CN202649380U - Digital cable insulation fault automatic locator - Google Patents
Digital cable insulation fault automatic locator Download PDFInfo
- Publication number
- CN202649380U CN202649380U CN 201220247296 CN201220247296U CN202649380U CN 202649380 U CN202649380 U CN 202649380U CN 201220247296 CN201220247296 CN 201220247296 CN 201220247296 U CN201220247296 U CN 201220247296U CN 202649380 U CN202649380 U CN 202649380U
- Authority
- CN
- China
- Prior art keywords
- circuit
- power supply
- voltage power
- electric bridge
- digital
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
The utility model relates to a digital cable insulation fault automatic locator which includes a high voltage power supply and a low voltage power supply. After the low voltage power supply is connected in series with a first switch, and low voltage power supply provides power for a first electric bridge used for measuring the cable length. After the high voltage power supply is connected in series with a second switch, the high voltage power supply is connected to a second electric bridge used for fault positioning. A digital potentiometer is taken as a public arm of the first electric bridge and the second electric bridge. A detection control portion comprises the digital potentiometer as the public arm and a detection control circuit. Two fixed terminals of the digital potentiometer are connected to any two phases of a cable to be measure, and one of the phases is a fault phase. A sliding terminal of the digital potentiometer is connected to the output of the high voltage power supply. A control output terminal of the detection control circuit is connected to the sliding terminal of the digital potentiometer. A detection signal terminal of the detection control circuit is connected to two ends of the electric bridges, namely, is connected in parallel two the two fixed terminals of the potentiometer. The digital cable insulation fault automatic locator integrates the cable length measuring and the cable insulation fault positioning in one body, and is cheaper and easier to operate than the current tester.
Description
Technical field
The utility model relates to a kind of cable insulation fault detection technique, particularly a kind of digital cable insulation fault automatic position indicator.
Background technology
Current, because shortage of land resource, simultaneously for beautifying the environment, power cable also is widely used in China, power cable will directly affect the safe operation of whole electric system in case break down, if fault discovery is untimely as the important component part of electric system, may cause the larger damage sequences such as fire, massive blackout, bring immeasurable loss to national economy.
Method commonly used is to adopt row wave measurement method at present, this just requires relevant practitioner to have skilled measuring technology and abundant practical experience, the identification of traveling wave method fault test waveform is cable fault detect personnel's a difficult problem always, because the waveform of cable fault detect is complicated, the identification difficulty is large, the tester needs could be competent at through professional training, so the tester is had relatively high expectations.In addition, the staff quality that a present part is engaged in cable maintenance, maintenance is not high, understands not deep enough to modern test method principle, equipment, using method.In case the generation cable fault, these unfavorable factors will be incured loss through delay the power system restoration power-on time, cause damage to national economy, bring to people's lives to have a strong impact on.Therefore, design a kind of low cost and make things convenient for easy-operating equipment to come the positioning cable fault with regard to exigence.
Summary of the invention
The utility model is the problem for cable insulation fault detection method complexity, has proposed a kind of digital cable insulation fault automatic position indicator, is a kind of novel test device that utilizes the cable insulation fault of resistance bridge principle test low-resistance and high resistant.
The technical solution of the utility model is: a kind of digital cable insulation fault automatic position indicator, comprise power supply, two electric bridges and detect control section, power supply comprises high-voltage power supply and low-tension supply, after the low-tension supply series connection the first switch after, give the power supply of the first electric bridge of measuring cable length, after the high-voltage power supply series connection second switch after, connect the second electric bridge of localization of fault, digital regulation resistance is as the public arm of the first electric bridge and the second electric bridge, the detection control section comprises as the digital regulation resistance of public arm and detects control circuit, two stiff ends of digital regulation resistance are connected to any two-phase of tested cable, wherein one is fault phase, and the sliding end of digital regulation resistance connects the output of high-voltage power supply; The control output end of detecting control circuit is connected to the sliding end of digital regulation resistance, and the detection signal that detects control circuit terminates at the two ends of electric bridge, namely is parallel to two stiff ends of potentiometer.
Described detection control circuit comprises current collection circuit and detection signal treatment circuit, and current collection circuit comprises the sample resistance and the amplifying circuit of successively series connection and the follow circuit that links to each other with amplifying circuit that connects high-voltage power supply output; The input of detection signal treatment circuit connects digital regulation resistance two stiff ends, and detection signal treatment circuit test electric bridge both end voltage signal passes through first order amplifying circuit, filtering circuit and second level amplifying circuit successively; Wherein the output of second level amplifying circuit is connected the output of follow circuit and is connected a high-speed a/d sample circuit with current collection circuit, the output terminal of high-speed a/d sample circuit links to each other with the input end of control system with the CPU analysis that shows with one, CPU analyzes the sliding end that is connected digital regulation resistance with a control output of control system, and another is controlled to export by digital regulation resistance and links to each other with second amplifying circuit input end in the detection signal treatment circuit.
The beneficial effects of the utility model are: the digital cable insulation fault of the utility model automatic position indicator is lower and easy to operate than existing tester cost.
Description of drawings
Fig. 1 is the schematic diagram that the digital cable insulation fault of the utility model automatic position indicator is measured cable length;
Fig. 2 is that the digital cable insulation fault of the utility model automatic position indicator is measured the cable length equivalent circuit diagram;
Fig. 3 is the schematic diagram that the digital cable insulation fault of the utility model automatic position indicator is measured the cable insulation fault distance;
Fig. 4 is the equivalent circuit diagram that the digital cable insulation fault of the utility model automatic position indicator is measured the cable insulation fault distance;
Fig. 5 is the functional block diagram of the digital cable insulation fault of the utility model automatic position indicator Detection ﹠ Controling circuit;
Fig. 6 is the digital cable insulation fault of the utility model automatic position indicator circuit theory diagrams.
Embodiment
This device be the linear measure longimetry of current collection cable and cable insulation localization of fault in one, namely this device will be measured cable length before measuring the insulation fault distance, this two step all is based on electrical bridge principle, so this principle of device is two simple electric bridges.Fig. 1 is for measuring the schematic diagram of cable length, and whether Fig. 2 is zero for its equivalent circuit diagram according to the magnitude of voltage at measuring bridge two ends, and the digital regulation resistance that slides is so that bridge balance:
(1) (r represents slide potentiometer among Fig. 2, r=r1+r2)
R1 wherein, r2 is the digital regulation resistance arm resistance; R4 is fixed value resistance, and r5 is 2 times cable core resistance; Can get
Wherein S is the sectional area of cable, and unit is
Be the cable conduction coefficient.20 ° of C the time copper core cable electrical conductivity be
, the electrical conductivity of Lv Xin cable is
Can draw
(4)
Fig. 3 is the schematic diagram of measuring the cable insulation fault, Fig. 4 be its equivalent schematic diagram (should be for R represents slide potentiometer among Fig. 4, R=R1+R2, r3 and r6 among the figure are respectively
).When bridge balance:
Have
, because cable core resistance and cable core length are directly proportional, so obtain fault distance:
(5), among Fig. 4
Be insulation resistance value.
High-voltage power supply among Fig. 3 comprises the transformer TV that links to each other with pressure regulator T; Be connected to the elementary voltage table PV of transformer TV; Be connected in the transformer TV secondary loop reometer PA, rectification silicon stack V and to earth capacitance filtering C.
As shown in Figure 5, detect control circuit and comprise current sampling resistor TT the two ends current collection circuit 5 that takes out and the detection signal treatment circuit 4 that is connected to the test electric bridge both end voltage of 3 liang of stiff ends of digital regulation resistance of connecting with high-voltage power supply output.Current collection circuit 5 comprises the sample resistance and the amplifying circuit of successively series connection and the follow circuit that links to each other with amplifying circuit that connects high voltage output.Detection signal treatment circuit 4 comprises first order amplifying circuit, filtering circuit and second level amplifying circuit successively, wherein the output of second level amplifying circuit is connected the output of follow circuit and is connected a high-speed a/d sample circuit 6 with current collection circuit, and the output terminal of high-speed a/d sample circuit 6 is analyzed with the CPU that shows and to be linked to each other with the input end of control system 7 with one.CPU analyzes the sliding end that is connected digital regulation resistance 3 with a control output of control system 7; Another control output links to each other with second amplifying circuit input end in the detection signal treatment circuit 4 by digital regulation resistance.
Fig. 6 is the schematic diagram of whole device, digital cable insulation fault automatic position indicator, comprise power supply, two electric bridges and detect control section, power supply comprises high-voltage power supply 2 and low-tension supply 1, behind the low-tension supply 1 rear tandem tap A1, give the power supply of the electric bridge of measuring cable length, behind the high-voltage power supply 2 rear tandem tap A2, use for the electric bridge of localization of fault, the detection control section comprises as a digital regulation resistance 3 of bridge arm and detects control circuit, two stiff ends of digital regulation resistance 3 are connected to any two-phase of tested cable, and wherein one is fault phase, and the sliding end of this digital regulation resistance 3 connects the output of high voltage part; The control end that detects control circuit is connected to the sliding end of digital regulation resistance 3, and the detection signal that detects control circuit terminates at the two ends of electric bridge, namely is parallel to two stiff ends of potentiometer.
When measuring cable length, switch A1 is closed, the electric bridge brachium pontis is equivalent to S2 and S4 is closed, this moment, the electric bridge arm resistance was r1, r2, r4, r5. equivalent electrical circuit such as Fig. 2, the balance of electric bridge is whether the magnitude of voltage by the measuring bridge two ends is zero digital regulation resistance that slides, so that bridge balance, two resistance of the digital regulation resistance that read this moment are r1 and r2, behind the cable length that CPU measures, store, at this moment disconnect A1, S7, Closing Switch A2, this moment is for measuring the electric bridge of cable insulation fault, this electric bridge arm resistance is equivalent to disconnect S2, S4, closed S1, S3, its equivalent circuit diagram such as Fig. 4.
Claims (2)
1. digital cable insulation fault automatic position indicator, it is characterized in that, comprise power supply, two electric bridges and detect control section, power supply comprises high-voltage power supply and low-tension supply, after the low-tension supply series connection the first switch after, give the power supply of the first electric bridge of measuring cable length, after the high-voltage power supply series connection second switch after, connect the second electric bridge of localization of fault, digital regulation resistance is as the public arm of the first electric bridge and the second electric bridge, the detection control section comprises as the digital regulation resistance of public arm and detects control circuit, two stiff ends of digital regulation resistance are connected to any two-phase of tested cable, wherein one is fault phase, and the sliding end of digital regulation resistance connects the output of high-voltage power supply; The control output end of detecting control circuit is connected to the sliding end of digital regulation resistance, and the detection signal that detects control circuit terminates at the two ends of electric bridge, namely is parallel to two stiff ends of potentiometer.
2. described digital cable insulation fault automatic position indicator according to claim 1, it is characterized in that, described detection control circuit comprises current collection circuit and detection signal treatment circuit, and current collection circuit comprises the sample resistance and the amplifying circuit of successively series connection and the follow circuit that links to each other with amplifying circuit that connects high-voltage power supply output; The input of detection signal treatment circuit connects digital regulation resistance two stiff ends, and detection signal treatment circuit test electric bridge both end voltage signal passes through first order amplifying circuit, filtering circuit and second level amplifying circuit successively; Wherein the output of second level amplifying circuit is connected the output of follow circuit and is connected a high-speed a/d sample circuit with current collection circuit, the output terminal of high-speed a/d sample circuit links to each other with the input end of control system with the CPU analysis that shows with one, CPU analyzes the sliding end that is connected digital regulation resistance with a control output of control system, and another is controlled to export by digital regulation resistance and links to each other with second amplifying circuit input end in the detection signal treatment circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220247296 CN202649380U (en) | 2012-05-30 | 2012-05-30 | Digital cable insulation fault automatic locator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220247296 CN202649380U (en) | 2012-05-30 | 2012-05-30 | Digital cable insulation fault automatic locator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202649380U true CN202649380U (en) | 2013-01-02 |
Family
ID=47418471
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220247296 Expired - Fee Related CN202649380U (en) | 2012-05-30 | 2012-05-30 | Digital cable insulation fault automatic locator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202649380U (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103743997A (en) * | 2013-12-23 | 2014-04-23 | 柳州职业技术学院 | Low-voltage cable fault flaw detector |
| CN105891675A (en) * | 2016-04-11 | 2016-08-24 | 中国石油大学(华东) | Method of positioning insulated fault point of submersible oil cable in twice Wheatstone bridge method |
| CN106353643A (en) * | 2016-11-09 | 2017-01-25 | 雷细军 | Resistance proportion cable fault tester |
| CN106443351A (en) * | 2016-11-02 | 2017-02-22 | 南京工程学院 | System and method for detecting faults of multi-core cables of ships |
| CN109001519A (en) * | 2018-09-10 | 2018-12-14 | 国网江苏省电力有限公司电力科学研究院 | A kind of electrification positioning cable outer jacket breaks the apparatus and method of protective metal shell grounding point outside |
| CN109342805A (en) * | 2018-11-21 | 2019-02-15 | 陕西电器研究所 | A kind of high-precision micro-ampere current detection circuit |
| CN111623954A (en) * | 2020-04-30 | 2020-09-04 | 中国航天空气动力技术研究院 | Wind tunnel balance bridge fault detection method |
-
2012
- 2012-05-30 CN CN 201220247296 patent/CN202649380U/en not_active Expired - Fee Related
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103743997A (en) * | 2013-12-23 | 2014-04-23 | 柳州职业技术学院 | Low-voltage cable fault flaw detector |
| CN105891675A (en) * | 2016-04-11 | 2016-08-24 | 中国石油大学(华东) | Method of positioning insulated fault point of submersible oil cable in twice Wheatstone bridge method |
| CN106443351A (en) * | 2016-11-02 | 2017-02-22 | 南京工程学院 | System and method for detecting faults of multi-core cables of ships |
| CN106353643A (en) * | 2016-11-09 | 2017-01-25 | 雷细军 | Resistance proportion cable fault tester |
| CN106353643B (en) * | 2016-11-09 | 2019-05-28 | 雷细军 | Resistance ratio electric cable failure detector |
| CN109001519A (en) * | 2018-09-10 | 2018-12-14 | 国网江苏省电力有限公司电力科学研究院 | A kind of electrification positioning cable outer jacket breaks the apparatus and method of protective metal shell grounding point outside |
| CN109001519B (en) * | 2018-09-10 | 2024-01-05 | 国网江苏省电力有限公司电力科学研究院 | Device and method for locating grounding point of cable metal sheath in electrified manner |
| CN109342805A (en) * | 2018-11-21 | 2019-02-15 | 陕西电器研究所 | A kind of high-precision micro-ampere current detection circuit |
| CN109342805B (en) * | 2018-11-21 | 2020-12-22 | 陕西电器研究所 | High-precision microampere current detection circuit |
| CN111623954A (en) * | 2020-04-30 | 2020-09-04 | 中国航天空气动力技术研究院 | Wind tunnel balance bridge fault detection method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202649380U (en) | Digital cable insulation fault automatic locator | |
| CN104678341A (en) | Detection device and detection method for station-dedicated DC power system insulation monitoring device | |
| CN104330677B (en) | A kind of electronic current mutual inductor experimental rig and test method | |
| CN104237738A (en) | Distribution feeder single-phase grounding location system and location method | |
| CN202975229U (en) | Multipoint earthing detection locator for secondary circuits of transformer substations | |
| CN204515113U (en) | Stand with the pick-up unit of DC power system insulation monitoring and warning device | |
| CN101614798A (en) | Polarity detection system of electronic transformer | |
| CN101504429B (en) | Portable on-line measurement instrument for electrician electric bridge drain voltage | |
| CN105182173B (en) | Novel composite mutual inductor polarity tester | |
| CN104034977B (en) | Capacitance type potential transformer live detection instrument | |
| CN203587684U (en) | Single-phase electricity meter metering protection circuit | |
| CN204832412U (en) | Novel combined instrument transformer polarity test appearance | |
| CN208172234U (en) | A kind of no-load voltage ratio of current transformer, Check up polarity experimental rig | |
| CN202502189U (en) | Low voltage line leakage fault seeking device | |
| CN203572957U (en) | On-site meter calibration system | |
| CN205176140U (en) | Be applied to insulation resistance detector of IT system | |
| CN102749523A (en) | Direct-current ground resistance detection circuit applied to photovoltaic inverter system | |
| CN108776320A (en) | A kind of no-load voltage ratio of current transformer, Check up polarity test method and device | |
| CN107957568A (en) | Secondary Circuit of Potential Transformer multipoint earthing Quick positioning instrument and lookup method | |
| CN104880686A (en) | Device and method for checking portable electronic current transformer | |
| CN111751715B (en) | Be applied to primary loop detection device of circuit breaker | |
| CN204719222U (en) | A kind of portable electronic piece formula current transformer calibration device | |
| CN107817463A (en) | A kind of electricity anti-theft method for detecting short circuit electric energy meter | |
| CN201464596U (en) | Electronic transducer polarity detecting system | |
| CN210835070U (en) | Bus duct impedance measuring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130102 Termination date: 20150530 |
|
| EXPY | Termination of patent right or utility model |