CN102305901A - Method for detecting cable fault point by impact oscillating wave principle - Google Patents
Method for detecting cable fault point by impact oscillating wave principle Download PDFInfo
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- CN102305901A CN102305901A CN201110149078A CN201110149078A CN102305901A CN 102305901 A CN102305901 A CN 102305901A CN 201110149078 A CN201110149078 A CN 201110149078A CN 201110149078 A CN201110149078 A CN 201110149078A CN 102305901 A CN102305901 A CN 102305901A
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- cable
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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
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/11—Locating faults in cables, transmission lines, or networks using pulse reflection methods
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Abstract
The invention discloses a method for detecting a cable fault point by an impact oscillating wave principle. The method comprises the following steps: the grounding output end of a pulse signal source is connected with the initial end grounding line of a fault cable to be detected; the high-voltage output end of a signal source is connected with one end of a high-voltage resonance reactor; the other end of the reactor is connected with a fault phase; the terminal end groundling line is cut off; the signal source applies the pulse signal by the reactor so that the fault point forms an instant short circuit electric arc; the fault cable generates a damped oscillating wave and radiates an electromagnetic field signal to the outside; the magnetic field signal in the signal is detected; a damped oscillating wave form for reflecting magnetic field signal change is arranged at the left side in the front of the cable fault point; a damped oscillating wave form for reflecting sharp attenuation of the magnetic field signal change is arranged at the right side behind the cable fault point; and the cable position corresponding to the change place of the magnetic field signal is the position in which the cable fault point is located. The invention is suitable for cable fault positioning under various laying conditions, has the advantages of simple structure and convenience in use and is widely used for power systems and all enterprises and public institutions.
Description
Technical field
The present invention relates to a kind of cable fault localization method, being specifically related to is a kind of method with shock oscillation ripple principle detection streamer trouble spot.
Background technology
Urbanization is fast-developing; For the needs of beautifying the environment with national defence; Change built on stilts in a large number power circuit into buried cable; The use amount of cable is increased sharply; And take place owing to frequent reasons such as municipal construction have caused a large amount of cable faults; In order to find the underground cable trouble spot rapidly and accurately, become the difficult problem that the cable repairing recovers to send electricity.Especially in the face of increasing branch cable, poling cable, how many traditional detection cable fault point methods exists certain defective, and main method has at present:
1, traditional sound detection, and sound, the magnetic-synchro sound detection of subsequent improved, sound, magnetic time difference method,, magnetic wave shape time difference method all is difficult to effective operate as normal owing to being subject to locate the live audio noise.
2, step voltage method is used the fault that only can adapt to few part at the scene owing to can only be used for the location of direct-buried cable earth fault, is mainly used in the location of direct-burried extra-high-tension cable metallic jacket earth fault at present.
3, frequency induction method can only be used for special metallic short circuit and open fault location, and this fault only belongs to special case in a large amount of cable faults that take place.
4, steel armour current field probe method has disclosed patent, but only theoretical feasible, is subjected to the cable scene to lay the restriction of situation and impracticable, and its applying unit will remove from the propaganda webpage of company by the product of its principle development.
5, Low Voltage Impulse Method, high voltage pulse method (flashover method), second pulse method, multiple pulses method, they all only can be used for the pre-determined bit of cable fault, but not accurately locate.
Summary of the invention
The purpose of this invention is to provide a kind of method that a kind of insulation fault of main push-towing rope and branch cable of the cable that can lay poling, direct-burried, raceway groove, tunnel carries out localization of fault with shock oscillation ripple principle detection streamer trouble spot.
In order to overcome the deficiency of prior art, technical scheme of the present invention is to solve like this: a kind of special character of the method with shock oscillation ripple detection streamer trouble spot is to be undertaken by following step:
1), the ground connection output terminal of common impacting with high pressure pulse signal source is connected to the top ground wire of failure cable to be measured;
2), the high-voltage output end of common impacting with high pressure pulse signal source connects an end of high pressure resonance reactor;
3), the other end of high pressure resonance reactor is connected to the fault phase of failure cable to be measured;
4), the terminal ground wire with failure cable to be measured breaks off;
5), common impacting with high pressure pulse signal source applies the impacting with high pressure pulse signal for failure cable to be measured through the high pressure resonance reactor, makes the trouble spot form instantaneous short circuit electric arc;
6), on failure cable, produce damp oscillatory wave along failure cable transmission and outside radiation field signal;
7), field signal pick-up unit and field signal induction receiving coil is connected, field signal induction receiving coil is along the variation of failure cable detection field signal;
8), the damped oscillation waveform that has a reflection field signal to change of the left side before the Method of Cable Trouble Point, this damped oscillation waveform is presented on the display unit of field signal pick-up unit;
9), the right side after Method of Cable Trouble Point, then be the damped oscillation waveform of the rapid decay that changes of magnetic reaction fields signal, this sharply damped oscillation waveform of decay be presented on the display unit of field signal pick-up unit;
10), from the forward and backward wave form varies of Method of Cable Trouble Point position also with regard to the trouble spot institute occurrence positions of corresponding failure cable to be measured, promptly pairing cable position is exactly the position at Method of Cable Trouble Point place to field signal from having to unconverted place.
The present invention compared with prior art, advantage of the present invention is:
1, shock oscillation ripple cable fault localization method can differentiate rapidly that the trouble spot occurs in that branch in the multi-way cable;
2, the cable fault that adapts under poling, direct-burried, raceway groove, the various cable laying situations in tunnel is located;
3, thoroughly be not subjected to the influence of localization of fault live audio noise during localization of fault, judge directly perceived simple;
4, can look into the cable trace trend by the limit gulde edge, this device is dual-use.
Simple in structure, easy to use, be widely used in electric system, each enterprises and institutions.
Description of drawings
Fig. 1 is a localization method application structure schematic block diagram of the present invention;
Fig. 2 is field signal induction receiving coil and the failure cable synoptic diagram of Fig. 1;
Fig. 3 is detected damped oscillation squiggle figure before the trouble spot that shows of the field signal pick-up unit of Fig. 1;
Fig. 4 is the damped oscillation squiggle figure of detected rapid decay behind the trouble spot that shows of the field signal pick-up unit of Fig. 1.
Among the figure, 1 is common impacting with high pressure pulse signal source, and 1a is its high-voltage output end, and 1b is its ground connection output terminal; The 2nd, the high pressure resonance reactor, 2 and 1 has formed impacting with high pressure pulse signal source of the present invention jointly; The 3rd, failure cable to be measured; The 4th, failure cable to be measured top ground wire; The 5th, the trouble spot; The 6th, failure cable to be measured terminal ground wire; The 7th, failure cable fault phase to be measured; The 8th, the field signal pick-up unit; The 9th, the waveform display unit of field signal pick-up unit 8; The 10th, the field signal induction receiving coil of field signal pick-up unit 8; The 11st, the detection waveform of field signal pick-up unit 8 before the trouble spot; The 12nd, the detection waveform of field signal pick-up unit 8 behind the trouble spot; The 13rd, the field signal signal ripple before the trouble spot 5.
Embodiment
Below in conjunction with accompanying drawing content of the present invention is described further.
Embodiment 1
With reference to shown in Figure 1, a kind of localization method with shock oscillation ripple detection streamer trouble spot, undertaken by following step:
1), the ground connection output terminal 1b of common impacting with high pressure pulse signal source 1 is connected to the top ground wire 4 of failure cable 3 to be measured;
2), the high-voltage output end 1a of common impacting with high pressure pulse signal source 1 connects an end of high pressure resonance reactor 2;
3), the other end of high pressure resonance reactor 2 is connected to the fault phase 7 of failure cable to be measured;
4), the terminal ground wire 6 with failure cable 3 to be measured breaks off;
5), common impacting with high pressure pulse signal source 1 applies the impacting with high pressure pulse signal for failure cable 3 to be measured through high pressure resonance reactor 2, makes trouble spot 5 form the instantaneous short circuit electric arcs;
6), on failure cable 3, produce damp oscillatory wave along failure cable 3 transmission and outside radiation field signal 13;
7), field signal pick-up unit 8 is connected the variation that field signal induction receiving coil 10 detects field signal 13 along failure cable 3 with field signal induction receiving coil 10;
8), the damped oscillation waveform 11 that has a reflection field signal to change of the left side before Method of Cable Trouble Point 5, this damped oscillation waveform 11 is presented on the display unit 9 of field signal pick-up unit 8;
9), the right side after Method of Cable Trouble Point 5, then be the damped oscillation waveform 12 of the rapid decay that changes of magnetic reaction fields signal, this sharply damped oscillation waveform 12 of decay be presented on the display unit 9 of field signal pick-up unit 8;
10), from Method of Cable Trouble Point 5 forward and backward wave form varies positions also with regard to 5 occurrence positions in trouble spot of corresponding failure cable 3 to be measured, promptly pairing cable position is exactly the position at Method of Cable Trouble Point place to field signal 13 from having to unconverted place.
Field signal pick-up unit 8 among Fig. 1 comprises display unit 9; Induction receiving coil 10; When if this device is used for the detection streamer trouble spot; What its display unit 9 began to show is the damped oscillation waveform 11 that trouble spot 5 is detected field signal 13 before; After device moves towards to move arrival trouble spot 5 along cable 3 paths; What display unit 9 showed at this moment is the damped oscillation waveform 12 of rapid attenuating mutation; For the clear damped oscillation waveform 11 that shows two variations; 12; Two field signal pick-up units 8 and display unit 9 have been drawn among Fig. 1; Have only a field signal pick-up unit 8 and display unit 9 on the actual device, display unit 9 in the trouble spot 5 as showing two kinds of different damped oscillation waveforms 11 before and after the separation; 12.When the path before device is used for the detection streamer trouble spot was moved towards, 9 of display units showed damped oscillation waveform 11.
Fig. 2, provided the relative position that field signal induction receiving coil 10 detects field signals 13 and failure cable 3 to be measured.
Fig. 3, provided field signal pick-up unit 8 and before the trouble spot 5 of cable 3, detected the waveform 11 that field signal 13 shows; This waveform is a damped oscillation waveform; When field signal pick-up unit 8 moves forward along failure cable 3; Field signal pick-up unit 8 has waveform 11 to show all the time; The waveform 11 rapid attenuating mutations of having crossed position field signal pick-up unit 8 demonstrations afterwards of trouble spot 5 are that waveform 12 shows that waveform sudden change place here and now is the position at Method of Cable Trouble Point place.
Fig. 4, provided when field signal pick-up unit 8 detects field signal 13 after the trouble spot 5 of cable 3 waveform 12 that shows; This waveform is the rapid decay waveform of waveform 11 damped oscillation waveforms; When field signal monitoring device 8 moves toward continued along failure cable 3 again, the waveform 12 that field signal pick-up unit 8 shows is decayed gradually and is become straight line.
During localization of fault; Apply periodic impacting with high pressure pulse signal in the fault of cable under test and screen layer or another fault between mutually; Because the distribution parameter characteristic of cable self and the balance of cable are relative; It must be to form damp oscillatory wave in the cable between signal source and trouble spot along cable transmission and to the external radiation signal that generates an electromagnetic field for the response of impacting with high pressure pulse signal; Forward position, trouble spot cable all can be received the field signal in this field signal 13, and the event of non-impact current loop does not have this field signal behind the trouble spot; Field signal pick-up unit with detecting this field signal variation begins along the variation of cable detection field signal from impacting with high pressure pulse signal source end; To the trouble spot, all should be able to receive the ripple field signal that damp oscillatory wave produces; And can not receive this field signal behind the trouble spot, pairing cable position is exactly the position at Method of Cable Trouble Point place to field signal from having to unconverted place.
Wherein, Consider that cable fault possibly occur in any position of cable; If occur in the top of cable; Inductance in the cable distribution parameter, electric capacity be very for a short time to be not enough to produce damp oscillatory wave; So impacting with high pressure pulse signal source output of the present invention should be connected in series the high pressure resonance reactor; In the impacting with high pressure pulse signal source commonly used pulsed capacitance is arranged all, as long as it is promptly available to increase the high pressure resonance reactor.
The field signal induction receiving coil 10 of described field signal pick-up unit must be an air core coil; One just can be detected; Two detections that can compare; Can also survey the cable louding path; But can use the field signal induction receiving coil 10 of ribbon core or magnetic core anything but, cause erroneous judgement otherwise can oneself produce damped oscillation.
Its coil plane should be parallel to cable under test when the field signal induction receiving coil 10 of described field signal pick-up unit used, and guaranteed that the magnetic line of force that characterizes field signal passes field signal induction receiving coil.
Embodiment 2
Field signal pick-up unit 8 of the present invention can also be used to the cable trace before the detection failure point; When field signal induction receiving coil 10 places on the cable under test position; Then waveform 11 amplitudes are maximum; Go ahead along ground this moment again; Pick-up unit has waveform 11 to show all the time; If pick-up unit does not have waveform 11 to show; The cable trace deflection is described; Should adjust the direction (left or right) of selecting cable trace, during waveform 11 amplitudes maximum magnetic field induction receiving coil 10 in the path on ground below it correspondence be exactly the path of underground cable.
Claims (1)
1. method with shock oscillation ripple principle detection streamer trouble spot is characterized in that being undertaken by following step:
1), the ground connection output terminal (1b) of common impacting with high pressure pulse signal source (1) is connected to the top ground wire (4) of failure cable to be measured (3);
2), the high-voltage output end (1a) of common impacting with high pressure pulse signal source (1) connects an end of high pressure resonance reactor (2);
3), the other end of high pressure resonance reactor (2) is connected to the fault phase (7) of failure cable to be measured; 4), the terminal ground wire (6) with failure cable to be measured (3) breaks off;
5), common impacting with high pressure pulse signal source (1) applies the impacting with high pressure pulse signal for failure cable to be measured (3) through high pressure resonance reactor (2), makes trouble spot (5) form instantaneous short circuit electric arc;
6), go up the generation damp oscillatory wave along failure cable (3) transmission and outside radiation field signal (13) at failure cable (3);
7), field signal pick-up unit (8) and field signal induction receiving coil (10) is connected, field signal induction receiving coil (10) is along the variation of failure cable (3) detection field signal (13);
8), the damped oscillation waveform (11) that has a reflection field signal change in Method of Cable Trouble Point (5) left side before, this damped oscillation waveform (11) is presented on the display unit (9) of field signal pick-up unit (8);
9), on Method of Cable Trouble Point (5) right side afterwards; Then be the damped oscillation waveform (12) of the rapid decay of magnetic reaction fields signal variation, this damped oscillation waveform (12) of sharply decaying is presented on the display unit (9) of field signal pick-up unit (8);
10), from the forward and backward wave form varies of Method of Cable Trouble Point (5) position also with regard to trouble spot (5) the institute occurrence positions of corresponding failure cable to be measured (3), promptly pairing cable position is exactly the position at Method of Cable Trouble Point place to field signal (13) from having to unconverted place.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110149078.6A CN102305901B (en) | 2011-06-03 | 2011-06-03 | Method for detecting cable fault point by impact oscillating wave principle |
| PCT/CN2011/001395 WO2012162862A1 (en) | 2011-06-03 | 2011-08-22 | Apparatus and application method for detecting cable fault point and path by using shock oscillation wave principle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110149078.6A CN102305901B (en) | 2011-06-03 | 2011-06-03 | Method for detecting cable fault point by impact oscillating wave principle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102305901A true CN102305901A (en) | 2012-01-04 |
| CN102305901B CN102305901B (en) | 2014-11-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201110149078.6A Active CN102305901B (en) | 2011-06-03 | 2011-06-03 | Method for detecting cable fault point by impact oscillating wave principle |
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| CN (1) | CN102305901B (en) |
| WO (1) | WO2012162862A1 (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102759686A (en) * | 2012-07-26 | 2012-10-31 | 山东科汇电力自动化有限公司 | Method for locating power cable faults |
| CN105182193A (en) * | 2015-08-24 | 2015-12-23 | 国网天津市电力公司 | owts testing method for short-time power failure of distribution power cable |
| CN105372555A (en) * | 2015-11-05 | 2016-03-02 | 国网山西省电力公司大同供电公司 | Electric power monitoring system having fault position detection function |
| CN105425106A (en) * | 2015-11-11 | 2016-03-23 | 国网山西省电力公司晋城供电公司 | Cable fault detection testing system and working method thereof |
| RU2585323C1 (en) * | 2015-03-27 | 2016-05-27 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Кубанский государственный технологический университет" (ФГБОУ ВПО "КубГТУ") | Device for determining damaged point of cable |
| CN105929308A (en) * | 2016-07-14 | 2016-09-07 | 广西电网有限责任公司柳州供电局 | Protecting layer grounding positioning instrument |
| WO2016201569A1 (en) * | 2015-06-19 | 2016-12-22 | HYDRO-QUéBEC | Method for locating a sparking fault in an underground electric line |
| CN111856208A (en) * | 2020-07-17 | 2020-10-30 | 山东科汇电力自动化股份有限公司 | Ultrahigh-voltage cable sheath fault point positioning device and method |
| CN112045107A (en) * | 2020-08-13 | 2020-12-08 | 无锡市华美电缆有限公司 | Intelligent shearing mechanism for cable |
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| CN103245875A (en) * | 2013-03-19 | 2013-08-14 | 湖南省电力公司永州冷水滩供电局 | Viewfinder for faults of wireless cable pipe trench |
| CN105699856B (en) * | 2016-04-18 | 2018-06-15 | 国网上海市电力公司 | A kind of cable fault positioning system and method based on intelligent acquisition with analysis |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102759686A (en) * | 2012-07-26 | 2012-10-31 | 山东科汇电力自动化有限公司 | Method for locating power cable faults |
| RU2585323C1 (en) * | 2015-03-27 | 2016-05-27 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Кубанский государственный технологический университет" (ФГБОУ ВПО "КубГТУ") | Device for determining damaged point of cable |
| WO2016201569A1 (en) * | 2015-06-19 | 2016-12-22 | HYDRO-QUéBEC | Method for locating a sparking fault in an underground electric line |
| CN105182193A (en) * | 2015-08-24 | 2015-12-23 | 国网天津市电力公司 | owts testing method for short-time power failure of distribution power cable |
| CN105372555A (en) * | 2015-11-05 | 2016-03-02 | 国网山西省电力公司大同供电公司 | Electric power monitoring system having fault position detection function |
| CN105372555B (en) * | 2015-11-05 | 2018-04-06 | 国网山西省电力公司大同供电公司 | A kind of electric power monitoring system with abort situation detection function |
| CN105425106A (en) * | 2015-11-11 | 2016-03-23 | 国网山西省电力公司晋城供电公司 | Cable fault detection testing system and working method thereof |
| CN105425106B (en) * | 2015-11-11 | 2018-02-09 | 国网山西省电力公司晋城供电公司 | A kind of Cable fault examination pilot system and its method of work |
| CN105929308A (en) * | 2016-07-14 | 2016-09-07 | 广西电网有限责任公司柳州供电局 | Protecting layer grounding positioning instrument |
| CN111856208A (en) * | 2020-07-17 | 2020-10-30 | 山东科汇电力自动化股份有限公司 | Ultrahigh-voltage cable sheath fault point positioning device and method |
| CN111856208B (en) * | 2020-07-17 | 2023-09-19 | 山东科汇电力自动化股份有限公司 | Device and method for positioning fault point of ultra-high voltage cable sheath |
| CN112045107A (en) * | 2020-08-13 | 2020-12-08 | 无锡市华美电缆有限公司 | Intelligent shearing mechanism for cable |
| CN112045107B (en) * | 2020-08-13 | 2022-11-01 | 无锡市华美电缆有限公司 | Intelligent shearing mechanism for cable |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2012162862A1 (en) | 2012-12-06 |
| CN102305901B (en) | 2014-11-12 |
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