CN1776437A - Method for measuring power cable equipment live or not - Google Patents
Method for measuring power cable equipment live or not Download PDFInfo
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- CN1776437A CN1776437A CN 200510048163 CN200510048163A CN1776437A CN 1776437 A CN1776437 A CN 1776437A CN 200510048163 CN200510048163 CN 200510048163 CN 200510048163 A CN200510048163 A CN 200510048163A CN 1776437 A CN1776437 A CN 1776437A
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Abstract
Using inductive probe collects signal of magnetic field generated by current of each phase in cable so as to form analog signal for representing consecutive change situation of magnetic field of each phase in power cable to be tested. A/D converted analog signal is stored. The signal is sent to subsequent processing, calculating, image displaying or drawing device so as to obtain consecutive curve of variation. Phase, amplitude of the said curve is compared with phase, amplitude of signal source in line frequency as well as of magnetic field of environmental setting. If phase relation of the curve is accorded with phase relation of signal source in line frequency, and amplitude of the curve is higher than signal amplitude of magnetic field of environmental setting, then the cable to be tested is determined in electrified state, using different phase relation, the invention distinguishes operating cable, warm standby cable and disused cable, not parallel in operation cable.
Description
Technical field
The invention belongs to fields of measurement, the correlation properties that relate in particular to a kind of field signal by measuring cable are judged the detection method that cable is whether charged.
Background technology
The cable machinery that is used for or once was used for electric power transfer or distribution is called power cable equipment (being called for short cable, down together).
Along with the progress of society and the development of industrial and agricultural production, especially the developing rapidly of nearly 20 years urban construction, the consumption of cable is increased sharply.A lot of cities have been defined in the inaccurate overhead transmission line that uses in urban district, large-arealy carried out, implemented " overhead transmission line is gone into ground " engineering (be about to transmission line of electricity or electric power networks that the reason overhead transmission line constitutes, substitute) by underground transmission circuit or the electric power networks that underground cable constituted.
Cable and pole line relatively have following advantage:
1. power supply quality is good, and the reliability height is not subject to the influence of surrounding environment and pollution.
2. insulation distance is little between line, takes up an area of few.
3. during underground laying, do not take up an area of face and space, both safe and reliable, attractive in appearance again.
Because the consumption of cable is increasing, and of the remote past, may repeatedly construct again, causes according to data to judge which bar cable is whether operation cable or discarded cable or cable in stock, equipment is in service, even cause construction to carry out.Therefore whether charged the site operation personnel need urgent a kind ofly can detect power cable, equipment method always.
At present, whether charged method mainly contains following several to detect power cable equipment:
1. listen electric current sound method: the method is the simplest, by the field signal around the coil detection streamer, by the amplification of signal, becomes voice signal output, judges according to the size of voice signal whether cable has a few.Because this method can't be got rid of the interference and the influence of electromagnetic signal in the environment in actual use, therefore only be applicable to the situation when early stage cable laying seldom.
2. external signal method:,, judge whether it is the cable of plus signal by trend and the path of detecting this signal by a certain cable applied the characteristic signal with certain electromagnetic signature.The method has avoided having or not the judgement of electricity, is significantly improved, and has improved the reliability of identification cable machinery.Now main popular this kind method.Whether the method no longer has been concerned about charged, gets final product but find out specific cable machinery.The method is complete at the cable laying construction information, situation clearly, can accurately judge the cable that applies signal.But,, can not use the method to detect for the situation that can't apply signal.
Open day is on March 23rd, 2005, publication number is to disclose a kind of " high pressure phase-splitting peak value point of contact electroscopy " in the Chinese invention patent application of CN1598599A, it utilizes in the triple-phase line, any phase line is when the positive-negative half-cycle peak value, at it vertically downward on the arbitrary measuring point beyond the safe distance, magnetic line of force tangent line and vertical plane are 30 ° ± 5 ° rule and measure, its measuring method is to be wound with the bar magnet of coil as detection means, place tested phase line vertically downward on the arbitrary measuring point beyond the safe distance, bar magnet overlaps with the magnetic line of force tangent line at this measuring point place, measure this phase line peak electricity magnetic signal, by changing bar magnet at the measurement direction at point position place or change its range finding, whether the peak electricity magnetic signal of judging this phase line according to the variation of bar magnet induced signal exists, and can judge whether this phase line is charged.
But, this method only is suitable for the whether charged judgement under the big situation of the physical separation of ultra-high-tension power transmission line or electric substation's mesohigh bus-bar three-phase conductors such as (being commonly called as busbar or copper bar), for cable, because its special structure (physical separation of three-phase heart yearn is very little), it uses testing result can only be similar to aforesaid tin of electric current sound method, still can't implement.
Simultaneously, because the induction current in cable, the equipment also is the AC signal and the harmonic signal thereof of sine (or cosine) ripple of 50HZ/60HZ, its high fdrequency component is abundant, so adopting said method can't distinguish the induced signal that exists on the cable machinery and hinder signal altogether, can not judge that it detects signal be by this cable itself charged magnetic field produced or produced by the magnetic field of induced electricity, lay under (as cable duct or cable testing bridge) situation wherein the electricity that whether has of a cable and judge so this technical scheme also can not be adapted to concentrate at many cables.
Summary of the invention
Whether charged technical matters to be solved by this invention provide a kind of testing power cable equipment detection method.It has introduced the phase relation of power frequency and harmonic wave thereof, by the comparison and the judgement of phase relation and amplitude, has solved the partition problem of stand-by heat cable and discarded cable and the cable that is not incorporated into the power networks, and makes judged result more accurate, has stopped the possibility of erroneous judgement; Simultaneously, owing to need not apply external signal, detection, more convenient to use, easy.
Whether charged technical scheme of the present invention is: provide a kind of testing power cable equipment detection method, it is characterized in that:
(1) with magnetic induction probe gather tested each phase current of power cable produce more than the field signal of a cycle, form a simulating signal of explaining the continuous situation of change in magnetic field of each phase of tested power cable;
(2) above-mentioned simulating signal is carried out the A/D conversion, form corresponding digital signal and storage;
(3) digital signal of above-mentioned storage is sent into follow-up processing, calculating, graphic presentation or drawing apparatus, show or draw out the continuous change curve of each phase field signal of tested cable respectively;
(4) phase relation of the three-phase field signal change curve of tested cable and the phase relation in power frequency component source are compared accordingly, simultaneously the amplitude of the three-phase field signal change curve of tested cable and the amplitude of environmental background field signal are compared accordingly;
(5) if the phase relation of the three-phase field signal change curve of tested cable meets the phase relation in power frequency component source, and its amplitude judges then that greater than the amplitude of environmental background field signal tested cable is in electriferous state;
(6) above-mentioned judged result being changed into discernible sound, light, numeral or waveform signal exports.
Concrete, its magnetic induction probe abuts against on the crust of tested cable and gathers the field signal that tested each phase of power cable is produced.
The phase relation in above-mentioned power frequency component source is that the phase differential of three-phase is 120 °.
Its described magnetic induction probe is the coil of hollow or ribbon core.
Further, above-mentioned magnetic induction probe quantity is one, this probe survey respectively tested each phase current of cable produce more than the field signal of cycle, form the simulating signal of the continuous situation of change in magnetic field of each phase of the tested power cable of a statement, carrying out the corresponding digital signal of A/D conversion back formation also stores, pass to respectively again and send into follow-up processing, calculating, graphic presentation or drawing apparatus, show or draw out the continuous change curve of each phase field signal of tested cable respectively.
Perhaps, above-mentioned magnetic induction probe quantity is three, the field signal of a cycle more than a certain phase current of the corresponding tested cable of detection of each probe produces, form the simulating signal of the continuous situation of change in magnetic field of each phase of the tested power cable of a statement, carrying out the corresponding digital signal of A/D conversion back formation also stores, pass to respectively again and send into follow-up processing, calculating, graphic presentation or drawing apparatus, show or draw out the continuous change curve of each phase field signal of tested cable respectively.
Above-mentioned a plurality of cycles are at least two complete cycles.
Compared with the prior art, advantage of the present invention is:
1. the method that adopts phase place, amplitude to compare simultaneously can distinguish operation cable, stand-by heat cable and discarded cable and the cable that is not incorporated into the power networks by the difference of phase relation;
2. owing to need not to apply external signal, detect more convenient to use, easy
3. on the basis of amplitude detection/judgement, introduce the phase relation of power frequency and harmonic wave thereof, made judged result more accurate, stopped the possibility of erroneous judgement.
Description of drawings
Fig. 1 is the process flow diagram of detection method of the present invention;
Fig. 2 is the field signal distribution schematic diagram that does not move cable and discarded cable;
The field signal distribution schematic diagram that Fig. 3 produces for the operation cable;
Fig. 4 is the functional circuit block scheme of the pick-up unit of employing the inventive method.
1 is cable among the figure, and 2 is cable core, and 3 for not moving the magnetic field magnetic line distributed architecture of cable and discarded cable, the 4 magnetic field magnetic line distributed architectures for operation or hot stand-by duty cable.
Embodiment
The present invention will be further described below in conjunction with accompanying drawing.
Among Fig. 1, detection method of the present invention is specific as follows:
(1) with magnetic induction probe gather tested each phase current of power cable produce more than the field signal of a cycle, form a simulating signal of explaining the continuous situation of change in magnetic field of each phase of tested power cable;
(2) above-mentioned simulating signal is carried out the A/D conversion, form corresponding digital signal and storage;
(3) digital signal of above-mentioned storage is sent into follow-up processing, calculating, graphic presentation or drawing apparatus, show or draw out the continuous change curve of each phase field signal of tested cable respectively;
(4) phase relation of the three-phase field signal change curve of tested cable and the phase relation in power frequency component source are compared accordingly, simultaneously the amplitude of the three-phase field signal change curve of tested cable and the amplitude of ambient signal are compared accordingly;
(5) if the phase relation of the three-phase field signal change curve of tested cable meets the phase relation in power frequency component source, and its amplitude judges then that greater than the amplitude of ambient signal tested cable is in electriferous state;
(6) above-mentioned judged result being changed into discernible sound, light, numeral or waveform signal exports.
Among Fig. 2, for not moving or discarded cable 1, have induced signal on the cable and hinder signal altogether, induction current in the heart yearn 2 all is the AC signal and the harmonic signal thereof of sine (or cosine) ripple of 50HZ/60HZ, high fdrequency component is abundant, the characteristics of its field signal that records 3 are that the phase place in three-phase magnetic field is identical, and the amplitude of its signal amplitude and environmental background field signal is approaching.
Among Fig. 3, for operation or hot stand-by duty cable, the electric current that passes through in its heart yearn 2 is a power current, and the phase differential of its three-phase current is 120 °, and the signal amplitude of the magnetic field magnetic line that its electric current produced is greater than the amplitude of environmental background field signal.
The present invention utilizes Fig. 2 and the phase place of Fig. 3 field signal distribution and the difference on the amplitude just, judges whether tested cable machinery is charged.
Among Fig. 4, the proving installation that is adopted should comprise detecting signal unit, A/D converting unit, signal memory cell, computing unit, waveform generation and display unit, waveform comparing unit and judged result output unit as shown in this figure at least.
For sensitivity and the stability that improves whole device, can also adopt functional circuits such as shaping, filtering, amplitude limit, amplification that signal is further processed.
Because the A/D conversion of above-mentioned magnetic induction input, simulating signal, storage, calculating, comparison, waveform show and functional circuits such as technology such as comparative result changes that discernible sound, light, numeral or waveform signal are exported into and shaping, filtering, amplitude limit, amplification are known technology, those skilled in the art can realize the present invention's embodiment fully after the detection of grasping the present invention, judgement principle, so its concrete circuit scheme and course of work is no longer narrated at this.
Embodiment 1:
The phase place angle that records the field signal of a certain cable three-phase in the cable duct is 120 °, and the amplitude of environmental background field signal is 5%, and the amplitude of cable three-phase field signal is 45%～55%, according to the principle of Fig. 3, so determine that it is the charging operation cable.
Herein field signal amplitude be through overtesting, the relative value that to set a certain induced voltage scope be standard (down with).
The generation reason of above-mentioned environmental background field signal: in cable duct, have many cables, these many cables all can produce magnetic field, at this moment the magnetic field that whole zone all can have the 50/60Hz electric current to produce, at this moment all magnetic field can be arranged in the whole cable duct regional space, so be referred to as the environmental background field signal.
In actual test process, need the magnetic induction probe is abutted against on the crust of tested cable, gather the field signal that tested each phase of power cable is produced.
Reliable, accurately for test result, 5 wave periods in test period location.
In above-mentioned test process, the magnetic induction sensor that uses commercially available various models all can, also can make by oneself hollow or have inductive coil unshakable in one's determination as magnetic induction sensor; The A/D of its detection signal conversion, store, calculate, show and adopt the 900X series power quality of going up sea cowry Chinese Electronics Co., Ltd. to finish that magnetic induction sensor is connected in the patchcord that primary current clamps and gets final product with the harmonic synthesis analyser.
Embodiment 2:
The phase place angle that records the field signal of a certain cable three-phase on the cable testing bridge is 120 °, and the amplitude of environmental background field signal is 20%, and the amplitude of cable three-phase field signal is 18%～22%, according to the principle of Fig. 3, so determine that it is the hot stand-by duty cable.
Adopt Goodwill MDS series digit storage oscilloscope or GOS series matching test oscillograph, magnetic induction sensor is connected on its signal input part and gets final product.
All the other are with embodiment 1.
Embodiment 3:
The phase place angle that records the field signal of a certain cable three-phase on the cable testing bridge is 0 °, the amplitude of environmental background field signal is 15%, the amplitude of cable three-phase field signal is near 15%, field signal is mainly high frequency, amplitude does not have obvious fluctuation, according to the principle of Fig. 2, so determine that it is non-live electric cable.
Adopt Beijing TDS30XXX of hyundai electronics Ltd series digit storage oscilloscope, magnetic induction sensor is connected on its signal input part and gets final product.
All the other are with embodiment 1.
Embodiment 4:
The phase place angle that records the field signal of a certain underground cable three-phase is 0 °, and the amplitude of environmental background field signal is 20%, and the amplitude of cable three-phase field signal is 20%, according to the principle of Fig. 2, so determine that it is discarded cable.
Adopting the patent No. is that disclosed three pincers figure phase voltammetric meters insert magnetic induction sensor at the former position that connects current clamp and get final product as graphics device in the Chinese utility model patent of ZL03272258.3.
All the other are with embodiment 1.
Embodiment 5:
The phase place angle that records the field signal of a certain underground cable three-phase is 120 °, and the amplitude of environmental background field signal is 20%, and the amplitude of cable three-phase field signal is 20%, according to the principle of Fig. 3, so determine that it is the cable that is not incorporated into the power networks.
All the other are with embodiment 1.
Because the method that the present invention adopts phase place, amplitude to compare simultaneously, can be by the difference of phase relation, distinguish stand-by heat cable and discarded cable and the cable that is not incorporated into the power networks, on the basis of amplitude detection/judgement, introduced the phase relation of power frequency and harmonic wave thereof, make judged result more accurate, stopped the possibility of erroneous judgement.Simultaneously, owing to need not to apply external signal, detect more convenient to use, easy.
The present invention can be widely used in the whether charged detection range of various power cable equipments.
Claims (7)
1. whether charged a testing power cable equipment detection method is characterized in that:
(1) with magnetic induction probe gather tested each phase current of power cable produce more than the field signal of a cycle, form a simulating signal of explaining the continuous situation of change in magnetic field of each phase of tested power cable;
(2) above-mentioned simulating signal is carried out the A/D conversion, form corresponding digital signal and storage;
(3) digital signal of above-mentioned storage is sent into follow-up processing, calculating, graphic presentation or drawing apparatus, show or draw out the continuous change curve of each phase field signal of tested cable respectively;
(4) phase relation of the three-phase field signal change curve of tested cable and the phase relation in power frequency component source are compared accordingly, simultaneously the amplitude of the three-phase field signal change curve of tested cable and the amplitude of environmental background field signal are compared accordingly;
(5) if the phase relation of the three-phase field signal change curve of tested cable meets the phase relation in power frequency component source, and its amplitude judges then that greater than the amplitude of environmental background field signal tested cable is in electriferous state;
(6) above-mentioned judged result being changed into discernible sound, light, numeral or waveform signal exports.
2. according to the whether charged detection method of the described testing power cable equipment of claim 1, it is characterized in that described magnetic induction probe abuts against on the crust of tested cable to gather the field signal that tested each phase of power cable is produced.
3. whether charged according to the described testing power cable equipment of claim 1 detection method, the phase relation that it is characterized in that described power frequency component source is that the phase differential of three-phase is 120 °.
4. according to the whether charged detection method of the described testing power cable equipment of claim 1, it is characterized in that the coil of described magnetic induction probe for hollow or ribbon core.
5. according to the whether charged detection method of the described testing power cable equipment of claim 1, it is characterized in that described magnetic induction probe quantity is one, this probe survey respectively tested each phase current of cable produce more than the field signal of cycle, form the simulating signal of the continuous situation of change in magnetic field of each phase of the tested power cable of a statement, carrying out the corresponding digital signal of A/D conversion back formation also stores, pass to respectively again and send into follow-up processing, calculate, graphic presentation or drawing apparatus show or draw out the continuous change curve of each phase field signal of tested cable respectively.
6. according to the whether charged detection method of the described testing power cable equipment of claim 1, it is characterized in that described magnetic induction probe quantity is three, the field signal of a cycle more than a certain phase current of the corresponding tested cable of detection of each probe produces, form the simulating signal of the continuous situation of change in magnetic field of each phase of the tested power cable of a statement, carrying out the corresponding digital signal of A/D conversion back formation also stores, pass to respectively again and send into follow-up processing, calculate, graphic presentation or drawing apparatus show or draw out the continuous change curve of each phase field signal of tested cable respectively.
7. according to the whether charged detection method of claim 1,5 or 6 described testing power cable equipment, it is characterized in that described a plurality of cycle is at least two complete cycles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100481638A CN100381826C (en) | 2005-12-06 | 2005-12-06 | Method for measuring power cable equipment live or not |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100481638A CN100381826C (en) | 2005-12-06 | 2005-12-06 | Method for measuring power cable equipment live or not |
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| Publication Number | Publication Date |
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| CN1776437A true CN1776437A (en) | 2006-05-24 |
| CN100381826C CN100381826C (en) | 2008-04-16 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNB2005100481638A Expired - Fee Related CN100381826C (en) | 2005-12-06 | 2005-12-06 | Method for measuring power cable equipment live or not |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103261918A (en) * | 2010-12-20 | 2013-08-21 | 罗伯特·博世有限公司 | Cable detector |
| CN104049137A (en) * | 2014-06-10 | 2014-09-17 | 国家电网公司 | Electricity measurement system for cable clamp |
| CN104332018A (en) * | 2014-08-13 | 2015-02-04 | 国家电网公司 | Magnetic-information feedback method used for cable terminal |
| CN113589022A (en) * | 2021-06-02 | 2021-11-02 | 台州宏创电力集团有限公司科技分公司 | Virtual robot-based live induction and alarm method for substation equipment |
| CN116953390A (en) * | 2023-07-01 | 2023-10-27 | 安徽博达项目管理咨询有限公司 | Data detection system for electromagnetic compatibility of optical cable pipeline |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86202436U (en) * | 1986-04-30 | 1987-09-16 | 辽宁省阜新矿务局高德煤矿营善队青年厂 | Miniature induction electrometrical instrument |
| CN1050199C (en) * | 1994-11-11 | 2000-03-08 | 韩佰锋 | Cable signal detecting and measuring apparatus |
| NO302915B1 (en) * | 1996-09-18 | 1998-05-04 | Alcatel Kabel Norge As | Cable test equipment |
| US6154447A (en) * | 1997-09-10 | 2000-11-28 | At&T Corp. | Methods and apparatus for detecting and locating cable failure in communication systems |
| CN2364470Y (en) * | 1999-02-10 | 2000-02-16 | 福州新纪高压电器有限公司 | Cable connector type voltage indicating device |
| CN2522864Y (en) * | 2001-09-12 | 2002-11-27 | 杨汝达 | Induction-type high-voltage charge displaying device for cable |
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2005
- 2005-12-06 CN CNB2005100481638A patent/CN100381826C/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103261918A (en) * | 2010-12-20 | 2013-08-21 | 罗伯特·博世有限公司 | Cable detector |
| CN103261918B (en) * | 2010-12-20 | 2016-02-03 | 罗伯特·博世有限公司 | Line probers |
| US9372217B2 (en) | 2010-12-20 | 2016-06-21 | Robert Bosch Gmbh | Cable detector |
| CN104049137A (en) * | 2014-06-10 | 2014-09-17 | 国家电网公司 | Electricity measurement system for cable clamp |
| CN104332018A (en) * | 2014-08-13 | 2015-02-04 | 国家电网公司 | Magnetic-information feedback method used for cable terminal |
| CN113589022A (en) * | 2021-06-02 | 2021-11-02 | 台州宏创电力集团有限公司科技分公司 | Virtual robot-based live induction and alarm method for substation equipment |
| CN113589022B (en) * | 2021-06-02 | 2023-09-29 | 台州宏创电力集团有限公司科技分公司 | Substation equipment live induction and alarm method based on virtual robot |
| CN116953390A (en) * | 2023-07-01 | 2023-10-27 | 安徽博达项目管理咨询有限公司 | Data detection system for electromagnetic compatibility of optical cable pipeline |
| CN116953390B (en) * | 2023-07-01 | 2024-04-05 | 安徽博达项目管理咨询有限公司 | Data detection system for electromagnetic compatibility of optical cable pipeline |
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| CN100381826C (en) | 2008-04-16 |
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