JP2001083203A - Method and apparatus for checking disconnection of hot- line deterioration diagnosing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and effectively check the presence or absence of a disconnection of a diagnosing lead wire or the like while simplifying a complicated work on a post before diagnosing an insulation deterioration of a high tension CV cable due to a water tree or the like in a hot-like state. SOLUTION: The presence or absence of a disconnection of a diagnosing lead wires 7, 7' is decided by constituting a closed circuit including the wires 7, 7' and an existing ground wire 9 and the like by a disconnection checking apparatus 2 connected in series with the wires 7, 7' in parallel or in series with a hot-line deterioration diagnosing device 1 as seen from a shield layer 8 of a CV cable while the wire 9 of the cable remains closed and confirming the presence or absence of a DC current flowing through the closed circuit by applying a DC voltage from the apparatus 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for diagnosing hot wire deterioration of a power cable, and more particularly to diagnosing insulation deterioration of a crosslinked polyethylene insulated power cable in a live state, which is called a CV cable. The present invention relates to a method and an apparatus for diagnosis, and more particularly, to a method and an apparatus for checking the presence / absence of disconnection of a diagnosis apparatus including a diagnostic lead wire in a live-line deterioration diagnosis.

[0002]

2. Description of the Related Art Insulating materials of power cables, particularly insulating materials of high molecular compounds, deteriorate in their insulation characteristics due to aging during use. It is known that deterioration due to water trees occurs mainly in CV cables. To prevent an accident due to insulation breakdown, a method of diagnosing the degree of insulation deterioration in a live state is disclosed in, for example, Japanese Patent Application Laid-Open No. 202074 and JP-A-59-202075. In these methods, a diagnostic device is connected between the shield layer of the power cable for performing the deterioration diagnosis and the ground via two diagnostic leads on the shield layer side and the ground side, and an insulator such as a water tree is connected. The magnitude and polarity of the DC component of the current flowing through the shielding layer of the CV cable due to the deteriorated portion are measured by a diagnostic device to detect the size and position of a water tree or the like.

[0003] However, a mechanical load such as tension is applied to the diagnostic lead wire used for the above-mentioned diagnosis during connection work or mounting work on a pole, so that the conductor is liable to be broken. Become. If a disconnection occurs in the diagnostic lead wire and the live-line degradation diagnostic device that cooperates with the diagnostic lead wire, the measurement current does not flow through the diagnostic device, and an erroneous determination is made that the power cable to be measured has not deteriorated. It will be invalid. In order to prevent this, various methods have been proposed for checking whether or not the diagnostic lead wire is disconnected.
In particular, FIG.
The diagnostic lead wire is mounted on a pillar for live line deterioration diagnosis and connected to the shielding layer of the CV cable as disclosed in the above item, and the diagnosis lead wire is disconnected immediately before the insulation deterioration diagnosis. Checking is done on the fly. In this method, the live-line degradation diagnostic device 11 is connected between the shield layer 18 of the power cable to be diagnosed and the ground via diagnostic leads 17 and 17 ′, and the diagnosis is performed from the shield layer 18 of the CV cable. The disconnection check device 12 is inserted in parallel with the diagnostic leads 11 and 17 ′ and the diagnostic device 11 to form a closed circuit together with the diagnostic leads 17 and 17 ′ and the live-line degradation diagnostic device 11. 12 DC power supplies 13
A DC voltage is applied to the diagnostic lead wire 1 by measuring a DC current flowing through a closed circuit according to the resistor 14.
The disconnection check of 7 and 17 'was performed.

[0004]

The disconnection check by this method is performed by the disconnection check device 12 in parallel with the diagnostic lead wires 17 and 17 ′ and the live-line degradation diagnostic device 11 as viewed from the shielding layer 18 of the CV cable. Therefore, it is necessary to connect the shielding layer side diagnostic lead wire 17 and the disconnection check device 12 in parallel to the shielding layer 18 of the cable to be diagnosed on the pillar, and the work on the pillar is troublesome. Was something. After the disconnection check is completed, it is necessary to disconnect the disconnection check device from the hot-line degradation diagnostic device for the hot-line degradation diagnosis, but disconnect the live-line degradation diagnostic device on the pole up to the power cable to be measured. This is very troublesome because the live-line degradation diagnostic device and the existing grounding wire are usually several tens of meters apart, and several hundred meters depending on the installation status of the power cable.

SUMMARY OF THE INVENTION It is an object of the present invention to simplify a troublesome and troublesome disconnection check operation for checking a lead wire for diagnosis of live-line deterioration, and to easily and surely check for a disconnection of a diagnostic lead wire. To provide a method and apparatus. Another object of the present invention is to provide a live-line deterioration diagnosis device incorporating a live-line deterioration diagnosis lead wire disconnection check device, which can easily and reliably check for the presence or absence of a break in a diagnosis lead wire. To provide.

[0006]

According to a first aspect of the present invention, there is provided a method for checking a disconnection of a high-voltage CV cable under a hot line. In the live line deterioration diagnosis test, a closed circuit including the diagnosis lead wire and the existing ground wire is formed by a disconnection check device connected in series with the diagnosis lead wire as viewed from the shielding layer of the CV cable, and a DC voltage is applied. It is characterized by the following. Further, in the disconnection check device of the live-line deterioration diagnosing device according to the second aspect of the present invention, in the live-line deterioration diagnostic test for diagnosing insulation deterioration of the high-voltage CV cable under the live line, the diagnosis is performed as viewed from the shielding layer of the CV cable. A closed circuit including a diagnostic lead and an existing ground line is connected in series with the lead, and a disconnection check circuit that performs a disconnection check by applying a DC voltage is included.

[0007] With this configuration, in the disconnection check method or the disconnection check device of the hot-line degradation diagnosis device according to claim 1 or 2 of the present invention, the disconnection check device of the hot-line degradation diagnosis device is viewed from the shield layer of the CV cable. The diagnostic lead is connected in series with the two diagnostic leads on the shield layer side and the ground side, so the diagnostic lead on the shield layer side is connected to the shield layer of the CV cable on the pole for live line deterioration diagnosis. The diagnostic lead and the diagnostic lead connected to the shield layer and the diagnostic lead connected to the shield layer of the CV cable for performing deterioration diagnosis in the live state only by connecting the ground diagnostic lead to the ground. Since the line and disconnection check device form a closed circuit, when a power supply included in the disconnection check device applies a DC voltage to the closed circuit, two diagnostic leads and the closed circuit are formed. Other elements are not direct current flows if disconnected, the DC current corresponding to the resistance value of the applied voltage and the circuit if there is disconnection thereof. As a result, there is no need to mount the disconnection check device on the pole, and it is not necessary to access the power cable to be diagnosed to disconnect the check device after the disconnection check is completed, and the disconnection check device can be operated with the switch at hand. It is possible to know very easily and surely whether the diagnostic lead wire is disconnected or not.

According to a third aspect of the present invention, there is provided an apparatus for diagnosing a deterioration of a high-voltage CV cable under a hot wire in a live-line deterioration diagnosis test, wherein the diagnostic lead is viewed from a shielding layer of the CV cable. A disconnection check device that includes a disconnection check circuit that performs a disconnection check circuit that performs a disconnection check by applying a DC voltage is connected, forming a closed circuit that includes a diagnostic lead wire and an existing ground wire connected in series with the wire. I do. With this configuration, in the live-line deterioration diagnostic apparatus according to the third aspect of the present invention, a diagnostic lead itself used for live-line deterioration diagnosis and a device for checking the disconnection of the circuit wiring of the existing ground line are incorporated in the diagnostic device itself. Therefore, without carrying a separate disconnection check device, only two diagnostic leads are mounted between the live wire deterioration diagnostic device and the shielding layer of the cable to be diagnosed. It is possible to check very easily and surely whether there is a disconnection between the diagnostic lead wire and the existing ground wire, or between them and the hot-line degradation diagnostic device.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method and an apparatus for checking disconnection of a live-line deterioration diagnosis apparatus according to the present invention will be described below in detail with reference to the drawings. FIG. 1 and FIG. 2 are explanatory diagrams of a partly blocked live-line degradation diagnosis and a disconnection check, showing an example of the implementation of the disconnection check by the disconnection check device of the live-line degradation diagnostic device according to the present invention. In the example of FIG. 1, the disconnection check device is connected in series with the lead wire for live line deterioration diagnosis, and in parallel with the live line deterioration diagnostic device similar to a conventional product, and is integrated into one housing. ing.
In the example of FIG. 2, the disconnection check device is connected in series with the lead wire for live-line deterioration diagnosis, and connected in series with the live-line deterioration diagnostic device similar to a conventional product, and is integrated and integrated into one housing. I have.

In FIG. 1, a disconnection check device 2 incorporated in a live-line deterioration diagnosis device 1 has a DC power supply 3, a resistor 4, a switch 5, and a DC ammeter 6 arranged in series.
It is configured to include a disconnection check circuit. In addition, the shielding layer side diagnostic lead 7 and the ground side diagnostic lead 7 ′ for the live line deterioration diagnosis are provided with the shield layer 8, the existing ground line 9, and the live line deterioration of the cable to be diagnosed for performing the deterioration diagnosis in the live state. It is connected with the disconnection check device 2 incorporated in the diagnostic device 1 to form a closed circuit, and the disconnection check device 2 is connected in series with the diagnostic leads 7 and 7 ′ and in parallel with the hot-line degradation diagnostic device 1. Have been. According to the above configuration, the disconnection check of the diagnostic lead wire 7 used for the diagnosis is performed before the insulation deterioration diagnosis of the CV cable to be diagnosed, using the disconnection check device shown in FIG. Therefore, when the switch 5 of the disconnection check device 2 is turned off while the existing ground wire 9 is turned off under the live line, the diagnostic lead wires 7 and 7 ′ connected to the shielding layer 8 of the cable to be diagnosed,
The disconnection check device 2 forms a closed circuit together with the existing ground wire 9. At this time, the DC power supply 3 included in the disconnection check device 2
By applying a DC voltage and measuring the current flowing through the closed circuit with the DC ammeter 6, the presence or absence of disconnection of the diagnostic leads 7 and 7 'can be determined. That is, if there is no disconnection, a current corresponding to the value of the resistor 4 of the disconnection check device 2 flows through the closed circuit, and if there is a disconnection, the current flowing through the closed circuit becomes zero. The disconnection check device 2 of FIG. 1 of the present invention is connected in parallel with the
Is included in the switch 5 at the time of live line deterioration diagnosis.
, The disconnection check device 2 can be very easily separated from the hot-line degradation diagnosis device 1. For this reason, the value of the resistor 4 for disconnection check can be arbitrarily selected only for the purpose of disconnection check,
The DC power supply 3 may be a 1.5V dry battery in consideration of the convenience of carrying and obtaining, and can be appropriately selected as needed.

In FIG. 2, a disconnection check device 2 of a live-line deterioration diagnosis device 1 includes a DC power supply 3, a resistor 4, a switch 5,
And a disconnection check circuit in which the DC ammeter 6 is arranged in series. The diagnostic lead wires 7 and 7 ′ for the live-line deterioration diagnosis are connected together with the shield layer 8, the existing ground line 9, and the live-line deterioration diagnosis device 1 of the cable to be diagnosed for performing the deterioration diagnosis in the live state and closed circuit. The disconnection check device 2 is connected in series with the diagnostic lead wires 7 and 7 ′ and the live-line degradation diagnostic device 1. According to the above configuration, before the insulation deterioration diagnosis of the CV cable to be diagnosed is performed, the disconnection check of the diagnostic lead wire 7 and the live-line deterioration diagnosis device 1 is performed using the disconnection check device shown in FIG. You. Therefore, when the switch 5 of the disconnection check device 2 is switched to the disconnection check device side while the existing ground wire 9 is turned off under the live line, the diagnostic lead wire 7 connected to the shielding layer 8 of the cable to be diagnosed is connected to the active wire. The line deterioration diagnosis device 1 and the disconnection check device 2 constitute a closed circuit together with the existing ground line 9. At this time, the DC power supply 3 included in the disconnection check device 2 applies a DC voltage and measures the current flowing in the closed circuit to determine whether the diagnostic lead wire 7 and the hot-line degradation diagnostic device 1 are disconnected. I do.
That is, if there is no disconnection, a current corresponding to the value of the resistor 4 of the disconnection check device 2 flows through the closed circuit, and if there is a disconnection, the current flowing through the closed circuit becomes zero. Since the disconnection check device 2 of FIG. 2 of the present invention is connected in series with the hot-line deterioration diagnostic device 1 and includes the switch 5, the switch 5 is switched to the diagnostic device side at the time of hot-line deterioration diagnosis. The disconnection check device 2 can be very easily separated from the live-line deterioration diagnosis device 1. For this reason, the value of the resistor 4 for disconnection check can be arbitrarily selected only for the purpose of disconnection check, and the DC power supply 3 may be a 1.5 V dry battery in consideration of convenience in carrying and obtaining. You can choose.

When performing the hot-line deterioration diagnosis, a disconnection check according to the present invention is performed to determine the live-line deterioration diagnosis lead wire 7.
Alternatively, after confirming that there is no abnormality in the hot-wire deterioration diagnosis lead wire and the hot-line deterioration diagnosis device 1, the switch 5 is opened in the case of FIG. 1 and the switch 5 in the case of FIG. By switching 5 to the hot-line degradation diagnostic device side, the disconnection check device 2 may be separated from the hot-line degradation diagnostic device 1, the existing ground wire 9 may be opened, and a conventional normal hot-line degradation diagnosis may be performed. The circuit elements required for the disconnection check device according to the present invention are common to the circuit elements required for the hot-line degradation diagnosis device, so that they can be diverted at the time of disconnection check and hot-line degradation diagnosis. For example, the DC power supply of the disconnection check device can be diverted from the DC power supply that is usually incorporated in the live-line deterioration diagnosis device for measuring the sheath insulation resistance. In the live-line deterioration diagnosis device shown in FIG. Since the disconnection check device and the live-line degradation diagnosis device are connected in series, in this example, the disconnection check is performed by substituting the DC ammeter 6 separately provided for the disconnection check device with the DC ammeter for degradation diagnosis. The cost of the device can be reduced.

[0013]

As described above, according to the method and the apparatus for checking the disconnection of the apparatus for diagnosing hot-line deterioration according to the present invention, the C
As seen from the V cable shield layer, it is in series with the diagnostic lead wire,
Since the disconnection check device is connected in parallel or in series with the hot-line deterioration diagnosis device, it is necessary to mount the disconnection check device on the shield layer of the cable to be diagnosed on the pole to check the disconnection of the lead wire for live-line deterioration diagnosis. There is no need to disconnect the disconnection check device on the pole up to the CV cable to be measured after the completion of the disconnection check for live-line deterioration diagnosis, simplifying the troublesome and troublesome disconnection check work.
A method and apparatus are provided that enable easy and reliable checking of diagnostic leads for disconnections. In addition, the disconnection check device of the live-line deterioration diagnostic device according to the present invention is connected in series with the diagnostic lead wire as viewed from the shielding layer of the CV cable. An apparatus for diagnosing live-line deterioration that enables easy and reliable checking of the presence or absence of disconnection of a diagnostic lead wire is provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a live-line deterioration diagnosis including an example of a disconnection check device of the present invention.

FIG. 2 is an explanatory diagram of a live-line deterioration diagnosis including another example of the disconnection check device of the present invention.

FIG. 3 is an example of a conventional disconnection check device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hot-line deterioration diagnostic device 1 'Hot-line deterioration diagnostic circuit 2 Disconnection check device 3 DC power supply 4 Resistor 5 Switch 6 DC ammeter 7 Shielding layer side diagnostic lead wire 7' Earth side diagnostic lead wire 8 Shielding layer 9 Existing ground wire

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masahiro Hotta 2771 Ooka, Numazu-shi, Shizuoka Yazaki Electric Wire Co., Ltd. F-term (reference) 2G014 AA02 AB34 AC19 2G015 AA27 BA05 BA09 CA20 DA04 2G028 AA02 AA03 BB20 BF10 DH03 LR01 MS01 MS03

Claims (3)

[Claims] In a live-line deterioration diagnosis test for diagnosing insulation deterioration of a high-voltage CV cable under a live line, a diagnostic lead is connected by a disconnection check device connected in series with a diagnostic lead as viewed from a shielding layer of the CV cable. A method for checking disconnection of a live-line deterioration diagnostic device, comprising forming a closed circuit including a wire and an existing ground wire, and applying a DC voltage. 2. A live-line deterioration diagnosis test for diagnosing insulation deterioration of a high-voltage CV cable under a live line, connecting the diagnostic lead in series with a diagnostic lead viewed from a shielding layer of the CV cable, and connecting the diagnostic lead to an existing ground. A disconnection check device for a live-line deterioration diagnosis device, comprising a disconnection check circuit that forms a closed circuit including a wire and performs a disconnection check by applying a DC voltage. 3. A live-line deterioration diagnostic test for diagnosing insulation deterioration of a high-voltage CV cable under a live line, connecting the diagnostic lead in series with a diagnostic lead viewed from a shielding layer of the CV cable, and connecting the diagnostic lead to an existing ground. A live-line deterioration diagnosis device comprising a closed-circuit check device including a closed-circuit check circuit for forming a closed circuit including a wire and performing a disconnection check by applying a DC voltage.