JP3104711B2 - Method and apparatus for detecting defective insulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for detecting a defective insulator, and more specifically, to power transmission of an overhead transmission line or the like.
From insulator holding wire to defective insulator (defective insulator or dirty insulator)
And a method and apparatus for detecting a child .

[0002]

2. Description of the Related Art A method and an apparatus for detecting an abnormal portion of an overhead power transmission line (including a sleeve, a spacer and a damper) and its facilities (a steel tower, an insulator, etc.) by corona discharge are disclosed.
1988 Patent Application Publication No. 503324 (PCT / C
H86 / 00066). In the method disclosed in this publication, a helicopter is caused to fly along an aerial wire, a radio wave in a band of 20 MHz to 200 MHz is received by a corona discharge detection antenna mounted on the helicopter, and a waveform on an oscilloscope (the same publication) is used. Fig. 5-
(FIG. 9) to determine and detect a defective portion.

[0003]

However, in the above conventional example, the measurement frequency band is mainly 20 MHz to 200 MHz.
Therefore, it is necessary to use a high-speed and expensive circuit element in each section.

In the above-described conventional example, the presence or absence and the content of the abnormality are determined from the disturbance of the waveform of the oscilloscope. However, since the corona signal is generated at a speed of several tens of μs, such a determination method quantitatively determines the content of the abnormality. And it is difficult to judge objectively. Since the judgment is made by human eyes, there is an individual difference, a judgment difference every day, or a time zone, and thus it is inaccurate. It is also difficult to identify the location of the abnormality.

For example, in an ultra-high voltage transmission line facility, 15 or more insulators are used. For example, even if an insulator located in the middle of the insulator has a failure, it cannot be specified and detected. In addition, when the wires of the overhead power transmission line are partially broken near the insulator portion of the power transmission tower, it is difficult to determine whether the abnormal location is the insulator or the overhead power transmission line and to specify the abnormal location.

[0006] The present applicant has disclosed a method for solving these problems on February 14, 1990 (Japanese Patent Application No. 33544/1990).
No.).

In the method and apparatus according to the patent application, it was difficult to objectively grasp the abnormality. In particular, with regard to the failure and contamination of the insulation insulator of the transmission line tower, there is a problem that it is difficult to discriminate from a measured value whether it is a sound insulator or a defective / dirty insulator unless a very skilled person.

The present invention solves such a problem.
An object of the present invention is to provide a method and an apparatus for detecting a defective insulator (defective insulator or dirty insulator) .

[0009]

According to the present invention, there is provided a defect insulator according to the present invention.
The detection method is from the insulator holding the transmission line to the defective insulator (defective
(Insulators or contaminated insulators)
Line and a receiving station for receiving radio waves radiated from the insulator.
And a predetermined band component from the reception result of the reception step.
Extraction step, and the extraction result of the extraction step
From the result, the maximum value and the average
From the average calculation step and the reception result of the reception step
A sudden wave detecting step of detecting a sudden wave;
From the reception result of the
Extract the component and determine the basics when the sudden wave is detected.
A fundamental peak value detecting step of detecting a peak value of a wave component,
Maximum value and average calculated in the maximum average calculation step
Values, and are detected in the fundamental peak value detection step.
Determining a defective insulator from the peak value.
It is characterized by having. Detection of defective insulator according to the present invention
The device detects defective insulators from the insulator holding the transmission line
Device radiated from the transmission line and the insulator
Receiving means for receiving radio waves, and the reception result of the receiving means
Extraction means for extracting a predetermined band component from the
Detect the maximum value and average value within a predetermined time from the extraction result
From the maximum average calculating means and the receiving result of the receiving means.
Sudden wave detection means for detecting an emitted wave, and reception of the reception means
Extract the fundamental component of the current flowing through the transmission line from the result
And the wave of the fundamental wave component when the sudden wave is detected
A fundamental peak value detecting means for detecting the peak value, and the maximum average calculation
Maximum and average values calculated by the
From the peak value detected by the peak value detecting means, a defective insulator is obtained.
Computing means for calculating the determination value of
I do.

[0010]

The value obtained by the above calculation shows a remarkably different numerical value for defective / dirty insulators as compared with healthy insulators. Therefore, almost 100% of defective / dirty insulators can be objectively determined without causing individual differences.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the corona discharge is measured by an apparatus basically similar to the apparatus described in the above-mentioned Japanese Patent Application No. 33544. In the present embodiment, the measured value is analyzed by a unique method, and an evaluation value that can clearly discriminate a defective / dirty insulator from a healthy insulator is calculated.

[0013] In the overhead power transmission line and its equipment, a constant corona discharge is generated even in the normal case, but the corrosion and dirt of the wire,
Local abnormal corona discharge occurs due to defects or abnormalities such as broken wires, defective insulators (cracks, moisture absorption, etc.) or contamination (dirt, rain leaks, etc.). Radio waves due to the abnormal corona discharge and radio waves due to the propagating power are radiated to the surroundings. As described in Japanese Patent Application No. 33544/1990, it has been found that the above-mentioned defect or abnormality can be detected by relatively low frequency (up to about 10 KHz) radio waves from overhead transmission lines and their facilities.

Further, the frequency of the radio wave due to the power propagating through the overhead transmission line is the frequency of the power (50 Hz or 60H).
z, hereinafter referred to as the fundamental wave), and its amplitude is generally proportional to the propagating power. As a result of the observation, it was found that the amplitude of the radiated radio wave due to the propagation power was affected by the grounding fault of the tower. That is, from the amplitude of the fundamental wave component of the radio wave from the overhead transmission line and its equipment, it is possible to determine the presence or absence and the degree of the trouble of the tower.

FIG. 1 and FIG. 2 are schematic block diagrams of an embodiment of the present invention. FIG. 1 shows equipment mounted on a helicopter. In FIG. 1, reference numeral 10 denotes a measurement antenna for receiving the electric wave radiated from the overhead power transmission line and its equipment. In the present embodiment, the measurement antenna 10 is 50 to 60H
Any antenna that can receive a radio wave from the fundamental wave of z to at most about 10 KHz may be used.

Reference numeral 12 denotes a radio range finder for measuring a distance to a measurement object (an overhead transmission line and its equipment) by a radio system. In this embodiment, as the radio rangefinder 12, a rangefinder JRA-100 manufactured by Japan Aviation Electronics Industry, Ltd. was used. This rangefinder JRA-100 has a transmission frequency of 4.3G.
The distance to the target is measured by radiating a pulsed radio wave of Hz to the target and receiving the reflected radio wave from the target. The distance meter JRA-100 can measure a distance with an accuracy of ± 2 feet in a distance range intended in the present embodiment.

Reference numeral 14 denotes a position and ground speed meter for measuring the position of the helicopter and the ground speed.
(Global Positioning System). 16 is a fixed point whose ground position is known (for example,
This is a position fixing marker that generates a fixing mark signal for a tower, a sleeve, a spacer, a damper, etc. that supports an overhead transmission line. The position fixing marker 16 includes a plurality of switches that individually generate different voltages so that a plurality of fixed points can be distinguished later. The position fixing marker 16 makes it easy to confirm the ground position when analyzing the measurement data. By the outputs of the ground speed meter 14 and the position fixing marker 16, the flight position, that is, the measurement position can be accurately known.

Reference numeral 18 denotes a measuring antenna 10, a radio range finder 1
2. An interface circuit that performs signal conversion for recording signals from the ground speed meter 14 and the position fixed marker 16 on the data recorder 20. In the interface circuit 18, an amplifier 92 amplifies a weak radio wave received by the measurement antenna 10 into an input voltage range of the data recorder 20, an amplifier 94 amplifies an output voltage of the radio rangefinder 12, and 96 an earth speed meter 14. , 98 is a low-pass filter (LPF) for extracting a low-frequency component of the output of the amplifier 92, and 100 is a pulse generation circuit for generating a pulse signal of a voltage corresponding to the button number of the position fixing marker 16. is there.

The data recorder 20 is, for example, a digital audio tape recorder which has a plurality of recording channels and digitally records the measurement signals and output data of the above-described elements on a magnetic tape 22.

A helicopter equipped with the equipment shown in FIG. 1 is hovered at a fixed distance from an insulator of a steel tower to be searched for abnormalities, and the distance between the helicopter and the overhead transmission line is measured by a radio range finder 12. Measurement antenna 1
According to 0, the radio wave from the tower is measured for an appropriate period. The data recorder 20 is turned on in advance and put into the recording pause state. During the measurement period, the recording pause of the data recorder 20 is released, and the received radio wave data is transmitted to the data recorder 20.
Is digitally recorded on the magnetic tape 22. at the same time,
The distance data to the measurement point output from the radio rangefinder 12, the output from the ground speed meter 14, and the position information from the position fixing marker 16 are also digitally recorded on the individual data channels of the magnetic tape 22 of the data recorder 20.

It is desirable that the distance between the helicopter and the insulator (or steel tower) to be measured is constant.
As will be described later, in this embodiment, the radio wave attenuation due to the distance is corrected, so that even if the distance between the helicopter and the insulator fluctuates, the defective / dirty insulator can be appropriately detected.

The magnetic tape 22 on which the measurement data is recorded is reproduced on the ground, and the measured radio wave data is analyzed by a computer and graphed. In addition, an evaluation value for discriminating a defective / dirty insulator is calculated by statistical processing.

FIG. 2 is a block diagram showing the configuration of the analytical plotting device arranged on the ground. In FIG. 2, reference numeral 24 denotes a reproducing device for reproducing the data recorded on the magnetic tape 22, and reference numeral 90 denotes a computer in charge of analysis processing. The reproducing device 24 outputs the measured radio wave data by the measuring antenna 10 to the output signal line 24a, the transmission line distance data by the distance measuring device 12 to the output signal 24b, the position mark data by the position fixing marker 16 to the output signal line 24c, The ground speed data from the ground speed meter 14 is output to the output signal line 24d.

The distance data of the signal line 24b is input to a statistical processing circuit 26, where it is statistically processed. In particular,
An extreme value of the distance data is eliminated and its fluctuation is smoothed. The voltage conversion circuit 28 converts the distance data output from the statistical processing circuit 26 into a voltage signal having a voltage value corresponding to the distance value.

The distance correction circuit 30 outputs the output of the voltage conversion circuit 28, that is, the antenna 10 and the object to be observed (insulator or steel tower).
The measured radio wave data on the signal line 24a is corrected to an intensity at a predetermined fixed distance in accordance with the distance value between. Even if the helicopter is hovered near the tower, it is practically impossible to keep the distance to the tower constant. Radio waves radiated from the tower and its vicinity are theoretically inversely proportional to the square of the distance. Therefore, the measured radio wave data is corrected to a value at a fixed distance based on the distance data measured at the same time. Also, without performing the correction by such a theoretical formula, the attenuation characteristic due to the distance is actually measured, and the measured radio wave data is applied to the attenuation characteristic function obtained by the measurement, so that the value is corrected to a value at a certain distance. Is also good. In any of the correction methods, the distance correction circuit 30 is practically constituted by a digital arithmetic circuit, so that it is easy to realize.

The measured radio wave data whose distance has been corrected by the distance correction circuit 30 is supplied via a buffer memory 32 to a fast Fourier transform circuit (FFT) 34 and a sudden wave detection circuit 36.
Supplied to In this embodiment, the buffer memory 32 applies 4,096 pieces of measured radio wave data to the sudden wave detection circuit 36 at a time, for the sake of processing capacity, and stores 2,048 pieces of data from the head of 4,096 pieces of data. It is supplied to the fast Fourier transform circuit 34. The fast Fourier transform circuit 34 divides the measured radio wave data into 22 frequency channels and outputs them.

FIG. 7 shows the frequency band of the output channel of the fast Fourier transform circuit 34. However, it should be understood that this is merely an example, and the present invention is not limited to such frequency division. Note that the frequency band up to CH8 may be checked at most for detecting insulator failure / dirt.

Since the output of the distance correction circuit 30 has been corrected for distance, as long as the ground resistance of the tower of the overhead power transmission line is appropriate, the fast Fourier transform circuit 34 and the sudden wave detection circuit 36
Of the input signal, a noise component and an abrupt component due to corona discharge partially generated due to a broken wire, a defective insulator or the like are superimposed on a fundamental wave having a substantially constant amplitude of 50 Hz or 60 Hz. Signal waveform. The sudden wave detection circuit 36 is a circuit that detects such a sudden wave superimposed on the fundamental wave. The internal configuration of the sudden wave detection circuit 36 is as follows.
Details will be described later. The sudden wave detection circuit 36 outputs a signal indicating the timing of the detected sudden wave (that is, the occurrence position), the peak value, the duration, and the number of occurrences in the processing section (4,096 data).

A signal line 24c output from the reproducing device 24
The upper position mark data is applied to the mark extraction circuit 38. The mark extraction circuit 38 receives the position mark
From the data, for example, a position mark data of a thing whose ground position is known, such as a steel tower, is extracted, and a corresponding pulse signal is generated.

The speed data on the signal line 24d output from the reproducing device 24 is input to a statistical processing circuit 42, where it is subjected to statistical processing. The output of the statistical processing circuit 42 is converted into a voltage signal by the voltage conversion circuit 44.

The overhead transmission line and its equipment have problems such as defects existing over a certain long distance due to corrosion and aging of the overhead transmission line, poor grounding resistance of the tower, broken wires and poor insulation of the insulator. There is a failure or abnormality that occurs at a specific site. The former appears as a low-frequency noise component that is superimposed on the fundamental wave of 50 or 60 Hz over a certain length along the overhead power transmission line in the measured radio wave data (for example, the output of the distance correction circuit 30), and the latter appears. Appears as a sudden wave superimposed at a position corresponding to a failure or an abnormal part or a fluctuation component in a short section.

As a result of the observation, such a noise component implies that the overhead transmission line is aging or needs to be replaced.
Hz and a frequency band of 5 to 6 kHz. Therefore, the abnormality degree determination circuit 46 is a circuit that indicates, as an index, an abnormality detection time, a replacement time, and the like of the overhead transmission line and its equipment. FIG. 3 shows the internal configuration of the abnormality degree determination circuit 46.

In FIG. 3, a dividing circuit 52 divides the peak height of the sudden wave by the amplitude of the fundamental wave, and an indexing circuit 54 divides the output value of the dividing circuit 52 into, for example, four steps of 1, 2, 3, and 4. Apply to the segment and output an index value indicating the corresponding segment.
From this index value, it is possible to objectively determine whether urgent on-site inspection, continuous monitoring, or immediate monitoring is unnecessary.

Each frequency component of the measured radio wave data (output of the fast Fourier transform circuit 34), the height and width of the sudden wave, the number of sudden waves per unit processing section, the peak value of the fundamental wave at the sudden wave occurrence position, etc. (The output of the sudden wave detection circuit 36),
The output of the abnormality degree determination circuit 46, the distance value to the transmission line (the output of the voltage conversion circuit 28), and the fixed position mark are input to a plotting device 48 such as a plotter or a printer, and the measurement time elapses (that is, the measured overhead). Along the transmission line),
Each measurement and analysis data value is printed and graphed on paper. In addition to the above data, the flight speed data (output of the voltage conversion circuit 44) is also added to the data recording device 49 for detecting defective insulators and fouling, as well as re-analyzing and performing more detailed analysis later. Recording is performed on a recording medium, for example, a magneto-optical disk.

FIG. 4 shows an output example of the plotter 48. However, the output of the sudden wave detection circuit 36 (the number, width, and height of the sudden wave and the cut level for detecting the sudden wave), the distance to the transmission line, and CH1 of the fast Fourier transform circuit 34
Only the outputs of .about.15 are shown. The fixed line is a position reference line based on a fixed position mark signal based on the output of the mark extraction circuit 38.

FIG. 5 is a block diagram showing the circuit configuration of the sudden wave detection circuit 36, and FIG. 6 is a waveform diagram in the process of separating the sudden wave and calculating the position of occurrence of the sudden wave. For ease of understanding, FIG. 6 shows the signal in the form of an analog signal. As described above, the sudden wave detection circuit 36 includes:
Data is supplied from the buffer memory 32 in units of 4,096 pieces. The input signal waveform of the sudden wave detection circuit 36 is shown in FIG.
As illustrated in (a), the waveform has a waveform in which a noise and a sudden wave caused by corona discharge caused by a defect / fouling of the insulator or a broken wire are superimposed on a fundamental wave of 50 or 60 Hz.

The data from the buffer memory 32 is converted by a digital low-pass filter (LPF) 60 and a digital high-pass filter (HPF) 62 into a fundamental wave component and a frequency component higher than the fundamental wave and not including the fundamental wave. Is separated into That is, the LPF 60 is 50-60 Hz.
Is a digital filter for extracting the fundamental component of the fundamental wave.
It is a digital filter that extracts components above Hz.

The output of the HPF 62 has a waveform composed of noise and sudden waves, for example, as shown in FIG. FIG.
FIG. 7C is an enlarged view of FIG. Peak detection circuit 6
Numeral 4 detects positive and negative peak values from the output of the HPF 62, and an absolute value circuit 66 converts the peak value detected by the peak detection circuit 64 into a positive value. The output of the HPF 62 may be converted into an absolute value first, and then the peak may be detected. The peak detected by the peak detection circuit 64 includes both a sudden wave and noise. The statistical processing circuit 68 performs a statistical calculation on the positive peak value output from the absolute value circuit 66 to reduce the variation of the data and, if necessary, a high frequency component to remove a predetermined high frequency component. Is calculated. The calculated noise level is applied to the noise cut circuit 70.

The output of the HPF 62 is also supplied to an absolute value circuit 72.
The negative value is converted to a positive value by the
Is applied to The noise cut circuit 70 subtracts the noise level from the statistical processing circuit 68 from the output data of the absolute value circuit 72. By this subtraction processing, the output of the noise cut circuit 70 includes only the sudden wave.
FIG. 6D shows an output signal waveform of the noise cut circuit 70. The output of the noise cut circuit 70 is applied to the sudden wave calculation circuit 76. The sudden wave calculation circuit 76 generates a noise
From the output of the cut circuit 70, the location, height,
The number of sudden waves per processing section (4,096 pieces of data) and the generation period (ie, width) of closely adjacent sudden waves are calculated.

The fundamental wave height calculating circuit 78 is a circuit for calculating the peak value of the fundamental wave at the position where the sudden wave occurs. More specifically, for example, the sudden wave generating timing signal from the sudden wave calculating circuit 76 is sampled by a sampling clock. As LPF
60 outputs are sampled. The fundamental crest value calculated by the fundamental crest calculation circuit 78 is applied to the output circuit 80. The output circuit 80 is also supplied with data relating to the sudden wave calculated by the sudden wave calculation circuit 76, and the output circuit 80 outputs these data to the plotting device via individual signal lines or bus-type signal lines. 48 and data recording device 49
Output to The output circuit 80 functions as an output buffer and a circuit for adjusting the output timing of each data to be output.

As described in Japanese Patent Application No. 33544/1990, each frequency component of the measured radio wave basically changes as follows with respect to the failure of the overhead transmission line and its facilities. That is, if there is corrosion or dirt on the wires of the overhead transmission line,
The level increases the noise level. If a strand breaks, a sharp sudden wave is generated depending on the degree, and the width of the sudden wave changes depending on the scale. Further, when the ground resistance of the tower is poor, the level of the fundamental wave changes, and the level changes in other frequency bands. For example, in FIG. 4, A and B (both CH1) indicate a failure in the grounding resistance of the tower, C (CH4) and D (CH12) indicate corrosion or dirt of the wire, and the sudden wave in the sudden wave detection result. Implies that there is a sleeve or spacer at that position, or that there is a broken wire.

Insulator defect factors include internal factors such as cracks and moisture absorption, and external factors such as dirt and rain leakage. In this specification, those having the former defect are referred to as defective insulators. Those with the latter defect are called fouling insulators.

The tendency of the measured value (distance correction value) of each channel for these defective / dirty insulators was examined. FIG. 8 shows the results of measuring and comparing defective insulators, dirty insulators and sound insulators in a factory. The horizontal axis is the frequency (channel), and the vertical axis is the difference between the maximum value of the measured value of the defective / dirty insulator (that is, the output of the FFT 34) and the maximum value of the measured value of the healthy insulator. Solid lines indicate defective insulators,
Dashed lines indicate fouling insulators.

As can be seen from FIG. 8, regarding the defective insulator, CH4 shows a remarkable difference as compared with the healthy insulator. Therefore,
After examining this more clearly and using it for objective judgment, the defective insulator was objectively determined by dividing the difference between the maximum value and the average value by the abnormal wave height (fundamental wave height at the time of the sudden wave occurrence). It was found that it was possible to make a distinction. The calculation formula of the evaluation value is as follows. That is, S1 = {(Amax−Aav) / Ah} / ｛(Bmax
−Bav / Bh)｝ where Amax: maximum value of defective / dirty insulator Aav : average value of defective / dirty insulator Ah: abnormal peak value of defective / dirty insulator Bmax: maximum value of healthy insulator Bav: average value of healthy insulator Bh: Abnormal peak value of sound insulator. FIG. 9 shows the above S1 by the test in the factory.
In FIG. 9, the horizontal axis represents frequency (channel), and the vertical axis represents the evaluation value S1. Solid lines indicate defective insulators. Since S1 of CH4 greatly exceeds 1, defective insulators can be easily determined.

In actual use sites, it is difficult to obtain a measurement value of only a healthy insulator, but generally, only a part of a large number of insulators in a measurement range has a defect or contamination. Therefore, at the time of the site survey, the overall average of the measured values was regarded as the value of the sound insulator, and the evaluation value S1 was calculated by the above evaluation formula. FIG. 10 shows an example of the measurement result. In FIG. 10, the horizontal axis is frequency (channel), the vertical axis is frequency (channel), and the vertical axis is a value obtained by normalizing (maximum value−average value) / abnormal peak value of each tower with its overall average value. . The solid line is a tower with defective insulators, and the dashed line is a tower with healthy insulators. In addition, climbing each tower from the ground, and measuring the shared voltage for each insulator during high-voltage transmission, it was confirmed whether the insulator is defective or sound. When we surveyed more than 200 towers,
100% of defective insulators could be detected.

FIG. 9 shows the evaluation value S1 of the fouled insulator by a broken line for reference. As can be seen from FIG.
Then, the flawed insulator cannot be clearly distinguished. Referring to FIG. 8, since CH2 becomes significantly larger for the fouled insulator,
2 allows the soiled insulator to be determined. In the ground experiment, CH2
(Average) showed a positive correlation with the degree of fouling. Since a fouled insulator is also generally considered to be only a part of a large number of insulators to be installed, similarly to the case of a faulty insulator, by standardizing the average value of the entire measurement range,
The fouled insulator can be objectively determined. In order to obtain an evaluation value from which defective insulators are removed, for example, the average value of CH2 is calculated as CH
The value obtained by dividing by the average value of 4 may be used.

The evaluation value calculation circuit 102 performs an arithmetic operation on the measured value recorded in the large-capacity data recording device 49 and outputs the above-mentioned evaluation value. If the evaluation value exceeds a predetermined value, it can be estimated that a defective insulator or a dirty insulator exists.

The present invention is not limited to the configuration of the above embodiment. For example, it is easy to realize a part or all of the circuit blocks shown in the drawings by one or a separate digital processing unit, and it is needless to say that these are also included in the technical scope of the present invention.

The evaluation value calculation circuit 102 calculates the evaluation value for determination by calculating the measurement value once recorded on the recording medium, but may output the value in real time.

[0050]

As can be easily understood from the above description, according to the present invention, defective and / or dirty insulators can be objectively detected. Accordingly, automatic detection of defective / dirty insulators becomes possible, and the investigation can be performed more easily and in a shorter time.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of an on-board device mounted on a helicopter.

FIG. 2 is a block diagram of a configuration of an analytical plotting device deployed on the ground.

FIG. 3 is a block diagram showing a circuit configuration of an abnormality degree determination circuit 46 in FIG. 2;

FIG. 4 is a drawing example of a sudden wave detection result and each frequency component of a received radio wave.

FIG. 5 is a circuit block diagram of the sudden wave detection circuit 36.

6 is an analog signal waveform diagram at each processing stage in the sudden wave detection circuit 36. FIG.

7 is a frequency band of an output channel of the fast Fourier transform circuit 34. FIG.

FIG. 8 is a diagram of the maximum measured value of the defective / dirty insulator with respect to the healthy insulator in each channel.

FIG. 9 is a diagram of an evaluation value S1 of a defective / dirty insulator.

FIG. 10 is a field test result.

[Explanation of symbols]

10: Measurement Antenna 12: Radio Rangefinder 14: Ground Speed Meter 16: Position Fixed Marker 18: Interface Circuit 20: Data Recorder 22: Magnetic Tape 2
4: playback device 26: statistical processing circuit 28: voltage conversion circuit 30: distance correction circuit 32: buffer memory 3
4: Fast Fourier transform circuit (FFT) 36: Sudden wave detection circuit 38: Mark extraction circuit 42: Statistical processing circuit
44: Voltage conversion circuit 46: Abnormality determination circuit 48: Plotting device 49: Data recording device 50: Adder 52:
Division circuit 54: Exponentiation circuit 60: LPF 62: H
PF64: Peak detection circuit 66: Absolute value circuit 68:
Statistical processing circuit 70: Noise cut circuit 72: Absolute value circuit 74: Delay circuit 76: Sudden wave calculation circuit 78:
Fundamental wave height calculation circuit 80: output circuit 90: computer 92, 94, 96: amplifier 98: low-pass filter 100: pulse generation circuit 102: evaluation value calculation circuit

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Kazuo Yamagata 3-3-22 Nakanoshima, Kita-ku, Osaka Kansai Electric Power Co., Inc. (56) References JP-A-3-233374 (JP, A) JP-A Heisei 3-237372 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01R 31/12 G01R 31/08

Claims (18)

(57) [Claims] (1)Detect defective insulators from insulators holding transmission lines
Out of the way, Receive radio waves radiated from the transmission line and the insulator
Receiving step; Extracting a predetermined band component from the reception result of the receiving step
Extraction step; From the extraction result of the extraction step, the maximum value within a predetermined time
And a maximum average calculation step of detecting an average value, A sudden detection of a sudden wave from the reception result of the receiving step
A wave detection step; From the reception result of the receiving step, flow through the transmission line
The fundamental component of the current is extracted, and the
Basic peak value detection for detecting the peak value of the fundamental component
Steps and Maximum value and average calculated in the maximum average calculation step
Values, and are detected in the fundamental peak value detection step.
Determining a defective insulator from the peak value.
A method for detecting a defective insulator, comprising: 2. The method according to claim 1, wherein the determining step includes calculating the maximum average.
The difference between the maximum value and average value calculated in the step
Divide by the peak value detected in the main peak value detection step
2. The defective insulator according to claim 1, further comprising a dividing step.
Detection method. 3. The determining step further includes the dividing step.
The operation result of the tip is compared with the same division result for the sound insulator.
3. A defect insulator according to claim 2, comprising a comparing step of comparing.
How to detect children. 4. A similar division result for the sound insulator.
Calculates the difference between the maximum and average values for multiple insulators
This is the result of dividing by the peak value of the fundamental component at the time of detection.
The method for detecting a defective insulator according to claim 3. 5. The predetermined band component exceeds the fundamental component.
In the range of 1208 Hz or less,
The insulator according to any one of claims 1 to 4, wherein the insulator is a defective insulator.
How to detect a defective insulator. 6. The predetermined band component has a frequency of 1000 Hz.
The method for detecting a defective insulator according to claim 5, comprising: 7. The system according to claim 6, wherein the predetermined band component exceeds the fundamental wave component.
, Frequency 833Hz or less Included in the range below,
The child according to any one of claims 1 to 4, wherein the child is a fouling insulator.
Method of detecting defective insulators. 8. The method according to claim 1, wherein the predetermined band component has a frequency of 458 Hz or less.
And the defective insulator is a fouling insulator.
How to detect a defective insulator. 9. The method according to claim 1, wherein the predetermined band is a first band for the fouling insulator.
Band, and a second band for the defective insulator.
Determining the division step for the first band.
The division result of the second band is
Divided by the division result of the
The method for detecting a defective insulator according to claim 2, wherein the determination is made. 10. SendingDefect insulator from insulator holding wire
A device for detecting, Receive radio waves radiated from the transmission line and the insulator
Receiving means; Extraction for extracting a predetermined band component from the reception result of the receiving means.
Delivery means, From the extraction result of the extraction means, the maximum value within a predetermined time and
Maximum average calculating means for detecting an average value; Sudden wave detection for detecting a sudden wave from the reception result of the receiving means
Delivery means, From the reception result of the receiving means, the current flowing through the transmission line
Of the fundamental wave component of the
Fundamental peak value detecting means for detecting the peak value of the fundamental wave component
When, The maximum value and average value calculated by the maximum average calculation means,
And the wave height detected by the fundamental wave height detecting means.
Calculation means for calculating a judgment value of the defective insulator from the value
A defect insulator detecting device, characterized in that: 11. The computing means according to claim 1, wherein
The difference between the maximum value and the average value calculated in the step is
Division means for dividing by the peak value detected by the value detection means
The detecting device for a defective insulator according to claim 10, comprising: 12. The calculating means further comprises:
Compare the result of the operation with the same result of a division on a sound insulator
The detection of a defective insulator according to claim 11, further comprising a comparing unit.
apparatus. 13. A similar division result for the sound insulator.
Calculates the difference between the maximum and average values for multiple insulators
The result divided by the peak value of the fundamental wave component when detected In fruit
The defect insulator detection device according to claim 12. 14. The said predetermined band component is said fundamental wave component
Over the frequency range of 1208 Hz or less
14. The insulator according to claim 10, wherein the insulator is a defective insulator.
Item 2. The defect insulator detecting device according to the item 1. 15. The predetermined band component has a frequency of 1000H.
The apparatus for detecting a defective insulator according to claim 14, wherein z includes z. 16. The said predetermined band component is said fundamental wave component
Over the frequency range of 833Hz or less
14. The insulator according to claim 10, wherein the insulator is a fouling insulator.
2. A defect insulator detection device according to claim 1. 17. The predetermined band component has a frequency of 458 Hz.
The following is true, and the defective insulator is a fouling insulator.
2. A defect insulator detection device according to claim 1. 18. The method according to claim 18, wherein the predetermined band is a first band for the fouling insulator.
And a second band for the defective insulator,
Determining means for dividing the first band by the division means;
Dividing the calculation result by the division means with respect to the second band
A second dividing means for dividing the result by the result;
Output the result of the division by the
An apparatus for detecting a defective insulator according to claim 11.