JP2011244567A - Fault point locating apparatus and fault point locating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fault point locating apparatus and fault point locating method capable of determining whether an incident is a trouble in a gas zone or a trouble in a system based only on a pressure signal from a gas pressure sensor.SOLUTION: A fault point locating apparatus locates the fault point of a flashover accident occurring in a gas insulated switchgear 10 which has an energized conductor 4 disposed in a metal container 1 thereof and is filled with an insulating gas 5. The fault point locating apparatus comprises gas pressure sensors 11 installed one in each of plural gas zones delimited within the metal container 1 and a signal processing unit 15 which includes a gas pressure measuring unit 13 which measures the pressure within each gas zone based on gas pressure signals 16 from the gas pressure sensors 11 and a determination processing unit 14 which, when a pressure rise value of the pressure measured by the gas pressure measuring unit 13 is larger than a designated set value, determines that a flashover accident has occurred in the gas zone in which the pressure signal was detected.

Description

  The present invention relates to an accident point locating device and an accident point locating method for locating a portion of a flashover accident occurring in a gas insulated switchgear.

  2. Description of the Related Art In recent years, gas insulated switchgears in which a transformer device such as a circuit breaker is housed in a hermetically sealed container and the installation volume is reduced using an insulating gas have become widespread. In this gas insulated switchgear, a high-voltage power conductor, which is a central conductor, is housed in one or three phases inside a cylindrical metal container at a ground potential, and between the metal container and the power conductor. Insulating gas is sealed in the space. In addition, since the power conducting conductor is housed in the metal container in a form supported by the insulating spacer that partitions the inside of the metal container, a plurality of gas compartments partitioned by the insulating spacer are defined in the metal container. It is made.

  By the way, in the gas insulated switchgear, if the insulation performance of the insulation gas is lowered during operation, partial discharge (so-called arc) may occur due to local dielectric breakdown. When this arc is generated, in the gas insulated switchgear that houses the electrical conductors for one phase, a ground fault to the metallic container of the electrical conductors occurs. In addition, in the gas insulated switchgear that houses the three-phase charging conductors, a short-circuiting accident occurs between the different-phase charging conductors in addition to the ground fault of the charging conductor to the metal container. In the present specification, a ground fault and a short circuit accident occurring in the gas compartment are referred to as a gas compartment accident.

  It seems that the accident location where this accident occurred in the gas compartment can be identified by detecting the gas pressure in the circuit breaker and whether or not the gas pressure has increased. In addition to the accident arc generated in the accident, it is also caused by the interrupt arc generated when an accident occurs in the system and the circuit breaker interrupts the accident current. Therefore, it is difficult to determine whether the accident is in the gas compartment or outside the gas compartment by simply detecting the increase in gas pressure.

  As means for solving such a problem, an accident point locating device disclosed in Patent Document 1 below includes a cutoff current measuring unit that measures a cutoff current based on signals from a cutoff current sensor and an auxiliary contact, a gas pressure sensor A gas pressure measurement unit that measures the gas pressure with the pressure signal from the input as the input, and whether the gas pressure rise in the circuit breaker is caused by an accident arc that occurred in an accident in the gas compartment, or the circuit breaker has an accident It is configured to be able to determine whether it is caused by a break arc generated when the current is cut off.

JP-A-5-126896

  However, since the fault location system disclosed in Patent Document 1 requires many sensors such as a gas pressure sensor, a breaking current sensor, and an auxiliary contact, the configuration of the entire apparatus becomes large. was there. In addition, since it is necessary to calculate the amount of increase in gas pressure based on the detected cut-off current or to compare with the pressure signal detected by the gas pressure measuring unit, there is a problem that the apparatus becomes expensive. In addition, when an accident point locating device is attached to an existing gas insulated switchgear, there has been a problem that a power failure may be required to install a breaking current sensor and an auxiliary contact.

  The present invention has been made in view of the above, and it is possible to determine whether an accident in the gas compartment or an accident in the system can be determined only by a pressure signal from the gas pressure sensor. And to obtain an accident point location method.

  In order to solve the above-described problems and achieve the object, the present invention provides an accident point of a flashover accident occurring in a gas-insulated switchgear in which a conductive conductor is disposed in a cylindrical metal container and filled with an insulating gas. An accident point locating device for locating, based on a pressure signal from a pressure detector installed in the gas compartment defined in the metal container, a pressure measuring unit for measuring the pressure in the gas compartment; A determination unit that determines that a flashover accident has occurred in the gas compartment in which the pressure signal is detected when the pressure increase value of the pressure measured by the pressure measurement unit is greater than a predetermined settling value, and the settling value is The operation start command for the circuit breaker installed in the gas compartment is smaller than the lower limit value of the pressure increase value assumed in the period from the occurrence of the flash accident to the extinction of the arc accompanying the occurrence of the flash accident. Of the circuit breaker after being output An arc associated with the cross operation is set to a value greater than the upper pressure increase value assumed in the period until extinguished, characterized.

  According to the present invention, a gas pressure sensor that detects a gas pressure caused by an arc generated in each gas section and outputs it as a gas pressure signal, and an appropriate set value based on the time difference between the accident arc time and the interruption arc time And a signal processing unit having a determination processing unit for determining the presence or absence of an accident in the gas compartment based on the gas pressure signal from the gas pressure sensor, so that only with the pressure signal from the gas pressure sensor There is an effect that it is possible to determine whether the accident is in the gas compartment or in the system.

FIG. 1 is a diagram showing a configuration of an accident point locating apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a relationship between the transition of the gas pressure measured by the gas pressure measuring unit and the gas pressure increase value calculated by the determination processing unit. FIG. 3 is a diagram for explaining a determination operation performed by the determination processing unit.

  Embodiments of an accident point locating device and an accident point locating method according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
FIG. 1 is a diagram showing a configuration of an accident point locating apparatus according to an embodiment of the present invention. The cylindrical metal container 1 is a so-called casing of the gas insulated switchgear 10 and functions as an external conductor at a ground potential. The metal container 1 is filled with an insulating gas 5 for insulating the metal container 1 and the charging conductor 4 and houses various electric devices such as a meter transformer and a current transformer. Yes. In FIG. 1, as an example, a high-voltage electric conductor 4 that is a central conductor disposed in the metal container 1 and a circuit breaker 3 that interrupts an electric current flowing through the electric conductor 4 are shown.

  The electric conductor 4 is supported by an insulating spacer 2 that is installed at predetermined intervals in the longitudinal direction of the metal container 1 and divides the gas space. The metal container 1 is provided with a plurality of gas compartments provided with insulating spacers 2. The electric conductor 4 may be provided for one phase and may be provided for three phases, but FIG. 1 shows the electric conductor 4 for one phase for convenience. Moreover, in FIG. 1, although the gas division which accommodated the circuit breaker 3 is shown only in one place, the circuit breaker 3 shall be installed also in another gas division.

  Further, FIG. 1 shows the gas pressure by detecting the fault arc 6 generated in the gas section, the interrupting arc 7 generated during the interrupting operation of the circuit breaker 3, and the gas pressure caused by the arc generated in each gas section. A gas pressure sensor (pressure detector) 11 that outputs as a signal 16 and a signal processing unit 15 are shown.

  The accident point locating device according to the present embodiment includes the gas pressure sensor 11 and a signal processing unit 15. The signal processing unit 15 mainly includes gas pressure signals 16 from one or a plurality of gas pressure sensors 11. Pressure measurement for measuring the gas pressure value of each gas compartment based on the gas pressure signal converted to the digital signal by the A / D converter 12 And a determination processing unit (determination unit) 14 that determines the presence or absence of an accident in the gas compartment based on the gas pressure value from the gas pressure measurement unit 13.

  Next, the gas pressure value measured by the gas pressure measurement unit 13 and the determination operation of the determination processing unit 14 will be described in detail with reference to FIGS. 2 and 3.

FIG. 2 is a diagram illustrating the relationship between the transition of the gas pressure measured by the gas pressure measuring unit 13 and the gas pressure increase value calculated by the determination processing unit 14. Figure 3 is a diagram for explaining a determination operation performed by the processing unit 14, the relationship between the cutoff and the fault current I _G current I _S and the gas pressure increase value ΔP in FIGS. 3 (a) shows FIG. 3B shows a specific example of the gas pressure increase value.

In the following description, the gas pressure increase value ΔP calculated by the determination processing unit 14 is described with reference to FIG. 2, and then the first gas pressure increase value ΔP ₁ caused by the accident in the gas compartment is used with reference to FIG. 3. And the second gas pressure increase value ΔP ₂ resulting from the shut-off operation will be described.

  FIG. 2 shows the gas pressure value continuously measured by the gas pressure measuring unit 13, and one gas pressure value is the gas pressure of the gas section where the accident occurred, that is, the gas resulting from the accident in the gas section. It is the transition of pressure. The other gas pressure value is the transition of the gas pressure in the section where no accident has occurred, that is, the gas pressure in the gas section where the circuit breaker 3 is not installed.

  Further, FIG. 2 shows a gas pressure value calculation interval and a gas pressure value measurement timing in the determination processing unit 14. The determination processing unit 14 samples the gas pressure value at a constant time interval, and the interval is, for example, 1 second. FIG. 2 shows eight gas pressure values measured in the interval. In the present embodiment, the pressure value calculation interval of the determination processing unit 14 is 1 second, but is not limited to this.

Hereinafter, the transition of the gas pressure in the section where the accident has occurred and the gas pressure increase value ΔP obtained by the determination processing unit 14 will be described. First, before the accident occurs, the gas pressure measurement unit 13 measures a constant gas pressure value. This is because the insulating gas 5 is filled in the gas compartment. Next, when an accident occurs, the gas pressure measuring unit 13 measures a gas pressure value that rises due to the accident. The gas pressure increase value ΔP at this time is caused by the accident arc 6 and is obtained by the determination processing unit 14 and can be expressed by the following calculation formula.
Gas pressure increase value ΔP = P _k −P _m
However, P _k denotes the gas pressure after the occurrence accident within the gas compartment, P _m denotes the gas pressure before the accident in the gas compartment. In FIG. 2, the time difference between the gas pressure _Pk and the gas pressure _Pm is set to, for example, about 7 seconds.

  Here, the arc generated in the gas compartment can be classified into the accident arc 6 and the interruption arc 7 as described above.

When the gas pressure rise value due to the heat of the accident arc 6 is defined as [Delta] P _G, generally, the gas pressure increase value [Delta] P _G is expressed by equation (1).
ΔP _G = C · V _arc · I _G · t _G /V×0.098 (1)
ΔP _G : Pressure increase value (kPa)
C: Coefficient (= 0.6)
V _arc : Arc voltage (V)
I _G : Accident current (A)
t _G : Accident arc time (sec)
V: Tank capacity (liter)
The arc voltage V _arc is a ground fault voltage of the accident arc 6.
The fault current I _G is almost determined by the position on the power system of the substation where the gas-insulated switchgear is installed, and in the case of a one-line ground fault with an ineffective grounding system, the minimum value is I _G = several hundred A Degree.

Accident arcing time t _G is the operating time of the protection relay and the current interruption time of the circuit breaker 3, it is substantially determined. More specifically, for example, when an accident in the gas compartment occurs during operation of the gas insulated switchgear, an accident arc 6 as shown in FIG. 1 occurs. At this time, the current flowing through the current conductor 4 is monitored by a current transformer. When the current value exceeds a predetermined value, a protection relay (not shown) is activated. Then, a CB operation command is output from the protection relay to the circuit breaker 3, the circuit breaker 3 is opened by the CB operation command, and the accident arc 6 is extinguished. The time from when the protection relay operates until the CB operation command is output is about several hundred ms, and the time from when the CB operation command is output until the accident arc 6 is extinguished is several times. It is about 10 ms. Therefore, the accident arcing time t _G is the accident arc 6 from the protective relay is operated is time (hundreds ms) until it is extinguished.

Thus, once the tank volume V of the gas compartment, may be obtained gas pressure increase value [Delta] P _G. In the case of a one-line ground fault of an ineffective grounding system, for example, I _G = several hundred A, t _G = several hundred ms, V _arc = several thousand V (distance d = several cm, electric field strength E = several hundreds V / cm ) Can be set.

If the gas pressure increase value resulting from the heat of the breaking arc 7 is defined as ΔP _ARC , the gas pressure increase value ΔP _ARC is expressed by the following equation (2).
ΔP _ARC = C · V _arc · I _S · t _S /V×0.098 (2)
C: Coefficient (= 0.6)
V _arc : Arc voltage (V)
_IS : Breaking current (A)
t _S : Breaking arc time (sec)
V: Tank capacity (liter)
The arc voltage V _arc is a voltage during the breaking operation of the circuit breaker 3.
The breaking current _IS is a current that flows through the current conductor 4 when the breaker 3 performs a breaking operation.
The interruption arc time t _S is a time (tens of ms) from when the CB operation command is output until the interruption arc 7 disappears.

Thus, once the tank volume V of the gas compartment, as with [Delta] P _G the gas pressure increase value, it is possible to determine the gas pressure increase value [Delta] P _ARC. In the case of a one-line ground fault of an ineffective grounding system, for example, I _S = 0 to several thousand A, t _S = several tens ms, V _arc = several hundreds V (distance d = several cm, electric field strength E = several tens V) / Cm).

Here, when an accident in the gas compartment occurs, the gas pressure detected by the gas pressure sensor 11 is caused not only by the gas pressure caused by the accident arc 6 but also by the breaking arc 7 generated by the breaking operation of the circuit breaker 3. Gas pressure is also included. This breaking operation of the circuit breaker 3 is accompanied by the occurrence of the accident arc 6. That is, when the gas compartment accident occurs, the gas pressure measuring unit 13, not only the gas pressure increase value [Delta] P _G due to P accident arc 6, the gas pressure increase value [Delta] P _ARC resulting from blocking arc 7 is also measured The

This will be described below in association with FIG.
First, when an accident in a gas compartment occurs, the first gas pressure increase value ΔP ₁ in the gas compartment is expressed by the equation (3).
ΔP ₁ = ΔP _G + ΔP _ARC (3)
On the other hand, if an accident occurs outside gas compartment, a second gas pressure increase value [Delta] P ₂ of the gas compartment cutoff arc 7 is generated is expressed by equation (4).
ΔP ₂ = ΔP _ARC (4)

(3) Gas pressure increase value [Delta] P _G contained in the equation is a value obtained by the above-mentioned (1), (3) and (4) Gas pressure increase value [Delta] P _ARC included in expression (2 ) Value obtained by the formula. However, the upper limit value of the gas pressure increase value [Delta] P _ARC tend to be lower than the lower limit value of the gas pressure increase value [Delta] P _G as shown in FIG. 3 (a). This is because the difference between the accident arcing time t _G and blocking arcing time t _s is approximately 20-fold. That is, among the parameters for determining the gas pressure increase value [Delta] P _ARC and the gas pressure increase value [Delta] P _G, because the arcing time _{(t G,} t _s) the difference is more dominant than the other parameter difference.

The lower limit of the gas pressure increase value [Delta] P _G shown in FIG. 3 (a), in the case of clear distinction ground fault ineffective grounding system, the parameters eg _{t G} = several hundred _{ms, V arc} = several thousand V Is a conceptual representation of the gas pressure increase value when the accident current _IG is increased from X (A) to Y (A), for example. Further, the upper limit value of the gas pressure increase value ΔP _ARC shown in FIG. 3A is the same as described above, and the gas pressure increase value when each parameter is set to, for example, t _S = several tens of ms and V _arc = several hundreds V. , which conceptually shows the cutoff current I _s is a value when the increase, for example, from 0 to thousands (a). However, these numerical values are examples, and are not limited to these.

Next, the hatched portion shown on the upper side of FIG. 3A is the value of the first gas pressure increase value ΔP ₁ obtained by the equation (3). Why the entire upper than the lower limit value of the gas pressure increase value [Delta] P _G is shown by oblique lines is as follows. That is, (3) a first gas pressure increase value [Delta] P ₁ obtained by the equation, since the gas pressure increase value [Delta] P _G and the gas pressure increase value [Delta] P _ARC may change the respective parameters described above are not necessarily uniquely determined Because.

Further, the hatched portion shown on the lower side of FIG. 3 (a) is a second value of the gas pressure increase value [Delta] P ₂ obtained in (4) below. The reason why the entirety below the upper limit value of the gas pressure increase value ΔP _ARC is indicated by hatching is as follows. Since the breaking timing of the circuit breaker 3 varies according to the zero point cycle of the alternating current flowing through the charging conductor 4, the upper limit value of the gas pressure increase value ΔP _ARC is, for example, when the breaking arc time t _S = several tens of ms. In the case of a value, the gas pressure increase value ΔP _ARC when the break arc time t _S = several ms is a value lower than the upper limit value of the gas pressure increase value ΔP _ARC shown in FIG.

Figure 3 (b) is a diagram for specifically explaining the relationship between the gas pressure increase value [Delta] P _ARC and the gas pressure increase value [Delta] P _G shown in FIG. 3 (a). A two-dot chain line indicates a gas pressure increase value [Delta] P _ARC when the shut-off arcing time _{t S} = several tens ms, a solid line indicates the gas pressure increase value [Delta] P _G when the accident arcing time _{t G} = several hundred ms. The dashed line is a value obtained by adding the these gas pressure increase value [Delta] P _ARC and the gas pressure increase value [Delta] P _G, a value that the gas pressure increase value [Delta] P _ARC was Jojo the gas pressure increase value [Delta] P _G .

Thus, the lower limit value of the gas pressure increase value [Delta] P _G, since there is a tendency to be higher than the upper limit value of the gas pressure increase value [Delta] P _ARC, the lower limit value and the gas pressure increase value [Delta] P _ARC gas pressure increase value [Delta] P _G As shown in FIG. 3A, there is a region that does not belong to any region (shaded area) between the upper limit value and the gas pressure increase value ΔP in that region may be a uniquely determined value. Recognize.

In other words, the gas pressure increase value ΔP in that region is determined by the period from the time of the flash accident to the extinction of the arc associated with the occurrence of the flash accident (accident arc time t _G ) and the conducting conductor when the flash accident occurs. in the arc voltage V _arc applied, smaller than the lower limit of the pressure increase value [Delta] P _G is calculated based on the fault current I _G flowing through the current conductor during flashover accident, and blocked installed in the gas compartment A period from when an operation start command to the circuit breaker 3 is output until the arc associated with the circuit breaker 3 is extinguished (breaking arc time t _s ), an arc voltage V _arc during the circuit breaker 3 breaking operation, breaker 3 is the upper limit value greater than the gas pressure increase value [Delta] P _aRC which is calculated based on the breaking current (arc current) I _s when the cutoff operation.

Fault point locating system according to the present embodiment is smaller than the lower limit value of the pressure increase value [Delta] P _G, and, using a large gas pressure increase value [Delta] P than the upper limit value of the gas pressure increase value [Delta] P _ARC (set value [Delta] P ₀₎ Thus, it is configured to determine whether the gas compartment accident or the gas compartment accident. For example, an appropriate settling value ΔP ₀ is set in the determination processing unit 14 as shown in FIG.

When the cut-off current _IS is a predetermined current value I ₀ (for example, several thousand A) or less, between the set value ΔP ₀ , the first gas pressure increase value ΔP _1, and the second gas pressure increase value ΔP ₂ Has the following relationship.
ΔP ₁ > ΔP ₀ > ΔP ₂
Therefore, the determination processing unit 14 can determine that an accident in the gas compartment has occurred in the gas compartment where the gas pressure increase value ΔP higher than the set value ΔP ₀ is detected.

In general, in the case of a gas insulated switchgear of a low voltage class (for example, rated voltage 22 kV to 154 kV) in a non-effective grounding system (the fault current is suppressed by grounding the neutral point of the system through a resistor or the like). Although the cut-off current I _S rarely exceeds a predetermined current value I ₀ (for example, several thousand A), when the cut-off current I _S exceeds the predetermined current value I ₀ , the set value ΔP ₀ And the second gas pressure increase value ΔP ₂ have the following relationship.
ΔP ₂ > ΔP ₀
Thus, in rare cases, the gas pressure increase value ΔP ₂ may exceed the settling value ΔP ₀ . Therefore, there is a probability that the determination processing unit 14 determines that an accident in the gas compartment has occurred in a plurality of compartments including normal compartments in which no accident in the gas compartment has occurred. However, even when the determination processing unit 14 makes the determination as described above, the number of compartments thus judged is sufficiently small compared to the total number of compartments, and therefore the compartments where the gas compartment accident has occurred are narrowed down. Is easy, and such a determination does not prevent quick accident recovery.

Next, the operation will be described.
The gas pressure sensor 11 monitors the gas pressure in each gas section divided by the spacer 2, and the gas pressure detected by the gas pressure sensor 11 is converted into an A / D converter as a gas pressure signal 16 (analog). 12 is taken in. The gas pressure signal 16 taken into the A / D converter 12 is converted into a digital signal by the A / D converter 12 and output to the gas pressure measuring unit 13. The gas pressure measurement unit 13 constantly measures the gas pressure value of each gas section based on the gas pressure signal from the A / D converter 12, and the gas pressure value measured by the gas pressure measurement unit 13 is: It is taken into the determination processing unit 14. In the determination processing unit 14, as shown in FIG. 2, there samples the pressure at a predetermined time interval, the pressure P _m to m seconds has been measured before the pressure P _k and the pressure P _k which is measured at a certain time Based on this, a gas pressure increase value ΔP is calculated.

Here, in the gas compartment of an accident in the gas compartment is generated, by the energy of incident arc 6, since the gas pressure as shown in FIG. 2 rises, the determination processing section 14 (1) of the gas pressure increase value [Delta] P _G A gas pressure increase value ΔP corresponding to is calculated. Since the calculated gas pressure increase value ΔP is higher than the set value ΔP ₀ as described with reference to FIG. 3, the determination processing unit 14 uses the gas section in the gas section where the gas pressure increase value ΔP is detected. It can be determined that an internal accident has occurred.

On the other hand, when an accident occurs outside the gas compartment, the gas pressure increases due to the energy of the break arc 7 in the gas compartment where the break arc 7 is generated. The determination processing unit 14 calculates a gas pressure increase value ΔP corresponding to the gas pressure increase value ΔP _ARC in equation (2). Since the gas pressure increase value ΔP is lower than the set value ΔP ₀ as described with reference to FIG. 3, the determination processing unit 14 causes the gas compartment where the gas pressure increase value ΔP is detected to have an accident in the gas compartment. It can be determined that it has not occurred.

As described above, the accident point locating device according to the present embodiment includes the gas pressure sensor 11 that detects the gas pressure caused by the arc generated in each gas section and outputs it as the gas pressure signal 16, and the accident. A determination processing unit 14 that sets an appropriate set value ΔP ₀ based on the time difference between the arc time t _G and the interruption arc time t _S and determines whether there is an accident in the gas compartment based on the gas pressure signal 16 from the gas pressure sensor 11. Therefore, it is possible to determine whether the accident is inside the gas compartment or outside the gas compartment by using only the gas pressure sensor 11 without using a plurality of types of sensors such as a current sensor. It becomes possible to judge. The conventional technology not only requires the costs associated with the installation and renovation of multiple types of sensors, but also has the problem that the refurbishment of software becomes large in order to properly measure gas pressure due to the large number of types of sensors. there were. According to the accident point locating apparatus according to the present embodiment, only the gas pressure sensor 11 needs to be used, so that the installation of the sensor is easy and the scale of software modification is minimized. It is possible to determine with a simple device configuration.

  As described above, the present invention can be applied to an accident point locating device and an accident point locating method for identifying an accident site of a flashover accident occurring in a gas insulated switchgear, and in particular, only a pressure signal from a gas pressure sensor. Therefore, it is useful as an invention that can determine whether the accident is in the gas compartment or the system.

DESCRIPTION OF SYMBOLS 1 Metal container 2 Insulating spacer 3 Circuit breaker 4 Electrical conductor 5 Insulating gas 6 Accident arc 7 Breaking arc 10 Gas insulated switchgear 11 Gas pressure sensor (pressure detector)
12 A / D converter 13 Gas pressure measurement unit 14 Determination processing unit (determination unit)
15 signal processor 16 the gas pressure signal I _G fault current I _S breaking current [Delta] P gas pressure increase value [Delta] P ₀ set value [Delta] P ₁ a first gas pressure increase value [Delta] P ₂ second gas pressure increase value P _k gas compartment accident after the gas pressure P _m gas compartment accident before the gas pressure [Delta] P _aRC cutoff arc energy by gas pressure increase value [Delta] P _G accidents arc energy by gas pressure rise value of

Claims (6)

An accident point locating device for locating an accident point of a flashover accident occurring in a gas insulated switchgear in which a conducting conductor is arranged in a cylindrical metal container and filled with an insulating gas,
A pressure measurement unit that measures the pressure in the gas compartment based on a pressure signal from a pressure detector installed in the gas compartment defined in the metal container;
A determination unit that determines that a flashover accident has occurred in the gas section in which the pressure signal is detected when the pressure increase value of the pressure measured by the pressure measurement unit is greater than a predetermined settling value;
With
The set value is smaller than a lower limit value of a pressure increase value assumed in a period from the occurrence of a flashover accident to the extinction of an arc accompanying the occurrence of a flashover accident, and for the breaker installed in the gas compartment Accident point characterized in that it is set to a value larger than the upper limit value of the pressure increase value assumed in the period from the output of the operation start command to the extinction of the arc associated with the circuit breaker operation. Orientation device.   The set value flows from the time of the flash accident until the arc associated with the occurrence of the flash accident extinguishes, the voltage applied to the conducting conductor at the time of the flash accident, and the flowing conductor at the time of the flash accident. The arc associated with the breaking operation of the circuit breaker is extinguished after the operation start command for the circuit breaker installed in the gas compartment is output, which is smaller than the lower limit value of the pressure increase value calculated based on the current. The pressure is set to a value greater than the upper limit value of the pressure increase value calculated based on the period up to, the arc voltage during the breaking operation, and the arc current during the breaking operation. The accident location system described.   3. The determination unit according to claim 1, wherein when the pressure increase value is smaller than the set value, the determination unit determines that a flashover accident has not occurred in the gas section in which the pressure signal is detected. Accident point locator. An accident point locating method applicable to an accident point locating device for locating an accident point of a flashover accident occurring in a gas insulated switchgear in which a conducting conductor is arranged in a cylindrical metal container and filled with an insulating gas,
A pressure signal receiving step of receiving a pressure signal from a pressure detector installed in a gas compartment defined in the metal container;
A pressure measuring step for measuring the pressure in the gas compartment based on the pressure signal;
A pressure value calculating step for calculating the pressure value of the pressure measured in the pressure measuring step at a predetermined timing;
A pressure increase value calculating step for calculating a pressure increase value based on the pressure value calculated in the pressure value calculating step;
An operation start command is output for the circuit breaker installed in the gas compartment that is smaller than the lower limit of the assumed pressure rise value during the period from the time of the flash accident to the extinction of the arc associated with the occurrence of the flash accident. A settling value larger than the upper limit value of the pressure rise value assumed in the period from when the arc accompanying the breaking operation of the breaker is extinguished, and the pressure rise value calculated in the pressure rise value calculation step Comparing steps,
Accident point location method characterized by including. An accident point locating method applicable to an accident point locating device for locating an accident point of a flashover accident occurring in a gas insulated switchgear in which a conducting conductor is arranged in a cylindrical metal container and filled with an insulating gas,
A pressure signal receiving step of receiving a pressure signal from a pressure detector installed in a gas compartment defined in the metal container;
A pressure measuring step for measuring the pressure in the gas compartment based on the pressure signal;
A pressure value calculating step for calculating the pressure value of the pressure measured in the pressure measuring step at a predetermined timing;
A pressure increase value calculating step for calculating a pressure increase value based on the pressure value calculated in the pressure value calculating step;
Based on the period from the time of the flash accident to the extinction of the arc associated with the occurrence of the flash accident, the voltage applied to the conducting conductor at the time of the flash accident, and the current flowing through the conducting conductor at the time of the flash accident A period from the time when the operation start command for the circuit breaker installed in the gas section is output to the time when the arc associated with the circuit breaker is extinguished is smaller than the lower limit value of the calculated pressure increase value; A settling value larger than the upper limit value of the pressure increase value calculated based on the arc voltage during the interruption operation and the arc current during the interruption operation, and the pressure increase value calculated in the pressure increase value calculation step. A comparison step to compare;
Accident point location method characterized by including.   The comparison step determines that a flashing accident has occurred in the gas section where the pressure signal is detected when the pressure increase value calculated in the pressure increase value calculation step is greater than the set value, and calculates the pressure increase value 5. The method according to claim 4, further comprising a determination step of determining that a flashover accident has not occurred in the gas section where the pressure signal is detected when the pressure increase value calculated in the step is smaller than the set value. 5. Accident point location method described in 5.

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