JP4845213B2 - Moisture absorption detection method of insulator type arrester, moisture absorption deterioration detection method of insulator type arrester, and moisture absorption detection device of insulator type arrester - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method for detecting moisture absorption of an insulator type lightning arrester, a method for detecting moisture absorption deterioration of an insulator type lightning arrester, and a moisture absorption detection device for an insulator type arrester, and for example, a method for detecting moisture absorption of an insulator type arrester using terahertz waves, The present invention relates to a detection method and a moisture absorption detection device for an insulator type arrester.

  Insulator-type lightning arresters installed in power stations and substations protect the peripheral equipment from surges when abnormal voltages occur due to lightning surges caused by lightning strikes, and switching surges caused by turning on / off switches, breakers, etc. To do.

  Insulator-type lightning arresters are composed of a plurality of zinc oxide elements composed mainly of zinc oxide, which has non-linear current-voltage characteristics that have low resistance to surge voltages and high resistance to normal ground voltages. The laminated zinc oxide element has a structure in which an insulating jacket such as a polymer having elasticity is attached to the outer peripheral surface of the zinc oxide element.

  As a method for judging the deterioration of such an insulator type lightning arrester, there is conventionally a method of measuring the leakage current of an operating insulator type arrester and estimating the presence or absence of deterioration (abnormality) from the waveform. As a method of judging deterioration by measuring leakage current, for example, in Japanese Patent Laid-Open No. 63-228082 (Patent Document 1), a resistance component of leakage current of a lightning arrester is extracted and compared with a normal value. Discloses a method for diagnosing deterioration of a zinc oxide lightning arrester that is diagnosing deterioration.

As a method for measuring moisture, for example, there is a moisture measurement of a substance using a microwave. As such a method, for example, a wood moisture measuring method disclosed in Japanese Patent Laid-Open No. 2001-124707 (Patent Document 2) is disclosed.
Japanese Unexamined Patent Publication No. 63-228082 JP 2001-124707 A

  However, in the method for diagnosing deterioration of a zinc oxide arrester disclosed in Patent Document 1 above, it is possible to confirm that some change has occurred in the zinc oxide type element of the arrester by observing the leakage current. The cause cannot be identified. The wood moisture measuring method disclosed in Patent Document 2 can measure moisture, but cannot be applied to a structure containing a metal such as an insulator type arrester.

  The present invention has been made in view of the above problems, and an object of the present invention is to detect moisture absorption of a lever type lightning arrester capable of detecting whether or not a liquid such as moisture has entered the inside of the lever type lightning arrester. An object of the present invention is to provide a method for detecting moisture absorption deterioration of an insulator type lightning arrester and a moisture absorption detecting device for an insulator type arrester.

  As a result of intensive studies by the inventor of the present application, it has been discovered that terahertz waves are used when detecting liquid such as moisture in an insulator type arrester. In other words, by utilizing terahertz waves that are relatively transmitted through the insulator tube and relatively reflected from the surface of the internal zinc oxide element and are sensitive to liquids such as moisture, the internal components of the insulator type arrester are used. It has been found that liquids such as moisture entering the water are detected.

  Therefore, the method of detecting moisture absorption of the insulator type lightning arrester according to the present invention includes an insulator including a zinc oxide element composed mainly of zinc oxide and the remainder consisting of inevitable impurities, and an insulator tube containing the zinc oxide element therein and made of an insulator. A method for detecting moisture absorption by a type arrester, which carries out the following steps. First, a radiation process for emitting terahertz waves to the outer surface of the insulator type arrester is performed. And the receiving process which receives the terahertz wave reflected from a zinc oxide element is implemented. And the detection process which detects the waveform of the terahertz wave received by the terahertz wave reception process is implemented. And the inspection process which test | inspects an internal moisture absorption state is implemented by comparing and analyzing a waveform and the waveform of a normal state.

  Further, a moisture absorption detecting device for an insulator type lightning arrester according to the present invention includes an insulator including a zinc oxide element composed mainly of zinc oxide and the balance of inevitable impurities, and an insulator tube containing the zinc oxide element therein and made of an insulator. A moisture absorption detection device for a type arrester, which includes a radiation device, a detection device, and an analysis device. The radiation device radiates terahertz waves to the outer surface of the insulator type lightning arrester. The detection device receives the terahertz wave reflected from the zinc oxide element and detects the waveform of the terahertz wave. The analysis device compares and analyzes the waveform and the waveform in the normal state.

  According to the method for detecting moisture absorption of an insulator type lightning arrester and the moisture absorption detecting device for an insulator type arrester according to the present invention, when a terahertz wave is radiated from the outside of the insulator type arrester, it is transmitted through the insulator tube and reflected on the surface of the zinc oxide element. By comparing the waveform of the reflected terahertz wave with the waveform of the terahertz wave in a normal state that does not contain liquid, it is possible to detect whether liquid has entered the insulator type arrester it can.

  In the above-described method of detecting moisture absorption of the insulator type lightning arrester, preferably, in the radiation step, terahertz waves of 0.1 terahertz or more and 0.7 terahertz or less are radiated.

  Preferably, in the moisture absorption detecting device for the insulator type lightning arrester, the radiation device emits a terahertz wave of 0.1 terahertz or more and 0.7 terahertz or less.

  The terahertz wave in this range is further transmitted through the insulator tube. Therefore, the detection accuracy of the internal moisture absorption state can be improved.

  The method of detecting moisture absorption deterioration of an insulator type lightning arrester according to the present invention includes a step of performing the moisture absorption detection method of the above insulator type arrester, and a determination step of determining deterioration of the insulator type arrester based on the moisture absorption state inspected by the inspection step. I have.

  According to the method for detecting moisture absorption deterioration of an insulator type lightning arrester according to the present invention, it is possible to check whether or not a liquid has entered the inside, so that moisture absorption deterioration of the insulator type arrester can be detected.

  According to the method for detecting moisture absorption of an insulator type lightning arrester and the moisture absorption detecting device for an insulator type arrester according to the present invention, it is possible to detect whether liquid such as moisture has entered the inside of the insulator type arrester by using terahertz waves.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  FIG. 1 is a schematic cross-sectional view showing a moisture absorption detection device for an insulator type lightning arrester according to an embodiment of the present invention. With reference to FIG. 1, the moisture absorption detection apparatus of the insulator type lightning arrester in embodiment of this invention is demonstrated. As shown in FIG. 1, the moisture absorption detection device 10 of the insulator type lightning arrester 100 according to the embodiment accommodates a zinc oxide element 101 containing zinc oxide as a main component and the remainder of inevitable impurities, and the zinc oxide element 101 therein. In addition, the moisture absorption detection device of the insulator type lightning arrester 100 including the insulator tube 102 made of insulator, and includes a radiation device 11, a detection device 12, and an analysis device 13. The radiation device 11 radiates terahertz waves to the outer surface of the insulator type lightning arrester 100. The detection device 12 receives the terahertz wave reflected from the zinc oxide element 101 and detects the waveform of the terahertz wave. The analysis device 13 compares and analyzes the waveform and the waveform in the normal state.

  In this specification, terahertz (THz) waves are millimeter waves (electromagnetic waves having a wavelength of 10 mm to 1 mm and a frequency of 30 GHz to 300 GHz) and far infrared rays (electromagnetic waves having a wavelength of 4 μm to 1000 μm and a frequency of 3 THz to 30 THz). Means that the frequency is in the range of 0.1 THz to 10 THz. In addition, the terahertz wave has a property of being transmitted through the insulator tube 102 and reflected by the zinc oxide element 101 and changing the waveform sensitively by a liquid such as moisture.

  Specifically, the radiation device 11 is not particularly limited as long as it is a device capable of emitting terahertz waves to the outer surface of the insulator type lightning arrester 100. For example, femtosecond pulsed light from a femtosecond laser is used as a radiation element called a terahertz emitter. When irradiated, terahertz waves are emitted. For the terahertz emitter, for example, a stripline type or dipole type optical transmission antenna is formed on a low temperature growth GaAs substrate, and a constant voltage is applied between terminals.

  The radiation device 11 is preferably a device that radiates terahertz waves of 0.1 terahertz to 0.7 terahertz. By using a device that emits a terahertz wave having a frequency in this range, a terahertz wave having a higher transmittance of the insulator tube 102 can be emitted.

  The detection device 12 is a device that receives a terahertz wave that is radiated from the radiation device 11, passes through the insulator tube 102, and is reflected from the zinc oxide element 101. And the radiation apparatus 11 detects the waveform (for example, time-resolved amplitude waveform) of the received terahertz wave. The detection device 12 is not particularly limited as long as it can receive the terahertz wave reflected from the zinc oxide element 101 and detect the waveform of the terahertz wave, but for example, the femtosecond pulsed light from the femtosecond laser is divided into two. One is irradiated to the radiating element and the other is irradiated to the detecting element. As the detection element, for example, a stripline type or dipole type optical transmission antenna is formed on a low-temperature grown GaAs substrate, and a constant voltage is applied between the terminals.

  The moisture absorption detection device 10 of the insulator type lightning arrester 100 may further include an analysis device 13 that compares and analyzes the waveform detected by the detection device 12 and the waveform in a normal state. The analysis device 13 may be a device that can also be used as the detection device 12.

  In addition, a normal waveform means the waveform which radiated | emitted the terahertz wave to the insulator type lightning arrester 100 in the initial state of the insulator type lightning arrester 100 by the radiation apparatus, and was detected by the detection apparatus.

  For example, the analyzer 13 superimposes a waveform detected by the detector 12 and a normal waveform, and indicates that the inside of the insulator type lightning arrester 100 is in a moisture absorbing state when the difference between the waveforms is larger than the noise. It is.

  In addition, it is preferable that the analyzer 13 further includes a control device that issues an alarm when the inside of the insulator type lightning arrester 100 is found to be in a hygroscopic state.

  The hygroscopic state means a state in which a liquid such as water is contained in the space 105 between the zinc oxide element 101 and the insulator tube 102 in an insulator type lightning arrester 100 described later.

  The insulator type lightning arrester 100 includes a zinc oxide element 101 and an insulator tube 102. The insulator-type lightning arrester 100 is a generally known one such as a porcelain insulator-type lightning arrester or a polymer-type lightning arrester, and includes known members such as a lid portion 103 and a bottom portion 104 in addition to the zinc oxide element 101 and the insulator tube 102. May be. The insulator type lightning arrester 100 is a structure including a member made of a metal material.

  The zinc oxide element 101 is mainly composed of zinc oxide, and the remainder is made of inevitable impurities. Specifically, the zinc oxide element 101 is made by sintering a powder of polycrystalline zinc oxide and is made of almost 100% zinc oxide.

  The insulator tube 102 contains the zinc oxide element 101 and the zinc oxide element 101 inside, and is made of an insulator. An insulator means what consists of the ceramics for electric insulation attached to a utility pole, a cubicle (distribution box), etc.

  In the insulator type lightning arrester 100, a space 105 is provided between the zinc oxide element 101 and the insulator tube 102. The space 105 is filled with, for example, dry air, nitrogen, or an inert gas. That is, the inside of the normal insulator type arrester 100 is kept dry.

  Next, with reference to FIG. 1, the moisture absorption detection method of the insulator type lightning arrester 100 in embodiment of this invention is demonstrated. The method of detecting moisture absorption of the insulator type lightning arrester 100 is an insulator type including a zinc oxide element 101 containing zinc oxide as a main component and the balance of inevitable impurities, and an insulator tube 102 containing the zinc oxide element 101 inside and an insulator. This is a method of detecting moisture absorption by the lightning arrester 100. The moisture absorption detection method of the insulator type arrester 100 is performed using the moisture absorption detection device 10 of the insulator type arrester 100 described above.

  First, a radiation process for radiating terahertz waves to the outer surface of the insulator type lightning arrester 100 is performed. In the radiation process, for example, a terahertz wave pulse is radiated from the outside of the insulator type lightning arrester 100 toward the outer surface.

  In the radiation process, it is preferable to emit a terahertz wave of 0.1 terahertz or more and 0.7 terahertz or less. By radiating terahertz waves in this range, it is possible to radiate terahertz waves having high transmittance of the insulator tube 102.

  The terahertz wave radiated from the radiation device 11 in the radiation process passes through the insulator tube 102 as shown by the arrow shown in FIG. 1, reflects off the surface of the zinc oxide element 101, and passes through the insulator tube 102 to obtain the insulator. It reaches the detection device 12 outside the lightning arrester 100.

  Next, a reception process for receiving the terahertz wave reflected from the zinc oxide element 101 is performed. In the reception step, for example, the terahertz wave pulse is received by the detection device 12 arranged outside the insulator type lightning arrester 100.

  Next, a detection step of detecting the waveform of the terahertz wave received in the reception step is performed. In the detection step, the waveform of the terahertz wave received every time can be detected, and a waveform such as an amplitude with respect to time (time-resolved amplitude waveform) can be detected.

  Next, an inspection process for inspecting the internal moisture absorption state is performed by comparing and analyzing the waveform detected in the detection process and the waveform in the normal state. In the inspection process, for example, the radiating process, the receiving process, and the detecting process are performed in advance in the normal state on the insulator type lightning arrester 100 that does not contain liquid (normal state) in advance. Measure the terahertz wave. The waveform of the terahertz wave in the normal state is an average waveform when measured multiple times in the normal state. And it compares with the waveform of the terahertz wave detected on the same conditions as the radiation | emission process at the time of measuring the terahertz wave waveform of the insulator type arrester 100 of a normal state, a receiving process, and a detection process. An arbitrary method can be adopted as the comparison method, but it can be easily analyzed by superimposing the waveform in the normal state and the measured waveform, for example.

  In the inspection process, for example, when a waveform in a normal state is compared with a measured waveform of a terahertz wave and a difference in waveform such as amplitude (time-resolved amplitude waveform) occurs, the inside of the insulator type arrester 100 It turns out that liquids such as moisture have invaded. Thereby, the moisture absorption state whether the inside of the insulator type lightning arrester 100 is absorbing moisture is detectable.

  Moreover, in the inspection process in the embodiment, the greater the moisture absorption inside the insulator type arrester 100, the greater the difference in amplitude between the normal state waveform and the measured terahertz wave waveform. Moreover, the site | part in which a liquid exists can be estimated from a time-resolved amplitude waveform. Therefore, it is possible to detect not only whether or not the inside of the insulator type lightning arrester 100 absorbs moisture but also the moisture absorption state such as the amount and location of liquid.

  Next, with reference to FIG. 1, the moisture absorption deterioration detection method of the insulator type arrester 100 in embodiment is demonstrated. In the method of detecting moisture absorption deterioration of the insulator type arrester 100, the step of determining deterioration of the insulator type surge arrester based on the moisture absorption state inspected by the inspection process after performing the above-described method of detecting moisture absorption of the insulator type arrester. To implement.

  In the determination process, for example, when the inside of the insulator type lightning arrester 100 detected in the inspection process absorbs moisture, it is determined that the insulator type arrester 100 has deteriorated. In the determination step, it may be determined that the insulator type lightning arrester 100 has deteriorated based on any appropriate moisture absorption state.

  As described above, according to the moisture absorption detection method of the insulator type lightning arrester 100 according to the embodiment, the zinc oxide element 101 having zinc oxide as a main component and the balance of inevitable impurities, and the zinc oxide element 101 are accommodated therein. In addition, a method for detecting moisture absorption of the insulator type arrester 100 including the insulator tube 102 made of insulator, and a radiation step of radiating a terahertz wave to the outer surface of the insulator type arrester 100, and a terahertz wave reflected from the zinc oxide element 101 are performed. By comparing and analyzing the receiving step for receiving, the detecting step for detecting the waveform of the terahertz wave received in the terahertz wave receiving step, the waveform detected in the detecting step, and the waveform in the normal state, And an inspection process for inspecting the moisture absorption state. As a result of intensive studies by the inventor of the present application, it has been found that terahertz waves are used when detecting whether or not a liquid such as moisture has entered the inside of the insulator type arrester 100. That is, the insulator type lightning arrester 100 is utilized by utilizing a terahertz wave having a property of being relatively transmitted through the insulator tube 102 and relatively reflecting on the surface of the internal zinc oxide element 101 and sensitive to a liquid such as moisture. It has been found that liquid such as moisture entering the inside of the can be detected. Therefore, when a terahertz wave is radiated to the outer surface of the insulator type lightning arrester 100 by the radiation process, it is transmitted through the insulator tube 102 and reflected by the surface of the zinc oxide element 101. The detection process detects whether or not the liquid has entered the insulator type lightning arrester 100 by comparing the waveform of the reflected terahertz wave with the waveform of the terahertz wave when the liquid does not contain the liquid. can do. That is, according to the moisture absorption detection method of the insulator type lightning arrester 100, not only can the abnormality of the insulator type lightning arrester 100 be diagnosed, but the cause of the abnormality in the insulator type lightning arrester 100 can be specified as moisture intrusion into the interior.

  In the above-described method of detecting moisture absorption of the insulator type lightning arrester, preferably, in the radiation step, terahertz waves of 0.1 terahertz or more and 0.7 terahertz or less are radiated. The terahertz wave in this range is further transmitted through the insulator tube 102. Therefore, the detection accuracy of the moisture absorption state inside the insulator type lightning arrester 100 can be improved.

  The method of detecting moisture absorption deterioration of the insulator type lightning arrester 100 according to the embodiment of the present invention includes a step of performing the moisture absorption detection method of the insulator type arrester 100 and a deterioration of the insulator type arrester 100 based on the moisture absorption state inspected by the inspection step. And a determination step of determining Thereby, since it can be confirmed whether the liquid has penetrate | invaded the inside of the insulator type lightning arrester 100, the moisture absorption deterioration of the insulator type lightning arrester 100 can be detected.

  According to the moisture absorption detection device 10 of the insulator type lightning arrester 100 according to the embodiment of the present invention, the zinc oxide element 101 composed mainly of zinc oxide and the remainder of inevitable impurities, the zinc oxide element 101 are accommodated inside, and the insulator is contained. A moisture absorption detection device 10 of an insulator type lightning arrester 100 including an insulator tube 102 made of the above, and a radiation device 11 that radiates a terahertz wave to the outer surface of the insulator type lightning arrester 100, and a terahertz wave reflected from the zinc oxide element 101. A detection device 12 that receives and detects the waveform of the terahertz wave, and an analysis device 13 that compares and analyzes the waveform and the waveform in a normal state are provided. When a terahertz wave is radiated from the outside of the insulator type lightning arrester 100 by the radiating device 11, it is transmitted through the insulator tube 102 and reflected by the surface of the zinc oxide element 101 due to the nature of the terahertz wave. The detector 12 and the analyzer 13 compare the reflected terahertz wave waveform with the terahertz wave waveform when no liquid is contained therein, so that the liquid enters the insulator type arrester 100. It can be detected whether or not.

  In the moisture absorption detection device 10 of the insulator type lightning arrester 100, the radiation device 11 preferably emits a terahertz wave of 0.1 terahertz or more and 0.7 terahertz or less. The terahertz wave in this range is further transmitted through the insulator tube 102. Therefore, the detection accuracy of the moisture absorption state inside the insulator type lightning arrester 100 can be improved.

[Example 1]
In Example 1, it confirmed that a terahertz wave permeate | transmits an insulator tube. Specifically, samples of 1 cm × 1 cm × 2 mm were prepared for two places of the insulator tube. The glaze was applied to the surface side of the insulator tube. Specifically, sample A was on the back side (without glaze), sample B was on the front side (with glaze), sample C was on the back side (without glaze), and sample D was on the front side (with glaze).

  And about the samples AD, the terahertz wave of a different frequency was radiated | emitted and the light absorption coefficient was measured. For the measurement of the extinction coefficient, the apparatus shown in FIG. 2 was prepared and the apparatus was used. Further, as shown in FIG. 3, the radiating element and the detecting element used were elements in which a dipole antenna was formed on a GaAs substrate grown at a low temperature. The measurement results are shown in FIG. FIG. 2 is a schematic view showing the apparatus used in Example 1. FIG. 3 is a schematic diagram illustrating the transmission-type radiation device and detection device used in the first embodiment. FIG. 4 is a diagram showing extinction coefficients when various terahertz tubes are irradiated with terahertz waves. In FIG. 4, the horizontal axis indicates the frequency of the irradiated terahertz wave (unit: THz), and the vertical axis indicates the extinction coefficient (unit: none).

  As shown in FIG. 4, it was confirmed that the terahertz wave was transmitted through the insulator tube without being influenced by the glaze of the insulator tube. Moreover, in Example 1, it has confirmed that the transmittance | permeability to the insulator tube of the terahertz wave whose frequency is 0.7 THz or less was especially good.

[Example 2]
In Example 2, it was confirmed that the terahertz wave is relatively reflective to the zinc oxide element and relatively difficult to transmit.

  And the apparatus shown in FIG. 2 was produced and the transmittance | permeability was measured using the said apparatus. Moreover, the apparatus shown in FIG. 5 was produced and the reflectance was measured using the apparatus. Further, as shown in FIG. 3, the radiating element and the detecting element used were elements in which a dipole antenna was formed on a GaAs substrate grown at a low temperature. The measurement results are shown in FIG. FIG. 5 is a schematic diagram illustrating the reflection type radiation device and detection device used in the second embodiment. Moreover, FIG. 6 is a figure which shows the transmittance | permeability and reflectance when a zinc oxide element is irradiated with a terahertz wave. In FIG. 6, the horizontal axis indicates the frequency (unit: THz) of the irradiated terahertz wave, and the vertical axis indicates the transmittance and the reflectance (unit: none).

  As shown in FIG. 6, it was confirmed that the terahertz wave hardly transmitted through the zinc oxide element. It was also found that the reflectance of the terahertz wave to the zinc oxide element was high. In Example 2, the reflectance of the terahertz wave having a frequency of 0.7 THz or less exceeded 0.45, and it was confirmed that the reflectance was particularly good.

[Example 3]
In Example 3, it was confirmed that the moisture absorption state of the insulator type surge arrester can be detected by the moisture absorption detection method of the insulator type arrester of the present invention. FIG. 7 is a schematic cross-sectional view showing the measuring apparatus used in Example 3. FIG. 8 is a top view showing the insulator used in the third embodiment. FIG. 9 is a top view when a sample in which water is condensed on the zinc oxide element so as to have a dew diameter of 1 mm is set in a measuring apparatus. FIG. 10 is a top view when a sample in which water is condensed on the zinc oxide element so as to have a dew condensation diameter of 0.5 mm is set in a measuring apparatus.

  Specifically, the measurement was performed by the measuring apparatus 200 shown in FIG. The measuring apparatus 200 arranges a 20 mm × 20 mm × 2 mm sample zinc oxide element 101 on a first acrylic plate 201 of 20 mm × 20 mm × 1 mm, and has a thickness of 1 mm on a pair of opposite sides of the zinc oxide element 101. A second acrylic plate 202 was placed, and a 15 mm × 15 mm × 2 mm insulator 203 was placed on the second acrylic plate 202. In addition, the insulator 203 used the insulator which comprises the insulator pipe | tube shown in FIG. In the measuring apparatus 200, each member was connected with a double-sided tape.

  Further, the sample zinc oxide element 101 includes a sample in which water is condensed on the surface of the zinc oxide element by spraying as shown in FIG. 9 to a dew diameter of 1 mm, and a zinc oxide element as shown in FIG. A sample in which water was condensed so that the condensation diameter was 0.5 mm by spraying on the surface and a normal sample in which no water droplets were present on the surface of the zinc oxide element were placed in the measuring apparatus 200.

  And about each sample, the terahertz wave was radiated | emitted, the reflected terahertz wave was received, the waveform was detected, and it test | inspected. In addition, the thing similar to Example 1 was used for the radiation | emission apparatus and the detection apparatus. The results are shown in FIG. 11 and FIG. FIG. 11 is a diagram illustrating the amplitude of the terahertz wave with respect to the irradiation time. In FIG. 11, the horizontal axis represents time (unit: ps), and the vertical axis represents amplitude (unit: none). FIG. 12 is an enlarged view of the region R in FIG. In FIG. 12, the horizontal axis indicates time (unit: ps), and the vertical axis indicates amplitude (unit: none).

  As shown in FIGS. 11 and 12, the sample in which water droplets were condensed only on the surface side of the zinc oxide element had a waveform change on the surface as compared with the waveform in the normal state. On the other hand, the waveform on the back side of the zinc oxide element in which no water droplets were condensed was almost the same as the waveform in the normal state. From this result, it was confirmed that by radiating terahertz waves, it was possible to detect whether or not a liquid such as a water droplet was present inside the insulator type arrester.

  In addition, the sample with a condensation diameter of 1 mm had a larger deviation from the normal waveform than the sample with a condensation diameter of 0.5 mm. From this result, it was confirmed that the amount of liquid such as water droplets present inside the insulator type arrester can be detected.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above-described embodiment but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

  According to the method of detecting moisture absorption of the insulator type arrester and the method of detecting moisture absorption of the insulator type arrester according to the present invention, it is possible to detect the moisture absorption state inside the insulator type arrester, so that the insulator type arrester installed in a power plant or substation can be used. Accidents due to moisture absorption deterioration can be prevented.

It is a schematic sectional drawing which shows the moisture absorption detection apparatus of the insulator type lightning arrester in embodiment of this invention. 1 is a schematic view showing an apparatus used in Example 1. FIG. 1 is a schematic diagram showing a transmission type radiation device and a detection device used in Example 1. FIG. It is a figure which shows the light absorption coefficient when a terahertz wave is irradiated to various insulator tubes. It is the schematic which shows the reflection type radiation | emission apparatus and detection apparatus which were used for Example 2. FIG. It is a figure which shows the transmittance | permeability when a terahertz wave is irradiated to a zinc oxide element. 6 is a schematic cross-sectional view showing a measuring apparatus used in Example 3. FIG. It is a top view which shows the insulator used in Example 3. It is a top view when the sample which water-dewed so that the dew condensation diameter might be set to 1 mm to a zinc oxide element was set to the measuring apparatus. It is a top view when the sample which water-condensed the zinc oxide element so that a dew condensation diameter may be set to 0.5 mm is set to the measuring apparatus. It is a figure which shows the amplitude of the terahertz wave with respect to the irradiation time. It is the figure which expanded the area | region R in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Moisture absorption detection apparatus, 11 Radiation apparatus, 12 Detection apparatus, 13 Analysis apparatus, 100 Insulator type lightning arrester, 101 Zinc oxide element, 102 Insulator tube, 103 Cover part, 104 Bottom part, 105 Space, 200 Measuring apparatus, 201 1st acrylic Plate, 202 second acrylic plate, 203 insulator.

Claims (5)

A method for detecting moisture absorption of an insulator type lightning arrester comprising a zinc oxide element comprising zinc oxide as a main component and the balance being an inevitable impurity, and an insulator tube containing the zinc oxide element therein and an insulator tube,
A radiation process for radiating terahertz waves to the outer surface of the insulator type arrester;
Receiving the terahertz wave reflected from the zinc oxide element;
A detection step of detecting a waveform of the terahertz wave received in the reception step;
A method for detecting moisture absorption of an insulator type lightning arrester, comprising: an inspection step of inspecting an internal moisture absorption state by comparing and analyzing the waveform and a waveform in a normal state.   The method for detecting moisture absorption of an insulator type lightning arrester according to claim 1, wherein the terahertz wave of 0.1 terahertz to 0.7 terahertz is radiated in the radiation step. The step of performing the moisture absorption detection method of the insulator type lightning arrester according to claim 1 or 2,
And a determination step of determining deterioration of the insulator type arrester based on the moisture absorption state inspected by the inspection step. A moisture absorption detection device for an insulator-type lightning arrester including a zinc oxide element composed mainly of zinc oxide and the balance of inevitable impurities, and an insulator tube containing the zinc oxide element inside and an insulator tube,
A radiation device that emits terahertz waves on the outer surface of the insulator type arrester;
A detector that receives the terahertz wave reflected from the zinc oxide element and detects the waveform of the terahertz wave;
An apparatus for detecting moisture absorption of an insulator type lightning arrester, comprising: an analyzer that compares and analyzes the waveform and a waveform in a normal state.   The said radiation device radiates | emits the said terahertz wave of 0.1 terahertz or more and 0.7 terahertz or less, The moisture absorption detection apparatus of the insulator type lightning arrester of Claim 4 characterized by the above-mentioned.