CN2569162Y - Device for live detecting resistant current of three phase lighting arrestor - Google Patents
Device for live detecting resistant current of three phase lighting arrestor Download PDFInfo
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- CN2569162Y CN2569162Y CN 02264187 CN02264187U CN2569162Y CN 2569162 Y CN2569162 Y CN 2569162Y CN 02264187 CN02264187 CN 02264187 CN 02264187 U CN02264187 U CN 02264187U CN 2569162 Y CN2569162 Y CN 2569162Y
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Abstract
The utility model relates to a device for live detecting resistant current of three phase lighting arrestor, which comprises a signal sampling circuit, and a host computer composed of a monolithic computer, a data memory, a program memory, a liquid crystal display, a keyboard and a miniature printer, wherein, the signal sampling circuit comprises three signal sampling circuits composed of three zero input impedance circuits and three sample holding circuits. When the utility model is used, signal input terminals of the three zero input impedance circuits and ground wire terminal are respectively connected in series with mechanisms for counting thunders of the bottom of the three lightning arresters, or are connected in parallel with an online monitor by just using three double-core cables, which can realize to simultaneously detect the three lightning arresters in a three-phase circuit. A sampling signal is decomposed to a three-phase follow current base wave amplitude value and a three-phase follow current phase angle by the host computer, and the early failure of the lighting arrestor can be judged by analyzing and comparing three-phase follow current phase angle. The utility model has the advantages of convenient measure and operation, rapid judgment, high accuracy for judging an abnormal phase, etc., and is suitable for an earthed three-phase gapless metal oxide lightning arrester assembly connected in series with the mechanism for counting thunders, or connected in series with the on-line monitor.
Description
Technical field:
The utility model relates to the live line measurement device that a kind of AC electric power systems is used, and the device of three-phase gapless metal-oxide lighting arrester persistent current and current in resistance property thereof belongs to the electronic measuring instrument field in particularly a kind of live line measurement electric system.
Background technology:
Gapless metal-oxide lighting arrester is because of flowing into the earth rapidly with superpotential or lightning current, after thunder-strike current flows through or line voltage distribution recover just often, can recover insulating property again automatically fine is the very little advantages such as normal operating conditions of leakage current, now is widely used in high-voltage electric power system.Be that protection is sent out; transformer station and transmission line of electricity are avoided the visual plant of thunder and lightning and switching overvoltage harm; but lightning arrester all is to be connected between hi-line and the earth; performance is just often to not influence of circuit; in case degradation will on-call maintenance or replacing; otherwise be easy to breakdown short circuit and cause major accident; because of lightning arrester can not often remove inspection from circuit; deal with again after more can not waiting accident to take place; so must regularly measure the variation of its persistent current and current in resistance property thereof; for the diagnosis of gapless metal-oxide lighting arrester initial failure, the sensitiveest with the variation that detects current in resistance property.Therefore both at home and abroad manufacturer releases the instrument of various live line measurement current in resistance property one after another.The device of live line measurement arrester resistance current commonly used is mainly by signal sample circuit with by single-chip microcomputer at present, data-carrier store, program storage, LCD, the main frame that keyboard and mini-printer are formed is formed, lightning arrester persistent current signal is sent into the A/D converter of single-chip microcomputer in the main frame by signal sample circuit, the simulation conversion of signals is become digital signal, handle according to setting program by single-chip microcomputer, obtain the peak value of the total current of lightning arrester persistent current and current in resistance property thereof and by the LCD demonstration that circulates, by the operation to keyboard, mini-printer can print measurement result again.But, this class device carries out the device that phase analysis designs owing to adopting the signal of single-phase sampling and signal that voltage transformer (VT) is obtained, need be to A, B, the C three-phase is sampled measurements respectively, when being measured, every phase lightning arrester all needs to obtain voltage signal from this phase voltage mutual inductor secondary side, and with 90 ° of this signal phase shifts, with electric current after in addition subtract each other with the capacity current the persistent current that records the lightning arrester bottom mutually from this again as current in resistance property, obviously there are two problems in this device, 1: when each phase lightning arrester is detected respectively, all need to take out voltage signal from this phase voltage mutual inductor secondary side, and owing to voltage transformer (VT) is contained in from lightning arrester position far away, wiring is very inconvenient, also can cause serious consequences such as large-area power-cuts simultaneously, manipulate very inconvenient because of maloperation causes tripping operation; 2: since capacity current only this does not have in mutually, also contain mutually adjacent and non-the interference current of organizing contiguous charging equipment of this group, but not the interference current of the contiguous charging equipment of this group varies in different localities, the neither one definite value, though the angle of also taking this to be organized adjacent phase is revised, but still can't overcome the influence of those uncertain factors when measuring; 3: whether unusual because measurement result reflection is this phase lightning arrester situation of persistent current at that time, also need after the result who repeatedly measures is compared, could judge, so also there is shortcoming such as length measuring period.
Summary of the invention:
The purpose of this utility model is to manipulate weak point very inconvenient and that measuring period is long in order to overcome above-mentioned measurement mechanism, design a kind of need not and take out voltage signal from voltage transformer secondary side, only need to take out signal, just can measure three-phase lightning protector persistent current and current in resistance property simultaneously and can in time judge the whether normally device of live line measurement three-phase lightning protector current in resistance property of lightning arrester from the lightning stroke counter or the on-line monitoring device that are serially connected in three lightning arrester bottoms.
The device of live line measurement three-phase lightning protector current in resistance property of the present utility model mainly is to change single-phase sampling into three-phase sample simultaneously and persistent current and voltage transformer (VT) are obtained signal carry out phase analysis and change into and directly carry out phase analysis between the three-phase persistent current and form.Its structure is mainly by signal sample circuit with by single-chip microcomputer, data-carrier store, program storage, LCD, the main frame that keyboard and mini-printer are formed is formed, described signal sample circuit comprises three zero input impedance circuit and three three signal sample circuits that sampling hold circuit is formed, its signal annexation is: the input end of three zero input impedance circuit is that the signal input part of signal sample circuit is connected with three lightning stroke counters that are connected on three lightning arresters bottoms or on-line monitoring device respectively, the output terminal of three zero input impedance circuit is connected with the input end of three sampling hold circuits respectively, and the output terminal of three sampling hold circuits is that the signal output part of signal sample circuit is connected with three A/D converters in the single-chip microcomputer respectively.Wherein: each the zero input impedance circuit in three zero input impedance circuit has included an operational amplifier IC
1With a resistance R
1, each sampling hold circuit in three sampling hold circuits has included a sampling holder IC
2With three resistance R
2-R
4And capacitor C
1, its circuit connecting relation is: operational amplifier IC
1End of oppisite phase to be signal input part be connected IC with the lightning stroke counter or the on-line monitoring device that are connected on the lightning arrester bottom
1In-phase end be connected resistance R with the earth terminal of lightning stroke counter or on-line monitoring device
1Be connected on IC
1End of oppisite phase and IC
1Output terminal between, IC
1Output terminal through resistance R
2With sampling holder IC
2The 3rd pin be that input end connects, sampling holder IC
2The 6th foot meridian capacitor C
1Be connected R with ground
3Be connected on IC
2Between the 3rd pin and the power supply, R
4Two terminate at IC
2Between the 1st pin and the ground, R
4Intermediate ends and IC
2The 2nd pin connect sampling holder IC
2The 5th pin be output terminal be signal sample circuit signal output part be connected sampling holder IC with A/D converter in the single-chip microcomputer
2The 8th pin be that the controlling of sampling pulse input end is connected with the controlling of sampling pulse output end of single-chip microcomputer.Circuit and interconnected relationship thereof for single-chip microcomputer, data-carrier store, program storage, LCD, keyboard and mini-printer are same as the prior art, are not described in detail at this.During use, only need with three two-wire cables respectively with the signal input part and the ground terminal of three zero input impedance circuit be serially connected in lightning stroke counter bottom three lightning arresters or on-line monitoring device and be connected in parallel and get final product.During measurement, three-phase lightning protector persistent current signal is delivered to three zero input impedance circuit respectively through three two-wire cables, thereby the whole persistent currents that guarantee lightning arrester all flow into measurement mechanism, through zero input impedance circuit current signal is converted to voltage signal, deliver to three sampling hold circuits respectively, sampling and maintenance when three sampling hold circuits are subjected to the control of the sampling holding signal of single-chip microcomputer to realize three-phase signal, guarantee the simultaneity of three-phase signal sampling is beneficial to single-chip microcomputer the phase place of three-phase current be judged; The simulation signal of three sampling hold circuit outputs converts digital signal to through the multichannel A/D converter, whether unusual situation shows by the LCD circulation with each phase persistent current and resistive component and lightning arrester to the processing of acquired signal by single-chip microcomputer, measurement result can be printed by mini-printer by Keyboard Control simultaneously.
The utility model is as long as be connected in parallel with the lightning stroke counter or the on-line monitoring device that are serially connected in three lightning arrester bottoms respectively with the signal input part of three two-wire cables with three signal sample circuits, can realize simultaneously the persistent current of three lightning arresters in the three-phase high-voltage circuit is detected, need not to take out voltage signal from voltage transformer secondary side again, therefore can avoid fully taking out the shortcoming that voltage signal produced from voltage transformer secondary side, make measuring operation very convenient, and because of the three-phase lightning protector persistent current is sampled simultaneously device is implemented in directly to carry out phase analysis between the three-phase relatively, three-phase line can be subjected to simultaneously this group adjacent mutually and non-group interference current of being close to the no determined value of charging equipment cancel out each other and the error problem that overcomes so produce, sampled signal decomposites three-phase persistent current fundamental voltage amplitude and phase angle through main frame, by three-phase persistent current phase angle is analyzed comparison, can judge that 1. the resistive component of three-phase is normal; 2. have one mutually unusual in the three-phase; 3. there is two-phase unusual in the three-phase; 4. the equal initial failure of all unusual but unusual degree of three-phase, it is convenient to have measuring operation, swift with judgement with judge unusual correctness advantages of higher mutually, the three-phase gapless metal-oxide lighting arrester group that is fit to be in series with lightning stroke counter or on-line monitoring device ground connection is used.
Description of drawings:
Accompanying drawing 1 is the structural representation that the utility model is measured A, B, C three-phase lightning protector;
Embodiment:
Referring to accompanying drawing 1, in the accompanying drawing 1 the 1,2, the 3rd, three gapless metal-oxide lighting arresters of A, B, C three-phase line, 4, the 5, the 6th, be connected in three lightning stroke counters or on-line monitoring device between three gapless metal-oxide lighting arresters and the ground respectively, 7,8,9 is three two-wire cables, 10,11,12 is three signal sample circuits, the 13rd, the multichannel A/D converter, the 14th, single-chip microcomputer, the 15th, LCD, the 16th, mini-printer, 17 data-carrier stores, the 18th, program storage, the 19th, keyboard.Described signal sample circuit comprises three zero input impedance circuit and three three signal sample circuits 10 that sampling hold circuit is formed, 11 and 12, its signal annexation is: the input end of three zero input impedance circuit is three signal sample circuits 10,11,12 signal input part respectively be connected on three lightning arresters 1,2, three lightning stroke counters of 3 bottoms or on- line monitoring device 4,5,6 connect, the output terminal of three zero input impedance circuit is connected with the input end of three sampling hold circuits respectively, and the output terminal of three sampling hold circuits is three signal sample circuits 10,11,12 signal output part is connected with three A/D converters 13 in the single-chip microcomputer 14 respectively.During use, a heart yearn of three two- wire cable lines 7,8,9 that will be connected with the signal input part of three signal sample circuits 10,11,12 is connected with the bottom of three lightning arresters 1,2,3 of A, B, C three-phase line respectively, another root heart yearn of the two-wire cable that will be connected with the earth terminal of three signal sample circuits is connected the shielding layer grounding of two-wire cable with the bottom of A, B, C three-phase lightning stroke counter or on-line monitoring device respectively.Accompanying drawing 2 is circuit diagrams of a signal sample circuit in three signal sample circuits 10,11,12 in the accompanying drawing 1, described signal sample circuit comprises three zero input impedance circuit and three sampling hold circuits, and each the zero input impedance circuit in three zero input impedance circuit has included an operational amplifier IC
1With a resistance R
1, each sampling hold circuit in three sampling hold circuits has included a sampling holder IC
2With three resistance R
2-R
4And capacitor C
1, its circuit connecting relation is: operational amplifier IC
1The lightning stroke counter or the on-line monitoring device of inverting input and lightning arrester bottom series connection be connected IC
1In-phase input end be connected resistance R with the earth terminal of lightning stroke counter or on-line monitoring device
1Be connected on IC
1Inverting input and IC
1Between the output terminal, IC
1Output terminal through resistance R
2With sampling holder IC
2The 3rd pin be that input end connects, sampling holder IC
2The 6th foot meridian capacitor C
1Be connected R with ground
3Be connected on IC
2Between the 3rd pin and the power supply, R
4Two terminate between power supply and the ground R
4Intermediate ends and IC
2The 2nd pin connect sampling holder IC
2The 5th pin to be output terminal be connected sampling holder IC with multichannel A/D converter A/D in the single-chip microcomputer
2The 8th pin be that the controlling of sampling pulse input end is connected with the controlling of sampling pulse output end of singlechip CPU.Described zero input impedance circuit is actually input impedance is adjusted into zero a kind of negative-feedback amplifier, the operational amplifier IC in the circuit
1Select the high precision operating amplifier of OP-07 or models such as TL061 or TL071 or TL081 for use, sampling holder IC
2Select for use LF298 or LF398 or AD582 or AD583 to wait until the sampling holder of model.Circuit and interconnected relationship thereof for single-chip microcomputer, data-carrier store, program storage, LCD, keyboard and mini-printer are same as the prior art, are not described in detail at this.During measurement, three road leakage current of an arrester signals are delivered to three zero input impedance circuit respectively through three two-wire cables, thereby the whole leakage currents that guarantee lightning arrester all flow into measurement mechanism, zero input impedance translation circuit is converted to voltage signal with current signal simultaneously, deliver to three road sampling hold circuits respectively, sampling and maintenance when three road sampling hold circuits are subjected to the controlling of sampling pulse control of single-chip microcomputer to realize three road signals, guarantee simultaneity, help the phase place of three road electric currents being judged with single-chip microcomputer to three road signal samplings; Sampling hold circuit converts the multichannel A/D converter that the simulation signal outputs to single-chip microcomputer to digital signal, realizes the collection to three road signals.Single-chip microcomputer 14 is by comparing to the processing of acquired signal with data-carrier store 17 and controlled by program storage, select different modified values, compare by analysis the three-phase current phase angle, each phase total current and current in resistance property are shown by LCD 15 circulations, and can judge rapidly that 1. the resistive component of three-phase is normal; 2. have one mutually unusual in the three-phase; 3. there is two-phase unusual in the three-phase; 4. the equal initial failure of all unusual but unusual degree of three-phase.Measurement result can be printed by mini-printer 16 by keyboard 19 controls.It is convenient to the utlity model has measuring operation, swift with judgement and judge unusual correctness advantages of higher mutually, is fit to be in series with the three-phase gapless metal-oxide lighting arrester group use of lightning stroke counter or on-line monitoring device ground connection.
Claims (2)
1, a kind of device of live line measurement three-phase lightning protector current in resistance property, comprise signal sample circuit and by single-chip microcomputer, data-carrier store, program storage, LCD, the main frame that keyboard and mini-printer are formed is formed, it is characterized in that signal sample circuit comprises three zero input impedance circuit and three three signal sample circuits that sampling hold circuit is formed, its signal annexation is: the input end of three zero input impedance circuit is that the signal input part of signal sample circuit is connected with three lightning stroke counters that are connected on three lightning arresters bottoms or on-line monitoring device respectively, the output terminal of three zero input impedance circuit is connected with the input end of three sampling hold circuits respectively, and the output terminal of three sampling hold circuits is that the signal output part of signal sample circuit is connected with three A/D converters in the single-chip microcomputer respectively.
2, the device of live line measurement three-phase lightning protector current in resistance property as claimed in claim 1 is characterized in that each the zero input impedance circuit in three the zero input impedance circuit has included an operational amplifier IC
1With a resistance R
1, each sampling hold circuit in three sampling hold circuits has included a sampling holder IC
2With three resistance R
2-R
4And capacitor C
1, its circuit connecting relation is: operational amplifier IC
1End of oppisite phase to be signal input part be connected IC with the lightning stroke counter or the on-line monitoring device that are connected on the lightning arrester bottom
1In-phase end be connected resistance R with the earth terminal of lightning stroke counter or on-line monitoring device
1Be connected on IC
1End of oppisite phase and IC
1Output terminal between, IC
1Output terminal through resistance R
2With sampling holder IC
2The 3rd pin be that input end connects, sampling holder IC
2The 6th foot meridian capacitor C
1Be connected R with ground
3Be connected on IC
2Between the 3rd pin and the power supply, R
4Two terminate at IC
2Between the 1st pin and the ground, R
4Intermediate ends and IC
2The 2nd pin connect sampling holder IC
2The 5th pin be that to be the signal output part of signal sample circuit be connected sampling holder IC with A/D converter in the single-chip microcomputer to output terminal
2The 8th pin be that the controlling of sampling pulse input end is connected with the controlling of sampling pulse output end of single-chip microcomputer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02264187 CN2569162Y (en) | 2002-09-06 | 2002-09-06 | Device for live detecting resistant current of three phase lighting arrestor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02264187 CN2569162Y (en) | 2002-09-06 | 2002-09-06 | Device for live detecting resistant current of three phase lighting arrestor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2569162Y true CN2569162Y (en) | 2003-08-27 |
Family
ID=33730432
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02264187 Expired - Fee Related CN2569162Y (en) | 2002-09-06 | 2002-09-06 | Device for live detecting resistant current of three phase lighting arrestor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2569162Y (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100460883C (en) * | 2004-12-29 | 2009-02-11 | 上海电气自动化设计研究所有限公司 | Detection method for testing current in resistance property of lightning arrester |
| CN102495272A (en) * | 2011-12-11 | 2012-06-13 | 河南省电力公司平顶山供电公司 | Testing method for lightning counters |
| CN101403777B (en) * | 2008-11-05 | 2012-07-04 | 四川电力试验研究院 | Resistive current tester for great current zinc oxide lightning arrester |
| CN102830319A (en) * | 2012-09-18 | 2012-12-19 | 辽宁省电力有限公司电力科学研究院 | Device and method for on-line inspection on insulation state of zinc oxide arrester |
| CN103777064A (en) * | 2014-01-23 | 2014-05-07 | 国家电网公司 | Zinc oxide arrester live detection device free of external connection with alternating-current power supply |
| CN104865438A (en) * | 2015-06-15 | 2015-08-26 | 江苏理工学院 | Measurement method of zinc oxide arrester resistive current fundamental wave |
| CN104931782A (en) * | 2015-06-16 | 2015-09-23 | 江苏理工学院 | Remote asynchronous power frequency signal phase difference measurement method and system |
| CN105467197A (en) * | 2015-12-29 | 2016-04-06 | 国家电网公司 | Online monitoring device of integrated lightning arrester |
| CN108333455A (en) * | 2018-04-08 | 2018-07-27 | 广东电网有限责任公司 | A kind of measuring device with electricity for three-phase alternating current metal oxide arrester group |
| CN109061349A (en) * | 2018-08-08 | 2018-12-21 | 国网湖南省电力有限公司 | A kind of 10 KV lightning arrester three-phase test devices |
| CN113721100A (en) * | 2021-09-18 | 2021-11-30 | 国网安徽省电力有限公司马鞍山供电公司 | Lightning arrester online monitoring device capable of performing fault early warning and control method thereof |
-
2002
- 2002-09-06 CN CN 02264187 patent/CN2569162Y/en not_active Expired - Fee Related
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100460883C (en) * | 2004-12-29 | 2009-02-11 | 上海电气自动化设计研究所有限公司 | Detection method for testing current in resistance property of lightning arrester |
| CN101403777B (en) * | 2008-11-05 | 2012-07-04 | 四川电力试验研究院 | Resistive current tester for great current zinc oxide lightning arrester |
| CN102495272A (en) * | 2011-12-11 | 2012-06-13 | 河南省电力公司平顶山供电公司 | Testing method for lightning counters |
| CN102830319B (en) * | 2012-09-18 | 2016-02-24 | 辽宁省电力有限公司电力科学研究院 | A kind of zinc oxide lightning arrester insulation state measuring device with electricity and method |
| CN102830319A (en) * | 2012-09-18 | 2012-12-19 | 辽宁省电力有限公司电力科学研究院 | Device and method for on-line inspection on insulation state of zinc oxide arrester |
| CN103777064A (en) * | 2014-01-23 | 2014-05-07 | 国家电网公司 | Zinc oxide arrester live detection device free of external connection with alternating-current power supply |
| CN104865438A (en) * | 2015-06-15 | 2015-08-26 | 江苏理工学院 | Measurement method of zinc oxide arrester resistive current fundamental wave |
| CN104931782A (en) * | 2015-06-16 | 2015-09-23 | 江苏理工学院 | Remote asynchronous power frequency signal phase difference measurement method and system |
| CN105467197A (en) * | 2015-12-29 | 2016-04-06 | 国家电网公司 | Online monitoring device of integrated lightning arrester |
| CN105467197B (en) * | 2015-12-29 | 2018-10-19 | 国家电网公司 | Integrated arrester on-Line Monitor Device |
| CN108333455A (en) * | 2018-04-08 | 2018-07-27 | 广东电网有限责任公司 | A kind of measuring device with electricity for three-phase alternating current metal oxide arrester group |
| CN109061349A (en) * | 2018-08-08 | 2018-12-21 | 国网湖南省电力有限公司 | A kind of 10 KV lightning arrester three-phase test devices |
| CN113721100A (en) * | 2021-09-18 | 2021-11-30 | 国网安徽省电力有限公司马鞍山供电公司 | Lightning arrester online monitoring device capable of performing fault early warning and control method thereof |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |