JP2021092498A - Ground fault point locating system, ground fault point locating device, locating method of ground fault point locating device, program - Google Patents

Abstract

To highly accurately locate a ground fault point when a ground fault accident occurs in a distribution system composed of distribution lines including branch points such as T-shaped or cross-shaped branches.SOLUTION: A ground fault point locating system is provided, including a plurality of measurement terminals installed across a branch point on a distribution line that includes a branch and a ground fault point locating device 500 communicably connected to the plurality of measurement terminals. When a ground fault accident occurs in the distribution line, the plurality of measurement terminals transmit, to the ground fault point locating device, information in which zero-phase current and zero-phase voltage are correlated with the current time, and the ground fault point locating device locates a ground fault point of the distribution line on the basis of the information transmitted from a combination of two of the measurement terminals out of three or more of the measurement terminals installed across the branch point and a surge propagation speed. The ground fault point locating device comprises a determination unit that determines whether the ground fault point exists inside a prescribed region centering on the branch point of the distribution line.SELECTED DRAWING: Figure 5

Description

The present invention relates to a ground fault point locating system, a ground fault point locating device, a ground fault point locating device locating method, and a program.

For example, when a ground fault occurs in a distribution line, a ground fault point setting system is known that determines the position of the ground fault in the distribution line (see, for example, Patent Document 1).

This ground fault point locating system includes a current sensor that detects a current flowing through a distribution line, a voltage sensor that detects a voltage that appears on the distribution line, a measuring terminal, and a ground fault point locating device. The current sensor, the voltage sensor, and the measuring terminal are arranged on a support column on which a distribution line is erected, and the ground fault point locating device is arranged in a building such as an electric power company. Then, the plurality of measuring terminals transmit the information indicating the zero-phase current and the zero-phase voltage obtained from the current sensor and the voltage sensor to the ground fault point determining device in association with the information indicating the current time obtained from the GPS satellite. To do. On the other hand, the ground fault point locating device defines the ground fault point by performing a predetermined calculation based on the information indicating the zero-phase current and the zero-phase voltage and the information indicating the current time obtained from a plurality of measuring terminals.

Japanese Unexamined Patent Publication No. 2004-132762

Distribution lines (for example, 6kV distribution system) include a straight distribution line (trunk line) and a distribution line (branch line) that branches from an arbitrary position on this distribution line into a dendritic shape (T-shaped, cross-shaped, etc.). , May be included.

However, the ground fault point locating system described in Patent Document 1 is a system for locating a ground fault point when a ground fault occurs in a distribution system composed of linear distribution lines, and is linear and dendritic. There is a problem that it is not possible to accurately determine the ground fault point when a ground fault occurs in the distribution system consisting of the distribution lines of.

Therefore, the present invention is a ground fault point locating system capable of accurately locating a ground fault point when a ground fault occurs in a distribution system composed of distribution lines including branch points such as a T-shaped branch or a cross branch. , A ground fault point locating device, a ground fault point locating device locating method, and a program.

The main invention that solves the above-mentioned problems includes a plurality of measuring terminals installed on a distribution line including a branch with a branch point sandwiched between them, a ground fault locating device that is communicably connected to the plurality of measuring terminals. The plurality of measuring terminals are configured to include, and information indicating a zero-phase current and a zero-phase voltage output from a sensor that detects the current and voltage of the distribution line when a ground fault occurs in the distribution line. The information associated with the information indicating the current time is transmitted to the ground fault point locating device, and the ground fault point locating device is among the three or more measurement terminals installed across the branch point. A ground fault point determination system that defines the ground fault point of the distribution line based on the information transmitted from the combination of any two of the measurement terminals and the surge propagation velocity, and is the ground fault point. The locating device includes a discriminating unit that determines whether or not the ground fault point exists inside a predetermined area centered on the branch point of the distribution line.
Other features of the invention will become apparent with reference to the accompanying drawings and the description herein.

According to the present invention, it is possible to accurately localize a ground fault point when a ground fault occurs in a distribution system composed of distribution lines including branch points such as a T-shaped branch and a cross branch.

It is a block diagram which shows the ground fault point setting system which concerns on this embodiment. It is a schematic diagram which shows that a plurality of measurement terminals are installed along a linear distribution line so as to sandwich a ground fault point. It is a schematic diagram which shows that three measurement terminals are installed with respect to the distribution line including a T-shaped branch. It is a schematic diagram which shows that four measurement terminals are installed for the distribution line including a cross branch. It is a block diagram which shows the function of the ground fault point locating apparatus used in the ground fault point locating system which concerns on this embodiment. It is a block diagram which shows the function of the pattern discriminating part which concerns on this embodiment. In this embodiment, it is a figure for demonstrating an example of the diagnosis result stored in the diagnosis result storage part. It is a block diagram which shows the function of the standardization part which concerns on this embodiment. In this embodiment, it is a flowchart which shows an example of the ground fault point setting process which is a software processing operation realized by executing a program by the ground fault point setting apparatus 500. It is a flowchart which shows an example of the pattern discriminating process executed in the ground fault point setting process. It is a flowchart which shows an example of the 1st discriminating process executed in the pattern discriminating process. It is a flowchart which shows an example of the 2nd discriminating process executed in the pattern discriminating process. It is a flowchart which shows an example of the pattern determination process executed in the 2nd determination process. It is a flowchart which shows an example of the locating process executed in the ground fault point locating process. It is a block diagram which shows the function of the standardization part which concerns on the modification. In the modified example, it is a figure which shows the process of the calculation performed by the 4th calculation unit when the arrangement pattern of the ground fault points corresponds to the 2nd pattern.

The description of this specification and the accompanying drawings will clarify at least the following matters.
=== Ground fault point positioning system ===
FIG. 1 is a block diagram showing a ground fault point determination system according to the present embodiment. In addition, in FIG. 1, in order to make the explanation related to the localization of the ground fault point easy to understand, it is assumed that the ground fault point exists at a position sandwiched between the two nearest measuring terminals on the linear distribution line. ..

The ground fault point locating system 100 is a system for locating the position of the distribution line 200 in which the ground fault has occurred when the distribution line 200 has a ground fault.

The ground fault point locating system 100 includes a plurality of current sensors 310, a plurality of voltage sensors 320, a plurality of measuring terminals 400, and a ground fault point locating device 500 as means for locating the ground fault point. ..

Each of the plurality of current sensors 310 is installed on, for example, a support column 600. The current sensor 310 detects the zero-phase current of the distribution line 200 at the installation location of the support column 600 when a ground fault occurs in the distribution line 200. The plurality of voltage sensors 320 are installed, for example, on a support column 600 so as to be adjacent to each of the plurality of current sensors 310. The voltage sensor 320 detects the zero-phase voltage of the distribution line 200 at the installation location of the support column 600 when a ground fault occurs in the distribution line 200. The pair of current sensors 310 and the voltage sensor 320 installed adjacent to the column 600 are, for example, a storage box for the switch 800 installed on the column 600 in order to protect them from external factors (wind, rain, ultraviolet rays, etc.). It shall be housed in 800A in a sealed state.

Each of the plurality of measurement terminals 400 is installed on, for example, a support column 600, and is connected to the ground fault point locating device 500 via wireless communication. Then, the measuring terminal 400 associates the information indicating the zero-phase current obtained from the current sensor 310 and the information indicating the zero-phase voltage obtained from the voltage sensor 320 with the information indicating the current time obtained from the GPS satellite 700. It is transmitted to the ground fault point locating device 500. The measuring terminal 400 may be connected to the ground fault locating device 500 via a wired communication line.

The ground fault point locating device 500 is a device that comprehensively manages a plurality of measurement terminals 400 via wireless communication so that the ground fault point can be located, and is installed in a building such as an electric power company, for example. Has been done. The ground fault point locating device 500 is a zero-phase obtained from two measurement terminals 400 (for example, measurement terminals 400A and 400B) having the shortest distance between installations among the combination of two measurement terminals 400 sandwiching the ground fault point. The ground fault point is determined by performing a predetermined calculation based on the information indicating the current and the zero-phase voltage and the information indicating the current time.

In particular, the ground fault point locating device 500 in the present embodiment includes both a distribution line 200 including only a linear distribution line 200A and a distribution line 200 including a linear distribution line 200A and a dendritic distribution line 200B. It is a device that can accurately determine the ground fault point in the event of a ground fault.
=== Ground fault point determination method ===

Here, an example of a method of defining a ground fault point using two measuring terminals 400A and 400B sandwiching the ground fault point (failure point) will be described. The ground fault point locating device 500 includes the distance on the distribution line 200 between the measurement terminals 400A and 400B, the surge propagation speed, the surge arrival time from the ground fault point to the measurement terminal 400A, and the ground fault point to the measurement terminal 400B. Based on the difference from the surge arrival time, the distance on the distribution line 200 from the ground fault point to the measurement terminal 400A or the measurement terminal 400B is calculated.

である。このように、地絡点標定装置５００は、地絡点から計測端末４００Ａ（又は計測端末４００Ｂ）までの距離ｘを求めることにより、地絡点を標定する。尚、地絡点の具体的な標定手法については例えば特許文献１に開示されているため、その説明を省略する。 Specifically, the ground fault point locating device 500 performs a calculation based on the following equation (1) when calculating the distance x from the ground fault point to the measuring terminal 400A as a locating value.

Is. In this way, the ground fault point locating device 500 determines the ground fault point by obtaining the distance x from the ground fault point to the measurement terminal 400A (or the measurement terminal 400B). Since the specific method for determining the ground fault is disclosed in Patent Document 1, for example, the description thereof will be omitted.

<Positioning of ground fault points using three measuring terminals installed on a linear distribution line>
In the example shown in FIG. 1, the ground fault point is set by the ground fault point setting device 500 using the outputs of the two nearest measuring terminals 400A and 400B installed across the ground fault point. In the equation (1), the surge propagation velocity v is a fixed value, but the larger the error between the value of the surge propagation velocity V used in the equation (1) and the actual surge propagation velocity V, the greater the error in the equation (1). ), The error between the distance x calculated based on) and the actual ground fault point also becomes large.

On the other hand, in the ground fault point locating device 500, in addition to the combination of the measurement terminals 400A and 400B installed across the ground fault point, the combination of two measurement terminals sandwiching the ground fault point but not the immediate vicinity. The output of can be used for localization. Hereinafter, a specific example thereof will be described.

FIG. 2A is a schematic view showing that three measuring terminals are installed along the linear distribution line so as to sandwich the ground fault point.

In FIG. 2A, the two measuring terminals 400A and 400B are installed at the nearest positions sandwiching the ground fault point, as in FIG. The third measuring terminal 400C is installed at a predetermined position on the side opposite to the ground fault point of the measuring terminal 400A. In this case, there are two combinations of the two measuring terminals that sandwich the ground fault point: the measuring terminals 400A and 400B and the measuring terminals 400C and 400B.

In this way, when the ground fault point is defined by using a plurality of combinations consisting of two measurement terminals, the ground fault point locating device 500 has a variation in the distance x (variation in the reference value) calculated by the equation (1). ) Is calculated as the minimum surge propagation velocity v.

である。 Specifically, the standard deviation σ represented by the following equation (2) is used as an evaluation function, and the surge propagation velocity v satisfying the condition dσ / dv = 0 that minimizes the standard deviation σ is set according to the following equation (3). calculate.

Is.

For example, in the example shown in FIG. 2A, the number n = 2 of the combination of the two measuring terminals. Further, in the example shown in FIG. 2A, the ground fault point is located between the measuring terminal 400A and the measuring terminal 400B, and between the measuring terminal 400C and the measuring terminal 400B. At this time, the surge propagation speed v is expressed by the following equation (3-1).

The ground fault point locator 500 performs a calculation based on the equation (3) using two combinations (measurement terminals 400A and 400B and measurement terminals 400C and 400B) consisting of two measurement terminals, and performs a surge propagation velocity. Calculate v.

In general, the range of the surge propagation velocity v at which the ground fault point can be defined is 50 (m / μs) ≦ v ≦ 300 (m / μs). Therefore, when the value of the surge propagation velocity V derived by the calculation based on the equation (3) is a value deviating from the above range, the ground fault point locating device 500 is a value for locating the ground fault point. It is judged that the ground fault point cannot be determined without adopting it.

When the derived value of the surge propagation velocity V is within the above range, the ground fault point locator 500 performs a calculation based on the equation (1) to derive _{two distances x i.} Specifically, the ground fault point locator 500 substitutes the derived surge propagation velocity v into the equation (1), and performs an operation based on the equation (1) for each of the two combinations, so that the two distances x Derivation of _i.

<Location of ground fault points using four measuring terminals installed on a linear distribution line>
FIG. 2B is a schematic view showing that four measuring terminals are installed along the linear distribution line so as to sandwich the ground fault point. In FIG. 2B, the two measuring terminals 400A and 400B are installed at the nearest positions sandwiching the ground fault point, as in FIG. The third measuring terminal 400C is installed at a predetermined position on the side opposite to the ground fault point of the measuring terminal 400A. The fourth measuring terminal 400D is installed at a predetermined position on the side opposite to the ground fault point of the measuring terminal 400B. In this case, there are four combinations of the two measuring terminals that sandwich the ground fault point: the measuring terminals 400A and 400B, the measuring terminals 400C and 400B, the measuring terminals 400C and 400D, and the measuring terminals 400A and 400D. Also in this case, the ground fault point locating device 500 can determine the ground fault point by using the equations (1) to (4) as in the case of using three measuring terminals.

<Location of ground fault points using three measuring terminals installed on distribution lines including branches>
3 (A) and 3 (B) are schematic views showing that three measuring terminals are installed on a distribution line including a T-shaped branch. In the example shown in FIG. 3A, the ground fault point is outside the first area R1 represented by a circle having a radius r1 centered on the branch point, and the measurement terminal 400A on the distribution line 200A. In the example shown in FIG. 3B, the ground fault point is inside the first area R1 and is near the branch point on the distribution line 200A (closer to the measurement terminal 400A). It shall exist.

In FIGS. 3A and 3B, the measurement terminal 400A (first measurement terminal) is installed on the support column 600 at the first position of the distribution line 200A. The measuring terminal 400B (second measuring terminal) is installed on a support column 600 at a second position of the distribution line 200A separated from the measuring terminal 400A by a predetermined distance. The measuring terminal 400C is installed on a support column 600 at a third position of the distribution line 200B that branches from between the first position and the second position of the distribution line 200A.

In the example shown in FIGS. 3A and 3B, the distribution line 200 branches into a linear distribution line 200A (main line) and a dendritic shape (T-shape) from an arbitrary position on the distribution line 200A. It is formed including a distribution line 200B (branch line).

There are three combinations of the two measurement terminals 400 that sandwich the ground fault point (measurement terminals 400A and 400B, measurement terminals 400A and 400C, and measurement terminals 400B and 400C). Hereinafter, the three combinations of the two measuring terminals 400 that sandwich the ground fault point may be simply referred to as "three combinations". Further, the distance derived using the combination of the measuring terminals 400A and 400B is x ₁ , the distance derived using the combination of the measuring terminals 400A and 400C is x ₂ , and the distance derived using the combination of the measuring terminals 400B and 400C is derived. the distance and _{x 3.}

Here, in the example shown in FIGS. 3A and 3B, the ground fault point exists between the measuring terminal 400A and the measuring terminal 400B, and between the measuring terminal 400A and the measuring terminal 400C. However, it does not exist between the measuring terminal 400B and the measuring terminal 400C. When the ground fault point is defined by using the two measuring terminals 400B and 400C that do not sandwich the ground fault point, the ground fault point locating device 500 determines the position of the branch point. Therefore, the land絡点locating system 500, among the three distances _x 1 ~x ₃ derived by calculation based on equation (1) described above, two distances _x 1, _{x 2} is the actual earth絡点While the remaining one distance x ₃ is output as the localization result, the branch point is output as the orientation result.

Therefore, the ground fault point determining device 500 determines whether or not the ground fault point exists inside the first zone area R1, that is, the ground fault point is within a predetermined range from the branch point (for example, within a radius of 100 m from the branch point). ) Is present or not. Then, the ground fault point locating device 500 changes the ground fault point locating method depending on whether the ground fault point is inside the first area R1 or not. As a result, the ground fault point locating device 500 can improve the accuracy of the terrestrial point locating result in the terrestrial fault locating using the three measuring terminals 400 installed across the branch point.

A specific example will be described. First, as shown in FIG. 3A, the position of the ground fault point is outside the first area R1 and any one of the three measurement terminals 400 (FIG. 3 (FIG. 3). In the example shown in A), the case where the terminal exists in the vicinity of the measuring terminal 400A) will be described as an example.

In this case, when the calculation based on the equation (1) is performed using the value of the appropriate surge propagation velocity V, two of the three combinations (measurement terminals 400A and 400B and measurement terminals 400A and 400C) are obtained. The distances x ₁ and x ₂ derived using this indicate a position close to the actual ground fault point. In contrast, the distance x ₃ derived using the remaining one combination (the measurement terminal 400B and 400C) shows a position approximate to the branch point. As a result, as shown in FIG. 3C, the two distances x ₁ and x ₂ are outside the first category R1 and show positions close to each other. On the other hand, the remaining one distance x ₃ indicates the inside of the first category R1.

Thus, earth絡点locating system 500, one distance x _i of the three distances x _i derived is present inside the first sphere R1, and the other two distances x _i is the When it exists outside the one zone R1, it is determined that the arrangement pattern of the _{three distances x i corresponds to the "first pattern".} That is, the first pattern refers to an arrangement pattern in which the ground fault point does not exist near the branch point among the arrangement patterns of the ground fault points.

Next, a case where the ground fault point exists inside the first category R1 as shown in FIG. 3B will be described as an example.

Even in this case, if the calculation based on the equation (1) is performed using the value of the appropriate surge propagation velocity V, two of the three combinations (measurement terminals 400A and 400B and measurement terminals 400A and 400C) are used. The distances x ₁ and x ₂ derived using) indicate positions that are close to the actual ground fault point. However, when the ground fault point is inside the first category R1, the two distances x ₁ , x ₂ eventually indicate the vicinity of the branch point. As a result, _{all three distances x 1 to} x 3 indicate positions close to the branch point, and as shown in FIG. 3 (D), _{all three distances x 1 to} x 3 are first. The inside of the sphere R1 is shown.

In this way, in the ground fault point locating device 500, when _{all of the three derived distances x i} are located inside the first _{category area R1, the arrangement pattern of the three distances x i} is the "second pattern". It is determined that it corresponds to. That is, the second pattern refers to an arrangement pattern in which the ground fault points exist in the vicinity of the branch point among the arrangement patterns of the ground fault points.

<Output example of localization result>
Next, an output example of the localization result will be described. As shown in FIG. _3D , when the arrangement pattern of the three distances x i corresponds to the "second pattern", it is difficult to determine which of the _{three distances x i is defining the branch point.} May become. That is, it may be difficult to identify one of the three combinations that does not sandwich the ground fault point. Therefore, in the present embodiment, the ground fault point locating device 500 has a ground fault point inside the first area R1, that is, within a predetermined range from the branch point (for example, within a radius of 100 m from the branch point). The existence of the ground fault point is output as the localization result.

On the other hand, in the ground fault point locating device 500, when _{the arrangement pattern of the three distances x i} corresponds to the "first pattern", which of the three distances x _i branches as compared with the "second pattern". It is possible to easily determine whether or not a point is set. That is, it is possible to specify two of the three combinations that define the actual ground fault point. For example, in the example shown in FIG. 3A, in the ground fault point locating device 500, two distances x _i indicating the outside of the first area R1 indicate the actual ground fault point, and the first area R1 It can be easily grasped that _{one distance x i} indicating the inside of is indicating a branch point. Then, the ground fault point locating device 500 _{derives two distances x i} indicating the outside of the first area R1 (in the example shown in FIG. 3A, the measuring terminals 400A, 400B, and the measurement terminals 400A, 400B, and two combinations. It can be specified that the measurement terminals 400A and 400C) are a combination of the two that define the actual ground fault point.

<Location of ground fault points using four measuring terminals installed on distribution lines including branches>
4 (A) and 4 (B) are schematic views showing that four measuring terminals are installed on the distribution line including the cross branch. In the example shown in FIG. 4 (A), the ground fault point is outside the first area R1 and exists in the vicinity of the measurement terminal 400A on the distribution line 200A. The entanglement point exists inside the first area R1 and near the branch point on the distribution line 200A (closer to the measurement terminal 400A).

As shown in FIGS. 4A and 4B, the measurement terminal 400A (first measurement terminal) is installed on the support column 600 at the first position of the distribution line 200A. The measuring terminal 400B (second measuring terminal) is installed on a support column 600 at a second position of the distribution line 200A separated from the measuring terminal 400A by a predetermined distance. The measuring terminal 400C is attached to a support 600 at the third position of the distribution line 200B, which branches in one direction (downward in FIGS. 4A and 4B) from between the first position and the second position of the distribution line 200A. is set up. The measurement terminal 400D is attached to the support column 600 at the fourth position of the distribution line 200C, which branches from between the first position and the second position of the distribution line 200A in the other direction (upward in FIGS. 4A and 4B). is set up.

In the following, there are six combinations of the two measurement terminals 400 that sandwich the ground fault point (measurement terminals 400A, 400B, measurement terminals 400A, 400C, measurement terminals 400A, 400D, measurement terminals 400B, 400C, measurement terminals 400B, 400D and measurement terminals 400C, 400D). Hereinafter, the six combinations of the two measuring terminals 400 that sandwich the ground fault point may be simply referred to as "six combinations".

In the example shown in FIGS. 4A and 4B, the ground fault points are between the measuring terminal 400A and the measuring terminal 400B, between the measuring terminal 400A and the measuring terminal 400C, and between the measuring terminal 400A and the measuring terminal 400D. Exists between. On the other hand, there is no ground fault between the measuring terminal 400B and the measuring terminal 400C, between the measuring terminal 400B and the measuring terminal 400D, and between the measuring terminal 400C and the measuring terminal 400D.

In this case, when the calculation based on the equation (1) is performed using three combinations (measurement terminals 400A, 400B, measurement terminals 400A, 400C, and measurement terminals 400A, 400D) sandwiching the ground fault point, the ground fault point is determined. Device 500 locates the actual ground fault point. On the other hand, when the calculation based on the equation (1) is performed using three combinations (measurement terminals 400B, 400C, measurement terminals 400B, 400D, and measurement terminals 400C, 400D) that do not sandwich the ground fault point, the ground fault The point locating device 500 positions the position of the branch point.

Therefore, the ground fault point locating device 500 also uses the three measuring terminals 400 to determine the ground fault point using the four measuring terminals 400 installed on the distribution line 200 including the branch. As in the case of performing localization, it is determined whether or not it exists inside the first zone R1. Then, the ground fault point locating device 500 changes the ground fault point locating method depending on whether the ground fault point is inside the first area R1 or not. As a result, the ground fault point locating device 500 can improve the accuracy of the terrestrial point locating result even in the terrestrial fault locating using the four measuring terminals 400 installed across the branch point.

A specific example will be described. First, as shown in FIG. 4 (A), the position of the ground fault point is outside the first area R1 and any one of the four measurement terminals 400 (FIG. 4 (FIG. 4). In the example shown in A), the case where the terminal exists in the vicinity of the measuring terminal 400A) will be described as an example.

Here, the distance derived using the combination of _{the measuring terminals 400A and 400B is x 1} , the distance derived using the combination of the measuring terminals 400A and 400C is x ₂ , and the combination of the measuring terminals 400A and 400D is used. the derived distance _{x 3,} the measurement terminal 400B, the distance derived using a combination of 400C _{x 4,} measurement terminal 400B, the distance derived using a combination of 400D _{x 5,} measurement terminal 400C, the 400D _{Let x 6} be the distance derived using the combination.

When the calculation based on the equation (1) is performed using the value of the appropriate surge propagation velocity V, three of the six combinations (measurement terminals 400A, 400B, measurement terminals 400A, 400C, and measurement terminal 400A, _{Distances x 1 to x 3} derived using 400D) indicate positions close to the actual ground fault point. _{On the other hand, the distances x 4 to x 6} derived using the remaining three combinations (measurement terminals 400B and 400C, measurement terminals 400B and 400D, and measurement terminals 400C and 400D) are positions close to the branch point. Shown. As a result, as shown in FIG. 4 (C), 3 one distance x ₁ ~x _3, rather than the first sphere R1 an outer, showing the positions close to each other. On the other hand, the remaining three distances x _{4 to x 6} indicate the inside of the first category R1.

Thus, earth絡点locating system 500, three distances x _i of the derived six distance x _i exists outside the first sphere R1, and, the other three distances x _i When it exists inside the first sphere R1 and exists at a position close to each other, it is determined that the arrangement pattern of the _{six distances x i corresponds to the "first pattern".}

Next, a case where the ground fault point exists inside the first category R1 as shown in FIG. 4B will be described as an example. Even in this case, when the calculation based on the equation (1) is performed using the value of the appropriate surge propagation velocity V, three combinations (measurement terminals 400A, 400B, measurement terminals 400A, 400C, and) out of the six combinations are performed. , Measurement terminals 400A, 400D), and the distances x _{1 to x 3} derived using the measurement terminals (400A, 400D) indicate positions close to the actual ground fault point. However, when the ground fault point is inside the first category R1, the three distances x _{1 to x 3} eventually indicate the vicinity of the branch point. As a result, _{all of the six distances x 1 to} x 6 indicate positions close to the branch point, and as shown in FIG. 4 (D), _{all of the six distances x 1 to} x 6 are the first. It shows the inside of one area R1.

As described above, in the ground fault point locating device 500, when all of the derived six distances x _i are located within a predetermined range from the branch point _{, the arrangement pattern of the six distances x i} is the "second pattern". It is determined that it corresponds to. The method of outputting the localization result after pattern discrimination is the same as the case of using three measurement terminals installed on the distribution line including the branch.

<Outline configuration of ground fault point locator>
FIG. 5 is a block diagram showing the functions of the ground fault point locating device used in the ground fault point locating system according to the present embodiment. The ground fault point locating device 500 is configured to include a microcomputer, and the functions of the ground fault point locating device 500 are realized by the microcomputer executing software processing according to a program.

As shown in FIG. 5, the ground fault point locating device 500 mainly includes a pattern discriminating unit 510 and a locating unit 520. The pattern discriminating unit 510 is inside the first zone R1 centered on the branch point when the ground fault point is determined by using three or more measuring terminals 400 installed on the distribution line 200 across the branch. It is determined whether or not there is a ground fault point in. The positioning unit 520 positions the ground fault point based on the determination result of the pattern determination unit 510. Specifically, the positioning unit 520 changes the ground fault point positioning method according to the determination result of the pattern determination unit 510. Hereinafter, the configurations of the pattern determination unit 510 and the standardization unit 520 will be specifically described.

<Structure of pattern discrimination unit>
First, the configuration of the pattern discriminating unit 510 will be described with reference to FIG. FIG. 6 is a block diagram of the pattern discriminating unit 510. As shown in FIG. 6, the pattern determination unit 510 mainly includes a first calculation unit 511 and a first diagnosis unit 512.

The first calculation unit 511 performs a calculation based on the equation (1) and derives the _{distance x i.} Specifically, the first calculation unit 511 performs a calculation based on the equation (1) using the information obtained from the plurality of measurement terminals 400. For example, when the ground fault point is set using three measurement terminals 400 installed across a branch, the first calculation unit 511 performs a calculation for each of the three combinations and calculates _{three distances x i.} To do.

The first diagnostic unit 512, based on the calculation result of the first calculation unit 511, to diagnose the arrangement pattern of the plurality of distance x _i. For example, when the ground fault point is determined by using the three measuring terminals 400 installed across the branch, the first diagnostic unit 512 has _{the arrangement pattern of the three distances x i} as the "first pattern" or "the first pattern". Diagnosis is made as to whether or not any of the "second patterns" is applicable.

The pattern determination unit 510 further includes an initial value storage unit 513, a speed generation unit 514, and a speed setting unit 515. The initial value storage unit 513 stores the initial value defV, which is a speed value to be substituted for the surge propagation speed V when the first calculation unit 511 first performs the calculation based on the equation (1). The initial value defV stored in the initial value storage unit 513 can be arbitrarily set by the user of the ground fault point determination system 100.

When the speed generation unit 514 substitutes a speed value different from the initial value defV into the surge propagation speed V and performs the calculation based on the equation (1) again, the speed generation unit 514 generates a speed value to be substituted into the surge propagation speed V.

The speed setting unit 515 sets a speed value to be substituted for the surge propagation speed V when performing the calculation based on the equation (1). Specifically, the speed setting value 515 uses the initial value defV stored in the initial value storage unit 513 as a surge in the equation (1) when the first calculation unit 511 first performs an operation based on the equation (1). Set to the speed value to be substituted for the propagation speed V. On the other hand, when the speed setting unit 515 performs the calculation based on the equation (1) using the initial value defV and then performs the calculation based on the equation (1) again, the speed setting unit 514 determines the speed value generated by the speed generation unit 514. Set to the speed value to be substituted for the surge propagation speed V in the equation (1).

After that, for example, when the ground fault point locating device 500 positions the ground fault point using three measuring terminals 400 installed across the branch, the first calculation unit 511 sets the speed set by the speed setting unit 515. Substituting the value into the surge propagation velocity V, the calculation based on the equation (1) is performed, and three distances x _i are derived. After that, the first diagnosis unit 512 diagnoses _{whether or not the arrangement pattern of the three distances x i} corresponds to either the first pattern or the second pattern.

As a result, when the first diagnosis unit 512 _{can discriminate the arrangement pattern of the three distances x i} into either the first pattern or the second pattern, the standardization unit 520 determines the arrangement pattern by the pattern determination unit 510. The ground fault point is defined by the method according to, and the positioning result is output.

Here, the speed setting unit 515 assigns the value of the surge propagation speed V to be substituted into the equation (1) when the first arithmetic unit 511 performs an operation based on the equation (1) in determining the arrangement pattern of the ground fault points. As, the initial value defV stored in the initial value storage unit 513 is used. In this regard, the initial value defV is set with reference to the surge propagation speed at the time of a ground fault that occurred in the past on the corresponding distribution line 200. That is, the value stored in the initial value storage unit 513 as the initial value is a predicted value based on the past actual results, and is a speed value that is highly likely to be equivalent to the actual surge propagation speed. Therefore, when the pattern discriminating unit 510 first performs the calculation based on the equation (1), the initial value defV set as described above is substituted for the surge propagation velocity V, so that the ground fault point in the first calculation is performed. It is possible to increase the possibility of discriminating the arrangement pattern of.

In addition to this, the user of the ground fault point determination system 100 was able to determine the corresponding arrangement pattern as a result of performing the calculation based on the equation (1) using the highly credible velocity value as the surge propagation velocity V. In this case, the localization result output by the localization unit 520 after that can be easily trusted.

That is, if the value of the surge propagation velocity V used when the arrangement pattern of the ground fault point could be determined, the value of the surge propagation velocity V greatly deviated from the range of the surge propagation velocity V predicted based on the user's experience and achievements. In some cases, the user may find it difficult to accept the localization result output by the localization unit 520. That is, the user is worried that there may have been some mistake in the process of deriving the reference value using the ground fault point positioning device 500. As a result, the user wants to perform additional confirmation work such as re-deriving using the ground fault point locating device 500, or performing localization by another method and verifying the locating result of the ground fault point locating device 500. There is a risk of thinking.

On the other hand, the pattern discrimination unit 510 stores a highly credible speed value as the surge propagation speed V in the initial value storage unit 513, derives the distance using the initial value, and performs pattern discrimination. Therefore, the user can smoothly accept the positioning result output by the positioning unit 520, and can immediately shift to the response to the ground fault.

On the other hand, when the initial value defV is not an appropriate surge propagation velocity V (the initial value defV is different from the actual surge propagation velocity V), the first diagnostic unit 512 has a plurality of distance x _i arrangement patterns as the first pattern and It is not possible to determine which of the second patterns is applicable.

Therefore, in this case, the speed setting unit 515 substitutes the speed value generated by the speed value generation unit 514 into the surge propagation speed V in the equation (1), and the first calculation unit 511 newly substitutes into the surge propagation speed V. The calculation based on the equation (1) is performed using the speed value. Then, the first diagnostic unit 512 attempts to discriminate the arrangement pattern of _{a plurality of distances x i} derived by the calculation based on the equation (1) using the new surge propagation velocity V. At this time, the pattern determination unit 510 performs an operation by the first calculation unit 511 using the plurality of speed values generated by the speed value generation unit 514, and the first diagnosis unit 512 determines _{the derived distances x i.} Make a diagnosis.

The pattern determination unit 510 further includes a speed condition storage unit 516, a speed condition determination unit 517, a diagnosis result storage unit 518, and a second diagnosis unit 519. The velocity condition storage unit 516 stores the range of the surge propagation velocity V that can be defined as the condition of the surge propagation velocity V. In the present embodiment, the condition of the surge propagation speed V is 50 m / μs ≦ v ≦ 300 m / μs. The velocity condition determination unit 517 determines whether or not the velocity value generated by the velocity value generation unit 514 meets the condition (velocity condition) of the surge propagation velocity V stored in the velocity condition storage unit 516. Then, when the speed value assigned to the surge propagation speed V meets the condition of the surge propagation speed V, the first calculation unit 511 performs a calculation based on the equation (1) to derive the _{distance x i.}

The diagnosis result storage unit 518 stores the diagnosis result by the first diagnosis unit 512 in association with the surge propagation speed V. Specifically, the diagnosis result storage unit 518 uses the diagnosis result of the arrangement pattern of the _{plurality of distances x i} by the first diagnosis unit 512 when the first calculation unit 511 derives the _{plurality of distances x i.} It is stored in association with the value of the propagation velocity V.

The second diagnosis unit 519 diagnoses the arrangement pattern of the ground fault point based on the diagnosis result stored in the diagnosis result storage unit 518. Specifically, the first calculation unit 511 performs a calculation by the first calculation unit 511 using a plurality of speed values stored in the speed range stored in the speed condition storage unit 516, and each time the first calculation unit 511 performs a calculation. 512 diagnoses a plurality of derived distance x _i placement patterns. The diagnosis result of the first diagnosis unit 512 is stored in the diagnosis result storage unit 518, and when the second diagnosis unit 519 can determine an arrangement pattern of _{a plurality of distances x i from the stored diagnosis results.} The surge propagation velocity V used in the calculation based on the performed equation (1) is extracted. Hereinafter, the diagnostic method by the second diagnostic unit 512 will be described with reference to specific examples.

FIG. 7 shows an example of the diagnosis result of the arrangement pattern of the _{three distances x i} stored in the diagnosis result storage unit 518 when the ground fault point is defined by using the three measurement terminals 400 installed across the branch. It is a figure which shows.

In the example shown in FIG. 7, the first calculation unit 511 is based on the equation (1) while sequentially changing the speed value assigned to the surge propagation speed V by a constant value (for example, 1 m / μs) in the speed value generation unit 514. Each time the calculation is performed, the first diagnostic unit 512 diagnoses the arrangement pattern of _{the three derived distances x i.} Then, the pattern determination unit 510 stores the diagnosis result of the first diagnosis unit 512 in the diagnosis result storage unit 518 in association with the surge propagation speed V.

When the calculation by the first calculation unit 511 and the diagnosis by the first diagnosis unit 512 are completed, the second diagnosis unit 519 arranges _{three distances x i from the diagnosis results stored in the diagnosis result storage unit 518.} The surge propagation velocity V used in the calculation based on the equation (1) when the pattern can be discriminated is extracted.

As a result, _{if there is only one surge propagation velocity V capable of discriminating the arrangement pattern of the three distances x i} , the second diagnosis unit 519 determines the arrangement pattern as the diagnosis result by the second diagnosis unit 519. On the other hand, _{when there are a plurality of surge propagation velocities V capable of discriminating the arrangement patterns of the three distances x i} , the second diagnostic unit 519 has the largest difference from the initial value defV stored in the initial value storage unit 513. The arrangement pattern associated with the small surge propagation velocity V is determined as the diagnosis result (arrangement pattern of the ground fault point) by the second diagnosis unit 519.

For example, in the example shown in FIG. 7A, in the first diagnostic unit 512, _{the arrangement pattern of the three distances x i} obtained by substituting (defV-5) m / μs for the surge propagation velocity V is "the first". It was diagnosed that it corresponds to "1 pattern". Further, in the example shown in FIG. 7A, in the first diagnosis unit 512, _{the arrangement pattern of the three distances x i} obtained by substituting (defV + 5) m / μs for the surge propagation velocity V is the “second pattern”. Was diagnosed. That is, in this case, in the diagnosis result stored in the diagnosis result storage unit 518, there are two surge propagation velocities V capable of discriminating the arrangement patterns of the _{three distances x i.}

Regarding this example, the two surge propagation velocities (defV-5) and (defV + 5) have the same difference from the initial value defV. In this case, the second diagnosis unit 519 can select either the "first pattern" or the "second pattern". As will be described later, when the diagnosis is "first pattern", the position of the ground fault point output as the positioning result by the positioning unit 520 is higher than that when the diagnosis is "second pattern". More limited. In this respect, in the example shown in FIG. 7A, it is desirable to select the "first pattern" as the diagnosis result by the second diagnosis unit 519.

Further, in the example shown in FIG. 7B, in the first diagnostic unit 512, _{the arrangement pattern of the three distances x i} obtained by substituting (defV-5) m / μs for the surge propagation velocity V is "the first". It was diagnosed that it corresponds to "1 pattern". Further, in the example shown in FIG. 7B, in the first diagnosis unit 512, _{the arrangement pattern of the three distances x i} obtained by substituting (defV + 4) m / μs for the surge propagation velocity V is the “second pattern”. Was diagnosed. That is, in the diagnosis result stored in the diagnosis result storage unit 518, there are two surge propagation velocities V capable of discriminating the arrangement patterns of the _{three distances x i.}

In this case, the surge propagation velocity (defV + 4) on one side has a smaller difference from the initial value defV than the surge propagation velocity (defV-5) on the other side. Therefore, the second diagnostic unit 519 selects the "second pattern" associated with one surge propagation velocity (defV + 4).

As described above, the second diagnosis unit 159 initially finds the diagnosis result stored in the diagnosis result storage unit 518 when there are a plurality of surge propagation velocities V capable of discriminating the arrangement patterns of the _{three distances x i.} The arrangement pattern associated with the surge propagation velocity V having a small difference from the value defV is determined as the diagnosis result (arrangement pattern of the ground fault point) by the second diagnosis unit 519. That is, the second diagnostic unit 519 diagnoses the arrangement pattern of the _{three distances x i} derived by the first arithmetic unit 511 when a velocity value close to the highly reliable initial value defV is used as the surge propagation velocity V. Take precedence over other diagnostic results.

As a result, the surge propagation velocity V used by the pattern discrimination unit 510 to discriminate _{the arrangement pattern of the three distances x i} is likely to be a velocity value close to the initial value defV. Therefore, the user of the ground fault point determination system 100 arranges the surge propagation velocity V as a result of performing the calculation based on the equation (1) using the velocity value approximated to the initial value which is a highly credible predicted value. When the pattern can be determined, the localization result output by the estimation unit 520 after that can be easily trusted. Therefore, the user can smoothly accept the positioning result output by the positioning unit 520, and can immediately shift to the response to the ground fault accident (for example, patrol work).

<Structure of the control section>
Next, the configuration of the control unit 520 will be described with reference to FIG. FIG. 8 is a block diagram of the positioning unit 520. As shown in FIG. 8, the standardization unit 520 includes a first calculation unit 521, a second calculation unit 522, a speed condition storage unit 523, a speed condition determination unit 524, a third calculation unit 525, and a standardization result output. A unit 526 is provided.

The first calculation unit 521 has the same configuration as the first calculation unit 511 provided in the pattern determination unit 510, and performs an calculation based on the equation (1). _{When the arrangement pattern of the three distances x i} is the "first pattern", the second calculation unit 522 performs the calculation based on the above equation (3), and then the first calculation unit 521 performs the calculation (1). ) Is derived from the surge propagation velocity V to be substituted when performing the calculation.

For example, when the ground fault point is determined by using three measurement terminals 400 installed across the branch, the second calculation unit 522 if _{the arrangement pattern of the three distances x i} is the "first pattern". from among the three distances x _i, extracts the actual two distances indicating the position that approximates the land絡点of x _{i (two} distances x _i present outside the first sphere _R1). Then, the second calculation unit 522 uses _{two combinations when deriving the two extracted distances x i} (in the example shown in FIG. 3A, the combination of the measurement terminals 400A and 400B, and the measurement terminal. The operation based on the equation (3) is performed using (combination of 400A and 400C) to derive the surge propagation velocity V.

In this way, if _{the arrangement pattern of the three distances x i} is the "first pattern", the locating unit 520 can specify the _{two distances x i indicating a position close to the actual ground fault point.} Then, the positioning unit 520 can specify two combinations of the two measuring terminals 400 arranged so as to sandwich the ground fault point. As a result, the localization unit 520 can derive the surge propagation velocity V by performing the calculation based on the equation (3) using the combination of the two. Therefore, the ground fault point locating device 500 can accurately obtain the surge propagation velocity V when the arrangement pattern _{of the ground fault point distance x i is the "first pattern".}

The speed condition storage unit 523 has the same configuration as the speed condition storage unit 516 provided in the pattern determination unit 510, and stores the condition of the surge propagation speed V derived by the calculation by the second calculation unit 522. .. In the present embodiment, the condition of the surge propagation speed V is 50 m / μs ≦ v ≦ 300 m / μs. The speed condition stored in the speed condition storage unit 523 of the standardization unit 520 may be the same as or different from the speed condition stored in the speed condition storage unit 516 of the pattern determination unit 510.

The speed condition determination unit 524 has the same configuration as the speed condition calculation unit 517 provided in the pattern determination unit 510, and the value of the surge propagation speed V derived by the calculation by the second calculation unit 522 is the speed. It is determined whether or not the condition of the surge propagation speed V stored in the condition storage unit 523 is satisfied.

Then, when the speed condition determination unit 524 determines that the surge propagation speed V conforms to the speed condition stored in the speed condition storage unit 523, the standardization unit 520 continues to use the derived surge propagation speed V. Calculation is performed by the third calculation unit 525. On the other hand, when the velocity condition determination unit 524 determines that the surge propagation velocity V does not meet the velocity condition, the reference unit 520 determines that the reference value x (_) cannot be derived.

The orientation result output unit 526 outputs the orientation result by the orientation unit 520 in a manner that can be grasped by the user of the ground fault point assignment system 100. The localization result output unit 526 outputs the calculation result by the third calculation unit 525 when the pattern determination unit 510 determines that the arrangement pattern of the ground fault points is the “first pattern”. Further, when the pattern determination unit 510 determines that the arrangement pattern of the ground fault point is the "second pattern", the localization result output unit 526 "is within a predetermined range from the branch point (for example, within a radius of 100 m from the branch point). ) ”To output that there is a ground fault point. On the other hand, when the arrangement pattern of the ground fault points does not correspond to any of the "first pattern" and the "second pattern", the ground fault point output unit 526 says "the ground fault point cannot be fixed". Output to that effect. When the localization result output unit 526 determines that the arrangement pattern of the ground fault points corresponds to the "first pattern" or the "second pattern", the localization result output unit 526 also outputs the surge propagation velocity V used for the determination. May be good.

<Ground fault point determination process>
Next, with reference to FIG. 9, the ground fault point locating step executed by the ground fault point locating device 100 will be described. FIG. 9 is a flowchart showing the ground fault point determination process. Here, in the example shown in FIG. 3, a case where the ground fault point is defined by using three measuring terminals 400 installed on the distribution line 200 including the T-shaped branch will be described as an example.

As shown in FIG. 9, the ground fault point locating device 500 executes the pattern determination step (S100) as the first process performed in the ground fault point locating step. This pattern determination step (S100) is a process executed by the pattern determination unit 510, and determines the arrangement pattern of the ground fault points. The pattern determination step (S100) will be described in detail with reference to FIGS. 10 to 13.

The ground fault point locating device 500 executes the locating step (S200) after the pattern determination step (S100) is completed. The standardization step (S200) is a process executed by the standardization unit 520, and based on the determination result by the pattern determination step (S100), the ground fault point is standardized and the standardization result is output. The standardization step (S200) will be described in detail with reference to FIG.

<Pattern discrimination process>
Next, the pattern determination step (S100) will be described with reference to FIG. FIG. 10 is a flowchart showing a pattern determination step (S100) executed in the ground fault point determination step. As shown in FIG. 10, the pattern discriminating unit 510 executes the first discriminating step (S110) as the first process executed in the pattern discriminating step (S100). The first determination step (S110) is a step of determining the arrangement pattern of the ground fault point by using the initial value defV stored in the initial value storage unit 513 for the surge propagation velocity V. The first determination step (S110) will be described in detail with reference to FIG.

After the processing of S110 is completed, the pattern determination unit 510 determines in the first determination step (S110) whether or not the arrangement pattern of the ground fault points can be determined (S120). Specifically, in the process of S120, _{it is determined whether or not the arrangement pattern of the three distances x i} corresponds to any of the "first pattern" and the "second pattern".

As a result, when the arrangement pattern of the ground fault points cannot be discriminated (S120: No), the pattern discriminating unit 510 executes the second discriminating step (S130). The second determination step (S130) is a step of determining the arrangement pattern of the _{three distances x i} while substituting a velocity value other than the initial value defV into the surge propagation velocity V. The second determination step (S130) will be described in detail with reference to FIGS. 12 and 13.

<First discrimination process>
Next, the first determination step (S110) executed in the pattern determination unit 510 will be described with reference to FIG. FIG. 11 is a flowchart showing the first determination step (S110).

As shown in FIG. 11, as the first process executed in the first determination step (S110), the speed setting unit 515 is stored in the initial value storage unit 513 in the value of the surge propagation speed V in the equation (1). The initial value defV is substituted (S111). Next, the first calculation unit 511 describes the equation (1) for each of the three combinations (measurement terminal 400A and measurement terminal 400B, measurement terminal 400A and measurement terminal 400C, measurement terminal 400B and measurement terminal 400C) that sandwich the branch point. Is performed, and three distances x _i (x _{1 to x 3} ) are derived (S112). After that, the first diagnosis unit 512 diagnoses the arrangement pattern of the three distances x _{i based on the arrangement pattern of the three distances x i} derived by the first calculation unit 511 (S113), and the pattern determination unit 510 determines the pattern. This process ends.

<Second discrimination process>
Next, the second determination step (S130) executed in the pattern determination unit 510 will be described with reference to FIG. FIG. 12 is a flowchart showing the second determination step (S130).

As shown in FIG. 12, as the first process executed in the second determination step (S130), the speed value generation unit 514 generates the minimum value minV of the speed condition stored in the speed condition storage unit 517 as a speed value. To do. Then, the speed setting unit 515 sets the minimum value minV (50 m / μs in this embodiment) to the value of the surge propagation speed V in the equation (1) (S131).

Next, the first calculation unit 511 performs a calculation based on the equation (1 _{) and derives three distances x i} (x _{1 to} x 3) (S132). Specifically, the velocity setting unit 515 substitutes the velocity value generated by the velocity value generation unit 514 into the surge propagation velocity V in the equation (1). Subsequently, the first calculation unit 511 describes the equation (1) for each of the three combinations (measurement terminal 400A and measurement terminal 400B, measurement terminal 400A and measurement terminal 400C, measurement terminal 400B and measurement terminal 400C) that sandwich the branch point. Performs operations based on. Next, the first diagnosis unit 512 diagnoses _{the arrangement pattern of the three distances x i} derived by the first calculation unit 511 (S133), and stores the diagnosis result in the diagnosis result storage unit 518 (S134). That is, the first diagnostic unit 512 _{determines whether or not the arrangement pattern of the three distances x i} corresponds to either the first pattern or the second pattern, and if any of the arrangement patterns is applicable, the arrangement is made. The pattern is stored in the diagnosis result storage unit 518.

After the processing of S134, the velocity value generation unit 514 newly generates a velocity value obtained by adding 1 to the value of the surge propagation velocity V set in the velocity setting unit 515 (S135). Next, the velocity condition determination unit 517 determines whether or not the value of the surge propagation velocity V is larger than the maximum value maxV of the velocity condition stored in the velocity condition storage unit 518 (S136). As a result, if the value of the surge propagation velocity V is equal to or less than the maximum value maxV (S136: No), the pattern determination unit 510 returns to the process of S132. That is, the speed setting unit 515 substitutes the speed value generated by the speed value generation unit 514 into the surge propagation speed V in the equation (1), and the first calculation unit 511 performs an operation based on the equation (1). On the other hand, when the value of the surge propagation velocity V exceeds the maximum value maxV (S136: Yes), the pattern determination unit 510 executes the pattern determination process shown in FIG. 13 (S137).

<Pattern determination process>
Next, the pattern determination process (S137) executed in the second determination step (S130) will be described with reference to FIG. FIG. 13 is a flowchart showing the pattern determination process (S137). The pattern determination process (S137) is a process of determining the arrangement pattern of the ground fault points based on the diagnosis result stored in the diagnosis result storage unit 518.

As shown in FIG. 13, as the first process executed in the pattern determination process (S137), the second diagnosis unit 519 has three distances x in the diagnosis result stored in the diagnosis result storage unit 518. _It is determined whether or not there are a plurality of surge propagation velocities V for which the arrangement pattern of i can be determined (S138).

As a result, _{when there are a plurality of surge propagation speeds V for which the arrangement patterns of the three distances x i} can be discriminated (S138: Yes), the second diagnostic unit 519 sets the value of the surge propagation speed V to the initial value def. The arrangement pattern associated with the closest one is determined as the arrangement pattern of the ground fault point (S139).

On the other hand, _{when there are no plurality of surge propagation velocities V for which the arrangement patterns of the three distances x i} can be discriminated (S138: No), the second diagnosis unit 519 is subsequently stored in the diagnosis result storage unit 518. It is determined whether or not there is only one surge propagation velocity V for which the arrangement pattern of the _{three distances x i} can be discriminated in the diagnosis result (S140).

As a result, when there is only one surge propagation velocity V whose ground fault arrangement pattern can be discriminated (S140: Yes), the second diagnostic unit 519 is associated with the value of the surge propagation velocity V. The arrangement pattern is determined as the arrangement pattern of the ground fault point (S141). On the other hand, when there is no surge propagation velocity V for which the arrangement pattern of the ground fault point can be determined (S140: No), the second diagnostic unit 519 cannot determine the arrangement pattern of the ground fault point. It is determined that there is, and this process is terminated as it is.

In the present embodiment, the speed setting unit 515 sets the minimum value minV for the surge propagation speed V in the processing of S131, and the speed value generation unit 514 sets the surge propagation speed set in the speed setting unit 515 in the processing of S135. The case where 1 is added to the value of the velocity V has been described as an example. However, it is not limited to this.

For example, the speed setting unit 515 sets the maximum value maxV for the surge propagation speed V in the processing of S131, and the speed value generation unit 514 uses the value of the surge propagation speed V set in the speed setting unit 515 in the processing of S135. 1 may be subtracted. In this case, the pattern determination unit 510 determines whether or not the value of the surge propagation velocity V is less than the minimum value min in the process of S136. Then, the pattern determination unit 510 shifts to the processing of S137 when the value of the surge propagation speed V is less than the minimum value min, and proceeds to the processing of S132 when the value of the surge propagation speed V is equal to or more than the minimum value min. Return.

Further, the speed setting unit 515 sets a value close to the initial value defV (for example, the initial value defV ± 1) to the surge propagation speed V in the processing of S131, and the speed value generation unit 514 sets the speed in the processing of S135. It is also possible to set the value of the surge propagation speed V set in the setting unit 515 to a value such that the difference between the initial values defV gradually increases. _{In this case, as soon as the pattern determination unit 510 can determine the arrangement pattern of the three distances x i by} the process of S133, the pattern determination unit 510 may determine the arrangement pattern as the arrangement pattern of the ground fault point. That is, in this case, the value of the surge propagation velocity V used when the arrangement pattern can be determined is inevitably the velocity value closest to the initial value defV. Therefore, in this case, the process of S137 can be omitted in the second determination step (S130).

<Positioning process>
Next, the locating step (S200) executed by the locating unit 520 will be described with reference to FIG. FIG. 14 is a flowchart showing the locating process (S200).

As shown in FIG. 14, as the first process performed in the locating step (S2), the locating unit 520 sets the ground fault point arrangement pattern (three distances x _{i) based on the discrimination result in the pattern discriminating step (S100).} (S201), it is determined whether or not the arrangement pattern) corresponds to the “first pattern”.

As a result, when the arrangement pattern of the ground fault points corresponds to the "first pattern" (S201: Yes), the second calculation unit 522 uses a combination of two measuring terminals 400 arranged across the ground fault points. The pattern propagation velocity V is derived by performing an operation based on the equation (3) (S202). Next, the speed condition determination unit 524 determines whether or not the surge propagation speed V derived in the process of S202 meets the speed condition (minV ≦ V ≦ maxV) stored in the speed condition storage unit 523. (S203).

On the other hand, in the process of S201, when it is determined that the ground fault point arrangement pattern does not correspond to the "first pattern" (S201: Yes), the locating unit 520 subsequently changes the ground fault point arrangement pattern to the "first pattern". It is determined whether or not it corresponds to "2 patterns" (S207).

As a result, when the arrangement pattern of the ground fault points corresponds to the "second pattern" (S207: Yes), the localization result output unit 526 determines that "the ground fault points exist within the range of XX from the branch point". The result is output (S208), and this process is terminated.

On the other hand, in the processing of S203, when the surge propagation velocity V derived by the calculation based on the equation (3) does not meet the velocity condition (S203: No), or the ground fault point arrangement pattern is the "first pattern" and When none of the "second patterns" is applicable (S207: No), the localization result output unit 526 indicates that "the arrangement pattern of the ground fault points cannot be determined and the ground fault points cannot be determined". The localization result is output (S209), and this process is terminated.

In this way, the ground fault point locating device 500 determines whether or not the ground fault point exists inside the first area R1. Then, the ground fault point locating device 500 changes the ground fault point locating method depending on whether the ground fault point exists inside the first area R1 or not. As a result, the ground fault point locating device 500 can perform the ground fault point locating more accurately.

In addition, in FIGS. 9 to 14, the case where the ground fault point is defined by using three measuring terminals installed on the distribution line including the T-shaped branch has been described as an example, but the distribution line including the cross branch has been described. The same applies to the case where the ground fault point is determined using the four measuring terminals installed in.

<Modification example in the locating process>
Here, a modified example of the locating step (S200) will be described with reference to FIGS. 15 and 16. In the above-mentioned localization step (S200), when it is determined in the process of S207 that the second pattern is applicable, the orientation result output unit 526 determines that "a ground fault point exists within the range of XX from the branch point". The case where the result is output (S208) has been described. On the other hand, in the modification shown below, the range in which the ground fault point exists is further limited based _{on the three distances x i} derived by using the surge propagation velocity V when the arrangement pattern can be determined. The same components as those described above are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 15, the standardization unit 530 in the modified example further includes a fourth calculation unit 537 in addition to the configuration of the standardization unit 520 described in the above embodiment. The fourth calculation unit 537 performs a calculation for limiting the range in which the ground fault point exists when the arrangement pattern of the plurality of distances x _{i is the “second pattern”.} Then, the positioning unit 530 presents the calculation result by the fourth calculation unit 537 as the positioning result in a manner that can be grasped by the user.

FIG. 16 shows when it is determined that the arrangement pattern of the _{three distances x i} corresponds to the “second pattern” when the ground fault point is determined by using the three measurement terminals 400 installed across the branch. , It is a schematic diagram for demonstrating the process of deriving the second area R2 which shows the range where a ground fault point exists.

Fourth arithmetic unit 537, among the three distances _{x i (x 1 ~x 3)} , ( in the example shown in FIG. 16 _{x 1)} the distance _{x i} present in a position farthest from the branch point to extract. Subsequently, the fourth calculation unit 537 is a circle centered on the branch point, and has a radius of the distance r2 between the distance _{xi and the branch point located at the position farthest from the branch point.} To form. As a result, the three distances x _i are included on the line of the second category R2 or inside the second category R2, and the localization unit 530 is in the second category R2 formed by the fourth calculation unit 537. It is determined that there is a ground fault point on the included distribution lines 200A and 200B. The localization result output unit 526 outputs a localization result indicating that "a ground fault point exists within a" radius r2 "from the branch point" based on the localization result by the fourth calculation unit 537.

As described above, in the present modification, the positioning unit 530 can further limit the range in which the ground fault points exist when the arrangement pattern of the ground fault points is the “second pattern”. Therefore, the user of the ground fault point determination system 100 can shorten the time required to identify the ground fault point.

In addition, regarding this modification, _{there are cases where three distances x i} are lined up in a straight line. In this case, the locating unit 530 can also output a scoring result indicating that "a ground fault point exists on a line segment connecting two distances located at both ends of the three distances arranged in a straight line". is there. Further, in this case, the positioning unit 530 _{can output the three distances x i} as they are as positions where the ground fault point is likely to exist. That is, since two distances x _i out of the three distances x _i indicate a position close to the ground fault point, the user of the ground fault point locating system 100 can output the three distances x _i. By grasping, the position where the ground fault point exists can be narrowed down.
=== Summary ===

As described above, the ground fault point positioning system 100 according to the present embodiment can communicate with a plurality of measurement terminals 400 installed across the branch point on the distribution line 200 including the branch and with the plurality of measurement terminals 400. It is configured to include a ground fault point locating device 500 connected to the above. When a ground fault occurs in the distribution line 200, the plurality of measurement terminals 400 currently provide information indicating the zero-phase current and the zero-phase voltage output from the sensors 310 and 320 that detect the current and voltage of the distribution line 200. The information associated with the information indicating the time is transmitted to the ground fault point locating device 500. Further, the ground fault point locating device 500 uses the information transmitted from the combination of any two measurement terminals 400 among the three or more measurement terminals 400 installed across the branch point and the surge propagation speed. Based on this, the ground fault point of the distribution line 200 is defined. The ground fault point locating device 500 includes a determination unit 510 that determines whether or not the ground fault point exists inside a predetermined sphere centered on the branch point of the distribution line 200. Further, the ground fault point locating device 500 further includes a terrestrial fault locating unit 520 for locating the ground fault point based on the information, the surge propagation velocity, and the discrimination result of the discrimination unit 510. The positioning unit 520 changes the method of locating the ground fault point according to the determination result of the determination unit 510. With the configuration of the present embodiment as described above, it is possible to accurately determine the ground fault point when a ground fault occurs in the distribution system consisting of the distribution line 200 including the branch points such as the T-shaped branch and the cross branch. It becomes.

Further, the determination unit 510 transmits the information transmitted from a plurality of combinations including any two measurement terminals 400 out of three or more measurement terminals 400 in order for the determination unit 520 to accurately determine the ground fault point. Based on the above and the surge propagation speed, the first calculation unit 511 that derives the distance from the predetermined measurement terminal 400 for each of the plurality of combinations, and the information transmitted from the plurality of combinations and the surge propagation speed. It is provided with a first diagnosis unit and 512, which diagnoses whether or not a ground fault point exists inside a predetermined area R1 based on a plurality of derived distances.

Further, when the ground fault point locating device 500 positions the ground fault point using three measuring terminals 400 (400A to 400C) installed across the branch point, the first calculation unit 511 has three units. Three distances are derived based on the information transmitted from the combination of three of the measurement terminals 400 and the three measurement terminals 400 and the surge propagation speed.

Then, the first diagnosis unit 512 is when two of the three distances are outside the predetermined sphere R1 and the remaining one is inside the predetermined sphere R1. , Diagnose that the ground fault point exists outside the predetermined area. On the other hand, the first diagnosis unit 512 diagnoses that the ground fault point exists inside the predetermined category R1 when all three distances exist inside the predetermined category R1.

Further, in the case where the ground fault point locating device 500 positions the ground fault point using four measuring terminals 400 (400A to 400D) installed across the branch point.
The first calculation unit 511 derives six distances based on the information transmitted from the six combinations including any two measurement terminals 400 out of the four measurement terminals 400 and the surge propagation speed.

Then, in the first diagnosis unit 512, three of the six distances are outside the predetermined sphere R1 centered on the branch point, and the remaining three distances are in the predetermined sphere R1. If it exists inside, it is diagnosed that the ground fault point exists outside the predetermined category R1. On the other hand, the first diagnosis unit 512 diagnoses that the ground fault point exists inside the predetermined category R1 when all six distances exist inside the predetermined category R1 centered on the branch point. ..

Further, the discriminating unit 510 is a speed value of the surge propagation speed that can be arbitrarily set, and is an initial value storage unit 513 that stores the initial value of the surge propagation speed used when the first calculation unit 511 first performs the calculation. If it is possible to determine whether or not it exists inside the predetermined sphere R1 based on the distance derived by performing the calculation by the first calculation unit 511 using the initial value, the value other than the initial value is obtained. Is not performed by the first diagnostic unit 512 using the surge propagation velocity.

On the other hand, when the discrimination unit 510 cannot determine whether or not it exists inside the predetermined category R1 based on the distance derived by performing the calculation by the first calculation unit 511 using the initial value. In addition, another calculation is performed by the first diagnostic unit 512 using a value other than the initial value as the surge propagation speed.

Further, the discrimination unit 510 performs an calculation by the first calculation unit 511 using a plurality of surge propagation velocities, and the ground fault point is a predetermined area based on the diagnosis result of the first diagnosis unit 512 based on the derived distance. A second diagnosis unit 519 for determining whether or not it exists inside R1 is provided, and the second diagnosis unit 519 can determine whether or not the ground fault point exists inside a predetermined area R1. When there are a plurality of surge propagation velocities, the diagnostic result of the first diagnostic unit 512 when the surge propagation velocity having the smallest difference from the initial value is used among the plurality of surge propagation velocities is obtained by the second diagnostic unit 519. It is the diagnosis result of.

It should be noted that the above embodiment is for facilitating the understanding of the present invention, and is not for limiting and interpreting the present invention. The present invention can be modified and improved without departing from the spirit thereof, and the present invention also includes an equivalent thereof.

100 Ground fault point locating system 200, 200A, 200B Distribution wire 310 Current sensor 320 Voltage sensor 400, 400A, 400B, 400C, 400D Measuring terminal 500 Ground fault point locating device 510 Pattern determination unit 511 First calculation unit 512 First diagnosis unit 513 Initial value storage unit 514 Speed value generation unit 515 Speed setting unit 516 Speed condition storage unit 517 Speed condition judgment unit 518 Diagnosis result storage unit 319 Second diagnosis unit 520 Positioning unit 521 First calculation unit 522 Second calculation unit 523 Speed condition Storage unit 524 Speed condition determination unit 525 Third calculation unit 526 Localization result output unit 530 Localization unit 537 Fourth calculation unit 600 Prop 700 GPS satellite 800 Switch 800A Storage box

Claims (18)

Multiple measurement terminals installed across a branch point on a distribution line that includes a branch,
A ground fault locating device that is communicatively connected to the plurality of measurement terminals,
Consists of, including
The plurality of measuring terminals indicate the current time of information indicating the zero-phase current and the zero-phase voltage output from the sensor that detects the current and voltage of the distribution line when a ground fault occurs in the distribution line. The information associated with the information is transmitted to the ground fault locating device, and the information is transmitted.
The ground fault point locating device is based on the information transmitted from the combination of the measurement terminals of any two of the three or more measurement terminals installed across the branch point, and the surge propagation speed. To determine the ground fault point of the distribution line,
It is a ground fault point positioning system,
The ground fault point locator is
A ground fault point locating system characterized in that it is provided with a discriminating unit for discriminating whether or not the ground fault point exists inside a predetermined sphere centered on a branch point of the distribution line. The ground fault point locator is
Further provided with a locating unit for locating the ground fault point based on the information, the surge propagation velocity, and the discrimination result of the discriminating unit.
The locating unit changes the locating method of the ground fault point according to the discrimination result of the discriminating unit.
The ground fault locating system according to claim 1, wherein the ground fault locating system is characterized in that. The discriminating unit
Based on the information transmitted from a plurality of combinations consisting of any two of the three or more measurement terminals and the surge propagation speed, each of the plurality of combinations is from a predetermined measurement terminal. The first arithmetic unit that derives the distance and
Based on the plurality of distances derived based on the information transmitted from the plurality of combinations and the surge propagation velocity, it is diagnosed whether or not the ground fault point exists inside the predetermined sphere. One diagnostic department and
The ground fault locating system according to claim 1 or 2, wherein the ground fault locating system is provided. In the case where the ground fault point locating device defines the ground fault point using the three measuring terminals installed across the branch point.
The first calculation unit derives the three distances based on the information transmitted from the combination of the three measurement terminals of any two of the three measurement terminals and the surge propagation speed.
The ground fault locating system according to claim 3, wherein the ground fault locating system is characterized in that. The first diagnostic unit
When two of the three distances are outside the predetermined area and the remaining one is inside the predetermined area, the ground fault point is located. Diagnose that it exists outside the predetermined category,
The ground fault locating system according to claim 4, wherein the ground fault locating system is characterized in that. The first diagnostic unit
When all of the three distances are inside the predetermined category, it is diagnosed that the ground fault point is inside the predetermined category.
The ground fault locating system according to claim 4, wherein the ground fault locating system is characterized in that. In the case where the ground fault point locating device defines the ground fault point using the four measuring terminals installed across the branch point.
The first calculation unit derives the six distances based on the information transmitted from the six combinations of any two of the four measurement terminals and the surge propagation speed.
The ground fault locating system according to claim 3, wherein the ground fault locating system is characterized in that. The first diagnostic unit
When three of the six distances are outside the predetermined sphere centered on the branch point, and the remaining three distances are inside the predetermined sphere. , Diagnose that the ground fault point exists outside the predetermined sphere.
The ground fault locating system according to claim 7, characterized in that. The first diagnostic unit
When all of the six distances are inside a predetermined area centered on the branch point, it is diagnosed that the ground fault point is inside the predetermined area.
The ground fault locating system according to claim 7, characterized in that. The discriminating unit
It is provided with an initial value storage unit that stores an initial value of the surge propagation speed that can be arbitrarily set and is used when the first calculation unit performs an operation for the first time.
When it is possible to determine whether or not the product exists inside the predetermined sphere based on the distance derived by performing the calculation by the first calculation unit using the initial value, the value other than the initial value is obtained. Is not performed by the first diagnostic unit using the above as the surge propagation velocity.
The ground fault locating system according to any one of claims 3 to 9, wherein the ground fault locating system is characterized in that. The discriminating unit
When it is not possible to determine whether or not the product exists inside the predetermined sphere based on the distance derived by performing the calculation by the first calculation unit using the initial value, the initial value is used. Other calculations are performed by the first diagnostic unit using other than as the surge propagation velocity.
The ground fault locating system according to claim 10. The discriminating unit performs an operation by the first arithmetic unit using the plurality of surge propagation velocities, and the ground fault point is determined based on the diagnosis result of the first diagnostic unit based on the derived distance. Equipped with a second diagnostic unit that determines whether or not it exists inside the sphere
When there are a plurality of the surge propagation velocities capable of determining whether or not the ground fault point exists inside the predetermined sphere, the second diagnostic unit is among the plurality of the surge propagation velocities. ,
The diagnostic result of the first diagnostic unit when the surge propagation speed having the smallest difference from the initial value is used is used as the diagnostic result of the second diagnostic unit.
11. The ground fault point determination system according to claim 11. A ground fault locator that is communicably connected to a plurality of measuring terminals installed across a branch point on a distribution line including a branch.
The plurality of measuring terminals indicate the current time of information indicating the zero-phase current and the zero-phase voltage output from the sensor that detects the current and voltage of the distribution line when a ground fault occurs in the distribution line. The information associated with the information is transmitted to the ground fault locating device, and the information is transmitted.
The ground fault point locating device is based on the information transmitted from the combination of the measurement terminals of any two of the three or more measurement terminals installed across the branch point, and the surge propagation speed. Then, determine the ground fault point of the distribution line,
The ground fault point locator is
A discriminant unit for determining whether or not the ground fault point exists inside a predetermined sphere centered on the branch point of the distribution line is provided.
A ground fault point locator characterized by this. Further provided with a locating unit for locating the ground fault point based on the information, the surge propagation velocity, and the discrimination result of the discriminating unit.
The locating unit changes the locating method of the ground fault point according to the discrimination result of the discriminating unit.
The ground fault point locating device according to claim 13. It is a method of locating a ground fault point locating device that is communicably connected to a plurality of measuring terminals installed across a branch point on a distribution line including a branch.
The plurality of measuring terminals indicate the current time of information indicating the zero-phase current and the zero-phase voltage output from the sensor that detects the current and voltage of the distribution line when a ground fault occurs in the distribution line. The information associated with the information is transmitted to the ground fault locating device, and the information is transmitted.
The ground fault point locating device is based on the information transmitted from the combination of the measurement terminals of any two of the three or more measurement terminals installed across the branch point, and the surge propagation speed. Then, determine the ground fault point of the distribution line,
The ground fault point locator is
A determination step for determining whether or not the ground fault point exists inside a predetermined sphere centered on the branch point of the distribution line is provided.
A method for locating a ground fault point locating device. Further provided with a locating step of locating the ground fault point based on the information, the surge propagation velocity, and the discrimination result in the discrimination step.
In the locating step, the locating method of the ground fault point is changed according to the discrimination result of the discrimination unit.
The ground fault point locating device according to claim 15, characterized in that. When a ground fault occurs in the distribution line by being communicably connected to a plurality of measurement terminals installed across the branch point on the distribution line including the branch, the current of the distribution line and the current of the distribution line are transmitted from the plurality of measurement terminals. A computer that constitutes a ground fault point locator that defines a ground fault point by receiving information indicating the zero-phase current and zero-phase voltage output from a sensor that detects voltage in association with information indicating the current time. To,
Ground fault of the distribution line based on the information transmitted from the combination of any two of the three or more measurement terminals installed across the branch point and the surge propagation speed. A program that realizes a locating function for locating points. The ground fault point is determined on the computer based on the surge propagation speed and the determination result of whether or not the ground fault point exists inside a predetermined sphere centered on the branch point of the distribution line. Further realize the localization function to be performed,
The positioning function changes the positioning method of the ground fault point according to the determination result.
The program according to claim 17.

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