CN101320070A - Indication method and device of short circuit and ground fault of power distribution network - Google Patents
Indication method and device of short circuit and ground fault of power distribution network Download PDFInfo
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- CN101320070A CN101320070A CNA2008100714222A CN200810071422A CN101320070A CN 101320070 A CN101320070 A CN 101320070A CN A2008100714222 A CNA2008100714222 A CN A2008100714222A CN 200810071422 A CN200810071422 A CN 200810071422A CN 101320070 A CN101320070 A CN 101320070A
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Abstract
The invention discloses a method and a device for indicating the short circuit of lines and earth fault of distribution network. The method provided by the invention is the method which adopts the instantaneous variation of current and voltage to start circuits. The device provided by the invention is the device which adopts the instantaneous variation of current and voltage to start circuits. The method and the device provided by the invention have the advantages that the technical proposal that the instantaneous variation of current and voltage is used to start circuit can improve the rate of the correct action of the device and shorten the failure searching time, thereby improving the reliability of the power supply of the distribution network system. The invention provides the method for directly measuring the overhead line to earth voltage, so that the earth fault of lines can be distinguished more directly and reliably.
Description
Technical field
The present invention relates to a kind of detection method and device of electric system, especially for the indicating means and the indicating device of indication power distribution network line short and earth fault.
Background technology
In the electric system of 10kV power distribution network, short circuit and earth fault are the major failures of power distribution network circuit, and these faults impact system, cause the power failure of certain limit.If in system, can in time detect fault and keep in repair, will shorten faulty equipment and stop the labour time, improve operational efficiency and power supply reliability.At present to short circuit and the existing argumentation of earth-fault indicator, as patent ZL99122276.8 supply line singlephase earth fault display packing and used instrument, introduced and adopted relatively ground connection moment capacitance current and the first half-wave of voltage, compare its phase place and, be judged as the fault detector of fault when the capacitance current sudden change and greater than certain numerical value.This failure judgment device, the distribution network systems that arc suppression coil especially has been installed for neutral point, the product performance factor is low.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art part and a kind of product performance factor height is provided, power distribution network line short and earth fault indicating means and indicating device that trouble shooting time is short.
A kind of power distribution network line short and earth fault indicating means is characterized in that: described method is a kind of electric current, voltage transient amount start-up circuit method.
Described method is specially: certain the root lead that the magnetic circuit of current sensor is surrounded electric distribution network overhead wire, the current signal of this lead of its secondary winding output is connected to the input end of current signal transducer, the current signal transducer is transformed into single-chip computer control system acceptable voltage signal with the current signal that samples, send the A/D passage 1 of single-chip computer control system and the input end of current transients amount start-up circuit respectively, the output terminal Xout of current transients amount start-up circuit connects interruption 0 pin of single-chip computer control system; Same lead of the sampling capacitor one termination electric distribution network overhead wire of voltage sensor, another termination metal matter casing, form sampling capacitor and the casing series circuit of distributed capacitance over the ground, this lead voltage-to-ground signal that obtains on the sampling capacitor is connected to the input end of voltage signal transducer, the voltage signal transducer is transformed into single-chip computer control system acceptable voltage signal with the ac voltage signal that samples, send the A/D passage 2 of single-chip computer control system and the input end of voltage transient amount start-up circuit respectively, the output terminal Yout of voltage transient amount start-up circuit connects interruption 1 pin of single-chip computer control system; Single-chip computer control system with the failure indicating circuit indication of result by joining with its mouthful 3.
The design proposes directly to measure the method for overhead transmission line voltage-to-ground, makes the differentiation of line-to-ground fault more direct reliable.
A kind of power distribution network line short and earth fault indicating device, its structural feature is: comprise current sensor, voltage sensor, the current signal transducer, the voltage signal transducer, current transients amount start-up circuit, voltage transient amount start-up circuit, single-chip computer control system, failure indicating circuit and power-supply circuit, current sensor, the current signal transducer, current transients amount start-up circuit, single-chip computer control system connects successively, voltage sensor, the voltage signal transducer, voltage transient amount start-up circuit, single-chip computer control system connects successively, current sense feel device, another output terminal of voltage sensor is connected with single-chip computer control system, and failure indicating circuit is connected with the monolithic control system.
Described current transients amount start-up circuit mainly is electrically connected to constitute by voltage comparator, resistance, electric capacity and forms.
Described voltage transient amount start-up circuit mainly is electrically connected by voltage comparator, resistance, electric capacity and constitutes.
Described power distribution network line short and earth fault indicating device, also comprise a kind of metal shell, described voltage sensor is connected with metal shell by sampling capacitor, the other end of electric capacity links to each other with aerial condutor, reference point is put in the some tipping that is connected in series of metal shell and electric capacity, between electric capacity and the pole line tie point voltage sensor output terminal is set.
Described current sensor is a CT type structure sensor.
Described CT type structure sensor is for to be made by permeability magnetic material, the loop R that described permeability magnetic material forms has winding around aerial condutor on R, two output terminals of winding link to each other respectively with the resistance two ends, terminating set reference point after the connection, the other end then are the output terminal of electric current flow sensor.
The invention has the beneficial effects as follows: compare with existing disclosed technology, this power distribution network line short and earth fault indicating device, owing to adopt the scheme of current transients amount and voltage transient amount start-up circuit, therefore can improve the performance factor of device, shorten trouble shooting time, thereby improve the power supply reliability of distribution network systems.The design proposes directly to measure the method for overhead transmission line voltage-to-ground, makes the differentiation of line-to-ground fault more direct reliable.
Description of drawings
Below with reference to the embodiment accompanying drawing the present invention is further described
Fig. 1 is a principle of work block scheme of the present invention
Fig. 2 starts structural representation for short trouble transients of the present invention
Fig. 3 starts structural representation for earth fault transients of the present invention
Fig. 4 voltage sensor structural representation
Fig. 5 current sensor structural representation
Embodiment
Below with reference to the embodiment accompanying drawing the present invention is further described
Among Fig. 1, C is that current sensor, V are that voltage sensor, X are that current signal transducer, Y are that voltage signal transducer, P are that current transients amount start-up circuit, N are voltage transient amount start-up circuit, M is a single-chip computer control system, and D is a failure indicating circuit, and S is a power-supply circuit.Its annexation is certain root lead that the magnetic circuit of CT type current sensor C surrounds electric distribution network overhead wire, the current signal of this lead of its secondary winding output is connected to the input end of current signal transducer X, current signal transducer X is transformed into single-chip computer control system M acceptable voltage signal with the current signal that samples, send the A/D passage 1 of single-chip computer control system M and the input end Vx of current transients amount start-up circuit P respectively, the output terminal Xout of current transients amount start-up circuit P connects interrupt INT 0 pin of single-chip computer control system M; Same lead of the sampling capacitor one termination electric distribution network overhead wire of voltage sensor V, another termination metal matter casing, form sampling capacitor and the casing series circuit of distributed capacitance over the ground, this lead voltage-to-ground signal that obtains on the sampling capacitor is connected to the input end of voltage signal transducer Y, voltage signal transducer Y is transformed into single-chip computer control system M acceptable voltage signal with the ac voltage signal that samples, send the A/D passage 2 of single-chip computer control system M and the input end Vy of voltage transient amount start-up circuit N respectively, the output terminal Yout of voltage transient amount start-up circuit N connects interrupt INT 1 pin of single-chip computer control system M; The mouth 3 of single-chip computer control system M meets failure indicating circuit D, and power-supply circuit S meets single-chip computer control system M, current signal transducer X, voltage signal transducer Y, current transients amount start-up circuit P, voltage transient amount start-up circuit N respectively.
Among Fig. 2, current transients amount start-up circuit P is by resistance R 1, R2, R3, R4, R5, capacitor C 1, voltage comparator U1 form, R1 and R2 series connection, R2 other end ground connection, series connection point V2 meets R5, the reverse input end of another termination of R5 U1, R3 and R4 series connection, the input end in the same way of another termination of R4 U1, series connection point V1 are through capacitor C 1 ground connection, and the input end Vx of current transients amount start-up circuit P links to each other with the non-series connection end of R3 with R1, the output terminal of U1 links to each other with the output terminal Xout of current transients amount start-up circuit P, the direct supply Vcc that U1 is provided by power-supply circuit S (+5V) power supply.
Among Fig. 3, voltage transient amount start-up circuit N is by resistance R 6, R7, R8, R9, R10, capacitor C 2, voltage comparator U2 forms, R6 and R7 series connection, series connection point is V4, R7 other end ground connection, R9 and R10 series connection, the reverse input end of another termination of R10 U2, series connection point V3 are through capacitor C 2 ground connection, and R9 is non-, and the series connection end links to each other with V4, the input end in the same way of R8 one termination U2, the other end of R8 links to each other with the input end Vy of voltage transient amount start-up circuit N and the non-series connection end of R6, and the output terminal of U2 links to each other with the output terminal Yout of voltage transient amount start-up circuit N, the direct supply Vcc that U2 is provided by power-supply circuit S (+5V) power supply.
Fig. 4 is voltage sensor V, by sampling capacitor C
SBe in series C with metal shell
SThe other end is connected with aerial condutor L, and metal shell distributed capacitance over the ground is C
0, series connection point S meets the device reference point of this indicator, V
OUTOutput terminal for voltage sensor.
Fig. 5 is current sensor C, and it is the sensor of CT type structure, and the loop R that permeability magnetic material is made surrounds aerial condutor L, winding N is arranged, N two output terminals and resistance R on the R
0Two ends link to each other respectively.Reference point is put in a tipping, and another contact then is the output terminal of current sensor.
Described failure indicating circuit is a kind of pilot lamp.
Described current signal transducer and voltage signal transducer are the translation circuit that a kind of AC signal is transformed to direct current signal, and it is to be the alternating current-direct current signal transformation circuit of core formation with the AD736 chip.
As can be seen from Figure 1, after single-chip computer control system M is interrupted wake-up, electric current, the voltage signal that current signal transducer X, voltage signal transducer Y are exported respectively exports A/D passage 1, the A/D passage 2 of single-chip computer control system M to, obtain the digital value of aerial condutor electric current and voltage-to-ground value thereof, carry out the algorithm of fault mode for single-chip computer control system M and differentiate.Compare with disclosed technology, the design proposes directly to measure the method for overhead transmission line voltage-to-ground, makes the differentiation of line-to-ground fault more direct reliable.
As can be seen from Figure 2, the Vx that represents the aerial condutor size of current is an input signal, if get R1=R2, then circuit moves V1＞V2 just often, and output Xout is a high level.If short circuit causes Vx to jump to kVx (k＞1), synchronization V2=0.5kVx, because the electric capacity both end voltage is not undergone mutation, therefore, the rising of V1 will lag behind V2, according to firstorder circuit total regression theory, the response of V1 can be represented with following formula:
τ=R in the formula (1)
3C
1Be the comparer time constant of input end RC circuit in the same way.When V2＞V1, U1 output Xout becomes low level, and up to V1＞V2, U1 output Xout recovers high level again, and one time the transients start-up course is finished.Being not difficult to release the Vx that causes U1 to overturn by Fig. 2 will skyrocket more than 1 times at least.
As can be seen from Figure 3, in normal operation, the output Yout of comparer U2 is a high level.If voltage signal Vy falls suddenly, the inverting input of U2 is because the existence of capacitor C 2, voltage V3 does not suddenly change, and input terminal voltage falls with Vy and causes V3＞Vy in the same way, make U2 output become low level, up to Vy＞V3, U2 output Yout recovers high level again, finishes primary voltage and falls the transients start-up course.That is, when U2 output sports low level by high level, mean that voltage signal falls.If get R6=R7, then Vy drops to less than original 1/2 o'clock, and U2 exports a negative edge.
The present invention is installed in the 10kV distribution line, owing to adopted technique scheme, can correctly indicate the short circuit and the earth fault of 10kV power distribution network circuit, will shorten the faulty equipment line walking and search the time, improves operational efficiency and power supply reliability.
The above only is specific embodiments of the invention, is not that the present invention is made restriction.All foundations technical spirit of the present invention still belongs in the protection domain of technical solution of the present invention any simple modification, change or equivalent transformation that above embodiment carries out.
Claims (8)
1, a kind of power distribution network line short and earth fault indicating means is characterized in that: described method is a kind of electric current, voltage transient amount start-up circuit method.
2, according to described power distribution network line short of claim 1 and earth fault indicating means, it is characterized in that: it is for surrounding the magnetic circuit of current sensor in certain root lead of electric distribution network overhead wire, the current signal of this lead of its secondary winding output is connected to the input end of current signal transducer, the current signal transducer is transformed into single-chip computer control system acceptable voltage signal with the current signal that samples, send the A/D passage of single-chip computer control system and the input end of current transients amount start-up circuit respectively, the output terminal Xout of current transients amount start-up circuit connects interruption 0 pin of single-chip computer control system; Same lead of the sampling capacitor one termination electric distribution network overhead wire of voltage sensor, another termination metal matter casing, form sampling capacitor and the casing series circuit of distributed capacitance over the ground, this lead voltage-to-ground signal that obtains on the sampling capacitor is connected to the input end of voltage signal transducer, the voltage signal transducer is transformed into single-chip computer control system acceptable voltage signal with the ac voltage signal that samples, send the A/D passage of single-chip computer control system and the input end Vy of voltage transient amount start-up circuit respectively, the output terminal Yout of voltage transient amount start-up circuit connects interruption 1 pin of single-chip computer control system; Single-chip computer control system with the failure indicating circuit indication of result by joining with its mouthful.
3, a kind of power distribution network line short and earth fault indicating device, it is characterized in that: comprise current sensor, voltage sensor, the current signal transducer, the voltage signal transducer, current transients amount start-up circuit, voltage transient amount start-up circuit, single-chip computer control system, failure indicating circuit and power-supply circuit, current sensor, the current signal transducer, current transients amount start-up circuit, single-chip computer control system connects successively, voltage sensor, the voltage signal transducer, voltage transient amount start-up circuit, single-chip computer control system connects successively, current sense feel device, another output terminal of voltage sensor is connected with single-chip computer control system, and failure indicating circuit is connected with the monolithic control system.
4, power distribution network line short according to claim 3 and earth fault indicating device is characterized in that: described current transients amount start-up circuit mainly is electrically connected to constitute by voltage comparator, resistance, electric capacity and forms.
5, according to claim 3 or 4 described power distribution network line short and earth fault indicating devices, it is characterized in that: described voltage transient amount start-up circuit mainly is electrically connected by voltage comparator, resistance, electric capacity and constitutes.
6, power distribution network line short according to claim 5 and earth fault indicating device, it is characterized in that: described power distribution network line short and earth fault indicating device, also comprise a kind of metal shell, described voltage sensor is connected with metal shell by sampling capacitor, the other end of electric capacity links to each other with aerial condutor, reference point is put in the some tipping that is connected in series of metal shell and electric capacity, between electric capacity and the pole line tie point voltage sensor output terminal is set.
7, power distribution network line short according to claim 6 and earth fault indicating device is characterized in that: described current sensor is a CT type structure sensor.
8, power distribution network line short according to claim 7 and earth fault indicating device, it is characterized in that: described CT type structure sensor is for to be made by permeability magnetic material, the loop R that described permeability magnetic material forms is around aerial condutor L, winding is arranged on R, two output terminals of winding link to each other respectively with the resistance two ends, terminating set reference point after the connection, the other end then are the output terminal of electric current flow sensor.
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| Application Number | Priority Date | Filing Date | Title |
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| CNA2008100714222A CN101320070A (en) | 2008-07-21 | 2008-07-21 | Indication method and device of short circuit and ground fault of power distribution network |
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| CNA2008100714222A CN101320070A (en) | 2008-07-21 | 2008-07-21 | Indication method and device of short circuit and ground fault of power distribution network |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102288866A (en) * | 2011-07-25 | 2011-12-21 | 北京瑞科思创科技有限公司 | Method and equipment for detecting single-phase earth fault of transmission and distribution line |
| CN102288865A (en) * | 2011-07-22 | 2011-12-21 | 北京瑞科思创科技有限公司 | Method and equipment for detecting short-circuit earth fault of transmission and distribution line |
| CN102944804A (en) * | 2012-11-13 | 2013-02-27 | 航天科工深圳（集团）有限公司 | Overhead line fault detection system |
| CN102998596A (en) * | 2012-12-20 | 2013-03-27 | 诸暨市供电局 | System for detecting faults of overhead line and detection method thereof |
| CN103412231A (en) * | 2013-07-09 | 2013-11-27 | 上海卫星工程研究所 | Distribution short circuit self checking device and method thereof |
| CN103518141A (en) * | 2011-04-05 | 2014-01-15 | 萨甘安全防护公司 | Method and system for detecting a short-circuit affecting a sensor |
| CN103558497A (en) * | 2013-11-15 | 2014-02-05 | 武汉大学 | Method and device for detecting state of ground lead of power transmission line in power distribution network |
| CN105137280A (en) * | 2015-08-01 | 2015-12-09 | 国家电网公司 | Fault warning device suitable for 10 kilovolt distribution line |
| CN106226651A (en) * | 2016-07-12 | 2016-12-14 | 国电南瑞科技股份有限公司 | A kind of overhead type indicating fault location terminal and voltage-to-ground measuring method |
| CN107255770A (en) * | 2017-05-12 | 2017-10-17 | 广东电网有限责任公司东莞供电局 | Cable overhead line hybrid distributed feeder system |
| CN108572279A (en) * | 2018-05-30 | 2018-09-25 | 广东电网有限责任公司 | A kind of electric distribution network overhead wire operation impedance synchronous measuring apparatus |
| CN111859609A (en) * | 2020-06-02 | 2020-10-30 | 武汉船用电力推进装置研究所（中国船舶重工集团公司第七一二研究所） | MATLAB/SIMULINK-based fuse modeling simulation method |
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| CN103518141B (en) * | 2011-04-05 | 2016-09-14 | 萨甘安全防护公司 | For detecting the method and system of the short circuit affecting sensor |
| CN103518141A (en) * | 2011-04-05 | 2014-01-15 | 萨甘安全防护公司 | Method and system for detecting a short-circuit affecting a sensor |
| CN102288865A (en) * | 2011-07-22 | 2011-12-21 | 北京瑞科思创科技有限公司 | Method and equipment for detecting short-circuit earth fault of transmission and distribution line |
| CN102288865B (en) * | 2011-07-22 | 2014-01-22 | 北京瑞科思创科技有限公司 | Method and equipment for detecting short-circuit earth fault of transmission and distribution line |
| CN102288866B (en) * | 2011-07-25 | 2014-07-30 | 何晋章 | Method and equipment for detecting single-phase earth fault of transmission and distribution line |
| CN102288866A (en) * | 2011-07-25 | 2011-12-21 | 北京瑞科思创科技有限公司 | Method and equipment for detecting single-phase earth fault of transmission and distribution line |
| CN102944804A (en) * | 2012-11-13 | 2013-02-27 | 航天科工深圳（集团）有限公司 | Overhead line fault detection system |
| CN102998596A (en) * | 2012-12-20 | 2013-03-27 | 诸暨市供电局 | System for detecting faults of overhead line and detection method thereof |
| CN103412231A (en) * | 2013-07-09 | 2013-11-27 | 上海卫星工程研究所 | Distribution short circuit self checking device and method thereof |
| CN103412231B (en) * | 2013-07-09 | 2015-11-18 | 上海卫星工程研究所 | Distribution short circuit self-checking unit and method |
| CN103558497A (en) * | 2013-11-15 | 2014-02-05 | 武汉大学 | Method and device for detecting state of ground lead of power transmission line in power distribution network |
| CN103558497B (en) * | 2013-11-15 | 2016-04-27 | 武汉大学 | For state of earth wire detection method and the device of transmission line of electricity in power distribution network |
| CN105137280A (en) * | 2015-08-01 | 2015-12-09 | 国家电网公司 | Fault warning device suitable for 10 kilovolt distribution line |
| CN106226651A (en) * | 2016-07-12 | 2016-12-14 | 国电南瑞科技股份有限公司 | A kind of overhead type indicating fault location terminal and voltage-to-ground measuring method |
| WO2018010369A1 (en) * | 2016-07-12 | 2018-01-18 | 国电南瑞科技股份有限公司 | Overhead-type fault indication positioning terminal and method for measuring voltage to ground |
| CN106226651B (en) * | 2016-07-12 | 2019-08-23 | 国电南瑞科技股份有限公司 | A kind of overhead type indicating fault positioning terminal and voltage-to-ground measurement method |
| CN107255770A (en) * | 2017-05-12 | 2017-10-17 | 广东电网有限责任公司东莞供电局 | Cable overhead line hybrid distributed feeder system |
| CN108572279A (en) * | 2018-05-30 | 2018-09-25 | 广东电网有限责任公司 | A kind of electric distribution network overhead wire operation impedance synchronous measuring apparatus |
| CN111859609A (en) * | 2020-06-02 | 2020-10-30 | 武汉船用电力推进装置研究所（中国船舶重工集团公司第七一二研究所） | MATLAB/SIMULINK-based fuse modeling simulation method |
| CN111859609B (en) * | 2020-06-02 | 2022-04-12 | 武汉船用电力推进装置研究所（中国船舶重工集团公司第七一二研究所） | MATLAB/SIMULINK-based fuse modeling simulation method |
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