CN110703051A - Precise positioning method for fault point of GIL (Gate in L) voltage withstand test based on acoustic wave detection method - Google Patents
Precise positioning method for fault point of GIL (Gate in L) voltage withstand test based on acoustic wave detection method Download PDFInfo
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- CN110703051A CN110703051A CN201910978958.0A CN201910978958A CN110703051A CN 110703051 A CN110703051 A CN 110703051A CN 201910978958 A CN201910978958 A CN 201910978958A CN 110703051 A CN110703051 A CN 110703051A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1209—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing using acoustic measurements
Abstract
The invention discloses a method for accurately positioning fault points of a GIL (general information language) withstand voltage test based on an acoustic detection method, which determines the installation number of decibel detectors; respectively numbering each decibel detector, and recording the decibel value of each decibel detector; presetting a decibel overflow value; when the GIL breaks down, recording the current time, acquiring all decibel values larger than a decibel overflow value and time nodes of the decibel values before and after the current time, drawing a circle by taking a decibel detector corresponding to the time node as a circle center and taking the propagation length corresponding to the time node as a radius, and displaying the intersection point of n circles on a GIL field arrangement diagram; and judging the most dense intersection point distribution area as a GIL fault point range. The invention has the beneficial effects that: in the GIL voltage withstand test process, if a fault occurs, the fault position can be quickly and accurately positioned, the test efficiency is improved, and a decision basis is provided for field test personnel.
Description
Technical Field
The invention relates to the field of ultra-high voltage and extra-high voltage power transmission and transformation equipment state monitoring, in particular to a precise positioning method for fault points of a GIL (gate in line) voltage withstand test based on an acoustic wave detection method.
Background
The actual operation working condition of simulation equipment that alternating current withstand voltage test can be comparatively close can discover the insulating defect or the condition of insulating degradation that equipment exists. Therefore, the alternating-current withstand voltage test has important significance for considering the insulation of the electrical equipment. This also makes the ac withstand voltage test an effective method for judging the insulation strength of electrical equipment.
However, in the current GIL voltage withstand test, the troubleshooting of fault points is still realized by installing a large number of GIL live monitoring probes and arranging a large number of guardians during the test. Generally, because sound propagation is scattered, when a fault occurs for the first time, the fault position of the GIL or the GIS cannot be judged specifically, repeated breakdown is carried out on tested equipment through multiple withstand voltage tests, the approximate range of the fault point can be judged effectively, and meanwhile, the fault position can be determined specifically after the tested GIL is subjected to specific exhaust exploration in the range.
Since the GIL withstand voltage test is a destructive test, the service life of the rest of the good tested products may be rapidly reduced by multiple withstand voltage tests. Meanwhile, the fault position cannot be judged quickly, so that time and labor are wasted in the fault point troubleshooting process, and great influence is generated on the whole power test period.
Disclosure of Invention
The invention aims to provide a method for accurately positioning fault points of a GIL (gate in line) voltage withstand test based on an acoustic detection method, aiming at inquiring the positions of the fault points as early as possible and improving the test efficiency.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a method for accurately positioning fault points of a GIL (gate in line) voltage withstand test based on an acoustic wave detection method,
determining the installation number of decibel detectors;
respectively numbering each decibel detector as a1, a2, a3 and a4 … … an, and recording decibel values of the decibel detectors;
presetting a decibel overflow value as K;
when the GIL fails, recording the current time as T;
collecting all decibel values larger than the K value and time nodes of the decibel values before and after time T, defining the time nodes as T1, T2, T3 and T4 … … tn, and redefining the positions of decibel detectors corresponding to the time nodes as f1, f2, f3 and f4 … … fn;
displaying a decibel detector position distribution diagram according to f1, f2, f3 and f4 … … fn, and synchronizing the decibel detector position distribution diagram to a GIL field layout diagram;
according to formula △ S-v △ T, △ T is | T-T1|, | T-T2|, | T-T3|, | T-T4| … … | T-tn |, v is the speed of sound in air, and △ S is calculated as d1, d2, d3 and d4 … … dn;
drawing circles by taking f1, f2, f3 and f4 … … fn as centers of circles and corresponding d1, d2, d3 and d4 … … dn as radii, wherein the intersection points of the n circles are defined as j1, j2, j3 and j4 … … jn, and the intersection points are displayed on a GIL field layout;
and judging the most dense intersection point distribution area as a GIL fault point range.
As an alternative embodiment, the installation number of the decibel detectors is determined according to the air chambers of the GIL, and one decibel detector is placed every two air chambers.
As an optional implementation manner, the value of the decibel overflow value K is determined according to a background decibel of a field test, and the value of the decibel overflow value K is 20dB higher than the background decibel.
As an alternative embodiment, said time T is acquired by a time grabber mounted on the outer wall of the GIL.
As an alternative embodiment, the decibel probe is mounted on the ground within 5m of the GIL.
As an optional implementation manner, the time T is within 5 seconds before and after the time T.
As an alternative, the position of the decibel detector is coordinate information.
As an optional implementation manner, the decibel detectors are connected to a background time synchronization system, and the decibel values of the decibel detectors are measured in real time.
As an alternative embodiment, the background time synchronization system is a synchronization clock.
As an alternative embodiment, the decibel detector is a distributed detector.
The invention has the beneficial effects that:
1. in the GIL withstand voltage test process, if a fault occurs, the fault position can be quickly and accurately positioned, the test efficiency is improved, and a decision basis is provided for field test personnel;
2. under the condition that the position of the fault point is difficult to judge, the method can effectively reduce the tested times of the intact equipment in the GIL;
3. the number of field guardians can be greatly reduced, and the test cost is reduced;
4. the device can be used in cooperation with an online monitoring probe, so that the fault point judgment precision is improved;
5. the number of the arranged decibel detectors can be effectively reduced, the field test rate is improved, and the test cost is reduced.
Drawings
FIG. 1 is a flow chart of a precise fault point positioning method for a GIL withstand voltage test based on an acoustic wave detection method;
fig. 2 is a schematic diagram of the principle of the embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the following detailed description of the present invention is provided with reference to the accompanying drawings and detailed description. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings.
As shown in fig. 1 and 2, the present embodiment provides a method for accurately positioning fault points in a GIL withstand voltage test based on an acoustic wave detection method, which is characterized in that:
100. determining the installation number of decibel detectors;
the installation number of the decibel detectors is determined according to the air chambers of the GIL, one decibel detector can be placed in every two air chambers, one decibel detector can also be placed in every two air chambers, the installation and placement number of the decibel detectors only influences the positioning precision, the greater the number, the higher the precision, the smaller the number, the lower the precision, and meanwhile, the installation intervals can not be completely consistent.
200. Respectively numbering each decibel detector as a1, a2, a3 and a4 … … an, recording decibel values of the decibel detectors, specifically, connecting the decibel detectors with a background time synchronization system, and measuring the decibel values of the decibel detectors in real time;
300. presetting a decibel overflow value as K;
400. when the GIL fails, recording the current time as T;
the phenomenon can take place to puncture in the twinkling of an eye before GIL breaks down, and the puncture can produce the loud sound, so at GIL outer wall installation time grabbing device, when the puncture takes place, the vibration conducts through the metal of GIL outer wall, when the vibration arrived time grabbing device, can trigger the time pause module in the device after the vibration amplitude surpassed the threshold value, and note current time be T, in addition, time T except can be by installing the time grabbing device collection income on the GIL outer wall, can also be other devices that can perception object vibration change and intercepting time point, more optimally, time grabbing device sets up in the middle part of GIL, avoids time T delay too much, leads to great error.
500. Collecting all decibel values larger than the K value and time nodes of the decibel values before and after time T, defining the time nodes as T1, T2, T3 and T4 … … tn, and redefining the positions of decibel detectors corresponding to the time nodes as f1, f2, f3 and f4 … … fn;
the number of the decibel detectors f1, f2, f3 and f4 … … fn corresponding to the time node is necessarily smaller than or equal to that of the decibel detectors a1, a2, a3 and a4 … … an, and because some decibel detectors are not selected because the distance and the received decibel are too small and are not larger than the K value, the positions of the collected decibel detectors are defined again, the decibel detectors which do not detect the sound wave and/or the received decibel detectors which do not exceed the K value are abandoned, and then the positions of the decibel detectors corresponding to the time node are f1, f2, f3 and f4 … … fn which are used as one of the background data of the system operation.
The time T is within 5 seconds before and after the time T, namely within +/-5 seconds of the T value, the optimal value is within 2 seconds before and after the time T, the T value is determined by conducting metal on the outer wall of the GIL and finally passing through a time grabbing device, the conducting speed of the metal reaches thousands of meters per second, the time grabbing device can acquire the T value at the moment that even the fast conducting speed cannot consider explosion, because the testing length of the GIL is usually several kilometers, if the explosion position is far away from the time grabbing device, an error is certainly generated, the direct embodiment is time T delay, if the common knowledge is used, only the sound wave after explosion is supposed to be acquired, relatively, some sound wave signals with the strongest decibel at the beginning of explosion are ignored due to the delay of the time T, and cannot be acquired. Because the time T is the key to start sound wave acquisition, a scheme of acquiring sound wave data before and after the time T is selected to avoid errors. The sampling frequency at time T is the same as the sampling frequency at other times in the present invention, and the sampling frequency is 50Hz or higher as at time nodes T1, T2, T3, and T4 … … tn described below.
600. The system background displays a decibel detector position distribution diagram according to f1, f2, f3 and f4 … … fn, and synchronizes to a GIL site layout diagram;
in this embodiment, the positions f1, f2, f3, and f4 … … fn of the decibel detector are calculated by a computer, a tablet computer, a mobile phone, a single chip microcomputer, or other devices with calculation capability, and certainly have data transmission capability, and the probe position distribution map obtained by the background calculation of the system can be synchronously transmitted to the GIL field layout map, so that a most intuitive schematic diagram is given to field test technicians, and a fault point can be quickly found. In addition, the GIL field layout is typically a handheld mobile terminal so that a technician at a field test can reach a trouble spot by holding the GIL field layout for troubleshooting.
700. According to formula △ S-v △ T, △ T is | T-T1|, | T-T2|, | T-T3|, | T-T4| … … | T-tn |, v is the speed of sound in air, and the travel time △ S is calculated as d1, d2, d3 and d4 … … dn;
as shown in fig. 2, 800, using f1, f2, f3 and f4 … … fn as the center, corresponding d1, d2, d3 and d4 … … dn as the radius to draw a circle, the intersection point of n circles is defined as j1, j2, j3 and j4 … … jn, and the intersection point is displayed on the GIL field layout diagram;
900. the most densely distributed intersection point region is judged as the GIL fault point range, and the points with scattered intersection points are judged as interference.
And the numerical value of the decibel overflow value K is determined according to the background decibel of a field test, and the numerical value of the decibel overflow value K is 20dB higher than the background decibel.
The decibel detector is mounted on the ground within 5m of the vicinity of the GIL.
The position of the decibel detector is coordinate information, the ground is taken as a plane, two vertical directions are taken as X, Y directions, meanwhile, the length proportion of the X, Y direction and the GIL must be input into a system background in advance, as the basis of operation, each decibel detector has a coordinate a1(x1, y1), a2(x2, y2), a3(x3, y3), a4(x4, y5) … … an (xn, yn), and f1, f2, f3 and f4 … … fn which are redefined after screening also have the same coordinate and are used as data of system background operation.
The decibel detector is a distributed detector, the background time synchronization system is a synchronous clock, the distributed detector and the synchronous clock can be purchased directly and are independent elements, complete equipment does not need to be generated, and the obtained data can be directly obtained through the formula of background operation. The sound wave is a continuous analog signal, and after the sound wave signal is collected by the decibel detector, discrete sampling with the same frequency is carried out on each time through a synchronization clock, and finally, each time required by the system background is adjusted to be synchronous.
Furthermore, the invention can be used with an on-line monitoring probe originally provided in the GIL, specifically, the on-line monitoring probe is firstly used for carrying out high-frequency detection on the interior of the GIL to roughly judge the position of a fault point, and then the sound wave of the invention is used for accurately positioning, so that the judgment precision of the fault point is improved.
As shown in fig. 2, the present invention specifically describes the above embodiment, assuming that a large sound occurs after the GIL test, the decibel detectors a1-a5 compare the collected decibels with the preset decibel overflow value K, record the time nodes of the decibel detectors greater than the value K, redefine the positions of the decibel detectors corresponding to the time nodes as f1-f4, calculate the distances d1-d4 from the moment when the large sound occurs to the sound waves received by each decibel detector according to the formula △ S-v- △ t, draw circles with the specific positions of f1-f4 as the centers, and use d 24-d 4 as the radii of f 5928-686f 9, as the four circles intersect to form intersection points j 2-j 12, as can be seen from the figure, the positions of j1-j4 are relatively dispersed, and the positions of j5-j9, j 10-12 are relatively concentrated, so that it can be determined that the number of the two or more concentrated regions of the fault detectors is not limited as the number of the above regions 12.
In the GIL withstand voltage test process, the method can quickly locate the fault position by adopting the principle that the sound wave detection ranges are crossed, can quickly and accurately locate the fault position, improves the test efficiency, provides decision basis for field test personnel, and can still effectively reduce the tested times of intact equipment in the GIL even if the collected intersection points are too scattered and the fault position is difficult to judge; the number of field guardians can be greatly reduced, and the test cost is reduced.
The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention accordingly, and not to limit the protection scope of the present invention accordingly. All equivalent changes or modifications made in accordance with the spirit of the present disclosure are intended to be covered by the scope of the present disclosure.
Claims (10)
1. A GIL withstand voltage test fault point accurate positioning method based on an acoustic wave detection method is characterized in that:
determining the installation number of decibel detectors;
respectively numbering each decibel detector as a1, a2, a3 and a4 … … an, and recording decibel values of the decibel detectors;
presetting a decibel overflow value as K;
when the GIL fails, recording the current time as T;
collecting all decibel values larger than the K value and time nodes of the decibel values before and after time T, defining the time nodes as T1, T2, T3 and T4 … … tn, and redefining the positions of decibel detectors corresponding to the time nodes as f1, f2, f3 and f4 … … fn;
displaying a decibel detector position distribution diagram according to f1, f2, f3 and f4 … … fn, and synchronizing the decibel detector position distribution diagram to a GIL field layout diagram;
according to formula △ S-v △ T, △ T is | T-T1|, | T-T2|, | T-T3|, | T-T4| … … | T-tn |, v is the speed of sound in air, and △ S is calculated as d1, d2, d3 and d4 … … dn;
drawing circles by taking f1, f2, f3 and f4 … … fn as centers of circles and corresponding d1, d2, d3 and d4 … … dn as radii, wherein the intersection points of the n circles are defined as j1, j2, j3 and j4 … … jn, and the intersection points are displayed on a GIL field layout;
and judging the most dense intersection point distribution area as a GIL fault point range.
2. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: the installation number of the decibel detectors is determined according to the air chambers of the GIL, and one decibel detector is arranged every two air chambers.
3. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: and the numerical value of the decibel overflow value K is determined according to the background decibel of a field test, and the numerical value of the decibel overflow value K is 20dB higher than the background decibel.
4. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: the time T is collected by a time grabber mounted on the outer wall of the GIL.
5. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: the decibel detector is mounted on the ground within 5m of the vicinity of the GIL.
6. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: and the time before and after the time T is within 5 seconds before and after the time T.
7. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: and the position of the decibel detector is coordinate information.
8. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: and the decibel detectors are connected with the background time synchronization system and measure the decibel value of each decibel detector in real time.
9. The method for accurately positioning the fault point of the GIL withstand voltage test based on the acoustic wave detection method according to claim 8, wherein: the background time synchronization system is a synchronization clock.
10. The method for accurately positioning fault points of the GIL withstand voltage test based on the acoustic wave detection method as claimed in claim 1, wherein: the decibel detector is a distributed detector.
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