KR101065910B1 - How to check power equipment - Google Patents

Abstract

The present invention relates to the detection of bad power equipment installed in a power distribution line in operation, and detects ultrasonic signals emitted from a power equipment in which instantaneous high frequency noise is measured in a power distribution equipment at a long distance to safely operate a facility without approaching dangerous high voltages. The present invention relates to a method for inspecting power equipment that can be detected. In accordance with an aspect of the present invention, there is provided a method for checking a power equipment, comprising: detecting a high frequency noise signal emitted from a power equipment of the power distribution line while instantaneously along a power distribution line; Collecting an ultrasonic signal from the power equipment in which the high frequency noise signal is detected; Receiving the collected ultrasonic signals and converting the received ultrasonic signals into acoustic signals; And extracting only a signal having a power frequency and a multiple of the frequency components from the converted sound signal to detect the sound signal due to the ultrasonic signal emitted from the faulty equipment of the power equipment in the presence of external noise. It includes.

Description

{Method for checking Power Utilities}

The present invention relates to the inspection of bad power equipment installed in a power distribution line in operation, and detects ultrasonic signals emitted from a power equipment in which instantaneous high frequency noise is measured in a power distribution facility at a long distance, thereby safely operating a facility without approaching dangerous high voltages. The present invention relates to a method of inspecting power equipment that can be checked.

Regarding the method and apparatus for instantaneously checking and inspecting the defective facilities of distribution lines scattered throughout the country without going to Jeonju by vehicle or on foot, the present applicant has registered Korean Patent No. 10-0795190 And method) and Republic of Korea Patent No. 10-0915633 (a device and method for detecting defective equipment for overhead distribution line by comparing the amount of change in the high frequency noise signal).

In order to check (detect) the faulty equipment on the distribution line, move by car or on foot and continuously receive high frequency noise and analyze it. When a bad signal is detected, it is checked by using a directional antenna to get out of the car and verify it. have.

Apart from this, the vehicle is driven along the distribution line at a low speed to detect an ultrasonic signal and detect a defective facility.

Ultrasound is a sonic signal at a frequency higher than 20 kHz, the upper limit of human audible frequency, and typically reaches within 15 meters of the air. Unlike radio waves, ultrasonic signals are the vibrational energy of sound waves, so they are used for inspection of power distribution facilities by taking advantage of the shorter reach and finding the correct sound source.

However, the place where instantaneous inspection and inspection of power distribution facilities is not an enclosed interior, but the outdoor area, and the ultrasonic signal generated from the power facilities is almost negligible compared to the ambient noise such as wind and vehicle.

The American Society for Testing and Materials (ASTM) issued an ultrasonic leak measurement standard (E1002) that defines the method of detecting ultrasonic signals emitted from the air at a long distance.It is produced when the compressed nitrogen gas is discharged through a 0.2mm nozzle. It is defined that an ultrasonic signal should be able to be detected at a distance of 10m.

Conventional ultrasonic inspection equipment produced on this basis can measure a small amount of gas leakage noise in a quiet environment at a distance of 10m, but it is not covered by bad noise by surrounding noises such as wind and vehicle driving sounds outdoors in the actual power equipment inspection place. It is almost impossible to detect the generated ultrasonic signal.

Dish-type (parabola) acquisition antenna is used to collect ultrasonic signals effectively, but the antenna opening is wide and antenna gain is large, and external noise signals such as wind are also collected. In order to improve this, a conical antenna with a narrow opening surface has been proposed, but it is made of an opaque material so that the maximum signal point can be detected by comparing and moving along the overall outline of the target, but the object is hidden by the field of view of the ultrasonic collection antenna. There is discomfort. In addition, because the power distribution equipment is installed along the road, the inspector cannot grasp the traffic flow, which is dangerous.

The present invention is to solve the above problems, to provide a power equipment inspection method and apparatus that can be checked even in the presence of external noise by extracting and analyzing only the signal related to the power frequency in order to enable ultrasonic inspection of the power equipment outdoors. There is a purpose.

An object of the present invention is to provide a power equipment inspection method for detecting high frequency noise at a line instantaneously and detecting an ultrasonic signal at a place where high frequency noise is detected in order to improve efficiency of instantaneous power distribution facilities. .

The present invention uses a conical ultrasonic signal collection antenna made of a transparent material that minimizes the influence of external noise and simultaneously detects the contour of a target when detecting an ultrasonic signal emitted from a power facility outdoors. The purpose is to provide a method.

An apparatus for executing a power equipment inspection method according to the present invention includes an ultrasonic signal processing apparatus and an antenna.
The ultrasonic signal processing apparatus receives an ultrasonic signal emitted from a power facility installed outdoors, converts the received ultrasonic signal into an acoustic signal, and includes only a signal having a power frequency and a multiple frequency component among the converted acoustic signals. Extraction, and the defective part of the said power equipment is grasped | ascertained by detecting the said acoustic signal resulting from the said ultrasonic signal emitted from the defective point of the said power equipment in the presence of external noise.
The ultrasonic signal processing apparatus demodulates the ultrasonic signal converted into an electrical signal into an audio signal which is an audible frequency, and then Fourier transforms or filters and extracts only the fundamental and harmonic components of a power frequency (60 Hz, 50 Hz in some countries) and sums them. To be processed.
The antenna is made of a conical transparent material having a narrow opening surface, and collects the ultrasonic signals emitted from the power equipment and transmits the ultrasonic signals to the ultrasonic signal processing apparatus.
In order to minimize the influence of external noise, the conical antenna has a viewable material having a structure that keeps the maximum aperture diameter within a certain size and easily grasps the outline and traffic flow of the target to be checked.
Preferably, the ultrasonic signal processing apparatus demodulates the ultrasonic signal converted into an electrical signal without an intermediate frequency, and limits the demodulated sound signal to a band below a predetermined frequency and processes the same.
In accordance with an embodiment of the present invention, a method for checking a power equipment includes detecting a high frequency noise signal emitted from a power equipment of the power distribution line while instantaneously along a power distribution line, and collecting an ultrasonic signal from the power equipment where the high frequency noise signal is detected. Receiving the collected ultrasonic signals and converting the received ultrasonic signals into acoustic signals; and extracting only signals having a power frequency and multiples of the frequency components from the converted acoustic signals, in the presence of external noise. Detecting the acoustic signal attributable to the ultrasonic signal emitted from the defective equipment of the apparatus.
Preferably, the power equipment inspection method according to the present invention, when detecting the defective equipment by collecting the ultrasonic signal emitted from the power equipment, scanning according to the shape of the power equipment, by adjusting the gain (gain) by The maximum signal point is detected, and at various angles not in one direction, various frequency signals other than one acoustic frequency are compared to detect the defective equipment that is the source of the ultrasonic signal.
Preferably, in the power equipment, when the high frequency noise signal is detected but the ultrasonic signal is not detected, it is determined that there is a defect inside the power equipment.

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Such a power equipment inspection method and apparatus according to the present invention has the following effects.

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First, it is possible to measure the ultrasonic signal emitted from the poor power equipment even in the environment where there is ambient noise in the outdoors, so that accurate facility inspection is possible.
Secondly, it is possible to make efficient distribution line instantaneous by measuring the ultrasonic signal to the power equipment where the high frequency noise signal is detected.

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Third, it has a transparent structure that can grasp the outline of the target to be inspected and the traffic environment of the measuring place, so that it is possible to inspect the power equipment quickly and safely.

1 is an internal configuration diagram of a conventional power equipment inspection device,
2 is an exemplary apparatus diagram for executing a power equipment inspection method according to the present invention;
3 is a block diagram of a data storage device of an apparatus for executing a power equipment checking method according to the present invention;
4 is a peripheral noise ultrasound signal Fourier transform analysis screen,
5 is a failure facility ultrasonic signal Fourier transform analysis screen,
6 is a signal comparison screen of FIGS. 4 and 5;
7 is a Fourier analysis screen after signal processing according to the present invention,
8 is a signal value fluctuation scope screen when detecting a failure facility in accordance with the present invention,
9 is a scope screen for continuously detecting defective equipment according to the present invention,
10 is a view of a main device in an apparatus for executing a power equipment inspection method according to the present invention;
11 is a front view of the main apparatus in the apparatus for executing the power equipment checking method according to the present invention;
12 is a side view of the main device in the apparatus for executing the power equipment inspection method according to the present invention;
13 is a view of the connection between the main device and the data storage device in the apparatus for executing the power equipment inspection method according to the present invention,
14 is a screen view of a data storage device in the device for executing the power equipment inspection method according to the present invention,
15 is a state of checking the power equipment by the power equipment check method according to the present invention in the state of getting off,
16 is a state of checking the power equipment by the power equipment check method according to the invention in the state of riding,
17 is a check procedure (detection procedure) according to the power equipment inspection method according to the present invention,
18 is a check procedure (undetected procedure) according to the power equipment inspection method according to the present invention,
19 is a data storage procedure in the power equipment inspection method according to the present invention.

Hereinafter, a method for checking power equipment according to the present invention will be described in detail.

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An effective distribution line instantaneous method is to use an ultrasonic signal processing device (ultrasound detector) that can detect a high frequency noise signal with a fast inspection speed, and can effectively detect an ultrasonic signal emitted from a power facility in a place where a high frequency noise signal is detected. .

However, as described in the background art, general ultrasonic measurement equipment is optimized to hear mechanical leakage, leakage, friction noise, etc., rather than for power equipment inspection, so it is impossible to make accurate measurements outdoors. Find and detect faulty equipment.

In the place where the bad line post insulator is installed on the pole, in the windless weather, the ambient noise is measured as shown in FIG. 4. In other words, the frequency distribution details of the Fourier transform are obtained by demodulating the ultrasonic signal flowing into the atmosphere without targeting the target and limiting it to an acoustic signal of 1000 Hz or less again. The absolute dB values shown in the graph are evenly distributed from -20 dB to -40 dB. In addition, particularly large signals are not detected at power and harmonic frequencies.

5 is a value measured by aiming the bad line post insulator from the ground. Although there is no significant difference from FIG. 4, in detail, it can be found that signals of the second harmonic (120 Hz) and the fourth harmonic (240 Hz) of the power frequency are increased compared to other values.

6 is a graph comparing FIG. 4 and FIG. 5. When FIG. 4 is viewed as a background noise in which an ultrasonic signal is not detected and FIG. 5 is detected as noise, it is difficult to detect this as a variation value of the entire signal level of the acoustic signal. Rather, the sum of the total signals may be less than that of FIG. Due to this phenomenon, a general ultrasonic checker is a structure that cannot detect a minute ultrasonic signal generated from an outdoor power installation.

1 is an internal configuration diagram of a conventional ultrasonic inspection apparatus.

The ultrasonic vibration energy introduced into the ultrasonic antenna 101 is converted into a high frequency electric signal of 40 kHz center frequency and supplied to the mixers 105 and 107 which are converted into an audible frequency of 2 kHz through the filters 102, 104 and the amplifier 103, and then through the amplifiers 109 and 110. Use heterodyne receiver circuit that outputs meter value and speaker.

As described in the background art, the use of such a complex heterodyne receiver circuit is the main user of the conventional ultrasonic checker, and mechanical (bearing) friction noise, gas leakage noise, etc. do not generate a signal at a certain frequency. Because it occurs at an arbitrary frequency, to detect this, it is necessary to monitor the entire frequency band of the sound and observe the minute change.

On the other hand, the acoustic signal of the ultrasonic signal generated in the power equipment has a characteristic that appears only in the power frequency (60Hz, some countries 50Hz) and the harmonic frequency band that is a multiple thereof as shown in FIG.

If you ignore the characteristics of the ultrasonic signal generated in the power equipment and detect the power equipment without separating it from the outdoor broadband ambient noise signal, it becomes difficult to detect it efficiently.

Accordingly, the configuration of the apparatus for implementing the power equipment inspection method according to the present invention is as follows.

Apparatus to which the power equipment checking method according to the present invention shown in FIG. 2 is applied includes a main device 10 and a data storage device 20. First, the ultrasonic collection antenna 201 of the main apparatus 10 is an antenna structure using a transparent material having a conical structure with a reduced opening diameter, and ultrasonic vibration energy introduced through the antenna inlet converges around the membrane of the lower ultrasonic sensor. And converted into an electrical signal. The weak electrical signal is improved and amplified by a low pass filter 202, an RF amplification 203, a low noise amplification 204, and a band pass filter. The amplified signal is converted into an acoustic signal using a single frequency demodulator that does not use intermediate frequencies such as heterodyne.

Since the acoustic frequency generated at the location of power equipment failure is limited to multiples of the power frequency (50Hz, 60Hz), the signal processing unit 208 passes only 800Hz or less, which is a part of the overall acoustic frequency, and the basic power frequency and 2, 3 included in this. Extract the sum of 4, 5 times frequencies.

The sum of the total power values below the acoustic frequency of 800 Hz and up to five times the power frequency is added to generate an alarm when the ratio between the two is greater than or equal to a predetermined ratio, so that the selected 210 audio signal can be heard through the speaker 211.

It also converts the analog signal to digital (209) so that the magnitude of the signal can be compared and displays the magnitude of the selected value (214) with the LED BAR 212.

The structure of the data storage device 20 of FIG. 3 receives the measured value through serial communication (305), displays the value as a numerical value on the LCD as shown in FIG. 14, and also receives an alarm generated by the signal processor (304). ) To handle the alarm. On the other hand, a command for selecting a gain adjustment and a filter is sent to the main device, and the result thereof is displayed as shown in the lower part of FIG.

In addition, when the storage function is selected, the audio signal input through the Audio In Jack is converted to digital (301) and stored in a buffer, and when a predetermined size or more is stored in the WAND file in the NAND FLASH memory through DMA. This stored sound file can be recalled to perform functions such as sound reproduction, FFT analysis and waveform analysis.

7 is a Fourier analysis screen in which signals of 120 Hz and 360 Hz are detected after signal processing. In this way, if the unnecessary signal is removed and only the drain signal of the power frequency is extracted and measured, only the ultrasonic signal emitted from the power equipment can be detected more effectively.

8 is a screen of measuring a signal change that appears when the power equipment inspection apparatus to which the present invention is applied is aimed at a power equipment that generates a bad signal. The ultrasonic RF signal 403 and the demodulated sound wave 401 remain unchanged while the signaled output 402 can observe the signal fluctuation reliably.

9 is a scope measurement screen showing that a signal is detected regardless of fluctuations in ambient noise. That is, even if the RF signal 406 and the entire sound signal 404 fluctuate with the surrounding noise, the signal-processed output 405 maintains a value, and thus it can be seen that a signal having a predetermined value or more can be detected even in external noise. Can be.

10 and 11 are photographs showing the front panel of the main unit. Turn on the power switch 216 and select 214 the signal to be displayed in the signal LEVEL BAR 212. In other words, the F1 selection is a 60Hz frequency acoustic signal, the F2 selection is 120, 180, 240, 300Hz sum acoustic signal, T can be selected and compared the entire acoustic signal of less than 800Hz. If the ratio between the sum of the power frequency signal and the total value below 800Hz is over a certain level, the Signal (213) Lamp is turned on. If the battery is under voltage, the Low / Batt Lamp (215) is turned on.

Figure 12 shows the left side of the main unit with the speaker 211 output selection 215 switch. The switch positions are T and F, where F is the sum of power frequency multiples and T is the total sound signal below 800 Hz.

The gain adjusting volume 217 adjusts the gain of the RF signal so that the user can detect the maximum point of sound while scanning along the shape of the power equipment.

13 is a view connected between the main device and the storage device. RS232 and Audio are connected

14 is an LCD display portion of the data storage device 20. It displays and adjusts the ultrasonic signal level, gain (GN), center frequency (CF), automatic gain control (AG), alarm level (TV), and peak value (PK).

15 and 16 are photographs taken in the actual field measurement. FIG. 15 illustrates a case where the vehicle is measured by getting off the vehicle, and FIG. 16 illustrates a case where the vehicle is measured in the vehicle. Since most distribution lines are installed along roads, conical antennas are used to reduce the effects of wind and vehicle noise, and transparent see-through antennas are used to easily identify the shape of targets, and traffic flows along the road. It is easy to grasp and considers the convenience and safety of the operator.

According to the power equipment inspection method according to the present invention, it is possible to check the power equipment installed in the outdoors, and move along the distribution line, and when the power equipment is instantaneously, the high frequency noise signal free from the wind effect and tire noise caused by the vehicle movement is detected. It will be a more efficient line instantaneous method to detect the defective equipment by first detecting and measuring the ultrasonic signal to the power equipment installed in the place where the high frequency noise signal is detected.

Figure 17 illustrates the procedure of applying the power equipment inspection method according to the invention in the field. First, while checking the presence or absence of a signal through the high frequency noise receiver while navigating along the distribution line (501), if a high frequency noise signal is detected (502), after the vehicle is stopped, the ultrasonic inspection is started using the ultrasonic detection apparatus (503).

First set the speaker selection switch 215 to the F position, set the gain volume 217 to the maximum value, set the LED display selection 214 to F2 (504), aim the power equipment (216) and sequentially follow the shape. When a signal is detected (505) (506), the gain volume is lowered (507) and compared to detect the maximum signal generation point (508).

To verify this, scan to see if it is the maximum point due to reflection (510) and change the direction (509) and show the maximum point (510) regardless of the direction and recognize it as the maximum point and the same at other frequencies (F1, T) Verify that the value is represented (511).

If all of the above items match, the ultrasonic signal source detection is completed (512).

Fig. 18 is a procedure for the case where an ultrasonic signal is not detected when a defect occurs in a facility or a closed part even if a high frequency noise signal is detected. That is, if a high frequency noise is detected but no ultrasonic signal is detected (506), it is checked whether there is a noise source other than the electric company in the vicinity (513). If noise occurs in a facility other than the distribution facility in the surrounding area (514), it ignores and continues the instantaneous distribution line (515). However, if there is no other noise source in the vicinity, if the high frequency noise is measured once again using a directional antenna or the like (516) and continuously detected (517), it is determined that the internal failure of the power equipment (518). The reason for the internal failure is that the ultrasonic signal can be detected only when the field of view is secured, while the ultrasonic wave is not detected because the high frequency noise is relatively less affected by the obstacle between the signal source and the ultrasonic inspection device. If high-frequency noise occurs continuously, it can be determined that it occurs in a hidden place that is not visible to the operator or the naked eye.

19, when the ultrasonic signal source is detected (512), the data storage device is connected to store the data (519) and the aim of the ultrasonic signal source (520) is displayed more numerically on the LCD than the LED BAR of the main unit. Check whether the maximum point matches the value (521) and store the signal (522). If the maximum point does not match (521), measure again. (507)

Claims (7)

delete delete delete delete Detecting a high frequency noise signal emitted from a power facility of the distribution line while traveling along a distribution line;
Collecting an ultrasonic signal from the power equipment in which the high frequency noise signal is detected;
Receiving the collected ultrasonic signals and converting the received ultrasonic signals into acoustic signals; And
Extracting only a signal having a power frequency and a multiple of the frequency components from the converted sound signal to detect the sound signal due to the ultrasonic signal emitted from the defective equipment of the power equipment in the presence of external noise;
Power equipment check method for grasping the defective point of the power equipment, characterized in that it comprises a. 6. The method of claim 5,
When collecting the ultrasonic signal emitted from the power equipment to detect the defective equipment, scan along the shape of the power equipment, adjust the gain to detect the maximum signal point, one from several angles, not one Comparing various frequency signals other than the acoustic frequency of the, characterized in that for detecting the defective equipment that is the source of the ultrasonic signal, power equipment inspection method. delete

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