JP2019207176A - Detection device, method, and program - Google Patents

Abstract

To provide a detection device capable of identifying a state of an electric line to be measured from an analysis result by analyzing a leakage current.SOLUTION: A detection device includes: a leakage current detection part 11 for detecting a leakage current flowing to an electric line to be measured; a voltage detection part 12 for detecting voltage applied between two phase of the electric line to be measured; a phase difference detection part 13 for detecting a phase difference on the basis of a leakage current detected by the leakage current detection part 11 and voltage detected by the voltage detection part 12; and an identification part 14 for showing a leakage current by a vector by disposing the leakage current detected by the leakage current detection part 11 in a position on coordinates fixed by a phase difference detected by the phase difference detection part 13, analyzing a change amount of vectors of at least two leakage currents, and identifying a state of the electric line to be measured on the basis of the analysis result.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a detection device, a method, and a program for detecting a state of a measured electrical line.

  The use of electricity is convenient, but if it is not properly managed and used, it has very dangerous aspects, and there are many possibilities of causing serious accidents such as electric fires and electric shocks.

For example, as one of the causes of the serious accident, the leakage current I ₀ is deeply related to the insulation failure of the electric circuit and equipment. Here, the leakage current I ₀ includes a leakage current caused by the ground capacitance and a leakage current caused by the ground insulation resistance that is directly involved in the insulation resistance. The leakage current caused by the ground capacitance is referred to as “I ₀ c”, but may be referred to as “Igc”. In this embodiment, the leakage current resulting from the ground insulation resistance is referred to as “I ₀ c”. Further, the leakage current resulting from the ground insulation resistance is sometimes referred to as “I ₀ r” or “I 0r”, but may also be referred to as “Igr”. In this embodiment, the leakage current resulting from the ground insulation resistance is referred to as “I ₀ r” or “I ₀ r”. The cause of the electric fire described above is the presence of insulation resistance. Therefore, if only I ₀ r can be detected accurately, the insulation state of the circuit can be checked, and catastrophic events such as a leakage fire can be avoided.

For example, in Patent Document 1, a CT sensor unit that clamps the entire measured electrical line A and detects a leakage current I ₀ flowing in the measured electrical line A, and a voltage that detects the voltage of the measured electrical line A Based on the detection unit, the leakage current I ₀ and the voltage of the measured electrical line A, the phase pulse width measuring unit that measures the phase pulse width, and the power supply frequency is measured based on the voltage of the measured electrical line A The phase angle for calculating the phase angle of the leakage current I ₀ flowing through the line A to be measured from the power source frequency measured by the power source frequency measuring unit, the phase pulse width measuring unit, and the power source frequency measured by the power source frequency measuring unit. beyond a calculation unit, and the phase angle of the leakage current I ₀ which is calculated by the phase angle calculator, on the basis of the leakage current I _0, and the leakage current calculator for calculating the I 0 _r, I 0 _r is a predetermined value Of the judgment part that judges whether or not Based on the cross, the leakage current cutoff device including a blocking portion for blocking the measured electric line is disclosed.

Japanese Patent No. 4159590

However, analyzing the leakage current I _0, knowing the measured electric line is in what state from the analysis results, or measurement as needed under measurement electric line, or everyday It is important for monitoring.

It is an object of the present invention to provide a detection device, method, and program capable of analyzing the leakage current I ₀ and identifying the state of the measured electrical line from the analysis result.

  In order to achieve the above object, the detection device according to one aspect of the present invention is a three-phase circuit in which three phases (R phase, S phase, T phase) are Δ-connected, one of the phases is grounded, and a ground wire is drawn out. In the detection device for detecting the state of the three-wire type measured electric line, a leakage current detecting unit for detecting a leakage current flowing in the measured electric line and between any two phases of the measured electric line A voltage detection unit for detecting the applied voltage; a phase difference detection unit for detecting a phase difference based on the leakage current detected by the leakage current detection unit and the voltage detected by the voltage detection unit; By arranging the leakage current detected by the leakage current detection unit at a position on the coordinates defined by the phase difference detected by the phase difference detection unit, the leakage current is indicated by a vector, and at least two leakage currents Solve vector change And, based on the analysis result, the includes a specifying unit for specifying a state of the measured electric line.

  In addition, the detection method according to one embodiment of the present invention is a three-phase three-wire type measurement target in which three phases (R phase, S phase, and T phase) are Δ-connected, one of the phases is grounded, and a ground wire is drawn out. In the detection method for detecting the state of the electric line, a leakage current detecting step for detecting a leakage current flowing in the electric line to be measured and a voltage applied between any two phases of the electric line to be measured A voltage detection step for detecting, a phase difference detection step for detecting a phase difference based on the leakage current detected by the leakage current detection step and the voltage detected by the voltage detection step, and the phase difference detection step By placing the leakage current detected by the leakage current detection process at a position on the coordinates defined by the detected phase difference, the leakage current is indicated by a vector, and the change in the vector of at least two leakage currents is analyzed And Based on the analysis result includes a specifying step of specifying the state of the measured electric line.

  In addition, the detection program according to one aspect of the present invention is a three-phase three-wire system to be measured in which three phases (R phase, S phase, T phase) are Δ-connected, one of the phases is grounded, and a ground wire is drawn out. In the detection program for detecting the state of the electric line, a leakage current detecting step for detecting a leakage current flowing in the electric line to be measured and a voltage applied between any two phases of the electric line to be measured A voltage detection step for detecting, a phase difference detection step for detecting a phase difference based on the leakage current detected by the leakage current detection step and the voltage detected by the voltage detection step, and the phase difference detection step By arranging the leakage current detected by the leakage current detection step at a position on the coordinates defined by the detected phase difference, the leakage current is indicated by a vector, and the change in the vector of at least two leakage currents Analyzes, based on the analysis result, the a program for implementing by a specifying step of specifying the state of the measured electric line, a computer.

According to the present invention, it is possible to analyze the leakage current I _0, to identify whether the measured electric line is in any state from the results of this analysis.

It is a figure which shows the structure of a detection apparatus. It is a figure which shows the structure of a detection part. It is a figure where it uses for description about operation | movement of a specific part. It is a figure where it uses for description about the (DELTA) connection system concerning this invention. It is a diagram for explaining the relationship between the leakage current and I _{0 r} in the case of a one-phase ground fault in the T-phase. It is a diagram for explaining the relationship between the leakage current and I _{0 r} in the case of a one-phase ground fault of R-phase. It is a figure where it uses for description about the case where an electrostatic capacitance generate | occur | produces only in the R phase and a ground fault occurs only in the T phase. It is a figure which shows the result of 1st experiment in case a ground capacitance is in an unbalanced state. It is a figure which shows the result of the 2nd experiment in case a ground capacitance is an unbalanced state. It is a figure which shows the result of 3rd experiment in case a ground electrostatic capacitance is an unbalanced state. It is a figure where it uses for description about the case where an electrostatic capacitance and a ground fault generate | occur | produce only in the T phase. It is a figure which shows the result of the 4th experiment in case a ground electrostatic capacitance is in an unbalanced state. It is a figure which shows the result of 5th experiment in case a ground electrostatic capacitance is an unbalanced state. It is a figure which shows the result of 6th experiment in case a ground electrostatic capacitance is an unbalanced state. It is a first diagram for explaining the computing equation derived for calculating the I 0 _r. It is a second diagram for explaining the computing equation derived for calculating the I 0 _r. It is a flowchart with which it uses for description about operation | movement of a detection apparatus.

  Hereinafter, this embodiment will be described. In addition, this embodiment demonstrated below does not unduly limit the content of this invention described in the claim. In addition, all the configurations described in the present embodiment are not necessarily essential configuration requirements of the present invention.

The detection device 1 corresponds to a three-phase three-wire connection method (so-called Δ connection method) in which three phases are Δ-connected and one of the three phases is grounded, and is a device that detects the state of the measured electrical line. It is. In particular, the detection device 1 can be easily and safely from the outside without causing the power circuit and mechanical equipment to be in a power failure state for detection and without destroying the function of the equipment connected to the measured electrical line. It has a function of accurately detecting the resistance component leakage current caused by the ground insulation resistance directly related to the quality of insulation and notifying the outside that the resistance component leakage current exceeds a predetermined value. Moreover, the detection apparatus 1 may function as a monitoring apparatus which monitors the state of a to-be-measured electrical line on a daily basis, or the state of the to-be-measured electrical line is changed regularly or irregularly as needed. It may function as a measuring device for measuring. The resistance component leakage current resulting from the ground insulation resistance is sometimes referred to as “I ₀ r” or “I0r”, but may also be referred to as “Igr”. In this embodiment, the resistance component leakage current resulting from the ground insulation resistance is referred to as “I ₀ r” or “I ₀ r”.

  Below, the specific structure of the detection apparatus 1 is demonstrated. As illustrated in FIG. 1, the detection device 1 includes a detection unit 10, a determination unit 20, and a notification unit 30.

  The detection unit 10 detects the insulation state of a three-phase three-wire type measured electrical line in which three phases (R phase, S phase, T phase) are Δ-connected, and one of the phases is grounded and a ground wire is drawn out. To do.

The notification unit 30 notifies the detection information from the detection unit 10 to the outside. For example, the notification unit 30 outputs insulation information including I ₀ r to the display.

The detection information, and the leakage current I _0, and I _{0 r} which is being included in the leakage current I _0, and the phase difference (phase angle), and the reference voltage, the insulation resistance value (Gr) and, includes temperature and ing. The detection information may also include a capacitance component leakage current caused by the ground capacitance. In addition, although the electrostatic capacitance component leakage current resulting from the ground capacitance is referred to as “I ₀ c”, it may be referred to as “Igc”. In this embodiment, the capacitance component leakage current caused by the ground insulation resistance is referred to as “I ₀ c”.

I ₀ c is a component that not only increases in capacity according to the length of the electric wire to be measured, but also increases in capacity due to harmonic distortion current caused by inverters, noise filters, etc. used in electrical equipment. is there. The detection device 1 performs detection at a predetermined time interval (for example, 250 msec).

Leakage current I ₀ is the sum (vector sum) of I ₀ r and I ₀ c. I ₀ c is a component that not only increases in capacity according to the length of the electric wire to be measured, but also increases in capacity due to harmonic distortion current caused by inverters, noise filters, etc. used in electrical equipment. is there. The detection device 1 can accurately calculate I ₀ r that causes an electric fire or the like from the leakage current I ₀ .

The determination unit 20 determines whether or not I ₀ r included in the detection information by the detection unit 10 exceeds a predetermined value. The predetermined value is, for example, 10 mA.

When the determination unit 20 determines that I ₀ r exceeds a predetermined value, the notification unit 30 notifies the outside that I ₀ r exceeds a predetermined value.

<Regarding Configuration and Operation of Notification Unit 30>
The notification unit 30 includes a terminal for serial communication (for example, RS-485) and a terminal for LAN connection. When the sequencer is connected to the serial communication terminal and I ₀ r exceeds a predetermined value, the sequencer Patlite (registered trademark) lights up. The operator can recognize that I ₀ r exceeds a predetermined value by turning on the patrol light, and can take necessary measures.

  Further, the notification unit 30 can transmit data to a terminal device (such as a smartphone or a personal computer) connected to the network via the LAN connection terminal. It is assumed that an application that can receive the detection information transmitted from the detection device 1 and display it in a predetermined form is installed in the terminal device.

  In normal times, the detection device 1 periodically transmits detection information to the terminal device via the notification unit 30. Note that a pull-type configuration in which the detection information is acquired by operating the application of the terminal device to access the detection device 1 may be used.

  Therefore, the operator of the terminal device can always grasp the state of the electric circuit and the load device in the place (factory or the like) where the detection device 1 is installed.

Further, when an abnormality occurs (when I ₀ r exceeds a predetermined value), the detection device 1 informs the terminal device via the notification unit 30 that I ₀ r exceeds the predetermined value. Send.

For example, when an electrical facility manager is not in a factory in a local factory (especially at midnight, etc.), an operator of a terminal device located remotely via a network recognizes an abnormal value of I ₀ r, You can take the necessary steps.

Furthermore, the detection apparatus 1 can detect how much value I ₀ r is generated in which load, and can notify the outside.

Further, the determination unit 20 may have a function of collecting information detected by the detection unit 10 over time and, for example, predicting that I ₀ r exceeds a set value. According to this configuration, the detection device 1, even though it is not beyond the I _{0 r} set value, can predict that in the near future I _{0 r} may exceed the set value, to improve the service Can do.

<About the structure and operation | movement of the detection part 10>
Next, a specific configuration of the detection unit 10 will be described. The detection unit 10 corresponds to the Δ connection method, and as illustrated in FIG. 2, the leakage current detection unit 11, the voltage detection unit 12, the phase difference detection unit 13, the identification unit 14, and the resistance component leakage current calculation unit. 15 and a correction unit 16.

The leakage current detector 11 detects the leakage current I ₀ flowing in the measured electric wire path. Specifically, the leakage current detection unit 11 uses the clamp unit 100 to clamp the measured electric wire and detects the leakage current flowing through the measured electric wire. In addition, although the clamp part 100 has shown the form which clamps the whole to-be-measured electric wire collectively in FIG. 2, it is not restricted to this, It is the structure which selectively pinches the electric wire which comprises a to-be-measured electric wire. There may be a configuration in which the electric wires constituting the electric wire to be measured are selectively sandwiched one by one.

  Further, the leakage current detection unit 11 calculates an effective value of the detected leakage current. The leakage current detection unit 11 outputs the calculated effective value of the leakage current to the phase difference detection unit 13, the specification unit 14, the resistance component leakage current calculation unit 15, and the correction unit 16.

  The voltage detector 12 detects a voltage applied between any two phases of the electric wire to be measured. In the example shown in FIG. 2, since the S phase is grounded, the voltage detection unit 12 detects a voltage applied between the R phase and the T phase. Note that the phase to be grounded is not limited to the S phase.

  The phase difference detection unit 13 detects the phase difference θ based on the leakage current detected by the leakage current detection unit 11 and the voltage detected by the voltage detection unit 12 (hereinafter referred to as “reference voltage”). Specifically, the phase difference detection unit 13 detects the phase difference θ between the reference voltage and the leakage current based on the point where the reference voltage crosses zero and the point where the leakage current crosses zero.

  The specifying unit 14 arranges the leakage current detected by the leakage current detection unit 11 at a position on the coordinates defined by the phase difference detected by the phase difference detection unit 13 to indicate the leakage current as a vector, The change in the vector of the two leakage currents is analyzed, and the state of the line to be measured is specified based on the analysis result.

The resistance component leakage current calculation unit 15 is configured to detect leakage flowing in the measured electrical line based on the phase difference detected by the phase difference detection unit 13 and the effective value of the leakage current detected by the leakage current detection unit 11. I ₀ r included in the current is calculated.

Based on the phase difference θ detected by the phase difference detection unit 13 and the effective value (I ₀ ) of the leakage current detected by the leakage current detection unit 11, the resistance component leakage current calculation unit 15 I ₀ r included in the flowing leakage current is calculated by equation (1). A method for deriving the expression (1) will be described later.
I ₀ r = I ₀ × sin θ / cos (π / 6) (1)

Further, the resistance component leakage current calculation unit 15 calculates an insulation resistance value (Gr) by the equation (2) based on the reference voltage and I ₀ r.
Gr = V / I ₀ r (2)

In addition, the determination unit 20 determines whether or not I ₀ r calculated by the resistance component leakage current calculation unit 15 exceeds a predetermined value.

<About the operation of the specifying unit 14 (1)>
Here, the operation of the specifying unit 14 will be described. As shown in FIG. 3, the specifying unit 14 detects the first leakage detected last time by the leakage current detecting unit 11 at a position on the coordinates defined by the first phase difference θ ₀₁ detected last time by the phase difference detecting unit 13. The first vector I ₀₁ obtained by arranging the current and the second current difference θ ₀₂ detected this time by the phase difference detector 13 and the current position detected by the leakage current detector 11 at a position on the coordinates defined by the current phase. A third vector I ₀₃ (second vector I _{02 -first} vector I ₀₁ ) that is a difference from the second vector I ₀₂ obtained by arranging two leakage currents is calculated, and an angle θ formed by the third vector I ₀₃ Based on ₀₃ , the ground fault phase is specified.

In the example shown in FIG. 3, the coordinates of the end point of the first vector I ₀₁ are (x1, y1), and the coordinates of the end point of the second vector I ₀₂ are (x2, y2). Starting point of the coordinates of the third vector _{I 03} is the end point of the coordinates of the first vector _{I 01} (x1, y1).

Details are described in Japanese Patent No. 4159590, but the R phase I ₀ r occurs at a position of 60 degrees from the reference point, and the T phase I ₀ r at a position of 120 degrees from the reference point. Occur.

When the angle θ ₀₃ formed by the third vector I ₀₃ is 60 degrees, the specifying unit 14 specifies that a ground fault has occurred in the R phase. Further, the specifying unit 14 specifies that the ground fault has occurred in the T phase when the angle θ ₀₃ formed by the third vector I ₀₃ is 120 degrees.

  The information specified by the specifying unit 14 is notified to the terminal device via the notification unit 30. The operator of the terminal device can confirm the ground fault phase based on the ground fault phase information and can take necessary measures such as maintenance.

<When the capacitance to ground is in equilibrium>
Here, the Δ connection method (hereinafter referred to as “I ₀ r method”) according to the present invention will be described. In the Y connection method, if the I ₀ c components of each phase are balanced, I ₀ c is canceled and becomes zero. However, in the Δ connection method, when the S phase is grounded, the S phase has a zero potential, and I ₀ c is not generated in the S phase. That is, I ₀ c is generated in the R phase and the T phase having the ground potential and is not canceled out.

When I ₀ c having the same magnitude is generated in the R phase and the T phase, if I ₀ c of the R phase is I ₀ c (r) and I ₀ c of the T phase is I ₀ c (t) As shown in FIG. 4, the vector synthesis generates I ₀ c (rt) synthesized at a position of 180 degrees with reference to the phase voltage V _R−T (R → T) between the R phase and the T phase. .

Further, the vector combination of I ₀ c (rt) and I ₀ r (r) generated in the R phase or / and I ₀ r (t) generated in the T phase becomes the leakage current I ₀ .

For example, in the case of a T-phase one-phase ground fault, as shown in FIG. 5, the vector combination of I ₀ r (t) and I ₀ c (rt) becomes the leakage current I ₀ . The leakage current I ₀ varies with the variation of I ₀ c (rt). As an example, in a situation where I ₀ c (rt) of about 107 mA is generated, when I ₀ r (t) of about 100 mA is generated in the T phase, the leakage current I ₀ as a vector sum is about 180 mA. . In such cases, tends to increase the leakage current I _0, it is possible also detected in the conventional method referred to as I0 scheme. However, in the R phase, the relationship is greatly different.

Here, in the case of an R-phase one-phase ground fault, as shown in FIG. 6, the vector combination of I ₀ r (r) and I ₀ c (rt) becomes the leakage current I ₀ . That is, unlike the case of the T-phase one-phase ground fault, in the case of the R-phase one-phase ground fault, the leakage current I ₀ is smaller than I ₀ c (rt). For example, in a situation where I ₀ c (rt) of about 107 mA is generated, when I ₀ r (r) of about 100 mA is generated in the R phase, the leakage current I ₀ as a vector sum is about 104 mA. _It becomes smaller than 0c (rt). That is, in the Δ connection method, “I ₀ > I ₀ r (t)” is obtained in the T phase, and “I ₀ <I ₀ r (r)” is obtained in the R phase.

For example, in the I0 method, in the case of setting to notify when a leakage current of 30 mA or more is generated, 10 mA I ₀ c (rt) is generated, and 30 mA I ₀ r (r) There also be generated, leakage current I _0, in order to show the degree of 26 mA, as set above leakage current is not generated, it is possible that no notification. In the I0 system, a dangerous state in the R phase may be missed.

On the other hand, the detection unit 10 that employs the I ₀ r method can accurately detect I ₀ r (r) even in the case of a one-phase ground fault of the R phase, so that a dangerous state in the R phase is not overlooked. There are advantages.

When the ground capacitance in the I ₀ r method is in an equilibrium state (balance), I ₀ r calculated by the resistance component leakage current calculation unit 15 is an unbalanced state (unbalance) in the ground capacitance. Does not include an error (virtual I ₀ r, described later).

<When the ground capacitance is in an unbalanced state>
When the capacitance (I ₀ c) is unbalanced (unbalanced), I ₀ r calculated based on the equation (1) includes an error. That is, I ₀ r is larger or smaller than the actual value. In particular, if I ₀ r is less than the actual value, the fact is that the accident should be eliminated, but the fact is not notified to the electrical chief engineer, and there are security concerns. Can occur.

<About the operation of the specifying unit 14 (2)>
The specifying unit 14 is obtained by arranging the first leakage current detected by the leakage current detection unit 11 at a position on the coordinates defined by the first phase difference θ ₀₁ detected by the phase difference detection unit 13. A second obtained by arranging the second leakage current detected by the leakage current detection unit 11 at a position on the coordinates defined by the vector I ₀₁ and the second phase difference θ ₀₂ detected by the phase difference detection unit 13. the third vector _{I 03} (second vector _{I 02} - first vector _{I 01)} which is the difference between the vector _{I 02} calculates, based on the angle theta ₀₃ of the third vector _{I 03,} the two ungrounded It is specified whether the ground capacitance flowing in each phase is in an equilibrium state or an unbalanced state.

Although details will be described later, the R-phase ground capacitance (I ₀ c (r)) occurs at a position 90 degrees from I ₀ r (r), that is, a position 150 degrees from the reference point. The T-phase ground capacitance (I ₀ c (t)) is generated at a position 90 degrees from I ₀ r (t), that is, at a position 210 degrees from the reference point. In addition, when the ground capacitance is generated in the R phase and the T phase, and the ground capacitance is in an equilibrium state, the ground phase capacitance (I ₀ c (r)) of the R phase and the ground level of the T phase are static. The ground capacitance (I ₀ c (rt)) combined with the capacitance (I ₀ c (t)) is generated at a position of 180 degrees from the reference point.

For example, when the angle θ ₀₃ formed by the third vector I ₀ 3 is 180 degrees, the specifying unit 14 determines that the ground capacitance is in an equilibrium state. The identifying unit 14 determines that the ground capacitance is in an unbalanced state when the angle θ ₀₃ formed by the third vector I ₀₃ is 150 degrees or 210 degrees.

The information specified by the specifying unit 14 is notified to the terminal device via the notification unit 30. If the ground capacitance is in an equilibrium state, the operator of the terminal device can determine that I ₀ r calculated by the resistance component leakage current calculation unit 15 is an accurate value, and the ground capacitance is If it is an unbalanced state, it can be determined that I ₀ r calculated by the resistance component leakage current calculation unit 15 is not an accurate value, and necessary measures can be taken.

<About the operation of the specifying unit 14 (3)>
When the specifying unit 14 specifies that the ground capacitances flowing in the two phases that are not grounded are in an unbalanced state, the resistance component leakage current calculated by the resistance component leakage current calculation unit 15 is an excessive value. Specify whether it is or is too small.

Although details will be described later, when the R-phase ground capacitance (I ₀ c (r)) is larger than the T-phase ground capacitance (I ₀ c (t)), a resistance component leakage current calculation unit I ₀ r calculated by 15 is an excessive value than the actual value. When the T-phase ground capacitance (I ₀ c (t)) is larger than the R-phase ground capacitance (I ₀ c (r)), the resistance component leakage current calculation unit 15 calculates the value. In addition, I ₀ r is a value that is less than the actual value.

For example, when the angle θ ₀₃ formed by the third vector I ₀₃ is smaller than 180 degrees, the specifying unit 14 determines that the R-phase ground capacitance is larger than the T-phase ground capacitance (I ₀ c (t)). Since the capacity (I ₀ c (r)) is large, it is determined that I ₀ r calculated by the resistance component leakage current calculation unit 15 is an excessive value than the actual value. In addition, when the angle θ ₀₃ formed by the third vector I ₀₃ is larger than 180 degrees, the specifying unit 14 determines that the T-phase ground capacitance is larger than the R-phase ground capacitance (I ₀ c (r)). Since the capacitance (I ₀ c (t)) is large, it is determined that I ₀ r calculated by the resistance component leakage current calculation unit 15 is a value smaller than the actual value.

The information specified by the specifying unit 14 is notified to the terminal device via the notification unit 30. If the operator of the terminal device knows that I ₀ r notified by the notification unit 30 is an excessive value than the actual value, the operator of the terminal device should take necessary measures (for example, do not stop the load operation). Can do.

Further, if the operator of the terminal device knows that I ₀ r notified by the notification unit 30 is a value that is less than the actual value, the operator of the terminal device can use necessary means (for example, stop the load operation). Can be taken.

<Operation of Correction Unit 16>
The correcting unit 16 has an unbalanced ground capacitance flowing through two phases that are not grounded by the specifying unit 14, and the resistance component leakage current calculated by the resistance component leakage current calculation unit 15 is an excessive value. In the case where it is determined that this is, the excessive value is calculated, and the calculated excessive value is subtracted from the resistance component leakage current calculated by the resistance component leakage current calculation unit 15. The correction unit 16 outputs the corrected I ₀ r obtained by subtracting an excessive value to the determination unit 20.

Further, the correction unit 16 has an unbalanced ground capacitance flowing through two phases that are not grounded by the specifying unit 14, and the resistance component leakage current calculated by the resistance component leakage current calculation unit 15 is too small. When it is determined that the value is a small value, the undervalue is calculated, and the calculated undervalue is added to the resistance component leakage current calculated by the resistance component leakage current calculation unit 15. The correction unit 16 outputs the corrected I ₀ r obtained by adding the excessive value to the determination unit 20.

Therefore, the detection apparatus 1 can make a determination based on the corrected I ₀ r, and can make a correct determination even when the ground capacitance is in an unbalanced state.

<When R Phase Ground Capacitance (I ₀ c (r)) is More Than T Phase Ground Capacitance (I ₀ c (t))>
_Here, in the case than _{I 0 c (t) I 0} c (r) is _large, I 0 c (t) and _I 0 vector synthesis of _{c (r) I 0 c (} rt) is 180 degrees Occurs at smaller angle positions. In this case, I ₀ r calculated by the calculation is obtained by adding a component caused by the unbalance of the capacitance to the resistance component leakage current caused by the actual ground insulation resistance, thereby causing the resistance component leakage caused by the actual ground insulation resistance. The value is larger than the current. Hereinafter, a component generated due to capacitance imbalance is referred to as “virtual I ₀ r”. The virtual I ₀ r can be calculated from the equation (1).

  Here, a case where capacitance occurs only in the R phase and a ground fault occurs only in the T phase will be considered with reference to FIG.

Note that I ₀ c when the electrostatic capacities generated in the R phase and the T phase are equal and the electrostatic capacities are in equilibrium is I ₀ c (1). I ₀ c (1) occurs at an angle of π (180 degrees) as shown in FIG.

Further, let I ₀ c be I ₀ c (2) when capacitance occurs only in the R phase and the capacitance is unbalanced. I ₀ c (2) occurs at an angle of 5π / 6 (150 degrees) as shown in FIG.

Further, since a ground fault occurs only in the T phase, I ₀ r is set to I ₀ r (1). I ₀ r (1) occurs at an angle of 2π / 3 (120 degrees) as shown in FIG.

In the case where the capacitance is _balanced, the I 0 c (1) and _I 0 r (1) and _{I 0} obtained by combining the _I 0 that (T1). In the state where the capacitance is balanced, the virtual I ₀ r is not included in the I ₀ r calculated by the equation (1).

On the other hand, when the electrostatic capacitance is _unbalanced, the I 0 c (2) and _I 0 r (1) and _{I 0} obtained by combining the _I 0 that (T2). In the state of the capacitance unbalance, the I _{0 r} calculated by equation (1) includes a virtual I _{0 r.}

Therefore, even if the magnitude of I ₀ c is the same as the magnitude of I ₀ , if the capacitance is in an unbalanced state, I ₀ r calculated by equation (1) is a value obtained by adding virtual I ₀ r It is over the value that actually occurs.

  The same applies to the case where capacitance occurs only in the R phase and a ground fault occurs only in the R phase.

  Here, FIG. 8 to FIG. 10 show experimental results when the ground capacitance is in an unbalanced state. FIG. 8 shows the results of the first experiment. FIG. 9 shows the results of the second experiment. FIG. 10 shows the results of the third experiment.

The conditions of the first experiment are as follows.
・ Experiment date: August 6, 2007 ・ Experiment location: Tokyo Metropolitan Industrial Technology Center ・ Experimental condition 1: Three-phase three-wire system (Δ connection), AC200 (V), 50 (Hz)
Experimental condition 2: R phase_ground capacitance; 0.47 (μF), 31.1 (mA)
: T phase_ground capacitance; 0 (μF), 0 (mA)

  In the first experiment, an experiment was performed assuming that ground resistance occurs in the R phase and the T phase in an unbalanced state where ground capacitance occurs in the R phase and ground capacitance does not occur in the T phase. went.

“I ₀ ” (leakage current), “I ₀ r” (resistance component leakage current due to ground insulation resistance), and “θ” (phase difference) in FIG. 8 are values detected by the detection device 1. Further, “Freak” in FIG. 8 is a current value measured by an ammeter. It can be seen that “I ₀ ” detected by the detection device 1 is substantially the same as the value of “Freak”.

Here, Experiment No. 1, I ₀ r is “16.3 (mA)”. However, experiment no. In 1, since no ground insulation resistance is generated in the R phase and the T phase, I ₀ r should actually be “0 (mA)”.

In the first experiment, since the capacitance to ground of the R-phase is greater than the earth capacitance of the T-phase, includes a virtual I _{0 r} to I 0 _r, it has become excessively large value. In the first experiment, “16.3 (mA)” is the virtual I ₀ r.

That is, Experiment No. 1 to Experiment No. The _{I 0} r up 13 includes the virtual _{I 0} r. Correction unit 16 subtracts the virtual _{I 0} r from _{I 0} r, can be calculated actual _{I 0} r.

The conditions for the second experiment are as follows.
・ Experiment date: August 6, 2007 ・ Experiment location: Tokyo Metropolitan Industrial Technology Center ・ Experimental condition 1: Three-phase three-wire system (Δ connection), AC200 (V), 50 (Hz)
Experimental condition 2: R phase_ground capacitance; 1.0 (μF), 65.6 (mA)
: T phase_ground capacitance; 0 (μF), 0 (mA)

  In the second experiment, as in the first experiment, a ground capacitance is generated in the R phase, and a ground insulation resistance is generated in the R phase and the T phase in an unbalanced state where no ground capacitance is generated in the T phase. An experiment was conducted assuming that this was the case.

Here, Experiment No. 14, I ₀ r is “35.4 (mA)”. However, experiment no. 14, since ground insulation resistance is not generated in the R phase and the T phase, I ₀ r should actually be “0 (mA)”.

In the second experiment, since the capacitance to ground of the R-phase is greater than the earth capacitance of the T-phase, includes a virtual I _{0 r} to I 0 _r, it has become excessively large value. In the second experiment, “35.4 (mA)” is the virtual I ₀ r.

That is, Experiment No. No. 14 to Experiment No. I ₀ r up to 26 includes virtual I ₀ r. Correction unit 16 subtracts the virtual _{I 0} r from _{I 0} r, can be calculated actual _{I 0} r.

The conditions of the third experiment are as follows.
・ Experiment date: August 6, 2007 ・ Experiment location: Tokyo Metropolitan Industrial Technology Center ・ Experimental condition 1: Three-phase three-wire system (Δ connection), AC200 (V), 50 (Hz)
Experimental condition 2: R phase_ground capacitance; 1.0 (μF), 65.6 (mA)
: T phase_ground capacitance; 0.47 (μF), 31.1 (mA)

  In the third experiment, an experiment was performed assuming that ground insulation resistance was generated in the R phase and the T phase in an unbalanced state where different ground capacitances were generated in the R phase and the T phase. In the third experiment, it is assumed that the R-phase ground capacitance is larger than the T-phase ground capacitance.

Here, Experiment No. 1, I ₀ r is “17.9 (mA)”. However, experiment no. In 1, since no ground insulation resistance is generated in the R phase and the T phase, I ₀ r should actually be “0 (mA)”.

In a third experiment, since the capacitance to ground of the R-phase is greater than the earth capacitance of the T-phase, includes a virtual I _{0 r} to I 0 _r, it has become excessively large value. In the third experiment, “17.9 (mA)” is the virtual I ₀ r.

That is, Experiment No. 1 to Experiment No. The _{I 0} r up 13 includes the virtual _{I 0} r. Correction unit 16 subtracts the virtual _{I 0} r from _{I 0} r, can be calculated actual _{I 0} r.

<When the T-phase ground capacitance (I ₀ c (t)) is larger than the R-phase ground capacitance (I ₀ c (r))>
_Then, if I 0 than _{c (r) I 0 c (} t) is _large, I 0 c (t) and _I 0 vector synthesis of _{c (r) I 0 c (} rt) is 180 degrees It becomes a larger angle direction. In this case, the calculated I ₀ r is smaller than the resistance component leakage current caused by the actual ground insulation resistance by subtracting the virtual I ₀ r from the resistance component leakage current caused by the actual ground insulation resistance. Value.

  Here, a case where a capacitance and a ground fault occur only in the T phase will be considered with reference to FIG.

Note that I ₀ c when the electrostatic capacities generated in the R phase and the T phase are equal and the electrostatic capacities are balanced is I ₀ c (3). I ₀ c (3) occurs at an angle of π (180 degrees) as shown in FIG.

Further, let I ₀ c be I ₀ c (4) when capacitance occurs only in the T phase and the capacitance is unbalanced. I ₀ c (4) occurs at an angle of 7π / 6 (210 degrees) as shown in FIG.

Further, since a ground fault occurs only in the T phase, I ₀ r is set to I ₀ r (3). I ₀ r (3) occurs at an angle of 2π / 3 (120 degrees) as shown in FIG.

In the case where the capacitance is _balanced, I 0 c (3) and _I 0 r (3) and the _{I 0} synthesized _I 0 that (T3) of. In the state where the capacitance is balanced, the virtual I ₀ r is not included in the I ₀ r calculated by the equation (1).

On the other hand, when the electrostatic capacitance is _unbalanced, I 0 c (4) and _I 0 r (3) and the _{I 0} synthesized _I 0 that (T4) a. In the state of the capacitance unbalance, the I _{0 r} calculated by equation (1) includes a virtual I _{0 r.}

Therefore, even if the magnitude of I ₀ c is the same as the magnitude of I ₀ , if the capacitance is in an unbalanced state, I ₀ r calculated by equation (1) is a value obtained by subtracting virtual I ₀ r It is over the value that actually occurs.

  The same applies to the case where capacitance occurs only in the R phase and a ground fault occurs only in the R phase.

  Here, FIGS. 12 to 14 show experimental results when the ground capacitance is in an unbalanced state. FIG. 12 shows the results of the fourth experiment. FIG. 13 shows the results of the fifth experiment. FIG. 14 shows the results of the sixth experiment.

The conditions of the fourth experiment are as follows.
・ Experiment date: August 6, 2007 ・ Experiment location: Tokyo Metropolitan Industrial Technology Center ・ Experimental condition 1: Three-phase three-wire system (Δ connection), AC200 (V), 50 (Hz)
Experimental condition 2: R phase_ground capacitance; 0 (μF), 0 (mA)
: T phase_ground capacitance; 0.47 (μF), 31.1 (mA)

  In the fourth experiment, an experiment was performed assuming that ground resistance occurs in the R phase and the T phase in an unbalanced state where ground capacitance occurs in the T phase and ground capacitance does not occur in the R phase. went.

Here, Experiment No. 1, I ₀ r is “18.3 (mA)”. However, experiment no. In 1, since no ground insulation resistance is generated in the R phase and the T phase, I ₀ r should actually be “0 (mA)”.

In the fourth experiment, since the T-phase ground capacitance is larger than the R-phase ground capacitance, I ₀ r is subtracted from the actual value by the virtual I ₀ r and becomes an undervalue. . In the fourth experiment, “18.3 (mA)” is the virtual I ₀ r.

That is, Experiment No. 1 to Experiment No. I ₀ r up to 13 is subtracted by the virtual I ₀ r. Correcting unit 16, by adding the virtual _{I 0} r to _{I 0} r, it can be calculated actual _{I 0} r.

The conditions of the fifth experiment are as follows.
・ Experiment date: August 6, 2007 ・ Experiment location: Tokyo Metropolitan Industrial Technology Center ・ Experimental condition 1: Three-phase three-wire system (Δ connection), AC200 (V), 50 (Hz)
Experimental condition 2: R phase_ground capacitance; 0 (μF), 0 (mA)
: T phase_ground capacitance; 1.0 (μF), 65.6 (mA)

  In the fifth experiment, as in the fourth experiment, a ground capacitance is generated in the T phase, and a ground insulation resistance is generated in the R phase and the T phase in an unbalanced state where no ground capacitance is generated in the R phase. An experiment was conducted assuming that this was the case.

Here, Experiment No. 14, I ₀ r is “38.1 (mA)”. However, experiment no. 14, since ground insulation resistance is not generated in the R phase and the T phase, I ₀ r should actually be “0 (mA)”.

In the fifth experiment, since the T-phase ground capacitance is larger than the R-phase ground capacitance, I ₀ r is subtracted from the actual value by the virtual I ₀ r and becomes an undervalue. . In the fifth experiment, “38.1 (mA)” is the virtual I ₀ r.

That is, Experiment No. No. 14 to Experiment No. I ₀ r up to 26 is subtracted by the virtual I ₀ r. Correcting unit 16, by adding the virtual _{I 0} r to _{I 0} r, it can be calculated actual _{I 0} r.

The conditions of the sixth experiment are as follows.
・ Experiment date: August 6, 2007 ・ Experiment location: Tokyo Metropolitan Industrial Technology Center ・ Experimental condition 1: Three-phase three-wire system (Δ connection), AC200 (V), 50 (Hz)
Experimental condition 2: R phase_ground capacitance; 0.47 (μF), 31.1 (mA)
: T phase_ground capacitance; 1.0 (μF), 65.6 (mA)

  In the sixth experiment, an experiment was performed assuming that ground insulation resistance was generated in the R phase and the T phase in an unbalanced state in which different ground capacitances were generated in the R phase and the T phase. In the sixth experiment, it is assumed that the T-phase ground capacitance is larger than the R-phase ground capacitance.

Here, Experiment No. 1, I ₀ r is “21.6 (mA)”. However, experiment no. In 1, since no ground insulation resistance is generated in the R phase and the T phase, I ₀ r should actually be “0 (mA)”.

In the sixth experiment, since the T-phase ground capacitance is larger than the R-phase ground capacitance, I ₀ r is subtracted from the actual value by the virtual I ₀ r and becomes an undervalue. . In the sixth experiment, “21.6 (mA)” is the virtual I ₀ r.

That is, Experiment No. 1 to Experiment No. I ₀ r up to 13 is subtracted by the virtual I ₀ r. Correcting unit 16, by adding the virtual _{I 0} r to _{I 0} r, it can be calculated actual _{I 0} r.

<For arithmetic expression method of derivation of calculating the I 0 _r>
Next, a method for deriving equation (1) for calculating I ₀ r in the vector theory I ₀ r method will be described. With reference to the interphase voltage V between the R phase and the T phase, I ₀ r can be obtained from the phase difference θ between the leakage current I ₀ flowing through the ground line and the interphase voltage V (T → R).

From the vector diagram shown in FIG. 4, when R → T and T → S are inverted and the vector diagram is arranged based on T → R, the vector diagram shown in FIG. 15 is obtained. Using T → R as a reference, S → R advances by π / 3, and S → T advances by 2π / 3. Also, I ₀ c (rt), which is a vector composition of I ₀ c (r) and I ₀ c (t), which is π / 2 ahead of S → R and S → T, is π. Therefore, the leakage current I ₀ is generated in the region from π / 3 to 2π / 3.

The phase difference detection unit 13 calculates the phase difference θ based on the waveform of the leakage current I ₀ sent from the leakage current detection unit 11 and the waveform of V (T → R) sent from the voltage detection unit 12. To detect.

A procedure for matching the phases of I ₀ r (r) and I ₀ r (t) will be described. across the π / 2, π / 3 of a phase difference _I 0 r and (r) by matching the phase angle of the _I 0 r (t), obtains the _{I 0} r.

That is, as shown in FIG. 16, since the phase difference θ is “π / 2 <θ” and “sin θ = sin (π−θ)”, I ₀ c (rt) is changed from T → R. The S → T of 2π / 3 becomes “Sin2π / 3 = Sin (π-2π / 3) = Sinπ / 3” and overlaps with S → R of π / 3. Further, a perpendicular line is drawn from the leakage current I ₀ to T → R, and equation (3) can be obtained from a trigonometric function.
Cos (π / 6) = I ₀ × sin θ / I ₀ r (3)
By developing the expression (3), the expression (1) can be derived.

Further, in the vector theory I ₀ r method, since I ₀ r is calculated using V (T → R) as a reference voltage, the S-phase leakage current can also be detected and affected by I ₀ c (s). Therefore, more stable measurement accuracy can be realized.

<About voltage measurement>
When a high voltage (for example, 6600V) is applied to the electric line to be measured, the high voltage is changed to a predetermined voltage (for example, 200V or 110V) by using a grounded instrument transformer (EVT). A configuration may be adopted in which the voltage is stepped down and the voltage after the step-down is input to the voltage detection unit 12. Furthermore, a phase shift may occur when the voltage is stepped down by a grounded instrument transformer (EVT). The phase difference detection unit 13 has a function of correcting a phase shift caused by a grounded instrument transformer (EVT).

<Method>
Next, the detection information notification procedure by the detection apparatus 1 will be described with reference to the flowchart shown in FIG.

In step S1, the leakage current detector 11 detects the leakage current I ₀ flowing in the measured electric line.

  In step S2, the voltage detection unit 12 detects a voltage applied between any two phases of the measured electric line.

  In step S <b> 3, the phase difference detection unit 13 detects the phase difference θ based on the leakage current detected by the leakage current detection unit 11 and the voltage detected by the voltage detection unit 12.

In step S4, the specifying unit 14 arranges the leakage current detected by the leakage current detection unit 11 at a position on the coordinates defined by the phase difference detected by the phase difference detection unit 13, thereby vectorizing the leakage current. The change in the vector of at least two leakage currents is analyzed, and the state of the measured electrical line is specified based on the analysis result. Specifying the state of the line to be measured is to identify the phase in which the ground fault occurs, or the ground capacitance flowing in each of the two ungrounded phases is in an equilibrium state or in an unbalanced state. It is to identify. In addition, the state of the electric line to be measured is specified as I I calculated by the resistance component leakage current calculation unit 15 when it is specified that the ground capacitances flowing in the two ungrounded phases are in an unbalanced state. _For example, it is specified whether ₀ r is an excessive value or an excessive value.

Therefore, the detection apparatus 1 can analyze the leakage current I _0, to identify whether the measured electric line is in any state from the results of this analysis.

<Program>
In the present embodiment, the configuration and operation of the detection apparatus 1 that mainly analyzes the leakage current I ₀ and identifies the state of the measured electric wire from the analysis result have been described. However, the present invention is not limited to this, and each component may be provided, and may be configured as a method and a program for analyzing the leakage current I ₀ and identifying the state of the measured electric wire from the analysis result. Good.

  Further, it is realized by recording a program for realizing each function constituting the detection apparatus 1 on a computer-readable recording medium, causing the computer system to read and execute the program recorded on the recording medium. May be.

  Specifically, the program includes a leakage current detection step for detecting a leakage current flowing in the measured electric line and a voltage detection for detecting a voltage applied between any two phases of the measured electric line. A phase difference detection step for detecting a phase difference based on the step, a leakage current detected by the leakage current detection step and a voltage detected by the voltage detection step, and a phase difference detected by the phase difference detection step. By placing the leakage current detected by the leakage current detection process at a position on the coordinates to be indicated by a vector, the leakage current is represented by a vector, and the change in the vector of at least two leakage currents is analyzed. It is a detection program for implement | achieving the specific process which specifies the state of a to-be-measured electric wire path by computer.

  Furthermore, the “computer system” here includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a hard disk built in the computer system.

  Furthermore, “computer-readable recording medium” means a program that dynamically holds a program in a short period of time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line In this case, a volatile memory inside a computer system that serves as a server or a client may also include a program that holds a program for a certain period of time. Further, the program may be for realizing a part of the above-described functions, and may be capable of realizing the above-described functions in combination with a program already recorded in the computer system. .

DESCRIPTION OF SYMBOLS 1 Detection apparatus, 10 Detection part, 11 Leakage current detection part, 12 Voltage detection part, 13 Phase difference detection part, 14 Identification part, 15 Resistance component leakage current calculation part, 16 Correction part, 20 Determination part, 30 Notification part, 100 Clamp part

Claims (7)

In a detection device for detecting the state of a three-phase three-wire type electric wire to be measured in which three phases (R phase, S phase, T phase) are Δ-connected, one of the phases is grounded, and a ground wire is drawn out.
A leakage current detector for detecting a leakage current flowing in the measured electric line;
A voltage detection unit for detecting a voltage applied between any two phases of the measured electrical line;
A phase difference detection unit for detecting a phase difference based on the leakage current detected by the leakage current detection unit and the voltage detected by the voltage detection unit;
By arranging the leakage current detected by the leakage current detection unit at a position on the coordinates defined by the phase difference detected by the phase difference detection unit, the leakage current is indicated by a vector, and at least two leakage currents A detection apparatus comprising a specifying unit that analyzes a change in a vector and specifies a state of the measured electric wire path based on an analysis result.   The specifying unit includes a first vector obtained by arranging the first leakage current detected by the leakage current detection unit at a position on coordinates determined by the first phase difference detected by the phase difference detection unit; The difference from the second vector obtained by arranging the second leakage current detected by the leakage current detection unit at a position on the coordinates defined by the second phase difference detected by the phase difference detection unit. The detection device according to claim 1, wherein a third vector is calculated, and a ground fault phase is specified based on an angle formed by the third vector.   The specifying unit includes a first vector obtained by arranging the first leakage current detected by the leakage current detection unit at a position on coordinates determined by the first phase difference detected by the phase difference detection unit; The difference from the second vector obtained by arranging the second leakage current detected by the leakage current detection unit at a position on the coordinates defined by the second phase difference detected by the phase difference detection unit. A third vector is calculated, and based on an angle formed by the third vector, it is specified whether a ground capacitance flowing in each of two phases not grounded is in an equilibrium state or an unbalanced state. The detection apparatus according to 1 or 2. Based on the phase insulation detected by the phase difference detection unit and the leakage current detected by the leakage current detection unit, due to the ground insulation resistance included in the leakage current flowing through the measured electric line A resistance component leakage current calculation unit for calculating the resistance component leakage current to be
When the specific unit specifies that the ground capacitances flowing in the two phases that are not grounded are in an unbalanced state, the resistance component leakage current calculated by the resistance component leakage current calculation unit is an excessive value. The detection device according to claim 3, wherein the detection device specifies whether the value is an excessively small value.   The specific unit determines that the ground capacitances flowing through the two ungrounded phases are in an unbalanced state, and the resistance component leakage current calculated by the resistance component leakage current calculation unit is an excessive value. In this case, the excessive value is calculated, the excessive value calculated from the resistance component leakage current calculated by the resistance component leakage current calculation unit is subtracted, and the ground capacitances flowing in the two phases not grounded respectively. Is in an unbalanced state, and it is determined that the resistance component leakage current calculated by the resistance component leakage current calculation unit is an excessively small value, this excessive value is calculated and the resistance component leakage current calculation unit calculates The detection device according to claim 4, further comprising: a correction unit that adds the calculated excessive value to the calculated resistance component leakage current. In a detection method for detecting the state of a three-phase three-wire type electric line to be measured in which three phases (R phase, S phase, T phase) are Δ-connected, one of the phases is grounded, and a ground wire is drawn out.
A leakage current detection step of detecting a leakage current flowing in the measured electric line;
A voltage detection step of detecting a voltage applied between any two phases of the measured electrical line;
A phase difference detection step of detecting a phase difference based on the leakage current detected by the leakage current detection step and the voltage detected by the voltage detection step;
By arranging the leakage current detected by the leakage current detection step at a position on the coordinates defined by the phase difference detected by the phase difference detection step, the leakage current is indicated by a vector, and at least two leakage currents A detection method comprising a specifying step of analyzing a change in vector and specifying a state of the measured electric wire path based on an analysis result. In a detection program for detecting the state of a three-phase three-wire system to be measured in which three phases (R phase, S phase, T phase) are Δ-connected, one of the phases is grounded, and a ground wire is drawn out.
A leakage current detection step of detecting a leakage current flowing in the measured electric line;
A voltage detection step of detecting a voltage applied between any two phases of the measured electrical line;
A phase difference detection step of detecting a phase difference based on the leakage current detected by the leakage current detection step and the voltage detected by the voltage detection step;
By arranging the leakage current detected by the leakage current detection step at a position on the coordinates defined by the phase difference detected by the phase difference detection step, the leakage current is indicated by a vector, and at least two leakage currents A detection program for realizing, by a computer, a specific step of analyzing a vector change and specifying a state of the measured electric wire path based on an analysis result.

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