impedance value ZA.
A plurality of fault points can be located from a specific frequency indicating each local maximum point.

Embodiment 7 FIG. In the sixth embodiment, the network circuit NTT in which the plurality of tank circuits T1 to Tn are connected in parallel is used, but a network circuit in which a plurality of oscillation circuits are connected in parallel may be used.

A seventh embodiment of the present invention using a network circuit of an oscillation circuit will be described below with reference to the drawings. FIG.
7 is a block diagram showing a seventh embodiment of the present invention. In FIG. 7, reference numeral 5F denotes a fault point locating circuit 5E described above (see FIG. 6).
And S1 to Sn are the same as described above.

H1 to Hn are oscillation circuits arranged along the GIS1 so as to correspond to the respective gas sections G1 to Gn, and are connected in parallel with each other to form a network circuit NTH. Each of the oscillating circuits H1 to Hn is designed to have a different oscillating frequency.

Each of the oscillation circuits Hi is individually connected in series with each of the gas density switches Si (i = 1 to n).
To Sn when the oscillation circuit H1 is turned on.
To Hn.

Reference numeral 14 denotes a DC power supply for supplying power to each of the oscillation circuits H1 to Hn via each of the gas density switches S1 to Sn. The anode is connected to one end of the network circuit NTH, and the cathode (ground) is grounded. ing.

15 is a spectrum analyzer for detecting the oscillation frequency value fA of the network circuit NTH, CX is a DC blocking capacitor inserted between one end of the network circuit NTH and the spectrum analyzer 15, LX
Is a high-frequency blocking reactor inserted between one end of the network circuit NTH and the power supply 14.

The fault point locating circuit 5F includes the oscillation circuits H1 to H1.
The spectrum characteristic corresponding to the oscillation frequency of Hn is stored as table data, and the fault point is located based on the spectrum change of the oscillation frequency value fA.

Next, the operation of the seventh embodiment of the present invention shown in FIG. 9 will be described. Normally, gas density switch S
When 1 to Sn are not on, any oscillation circuit H1
To Hn, the DC voltage from the power supply 14 is not applied, and the output of each of the oscillation circuits H1 to Hn cannot be obtained. Therefore, the spectrum analyzer 15 does not detect the oscillation frequency value fA.

Here, when the i-th gas density switch Si is turned on, the corresponding oscillation circuit Hi starts the oscillation operation by the power supply from the power supply 14 via the reactor LX, and changes the oscillation frequency to the DC blocking. The signal is input to the spectrum analyzer 15 via the capacitor CX.

The spectrum analyzer 15 detects a specific oscillation frequency value fA, and based on the spectrum change of the oscillation frequency value fA, the failure point locating circuit 5F determines which of the gas density switches S1 to Sn has been turned on. Is standardized.

As described above, the oscillating circuits H1 to Hn having different oscillating frequencies are provided corresponding to the respective gas sections G1 to Gn.
By operating via each of the gas density switches S1 to Sn and obtaining the oscillation frequency value fA corresponding to the failure point, it is possible to monitor and locate the failure point based on the spectrum change of the oscillation frequency value fA.

When two or more of the gas density switches S1 to Sn operate simultaneously, the oscillation frequencies of the corresponding oscillation circuits H1 to Hn are different, so that the spectrum analyzer 15 can simultaneously detect them. ,
The fault point locating circuit 5F can locate a plurality of fault points from the frequency spectrum obtained by the spectrum analyzer 15.

Embodiment 8 FIG. In the above-described seventh embodiment, when each of the oscillation circuits H1 to Hn fails, it cannot be self-diagnosed.
Hn may be forcibly operated to perform a self-diagnosis of the soundness of the entire apparatus.

An eighth embodiment of the present invention in which a self-diagnosis of a device including the oscillation circuits H1 to Hn and the spectrum analyzer 15 will be described below with reference to the drawings. FIG. 10 is a block diagram showing an eighth embodiment of the present invention. In FIG. 8, 5G corresponds to the fault point locating circuit 5F described above (see FIG. 9), and includes 14, 15, CX, LX, and H1. ~ Hn,
S1 to Sn and NTH are the same as described above.

D1 to Dn are the respective gas density switches S1 to S
n are individually connected in parallel to the
Is inserted in a polarity opposite to the normal power supply polarity. Numeral 16 denotes a polarity inversion means inserted between the power supply 14 and the network circuit NTH. The polarity inversion means 16 responds to the diagnosis command signal Y from the fault point locating circuit 5G at predetermined intervals.
, The power supply polarity to the network circuit NTH is temporarily inverted.

That is, the polarity inversion means 16 is
Output polarity during normal fault monitoring,
Dn is set to the reverse polarity with respect to the forward direction, and the oscillation circuits H1 to
During the self-diagnosis of Hn, the polarity is set to match the forward direction of the diodes D1 to Dn. Therefore, the diode D1
.About.Dn are not conducted during normal times, but are conducted only during diagnosis.

Next, the operation of the eighth embodiment of the present invention shown in FIG. 10 will be described. First, at the time of normal monitoring of the GIS 1, since the fault point locating circuit 5G does not output the diagnosis command signal Y, the polarity reversing means 16 does not execute the reversing operation of the power supply 14, and the positive polarity is connected to one end of the network circuit NTH. Apply voltage.

As described above, when the applied voltage is between the diodes D1 and D1.
When Dn is set in the non-conducting direction, the oscillation circuits H1 to Hn operate only when the gas density switches S1 to Sn are turned on due to the occurrence of a failure, as described above.

On the other hand, when the diagnosis command signal Y is output from the fault point locating circuit 5G during the self-diagnosis, the polarity reversing means 16 performs the reversing operation of the power supply 14 and applies the voltage to one end of the network circuit NTH. The voltage is set in the conduction direction (negative polarity) of the diodes D1 to Dn.

As a result, the network circuit NTH enters the inspection mode, and the power supply voltage is supplied to all the oscillation circuits H1 to Hn in the network circuit NTH via the diodes D1 to Dn.

Therefore, all the oscillation circuits H1 to Hn start oscillating, and the oscillation frequency value fA at this time is obtained.
Is confirmed via the spectrum analyzer 5, the fault locating circuit 5G can perform a self-diagnosis of the entire apparatus including the network circuit NTH and the spectrum analyzer 15.

As described above, each of the gas density switches S1 to S
n are connected in parallel in a direction that does not conduct normally, and the polarity inverting means 16 is periodically operated to forcibly operate all the oscillation circuits H1 to Hn. The soundness of the signal cable and the spectrum analyzer 15 can be self-diagnosed.

In each of the first to eighth embodiments, the GI
Although the case of locating the fault point of S1 has been described as an example,
It is needless to say that the present invention can be applied to other gas insulating devices and has the same effect.

[0150]

As described above, according to the first aspect of the present invention, two resistance wires disposed along the gas insulating device and having one end short-circuited, and the other end between the other ends of the resistance wire. An ohmmeter for detecting the resistance value and a fault point locating circuit for locating the fault point based on the change in the resistance value are provided, and each end of the gas density switch is located at a different position on one of the two resistance wires. And the other end of the gas density switch is connected to the other position of the other of the two resistance wires so as to correspond to the position of each one end. In addition, there is an effect that a fault point locating device that is easy to maintain can be obtained.

According to a second aspect of the present invention, in the first aspect, the failure point locating circuit is configured to determine a ratio between the resistance value detected by the resistance meter and the latest combined resistance value of the two resistance wires. , The failure point is located on the basis of the equation (1), so that there is an effect that a failure point location apparatus that compensates for the average temperature characteristic of the resistance value can be obtained.

According to a third aspect of the present invention, in the first aspect, each connection point of the gas density switch with respect to the resistance line is arranged so as to be located at a position spaced by a power of two, and each detection resistance Since the value is weighted by a power of two, there is an effect that a fault point locating apparatus capable of locating a plurality of fault points from the detected resistance value is obtained.

According to the fourth aspect of the present invention, a plurality of relays are provided along the gas insulating device and individually connected to each gas density switch, and are provided along the gas insulating device. A ladder network consisting of a plurality of resistor pairs, a plurality of relay contacts that are driven by each relay and individually switch the connection state of each resistor pair, a power supply connected to the ladder network, and a current value flowing through the ladder network An ammeter for detection and a fault point locating circuit for locating a fault point based on a change in the current value are provided, and one resistance value of each resistor pair is connected in series to form a loop circuit, and one resistor The other resistor, which has twice the resistance, is connected in parallel through one end of each one of the resistors in the loop circuit, and each relay contact is connected to each of the other resistors during operation of each gas density switch. The other end Since the ammeter is inserted between the common end of the loop circuit and the required wire, only a small amount of wire is required, making it economical and easy to maintain, and a fault point locating device capable of locating multiple fault points. The effect is obtained.

According to a fifth aspect of the present invention, there is provided a loop circuit including a plurality of capacitors arranged along a gas insulating device and connected in series with each other, and a capacitance for detecting a capacitance value of the loop circuit. And a failure point locating circuit for locating a failure point based on a change in capacitance value, wherein one end of the gas density switch is connected to a different connection point of each adjacent capacitor in the loop circuit. Since each other end of the gas density switch was connected to the common end of the loop circuit,
There is an effect that an economical and easy-to-maintain fault locating device can be obtained because only a small amount of wire is required.

According to a sixth aspect of the present invention, in the fifth aspect, the failure point locating circuit is configured to determine the capacitance value detected by the capacitance meter and the latest total capacitance value of the loop circuit. Since the fault point is located based on the ratio,
There is an effect that a fault point locating device that compensates for the average temperature characteristic of the capacitance value can be obtained.

According to a seventh aspect of the present invention, there is provided a network circuit including a plurality of capacitors arranged along a gas insulating device and connected in parallel with each other, and a capacitance for detecting a capacitance value of the network circuit. And a failure point locating circuit for locating a failure point based on a change in the capacitance value.Each gas density switch is a normally closed contact, and is connected between each end of an adjacent capacitor in the network circuit. Since they are inserted differently, only a small amount of wire is required, and there is an effect that an economical and easy-to-maintain fault locating device can be obtained.

Further, according to claim 8 of the present invention, in claim 7, the fault point locating circuit is configured to determine the capacitance value detected by the capacitance meter and the latest total capacitance value of the network circuit. Since the failure point is located based on the ratio, there is an effect that a failure point location apparatus that compensates for the average temperature characteristic of the capacitance value can be obtained.

According to a ninth aspect of the present invention, there is provided a loop circuit including a plurality of reactors arranged along a gas insulating device and connected in series with each other, and an inductance meter for detecting an inductance value of the loop circuit. A failure point locating circuit for locating a failure point based on a change in inductance value, and connecting one end of the gas density switch to a different connection point between adjacent reactors in the loop circuit; Are connected to the common end of the loop circuit, so only a small amount of wire is required.
There is an effect that an economical and easy-to-maintain fault point locating device can be obtained.

According to a tenth aspect of the present invention, in the ninth aspect, the fault locating circuit is based on a ratio between the inductance value detected by the inductance meter and the latest total inductance value of the loop circuit. Since the fault point is located, there is an effect that a fault point location apparatus that compensates for the average temperature characteristic of the inductance value can be obtained.

According to an eleventh aspect of the present invention, there is provided a network circuit comprising a plurality of LC tank circuits arranged along a gas insulating device and connected in parallel with each other, and an impedance detecting circuit for detecting an impedance value of the network circuit. And a failure point locating circuit for locating a failure point based on a change in impedance value. Each LC tank circuit has a different resonance frequency, and each gas density switch is individually connected in series to a different LC tank circuit. connection,
Since the fault point is located from the frequency of the maximum point of the detected impedance value, a small amount of wire is required,
It is economical and easy to maintain, and has the effect of providing a fault point locating device capable of locating a plurality of fault points.

According to a twelfth aspect of the present invention, in the eleventh aspect, the fault point locating circuit locates the fault point based on the specific frequency at which the impedance value has a maximum. There is an effect that a fault point locating device capable of locating a fault point can be obtained.

According to a thirteenth aspect of the present invention, there is provided a network circuit comprising a plurality of oscillating circuits arranged along a gas insulating device and connected in parallel with each other, and a power supply for driving each oscillating circuit. , A spectrum analyzer that detects the oscillation frequency of the network circuit, a DC blocking capacitor inserted between one end of the network circuit and the spectrum analyzer, and a high frequency blocking capacitor inserted between one end of the network circuit and the power supply And a failure point locating circuit for locating a failure point based on a spectrum change of the oscillation frequency value.Each oscillation circuit has an oscillation frequency different from each other, and each gas density switch is individually connected to a different oscillation circuit from each other. Because they are connected in series, a small amount of wire is required, making it economical and easy to maintain. The effect of the number of orientation of the fault point is available fault point locating system can be obtained.

According to a fourteenth aspect of the present invention, in the thirteenth aspect, a diode individually connected in parallel to each gas density switch, and a power supply polarity from the power supply to the network circuit under the control of the fault point locating circuit. Polarity inverting means for inverting the power supply.The polarity inverting means sets the power supply polarity to the reverse polarity with respect to the forward direction of the diode at the time of normal failure monitoring. Since all the oscillating circuits are operated by setting the same polarity, there is an effect that a fault point locating device capable of performing self-diagnosis of the entire device including the oscillating circuit and the spectrum analyzer is obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of the present invention.

FIG. 3 is a configuration diagram showing a third embodiment of the present invention.

FIG. 4 is a configuration diagram showing a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram showing a fifth embodiment of the present invention.

FIG. 6 is a configuration diagram showing a sixth embodiment of the present invention.

FIG. 7 is a characteristic diagram showing impedance characteristics of a network circuit in a normal state according to a sixth embodiment of the present invention.

FIG. 8 is a characteristic diagram showing impedance characteristics of a network circuit at the time of failure according to Embodiment 6 of the present invention.

FIG. 9 is a configuration diagram showing a seventh embodiment of the present invention.

FIG. 10 is a configuration diagram showing an eighth embodiment of the present invention.

FIG. 11 is a configuration diagram showing a conventional failure point locating device.

[Explanation of symbols]

1 GIS (gas insulated equipment), 5A-5G fault locating circuit, 6a, 6b resistance wire, 6c one end of resistance wire, 7
Resistance meter, 10 ammeter, 11 capacity meter, 12 inductance meter, 13 impedance meter, 9, 14 power supply, 1
5 spectrum analyzer, 16 polarity inversion means, C
1 to Cn capacitor, CA capacitance value, CX DC blocking capacitor, D1 to Dn diode, fi
Specific frequency (resonant frequency), G1 to Gn gas classification, H
1 to Hn oscillation circuit, IA current value, L1 to Ln reactor, LA inductance value, LX High frequency blocking reactor, NT ladder network, NTC, N
TH, NTT network circuit, PC, PL loop circuit, P1-Pn relay, Q1-Qn relay contact,
RA resistance value, r1 to rn, R1 to Rn resistor, S1
To Sn, Sb1 to Sbn Gas density switch, T1 to T
n LC tank circuit, Y diagnostic command signal, ZA impedance value.

Claims (14)

[Claims] 1. A failure point for individually locating a gas density switch in each gas section of a gas-insulated device and locating a failure point in the gas-insulated device based on an operation state of each of the gas density switches. In the locating device, two resistance wires disposed along the gas insulation device and having one end short-circuited; an ohmmeter for detecting a resistance value between the other ends of the resistance wires; A fault point locating circuit for locating the fault point based on a change, wherein one end of each of the gas density switches is connected to a different position of one of the two resistance wires; The other end of the two resistance wires is connected to different positions of the other ends of the two resistance wires so as to correspond to the positions of the one ends. 2. The fault point locating circuit is configured to locate the fault point based on a ratio between a resistance value detected by the resistance meter and a latest combined resistance value of the two resistance lines. The fault point locating device according to claim 1, wherein: 3. The fault point locating apparatus according to claim 1, wherein each connection point of the gas density switch with respect to the resistance wire is arranged at a position spaced apart by a power of two. 4. A failure point in which a gas density switch is individually arranged in each gas section of the gas insulated equipment, and a failure point in the gas insulated equipment is located based on an operation state of each of the gas density switches. In the locating device, a ladder including a plurality of relays disposed along the gas insulating device and individually connected to the respective gas density switches, and a plurality of resistor pairs disposed along the gas insulating device. A network, a plurality of relay contacts driven by each of the relays and individually switching a connection state of each of the resistor pairs, a power supply connected to the ladder network, and an ammeter for detecting a current value flowing through the ladder network And a fault point locating circuit for locating the fault point based on the change in the current value, wherein one resistance value of each of the resistor pairs is connected in series with each other. Forming a loop circuit, the other resistor of each of the resistor pairs has twice the resistance of the one resistor, and is connected in parallel in the loop circuit via one end of each of the one resistor Connected, wherein each of the relay contacts inserts the ammeter between the other end of the other resistor and a common end of the loop circuit when the respective gas density switches operate. Point location device. 5. A failure point in which a gas density switch is individually arranged in each gas section of the gas insulated equipment, and a fault point in the gas insulated equipment is located based on an operation state of each of the gas density switches. In the orientation device, a loop circuit including a plurality of capacitors arranged along the gas insulating device and connected in series to each other, a capacitance meter for detecting a capacitance value of the loop circuit, A failure point locating circuit for locating the failure point based on a change, wherein each one end of the gas density switch is connected to a different connection point of each adjacent capacitor in the loop circuit; and The other end of each of the above is connected to a common end of the loop circuit. 6. The fault point locating circuit locates the fault point based on a ratio between a capacitance value detected by the capacitance meter and a latest total capacitance value of the loop circuit. The fault locating device according to claim 5, characterized in that: 7. A failure point in which a gas density switch is individually arranged in each gas section of the gas insulated equipment, and a failure point in the gas insulated equipment is located based on an operation state of each of the gas density switches. In the locating device, a network circuit including a plurality of capacitors arranged along the gas insulating device and connected in parallel with each other; a capacitance meter for detecting a capacitance value of the network circuit; A failure point locating circuit for locating the failure point based on a change, wherein each of the gas density switches comprises a normally-closed contact, and is inserted differently between one ends of adjacent capacitors in the network circuit. A fault point locating device characterized by being performed. 8. The fault point locating circuit locates the failure point based on a ratio between a capacitance value detected by the capacitance meter and a latest total capacitance value of the network circuit. The fault locating device according to claim 7, characterized in that: 9. A fault point in which a gas density switch is individually arranged in each gas section of the gas insulated equipment, and a fault point in the gas insulated equipment is located based on an operation state of each of the gas density switches. In the locating device, based on a change in the inductance value, a loop circuit that is disposed along the gas insulating device and includes a plurality of reactors connected in series with each other, an inductance meter that detects an inductance value of the loop circuit, A fault point locating circuit for locating the fault point, wherein each one end of the gas density switch is connected to a different connection point of each reactor adjacent in the loop circuit, and each other end of the gas density switch. Is connected to a common end of said loop circuit. 10. The fault point locating circuit locates the fault point based on a ratio between an inductance value detected by the inductance meter and a latest total inductance value of the loop circuit. The fault point location device according to claim 9. 11. A fault point for individually locating a gas density switch in each gas section of a gas-insulated device and locating a fault point in the gas-insulated device based on an operation state of each of the gas-density switches. In the locating device, a network circuit including a plurality of LC tank circuits disposed along the gas insulating device and connected in parallel with each other; an impedance meter for detecting an impedance value of the network circuit; A failure point locating circuit for locating the failure point based on the above, wherein each of the LC tank circuits has a different resonance frequency, and each of the gas density switches is individually connected in series to the different one of the LC tank circuits. A fault point locating device, characterized in that: 12. The fault point locating apparatus according to claim 11, wherein the fault point locating circuit locates the fault point based on a specific frequency at which the impedance value indicates a local maximum. 13. A fault point for individually locating a gas density switch in each gas section of a gas-insulated device, and locating a fault point in the gas-insulated device based on an operation state of each of the gas density switches. In the locating device, a network circuit including a plurality of oscillating circuits disposed along the gas insulating device and connected in parallel with each other; a power supply for driving each of the oscillating circuits; and an oscillating frequency value of the network circuit. A spectrum analyzer to detect, a DC blocking capacitor inserted between one end of the network circuit and the spectrum analyzer, and a high frequency blocking reactor inserted between one end of the network circuit and the power supply. A fault point locating circuit that locates the fault point based on a spectrum change of the oscillation frequency value. Each oscillator has a different oscillation frequencies are, each gas density switch, fault point locating system, characterized in that connected in series individually to different said oscillation circuit to each other. 14. A diode individually connected in parallel to each of the gas density switches, and a polarity inverting means for inverting a power supply polarity from the power supply to the network circuit under the control of the fault locating circuit. The polarity reversing means sets the power supply polarity to the reverse polarity with respect to the forward direction of the diode during normal failure monitoring, and sets the polarity to match the forward direction of the diode during self-diagnosis of the oscillation circuit. The failure point locating device according to claim 13, wherein: