Accident point detecting apparatus

Abstract

To provide a fault point detection device capable of accurately determining the presence or absence of a fault point even when pulse electricity to be applied is changed.SOLUTION: A fault detection device includes a detection unit 2 for detecting installed electricity generated in an installed wire to which pulse electricity is applied by a power supply device, and a determination unit 3 for determining the presence or absence of a fault point by using a detection value of the installed electricity. The determination unit 3 performs a first determination step of determining whether or not a result of comparison between a detection value first detected by the detection unit 2 with respect to application of pulse electricity and a first reference value for determining presence or absence of application of electricity satisfies a predetermined first condition, and a post-determination step of determining, when the first condition is satisfied, whether or not a result of comparison between a post-detection value detected at a time point when a predetermined time has elapsed from a detection time point of the detection value and a post-reference value different from the first reference value satisfies a predetermined post-condition. A fault determination step of determining that there is a fault point, wherein the post-reference value is set to two or more different values corresponding to a plurality of types of pulse electricity.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a fault point detection device used in detecting ground faults and short-circuits in overhead lines. [Background technology]

[0002] Conventionally, as disclosed in Patent Document 1, for example, a fault point detection device is known that includes a high-voltage pulse generator that generates a pulsed high voltage from the DC voltage of a DC power source and transmits it to a high-voltage distribution line, a detector that detects a ground fault current caused by the high voltage transmitted by the high-voltage pulse generator, and a signal from the detector that uses the applied voltage after a preset time has elapsed since pulse injection and compares it with a preset judgment value to determine whether or not a fault point has occurred.

[0003] After the detector detects the earth fault current, the fault point detection device uses the signal from the detector to capture the applied voltage a predetermined time after the pulse injection and compares it with a predetermined judgment value, thereby being able to determine whether or not there is a fault point. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-317349 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned conventional fault point detection device is configured to capture the applied voltage after a fixed time has elapsed and make a judgment based on a fixed judgment value, so it may not be possible to properly judge whether or not there is a fault point when the pulse-like high voltage changes.

[0006] In view of the above circumstances, an object of the present invention is to provide a fault point detection device that can accurately determine the presence or absence of a fault point even if the applied pulse electricity changes. [Means for solving the problem]

[0007] The fault point detection device of the present invention comprises: a detection unit configured to be able to generate a plurality of types of pulsed electricity, electrically connected to the overhead electric wire, and capable of detecting overhead electricity generated in the overhead electric wire when the pulsed electricity is applied by a power application unit that applies one type of pulsed electricity selected from the plurality of types of pulsed electricity to the overhead electric wire; a determination unit that determines whether or not there is a fault point in the overhead electric wire based on the detection value of the overhead electric wire detected by the detection unit, The determination unit a first determination step of comparing the detection value initially detected by the detection unit in response to the application of the pulsed electricity to the overhead electric wire with a first reference value that serves as a reference value for determining whether the pulsed electricity has been applied to the overhead electric wire, and determining whether the comparison result between the detection value and the first reference value satisfies a predetermined first condition; a post-determination step of comparing a post-detection value detected when a predetermined time has elapsed since the detection unit detected the detection value with a post-reference value set as a reference different from the first reference value, when it is determined in the first determination step that the first condition is satisfied, and determining whether or not a comparison result between the post-detection value and the post-reference value satisfies a predetermined post-condition; an accident determination step of determining that there is an accident point when it is determined in the post-determination step that the post-condition is satisfied, The post-reference value is set to two or more different values ​​corresponding to the plurality of types of pulse electricity that the voltage applying unit can generate.

[0008] According to the fault point detection device having the above configuration, two or more different post-reference values ​​are set corresponding to the multiple types of pulse electricity that can be generated by the power supply unit, so that even if the type of pulse electricity to be supplied changes, the post-judgment step can be executed using the post-reference value corresponding to that pulse electricity.

[0009] In the fault point detection device of the present invention, The installation electricity is electricity that changes over time, rising to a peak value and then converging from the peak value, The first determination step is performed during the start-up of the installation electricity, The post-determination step is performed during the convergence of the installation electricity. This may be done.

[0010] In this way, the detected electrical installation can be accurately determined by judging the rise and convergence, and since there are multiple post-reference values ​​in the post-judgment step at convergence, even if the type of pulse electricity changes and the convergence time of the electrical installation changes, the presence or absence of an accident can be accurately determined by judging using the post-reference value corresponding to the pulse electricity being used.

[0011] In the fault point detection device of the present invention, the voltage application unit includes a capacitance unit capable of charging and discharging electric charges, the voltage application unit is configured to generate the pulsed electricity by discharging from the capacitance unit, The overhead electricity includes at least one of a charging component that flows through the earth capacitance of the overhead electric wire by applying a voltage to the overhead electric wire by the voltage applying unit and a ground fault component that causes a ground fault through the fault point, After determining that the first condition is satisfied in the first determination step, a waiting time from when the detection unit detects the detection value until the detection of the subsequent detection value is performed is set to a time equal to or longer than the time until the charge component substantially disappears when the charge component is contained in the installation electricity. This may be done.

[0012] In this way, the detection unit detects the post-detection value after a time equal to or longer than the time it takes for the charge component to essentially disappear when the installed electricity contains a charge component, so the judgment unit can make a judgment in the post-judgment step without being influenced by the charge component.

[0013] The fault point detection device of the present invention comprises: The two or more subsequent reference values ​​are set to a value equivalent to the first reference value or a value closer to the peak value than the first reference value. This may be done.

[0014] In this way, the post-reference value can be set in a region where differences in the characteristics of the installed electricity due to the type of pulse electricity appear.

[0015] In the fault point detection device of the present invention, After determining in the first determination step that the first condition is satisfied, two or more different waiting times are set from the time when the detection unit detects the detection value until the detection of the subsequent detection value is performed, corresponding to the plurality of types of pulse electricity that the power supply unit can generate. This may be done.

[0016] In this way, even if the type of pulse electricity to be applied changes, the post-detection value can be detected during the waiting time corresponding to the pulse electricity, and the post-determination step can be executed.

[0017] In the fault point detection device of the present invention, The voltage applying unit is configured to apply a pulse voltage as the pulse electricity to the overhead electric wire, The detection unit is configured to detect a time change in an installation current as the installation electricity flowing by applying a pulse voltage to the installation wire. This may be done.

[0018] Two or more post-reference values ​​can be set in accordance with the characteristics of the time change of the installation current, which changes as the type of pulse voltage changes. [Effects of the Invention]

[0019] As described above, the fault point detection device of the present invention can provide the excellent effect of being able to accurately determine the presence or absence of a fault point even if the applied pulse electricity changes. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic explanatory diagram of a fault point detection device according to one embodiment of the present invention. [Figure 2] In FIG. 2, (a) is a perspective view of the fault point detection device according to the embodiment, and (b) is a side view of the fault point detection device according to the embodiment. [Figure 3] FIG. 3 is a block diagram of the configuration of the fault point detection device according to the embodiment. [Figure 4] FIG. 4 is a diagram for explaining the transition of the detection value detected by the fault point detection device of the same embodiment, and shows the transition of the detection value when a pulse voltage is applied to an overhead electric wire with no fault point. [Figure 5] Figure 5 is a diagram for explaining the change in the detection value detected by the fault point detection device of the same embodiment, and shows the change in the detection value when a pulse voltage of 5 kV is applied to an overhead electric wire where an fault point is located. [Figure 6] Figure 6 is a diagram for explaining the change in the detection value detected by the fault point detection device of the same embodiment, and shows the change in the detection value when a pulse voltage of 10 kV is applied to an overhead electric wire where an fault point is located. [Figure 7] FIG. 7 is an explanatory diagram of two operation modes that can be used in the fault point detection device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, a fault point detection device according to one embodiment of the present invention will be described with reference to the accompanying drawings.

[0022] As shown in FIG. 1, the fault point detection device 1 according to this embodiment is used together with a voltage application device D that applies pulse electricity to an overhead electric wire.

[0023] The power supply device D is configured to be capable of generating multiple types of pulsed electricity, and includes a power supply unit D1 electrically connected to an overhead electric wire and applying one type of pulsed electricity selected from the multiple types of pulsed electricity to the overhead electric wire, and a power receiving unit D2 electrically connected to the ground and applying the one type of pulsed electricity to the overhead electric wire, thereby receiving earth fault electricity generated through an accident point on the overhead electric wire.

[0024] The voltage application unit D1 is configured to generate a DC pulse and apply it to the overhead electric wire. The voltage application unit D1 of this embodiment has a capacitance unit that can charge and discharge an electric charge, and is configured to generate pulse electricity (pulse voltage) by discharging the electric charge stored in the capacitance unit.

[0025] When a pulse voltage is applied to an overhead electric wire, overhead electricity (overhead current) flows through the overhead electric wire, and includes at least one of a charging component that flows through the overhead electric wire's capacitance to the ground and a ground fault component that occurs through a fault point. More specifically, if there is no fault point on the overhead electric wire, a charging current is generated in the overhead electric wire as overhead electricity (overhead current), and if there is a fault point on the overhead electric wire (more specifically, if there is a fault point on the overhead electric wire with a resistance value), a charging current and a ground fault current are generated in the overhead electric wire as overhead current.

[0026] When the installation current is only a charging current, as shown in Figure 4, the current value of the installation current I1 rises to a peak value (E1), and after reaching the peak value, gradually decays and converges (E2) over time.

[0027] When the installation current includes charging current and earth fault current, as shown in Figure 5, the current value of the installation current I2 rises to a peak value (E3), and then gradually decays and converges after reaching the peak value (E4). However, the time it takes to completely converge after reaching the peak value is longer than when the installation current includes only charging current.

[0028] Furthermore, when the installation current includes a charging current and a ground fault current, as shown in Figure 6, the higher the voltage value of the pulse voltage applied to the installation conductor, the higher the peak value of the installation current I3 at the rise (E5) of the current flowing through the installation conductor, and the smaller the attenuation rate of the current when it converges (E6).

[0029] As shown in Figure 3, the fault point detection device 1 includes a detection unit 2 that can detect the installation current generated in the overhead electric wire when a pulse voltage is applied by a voltage application device D, a discrimination unit 3 that determines whether or not there is an installation point in the overhead electric wire based on the detection value of the installation current detected by the detection unit 2, a setting switching unit 4 that switches the setting of the standard used by the discrimination unit 3 to determine whether or not there is an installation point in the overhead electric wire, and an alarm unit 5 that notifies the user when the discrimination unit 3 determines that there is an installation point in the overhead electric wire based on the detection value.

[0030] The fault point detection device 1 also has a housing 6 and a clamp unit 7 attached to the housing 6 and capable of clamping an overhead electric wire, and the clamp unit 7 has a pair of arm units 70 that can be opened and closed relative to each other (see Figures 2(a) and 2(b)).

[0031] The detection unit 2 has a current detection unit 20 configured to generate a current in response to changes in the magnetic field around the overhead power line, a conversion unit 21 that converts the current generated by the current detection unit 20 into a voltage and outputs it, a filter unit 22 that removes noise from the voltage output from the conversion unit 21, a reference setting unit 23 that sets a conversion reference value for A / D conversion (analog-to-digital conversion) of the voltage output from the conversion unit 21, and an output unit 24 that is configured to perform A / D conversion on the voltage value of the voltage from which noise has been removed by the filter unit 22 using the conversion reference value set by the reference setting unit 23, and output the obtained voltage value.

[0032] The current detection unit 20 is configured by a so-called AC current transformer. In addition, the current detection unit 20 of this embodiment is built into a pair of arm units 70 (see FIGS. 2(a) and 2(b)). Therefore, when the magnetic field around the overhead electric wire changes due to an overhead current (charging current, or charging current and ground fault current) flowing through the overhead electric wire, the current detection unit 20 is configured to generate a current in response to the change in the magnetic field.

[0033] The conversion unit 21 is configured to convert the current generated by the current detection unit 20 into a voltage, and amplify and output the converted voltage.

[0034] The voltage from which noise has been removed by filter unit 22 and the conversion reference value set by reference setting unit 23 are each sent to output unit 24. Output unit 24 is configured to derive a voltage value based on the voltage received through filter unit 22 and the conversion reference value set by reference setting unit 23, convert the voltage value into a current value, and output the current value to discrimination unit 3. Furthermore, conversion unit 21 is configured to derive a voltage value based on the absolute value of the difference between the voltage value of the amplified voltage and the conversion reference value.

[0035] The discrimination unit 3 is configured to execute a first judgment step in which the detection value first detected by the detection unit 2 in response to the application of pulsed electricity is compared as an initial detection value with a first reference value that serves as a reference value for determining whether a pulse voltage has been applied to the installation current, and to determine whether the comparison result between the initial detection value and the first reference value satisfies a predetermined first condition; a post-judgment step in which, if it is determined in the first judgment step that the first condition is satisfied, the discrimination unit 3 compares a post-detection value detected by the detection unit 2 at a time when a predetermined time has elapsed since the detection of the initial detection value with a post-reference value that is set as a reference different from the first reference value, and to determine whether the comparison result between the post-detection value and the post-reference value satisfies a predetermined post-condition; and an accident judgment step in which, if it is determined in the post-judgment step that the post-condition is satisfied, it is determined that an accident point exists.

[0036] As described above, the output unit 24 of the detection unit 2 is configured so that the detection value of the installation current detected by the detection unit 2 is sent as a current value to the discrimination unit 3. Therefore, the early detection value and the late detection value are constituted by a current value obtained by converting the voltage value output from the output unit 24.

[0037] The early detection value is composed of the current value acquired when the discrimination unit 3 is in a state before executing the first judgment step (hereinafter referred to as the standby state), and the late detection value is composed of the current value acquired when the state in which the discrimination unit 3 waits for a predetermined time after executing the first judgment step without executing the late judgment step (hereinafter referred to as the standby state) is released and the execution of the late judgment step is started.

[0038] The first condition is set as the first detection value being greater than a first reference value. Therefore, the discrimination unit 3 is configured to compare the first detection value with the first reference value, and if the first detection value is greater than the first reference value, to enter a standby state, and if the first detection value is equal to or less than the first reference value, to return to the standby state.

[0039] The standby time for maintaining the standby state without executing the post-judgment step is set to a time equal to or longer than the time until the charging component substantially disappears when the charging component is included in the installation current.

[0040] The discrimination unit 3 is configured to acquire a post-detection value when the waiting time has elapsed, compare the post-detection value with a post-reference value, and determine whether the comparison result between the post-detection value and the post-reference value satisfies a predetermined post-condition.

[0041] The post-condition is set such that the post-detection value is equal to or greater than the post-reference value. Therefore, the discrimination unit 3 is configured to compare the post-detection value with the post-reference value and determine that there is an accident point if the post-detection value is equal to or greater than the post-reference value, and to compare the post-detection value with the post-reference value and determine that there is no accident point if the post-detection value is less than the post-reference value.

[0042] The setting switching unit 4 is configured to be able to switch the settings of the latter reference value and the waiting time out of the first reference value, the latter reference value, and the waiting time.

[0043] The setting switching unit 4 of this embodiment is configured to be able to switch the settings of the post-reference value and the standby time all at once.

[0044] More specifically, as shown in Fig. 7, the setting switching unit 4 has two operation modes M set, each of which is a combination of a post-reference setting value C1 having a value set for the post-reference value and a standby time setting value C2 having a value set for the standby time. The setting switching unit 4 is configured to be able to select either one of the two operation modes M as the operation mode M to be used.

[0045] A current value is set as the post-reference set value C1 of one operation mode M, and a time is set as the standby time set value C2. A current value is also set as the post-reference set value C1 of the other operation mode M, and a time is set as the standby time set value C2.

[0046] One of the operating modes M in this embodiment is configured to correspond to the installation current generated by applying a pulse voltage of 5 kV to the installation wire, with the post-reference setting value C1 set to 360 mA and the standby time setting value C2 set to 3 ms.

[0047] The other operating mode M of this embodiment is configured to correspond to the installation current generated by applying a pulse voltage of 10 kV to the installation wire, and the post-reference setting value C1 is set to 240 mA and the standby time setting value C2 is set to 20 ms.

[0048] The first reference value is set to the same value whether one operation mode M is selected or the other operation mode M. In this embodiment, the first reference value is set to 240 [mA].

[0049] The setting switching unit 4 is configured such that, when one operation mode M is selected, the value of the post-reference setting value C1 of that operation mode M is set to the post-reference value, and the value of the standby time setting value C2 is set to the standby time; and, when the other operation mode M is selected, the value of the post-reference setting value C1 of the other operation mode M is set to the post-reference value, and the value of the standby time setting value C2 is set to the standby time.

[0050] Therefore, two different post-reference values ​​are set to correspond to the multiple types of pulse electricity that the charging unit can generate, and the post-reference value used when one operation mode M is selected is set to a value closer to the peak value than the first reference value, and the post-reference value used when the other operation mode M is selected is set to a value equivalent to the first reference value.

[0051] Furthermore, the standby time used when one operation mode M is selected and the standby time used when the other operation mode M is selected are set to different times.

[0052] When one operating mode is selected and a pulse voltage of 5 kV is applied to an overhead power line with no fault point, the early detection value of the installation current I1 exceeds the first reference value TH1 while the late detection value of the installation current I1 falls below the late reference value TH2a, so the discrimination unit 3 executes the first judgment step but does not execute the late judgment step (see Figure 4).

[0053] When one operating mode is selected and a pulse voltage of 5 kV is applied to the overhead power line where the fault point is located, the initial detection value of the installation current I2 exceeds the first reference value TH1, and further, the final detection value of the installation current I2 becomes equal to or greater than the final reference value TH2a, so the discrimination unit 3 executes the first judgment step, the final judgment step, and the fault judgment step (see Figure 5).

[0054] When one operating mode is selected and a pulse voltage of 10 kV is applied to the overhead power line where the fault point is located, the early detection value of the installation current I3 exceeds the first reference value TH1, while the late detection value of the installation current I3 falls below the late reference value TH2a, so the discrimination unit 3 executes the first judgment step but does not execute the late judgment step (see Figure 5).

[0055] When the other operating mode is selected and a pulse voltage of 5 kV is applied to an overhead power line with no fault point, the early detection value of the installation current I1 exceeds the first reference value TH1 while the late detection value of the installation current I1 falls below the late reference value TH2b, so the discrimination unit 3 executes the first judgment step but does not execute the late judgment step (see Figure 4).

[0056] When the other operating mode is selected and a pulse voltage of 10 kV is applied to the overhead power line where the fault point is located, the initial detection value of the installation current I3 exceeds the first reference value TH1, and further, the final detection value of the installation current I3 becomes equal to or greater than the final reference value TH2b, so the discrimination unit 3 executes the first judgment step, the final judgment step, and the fault judgment step (see Figure 6).

[0057] When the other operating mode is selected and a pulse voltage of 5 kV is applied to the overhead power line where the fault point is located, the early detection value of the installation current I2 exceeds the first reference value TH1, while the late detection value of the installation current I2 falls below the late reference value TH2b, so the discrimination unit 3 executes the first judgment step but does not execute the late judgment step (see Figure 6).

[0058] In this way, both the one operating mode and the other mode are designed to prevent the false determination that there is a fault point on the overhead electric wire when there is no fault point.

[0059] In addition, the fault point detection device 1 is configured so that the environments in which it can detect fault points when one operating mode is set and the environments in which it can detect fault points when the other operating mode is set are different, so that fault points are not mistakenly detected in incompatible environments.

[0060] The notification unit 5 is configured to notify a worker that there is a fault point in the overhead electric wire by emitting light or sound, for example.

[0061] The configuration of the fault point detection device 1 according to this embodiment is as described above. Next, the operation of the fault point detection device 1 will be described.

[0062] To locate the fault point, the voltage application unit D1 of the voltage application device D is electrically connected to the overhead electric wire, and the power receiving unit D2 is grounded (see FIG. 1).

[0063] Next, the voltage applying unit selects the magnitude of the pulse voltage to be applied to the overhead electric wire, and the setting switching unit 4 selects an operation mode suited to the magnitude of the pulse voltage to be applied to the overhead electric wire by the voltage applying unit.

[0064] When a pulse voltage of 5 kV is applied to an overhead electric wire, the fault point detection device 1 selects one of the operating modes, whereby the post-reference value is set to the post-reference setting value of one of the operating modes, and the standby time is set to the standby time value of one of the operating modes.

[0065] If there is no fault point on the overhead electric wire, when a pulse voltage of 5 kV is applied to the overhead electric wire, the discrimination unit 3 executes the first judgment step when the current value flowing through the overhead electric wire rises, but when the post-judgment step is executed after the waiting time has elapsed, the detected value of the overhead electric wire falls below the post-reference value TH2a (see Figure 4), so no judgment is made that there is a fault point.

[0066] If there is an accident point on the overhead power line, when a pulse voltage of 5 kV is applied to the overhead power line, the discrimination unit 3 executes a first judgment step when the current value flowing through the overhead power line rises, and if the detected value of the overhead current is equal to or greater than the post-reference value TH2b when the post-judgment step is executed after the waiting time has elapsed (see Figure 5), the accident judgment step is executed and it is determined that there is an accident point.

[0067] When one of the operating modes is selected and a pulse voltage of 10 kV is applied to the overhead power line, the detected value of the overhead power line current after the waiting time has elapsed falls below the post-reference value TH2a (see Figure 5), regardless of whether or not there is a fault point, and therefore no determination is made that there is a fault point.

[0068] When a pulse voltage of 10 kV is applied to an overhead electric wire, the fault point detection device 1 selects one of the operating modes, whereby the post-reference value is set to the post-reference setting value of one of the operating modes, and the standby time is set to the standby time value of one of the operating modes.

[0069] If there is no fault point on the overhead electric wire, when a pulse voltage of 10 kV is applied to the overhead electric wire, the discrimination unit 3 executes the first judgment step when the current value flowing through the overhead electric wire rises, but when the post-judgment step is executed after the waiting time has elapsed, the detected value of the overhead electric wire falls below the post-reference value TH2b (see Figure 4), so no judgment is made that there is a fault point.

[0070] If there is an accident point on the overhead electric wire, when a pulse voltage of 10 kV is applied to the overhead electric wire, the discrimination unit 3 executes a first judgment step when the current value flowing through the overhead electric wire rises, and if the detected value of the overhead current is equal to or greater than the post-reference value TH2b when the post-judgment step is executed after the waiting time has elapsed (see Figure 6), the accident judgment step is executed and it is determined that there is an accident point.

[0071] When one of the operating modes is selected and a 5 kV pulse voltage is applied to the overhead power line, the detected value of the overhead power line current after the waiting time has elapsed falls below the post-reference value TH2b (see Figure 6), regardless of whether or not there is a fault point, and therefore no determination is made that there is a fault point.

[0072] As described above, in the fault point detection device 1 of this embodiment, two or more different post-reference values ​​are set corresponding to the multiple types of pulse electricity that the charging unit can generate, so even if the type of pulse electricity to be applied changes, the post-judgment step can be executed using the post-reference value corresponding to that pulse electricity.

[0073] Therefore, the fault point detection device 1 can achieve the excellent effect of being able to accurately determine whether or not a fault point exists even if the applied pulse electricity changes.

[0074] Furthermore, the first judgment step by the discrimination unit 3 is executed during the rise of the installation current, and the subsequent judgment step is executed during the convergence of the installation current, so that the detected installation current can be accurately discriminated by judging the rise and convergence.

[0075] In the post-judgment step at convergence, there are multiple post-reference values, so even if the type of pulse electricity changes and the convergence time of the installation current changes, the corresponding post-reference value can be used to accurately determine whether or not there is an accident.

[0076] Furthermore, in the fault point detection device 1 of this embodiment, the detection unit 2 detects the post-detection value after a time equal to or longer than the time it takes for the charge component to substantially disappear when the installation current contains a charge component has elapsed, so the judgment unit 3 can make a judgment in the post-judgment step without being influenced by the charge component.

[0077] Furthermore, since the two or more subsequent reference values ​​are set to a value equivalent to the first reference value or a value closer to the peak value than the first reference value, the subsequent reference values ​​can be set in a region where differences in the characteristics of the installation current due to the type of pulse electricity are apparent.

[0078] Furthermore, the waiting time from when the detection unit 2 detects the detection value after determining that the first condition is met in the first determination step until when it detects the post-detection value is set to two or more different times corresponding to the multiple types of pulse electricity that the charging unit can generate, so even if the type of pulse electricity to be applied changes, the post-detection value can be detected within the waiting time corresponding to that pulse electricity and the post-determination step can be executed.

[0079] Furthermore, since the voltage application unit is configured to apply a pulse voltage to the overhead electric wire as pulse electricity, and the detection unit 2 is configured to detect the time change in the installation current as the installation current that flows as a result of the pulse voltage being applied to the overhead electric wire, two or more subsequent reference values ​​can be set in accordance with the characteristics of the time change in the installation current that changes as the type of pulse voltage changes.

[0080] The fault point detection device according to the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0081] Although not specifically mentioned in the description of the setting switching unit 4 of the above embodiment, the setting switching unit 4 may be configured to allow the operation mode to be selected using a switch or the like, or may be configured to allow the operation mode to be selected using a remote control or the like.

[0082] Furthermore, the setting switching unit 4 may be manually operated by an operator, or may be configured to automatically select and switch between a plurality of operation modes to be used.

[0083] When the setting switching unit 4 is configured to automatically select and switch one of a plurality of operating modes to be used, it may be configured, for example, to select an operating mode other than the operating mode currently in use when the discrimination unit 3 determines in the post-judgment step that the post-condition is not satisfied, and to cause the discrimination unit 3 to execute the post-judgment step again.

[0084] Although the number of post-references described in the above embodiment is two, it may be, for example, three or more. Furthermore, the number of post-references does not have to match the number of pulse voltages that can be applied to the overhead electric wire by the voltage application device D.

[0085] In the above embodiment, the first reference value is set to a common value for each operation mode. However, for example, the first reference value may be configured to be set to a different value for each operation mode.

[0086] In the above embodiment of the fault point detection device 1, the rear reference value used when one operating mode M is selected is set to a value closer to the peak value than the first reference value, and the rear reference value used when the other operating mode M is selected is set to a value equal to the first reference value, but it is also possible to set either rear reference value to a value lower than the first reference value.

[0087] In the above embodiment of the fault point detection device 1, the rear reference value used when one operation mode M is selected and the rear reference value used when the other operation mode M is selected are set to different values, but the respective rear reference values ​​may also be set to the same value.

[0088] In the fault point detection device 1 of the above embodiment, the standby time used when one operation mode M is selected and the standby time used when the other operation mode M is selected are set to different times, but they may also be set to the same time. [Explanation of symbols]

[0089] 1...fault point detection device, 2...detection unit, 3...discrimination unit, 4...setting switching unit, 5...alarm unit, 6...casing, 7...clamp unit, 20...current detection unit, 21...conversion unit, 22...filter unit, 23...reference setting unit, 24...output unit, 70...arm unit, C1...post-reference setting value, C2...standby time setting value, D...power application device, D1...power application unit, D2...power receiving unit, I1, I2, I3...installation current, M...operation mode, TH1...first reference value, TH2a, TH2b...post-reference value

Claims

1. a detection unit configured to be able to generate a plurality of types of pulsed electricity, electrically connected to the overhead electric wire, and capable of detecting overhead electricity generated in the overhead electric wire when the pulsed electricity is applied to the overhead electric wire by a power application unit that applies one type of pulsed electricity selected from the plurality of types of pulsed electricity to the overhead electric wire; a determination unit that determines whether or not there is a fault point in the overhead electric wire based on the detection value of the overhead electric wire detected by the detection unit, The determination unit a first determination step of comparing the detection value detected by the detection unit in response to the application of the pulsed electricity to the overhead electric wire with a first reference value that serves as a reference value for determining whether the pulsed electricity has been applied to the overhead electric wire, and determining whether the comparison result between the detection value and the first reference value satisfies a predetermined first condition; a post-determination step of comparing a post-detection value detected when a predetermined time has elapsed since the detection unit detected the detection value with a post-reference value set as a reference different from the first reference value, when it is determined in the first determination step that the first condition is satisfied, and determining whether or not a comparison result between the post-detection value and the post-reference value satisfies a predetermined post-condition; an accident determination step of determining that there is an accident point when it is determined in the post-determination step that the post-condition is satisfied, The post-reference value is set to two or more different values ​​corresponding to the plurality of types of pulse electricity that can be generated by the voltage applying unit. Fault point detection device.

2. The installation electricity is electricity that changes over time, rising to a peak value and then converging from the peak value, The first determination step is performed during the start-up of the installation electricity, The post-determination step is performed during the convergence of the installation electricity. The fault point detection device according to claim 1 .

3. the voltage application unit includes a capacitance unit capable of charging and discharging electric charges, the voltage application unit is configured to generate the pulsed electricity by discharging from the capacitance unit, The overhead electricity includes at least one of a charging component that flows through the earth capacitance of the overhead electric wire by applying a voltage to the overhead electric wire by the voltage applying unit and a ground fault component that causes a ground fault through the fault point, After determining that the first condition is satisfied in the first determination step, a waiting time from the time when the detection unit detects the detection value until the detection of the subsequent detection value is performed is set to a time equal to or longer than the time until the charge component substantially disappears when the charge component is contained in the installation electricity. The fault point detection device according to claim 1 or 2.

4. The two or more subsequent reference values ​​are set to a value equal to the first reference value or a value closer to the peak value than the first reference value. The fault point detection device according to claim 2.

5. after determining in the first determination step that the first condition is satisfied, two or more different waiting times are set for the time from when the detection unit detects the detection value until the detection of the subsequent detection value is executed, in accordance with the plurality of types of pulse electricity that the power supply unit can generate. The fault point detection device according to claim 1 or 2.

6. The voltage applying unit is configured to apply a pulse voltage as the pulse electricity to the overhead electric wire, The detection unit is configured to detect a time change in an installation current as the installation electricity flowing by applying a pulse voltage to the installation wire. The fault point detection device according to claim 1 or 2.

Images