CN102279344A - Intelligent state sensor for distribution line - Google Patents
Intelligent state sensor for distribution line Download PDFInfo
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- CN102279344A CN102279344A CN2010101979317A CN201010197931A CN102279344A CN 102279344 A CN102279344 A CN 102279344A CN 2010101979317 A CN2010101979317 A CN 2010101979317A CN 201010197931 A CN201010197931 A CN 201010197931A CN 102279344 A CN102279344 A CN 102279344A
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Abstract
The invention discloses an intelligent state sensor for a distribution line. The intelligent state sensor comprises a direct-current high-voltage power supply (1), a switch module (2), a signal acquisition module (3) and a protective resistor R0 (4), wherein when the distribution line runs normally, the intelligent state sensor for the distribution line is in insulating dormancy state; when the line trips, the switch module (2) receives a conducting signal transmitted by a computer system, the intelligent state sensor for the distribution line is started for detecting a state signal of the failed line, and the signal is transmitted to the computer system for corresponding data processing by using the single acquisition module (3), so that intelligent fault diagnosis of the distribution line is realized; and after signal acquisition is finished, the switch module (2) receives a switch-off signal transmitted by the computer system, so that the intelligent state sensor for the distribution line stops running. The intelligent state sensor has the advantages of simple and compact structure, high reliability, quick startup, capability of realizing real-time accuracy acquisition and tracking of signals, and the like.
Description
Technical field
The present invention is mainly concerned with the fault diagnosis field of distribution line, refer in particular to a kind of distribution line condition intelligent sensor, be used for the distribution line status signal that breaks down is gathered in real time and followed the tracks of, and be used, to realize the intelligent diagnostics of distribution line failure with computer system.
Background technology
Power distribution network is the network that directly distributes electric energy to vast power consumer, thereby the safety of power distribution network and power supply reliability more and more come into one's own, but the power distribution network of China is because historical reasons, also very backward, in network structure, technical management and operation maintenance, also have a lot of defectives, to such an extent as to distribution network failure frequently takes place, especially thunder and lightning, pollution, internal overvoltage effect etc. all when multifactor distribution network failure frequent especially, greatly influenced the people's production, household electricity.In the electrical network of this electric pressure, distribution line tripping operation accident often takes place, greatly influenced power supply reliability and power grid security.Distribution line breaks down generally two kinds: a kind of is transient fault; Another kind is a permanent fault.
At present, auto recloser puts into operation in distribution line, can effectively reduce the power outage that transient fault causes in the distribution line, and can get rid of rapidly because of transient fault causes power outage, be very tangible for the effect of the power supply reliability that improves distribution line.But in case permanent fault occurs, automatic reclosing puts into operation this moment, not only can not excise fault, and fault coverage is further enlarged, the electric system meeting suffers the impact of short-circuit current once more on the one hand, and may cause to overlap the increase of back electric system rocking tendency, even may make the electric system loss of stability; Relay protection makes isolating switch disconnect once more on the other hand, and the double at short notice cutting-off of short-circuit electric current of isolating switch has worsened its condition of work, has shortened the serviceable life of isolating switch, sometimes even can cause circuit breaker explosion.Therefore, be necessary the line fault situation is detected automatically, distinguish fault type, automatic reclosing thereby whether decision puts into operation; And can the key of failure judgement type be and gather effectively the status signal of faulty line.
The collection of signal is generally finished by sensor.Sensor is to carry out the visual plant that electric energy metrical, measurement, control protection etc. provide current and voltage signals for electric system, and safe, the stable and economical operation of its precision and reliability and electric system is closely related, is the electric system imperative equipment.Along with the continuous development of electronic technology, computer technology, mechanics of communication, network technology and people to improving constantly that power supply quality requires, the voltage in the transmission and distribution networks, the monitoring technology of electric current are also brought in constant renewal in.
At present, the monitoring of the POWER SYSTEM STATE of widespread use mainly is traditional electromagnetic sensor.Traditional electromagnetic sensor adopts electromagnetic induction principle, the big current conversion of a winding is become the little electric current of Secondary Winding.Though this current transformer applied range, the operating experience technology maturation, but it has magnetic saturation, ferroresonance, dynamic range is little, frequency band is narrow, insulation system is complicated day by day, volume is big, cost is high, and oil-filled equipment exists the shortcomings such as problem of explosive and difficult maintenance, is difficult to satisfy the requirement of power system development.
Except traditional electromagnetic sensor, electronic sensor and the photoelectric sensor that also occurs also begins to be applied in the middle of the electric system recently, is subjected to extensive concern and research in the power system monitoring field.
Electronic sensor mainly is to utilize Faraday effect, magnetostrictive effect, Kerr effect and contrary piezomagnetic effect etc.For traditional electromagnetic sensor, it can remedy the defective of some traditional electromagnetic sensors.But because its structure technology is complicated, the cost height, performance is difficult for accomplishing to stablize, and practicalization slowly can not be widely used.
Electro-optical pickoff is based on faraday (Faraday) magneto-optic effect, measurement ring is around the magnetic field intensity line integral of electric current, and Faraday magnetooptical effect is meant that linearly polarized light its plane of polarization under the effect of current field will rotate one with the principle design of effectively light path and the proportional angle of magnetic field intensity.Electro-optical pickoff has certain superiority at more traditional electric sensor aspect degree of accuracy and the anti-electromagnetic interference (EMI); In photoelectric sensor, high-pressure side information is to be transferred to electronegative potential by the glass optical fiber of being made by insulating material, and photoelectric sensor does not contain iron core, has eliminated problems such as magnetic saturation, ferroresonance.Only exist optical fiber to get in touch between the high pressure of photoelectric sensor and the low pressure, the danger that low-pressure side does not produce because of open circuit or short circuit because there is not magnetic coupling, has been eliminated electromagnetic interference (EMI) to the mutual inductor Effect on Performance simultaneously.But it needs the conversion between the photosignal, and the principle complexity, and structure is meticulous, and technology is not mature enough, and operation stability is poor, and serviceable life is short, the price height, and the scope of application is little.
In addition, at present in the method for discrimination at distribution line transient fault and permanent fault, owing to there is not a kind of well behaved line status sensor that line state signal is carried out in real time, gathers accurately and follows the tracks of, the judged result error is big, confidence level is not high and cause.At present transient fault and permanent failure judgement principle have 3 kinds, promptly based on the fault recovery voltage characteristic, based on the fault electric arc characteristic and based on the hf channel signal transmission characteristics.Based on recovery voltage in the fault recovery voltage characteristic method still less than 10% of circuit rated voltage, and for the circuit of band shunt reactor, because shunt reactor is to the compensating action of line distribution capacitance, it is less that fault disconnects phase recovery voltage amplitude, the line side voltage transformer (VT) is got this voltage and is had bigger error, and there is the low-frequency oscillation component in transient fault, and these have directly influenced the effective application based on recovery voltage characteristic method of discrimination.Based on the method for transient fault arc characteristic then because of 5% of the general not enough circuit rated voltage of arc voltage, thereby the problem that in measuring, analyze and judging, has confidence level, the influence that is subjected to electric arc blow-out process, transient signal to obtain precision and malfunction simultaneously is difficult to practicability.Method based on the hf channel rate of signal attenuation is subjected to factor affecting such as line length and weather, and can't use for the circuit that does not adopt high-frequency communication.
Summary of the invention
The present invention is directed to the shortcoming of above-mentioned prior art, provide a kind of simple and compact for structure, good reliability, device to start rapidly, can realize the distribution line condition intelligent sensor that signal is accurately gathered and followed the tracks of in real time.
The technical solution used in the present invention is: a kind of distribution line condition intelligent sensor, and when distribution line normally moved, distribution line condition intelligent sensor was in the insulation dormant state, can bear the normal voltage and the superpotential of electrical network; When the tripping operation fault takes place in distribution line, startup distribution line condition intelligent sensor detects the status signal of faulty line, be distribution line condition intelligent sensor with fault mutually insulation resistance Rm constitute the impedance loop, gather the voltage signal at sampling resistor Ri two ends in the impedance loop, and transmit the signal to the computer system that is used with it and carry out corresponding data processing.It comprises DC high-voltage power supply, switch module, signal acquisition module and protective resistance R0; Described DC high-voltage power supply; switch module; signal acquisition module and protective resistance R0 are composed in series distribution line condition intelligent sensor successively; when line failure; with fault mutually insulation resistance Rm constitute the impedance loop; described DC high-voltage power supply provides DC voltage for the impedance loop; described switch module is used for conducting or the cut-off signals that the receiving computer system sends; whether control distribution line condition intelligent sensor starts; described signal acquisition module is used to gather the status signal of faulty line; described protective resistance R0 is serially connected in the effect of playing current limliting in the loop, prevents that other elements are damaged owing to electric current is excessive.
As a further improvement on the present invention:
Described switch module is made up of IGBT trigger circuit, IGBT series circuit and equalizer circuit; Conducting or cut-off signals that described IGBT trigger circuit send by the receiving computer system, the conducting or the shutoff of control IGBT series circuit, described IGBT series circuit is in series by a plurality of identical IGBT, can bear the normal voltage and the superpotential of electrical network during off state, be low resistive state during conducting, described equalizer circuit is used to guarantee that the IGBT series circuit keeps in balance to the superpotential of each IGBT at shutdown moment;
Described signal acquisition module is made up of sampling resistor Ri and amplifying circuit; When line failure, the switch module conducting, voltage signal to sampling resistor Ri two ends is gathered, the signal that described amplifying circuit is used for collecting from sampling resistor Ri two ends amplifies, convert thereof into and satisfy the signal that computer system processor requires, send into computer system again and handle.
The present invention has following advantage:
Distribution line condition intelligent sensor of the present invention, can realize the insulation and the insulation recovery state of distribution line that the tripping operation fault takes place are carried out real-time detection and tracking, and be used with computer system thereof, with automatic judgement line fault type, differentiate and whether can drop into automatic reclosing, thereby guarantee that power system security effectively moves, guarantee the safety of the people's lies and property to have good using value.The present invention utilizes IGBT to constitute switch module, is used to enable or withdraw from intelligence sensor, and its conducting is controlled by computer system thereof with shutoff, has realized intellectualized operation; And the conducting of IGBT is rapid with shutoff, and the line state signal that collects has real-time and accuracy.That the present invention has is simple and compact for structure, good reliability, device start rapidly, can realize advantages such as accurately gathering in real time of signal and tracking.
Description of drawings
Fig. 1 is the framed structure synoptic diagram of apparatus of the present invention;
Fig. 2 is the circuit theory synoptic diagram of switch module in the embodiment of the invention;
Fig. 3 is the circuit theory synoptic diagram of IGBT trigger circuit in the embodiment of the invention;
Fig. 4 is the circuit theory synoptic diagram of equalizer circuit in the embodiment of the invention;
Fig. 5 is the circuit theory synoptic diagram of amplifying circuit in the embodiment of the invention.
Embodiment
As shown in Figure 1, distribution line condition intelligent sensor of the present invention comprises DC high-voltage power supply 1, switch module 2, signal acquisition module 3 and protective resistance R04; DC high-voltage power supply 1, switch module 2, signal acquisition module 3 and protective resistance R04 are composed in series distribution line condition intelligent sensor successively, when circuit normally moves, distribution line condition intelligent sensor is in the insulation dormant state, can bear the normal voltage and the superpotential of electrical network; When line failure; with fault mutually insulation resistance Rm constitute the impedance loop; DC high-voltage power supply 1 provides DC voltage for the impedance loop; switch module 2 is used for conducting or the cut-off signals that the receiving computer system sends; whether control distribution line condition intelligent sensor starts; signal acquisition module 3 is used to gather the status signal of faulty line, and protective resistance R04 is serially connected in the effect of playing current limliting in the loop, prevents that other elements are damaged owing to electric current is excessive.Switch module 2 is made up of IGBT trigger circuit 21, IGBT series circuit 22 and equalizer circuit 23; Signal acquisition module 3 is made up of amplifying circuit 31 and sampling resistor Ri32.
As shown in Figure 2, switch module 2 is made up of IGBT trigger circuit 21, IGBT series circuit 22 and equalizer circuit 23.Conducting or cut-off signals that IGBT trigger circuit 21 send by the receiving computer system, the conducting or the shutoff of control IGBT series circuit 22; IGBT series circuit 22 is in series by a plurality of identical IGBT, to satisfy the higher voltage value, can bear the normal voltage and the superpotential of electrical network during off state, is low resistive state during conducting; Equalizer circuit 23 is used to guarantee that the IGBT series circuit keeps in balance to the superpotential of each IGBT at shutdown moment.
The IGBT trigger circuit 21 of Fig. 3 for constituting by integrated circuit TLP250.The isolation voltage height of the built-in optocoupler of TLP250, rising and fall time are little, can drive IGBT effectively.When input control signal, transistor V4 conducting input+15V driving voltage; When control signal was zero, transistor V5 conducting input-10V driving voltage ended IGBT.The driver volume that TLP250 constitutes is little, and low price is not to be with comparatively ideal selection in the IGBT driver of overcurrent protection.
Fig. 4 is an IGBT equalizer circuit 23.It is the superpotential of each IGBT to be kept in balance in conducting or shutdown moment in order to guarantee that the IGBT cascade system is carried out the purpose of all pressing, to prevent to damage the inner structure of IGBT.Require in this equalizer circuit capacitor C 1＞＞C2, resistance R 1＞＞R2.When static, the VT1 drain-source utmost point is by R1, and the resistance after the R2 series connection is determined its voltage quiescent value, and R1 plays main minute compression functions.As long as R1+R2=R3+R4=...=Rn-1+Rn can guarantee the static state voltage equipoise between the IGBT.It all presses principle to be:
1) when VT1 does not open, R1, R2 carries out static state voltage equipoise to VT1, because R1＞＞R2, the most of voltage of quiescent voltage concentrates on the R1 two ends;
2) when VT1 opens fully, because C1＞＞C2, C1 is a DC source with respect to C2, C1 carries out anti-phase charging by VT1 to C2.The electric weight of C1 and both end voltage U thereof
C1Substantially remain unchanged C2 both end voltage U
C2=-U
C1, the gate pole of VT1 is a noble potential, diode VD1 ends in the other direction, and drive signal and feedback channel are isolated;
3) when VT1 begins to turn-off, the electric current by VT1 is reduced to zero gradually, and circuit is charged to C2 by C1, U
C2From-U
C1Increase to positive polarity gradually, at this moment VT1 both end voltage U
Vn=U
C1+ U
C2
4) when turn-offing because of certain reason, VT1 drain-source utmost point two ends produce superpotential.Main circuit is to C1 and C2 charging.Because of C1＞＞C2, U
C1Constant, and U
C2For just and rise very soon, the VT1 gate pole is an electronegative potential when turn-offing, and positive trigger pip of VT1 gate pole is given in the VD1 conducting, makes VT1 open-minded, and the superpotential at its two ends disappears, U
C2Current potential when getting back to VT1 static state dividing potential drop again;
5) when VT1 does not open fully, for a certain reason, produce superpotential at the VT1 two ends, the current potential of same C2 top crown can very fast rising, makes the VD1 conducting, produces positive voltage signal, quicken the open-minded of VT1, thereby suppress the superpotential at VT1 drain-source utmost point two ends effectively.
By the analytical work principle as can be known, this circuit need not to add the absorption circuit again.Since R1, R2＞＞load RL, so R1, the power that R2 consumes is very little, thereby has improved efficient.Owing to introduced feedback channel, the response of switch is accelerated, thereby has suppressed the superpotential of IGBT series connection.
Fig. 5 is an amplifying circuit 31.When line failure, switch module 2 conductings, voltage signal to sampling resistor Ri32 two ends is gathered, because the signal that collects from sampling resistor Ri32 two ends possibly can't satisfy the data processing requirement of computer system, need it to be amplified, send into computer system again and handle by signal amplification circuit 31.As shown in Figure 5, voltage signal U
vFrom the input of resistance R 8 ends,, and adopt negative feedback to amplify the voltage U of output through integrated operational amplifier output
0Magnification ratio is determined by Rf, R9.Output with the relational expression of input is:
Claims (5)
1. distribution line condition intelligent sensor, it is characterized in that: when distribution line normally moved, distribution line condition intelligent sensor was in the insulation dormant state, can bear the normal voltage and the superpotential of electrical network; When the tripping operation fault takes place in distribution line, startup distribution line condition intelligent sensor detects the status signal of faulty line, be distribution line condition intelligent sensor with fault mutually insulation resistance Rm constitute the impedance loop, gather the voltage signal at sampling resistor Ri two ends in the impedance loop, and transmit the signal to the computer system that is used with it and carry out corresponding data processing.
2. distribution line condition intelligent sensor according to claim 1 is characterized in that: it comprises DC high-voltage power supply (1), switch module (2), signal acquisition module (3) and protective resistance R0 (4); Described DC high-voltage power supply (1), switch module (2), signal acquisition module (3) and protective resistance R0 (4) are composed in series distribution line condition intelligent sensor successively, when line failure, with fault mutually insulation resistance Rm constitute the impedance loop.
3. distribution line condition intelligent sensor according to claim 2; described DC high-voltage power supply (1) provides DC voltage for the impedance loop; described switch module (2) is used for conducting or the cut-off signals that the receiving computer system sends; whether control distribution line condition intelligent sensor starts; described signal acquisition module (3) is used to gather the status signal of faulty line; described protective resistance R0 (4) is serially connected in the effect of playing current limliting in the loop, prevents that other elements are damaged owing to electric current is excessive.
4. according to claim 2 or 3 described distribution line condition intelligent sensors, it is characterized in that: described switch module (2) is made up of IGBT (insulated gate bipolar transistor) trigger circuit (21), IGBT series circuit (22) and equalizer circuit (23); Conducting or cut-off signals that described IGBT trigger circuit (21) send by the receiving computer system, the conducting or the shutoff of control IGBT series circuit (22), described IGBT series circuit (23) is in series by a plurality of identical IGBT, can bear the normal voltage and the superpotential of electrical network during off state, be low resistive state during conducting, described equalizer circuit (23) is used to guarantee that IGBT series circuit (22) keeps in balance to the superpotential of each IGBT at shutdown moment.
5. according to claim 2 or 3 described distribution line condition intelligent sensors, it is characterized in that: described signal acquisition module (3) is made up of amplifying circuit (31) and sampling resistor Ri (32); When line failure, switch module (2) conducting, voltage signal to sampling resistor Ri (31) two ends is gathered, the signal that described amplifying circuit (32) is used for collecting from sampling resistor Ri (31) two ends amplifies, convert thereof into and satisfy the signal that computer system processor requires, send into computer system again and handle.
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| CN2010101979317A CN102279344A (en) | 2010-06-11 | 2010-06-11 | Intelligent state sensor for distribution line |
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| CN2010101979317A CN102279344A (en) | 2010-06-11 | 2010-06-11 | Intelligent state sensor for distribution line |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103513095A (en) * | 2013-10-14 | 2014-01-15 | 国家电网公司 | Data acquisition device applied to power distribution line fault indicator detection |
| CN103592537A (en) * | 2013-10-31 | 2014-02-19 | 李景禄 | Electric line fault alternating-current impedance fast tracking and judging method |
| CN106646125A (en) * | 2016-12-09 | 2017-05-10 | 云南电力试验研究院(集团)有限公司 | Low-power-consumption power distribution network fault monitoring terminal |
| CN112187231A (en) * | 2020-08-04 | 2021-01-05 | 青岛鼎信通讯股份有限公司 | IGBT series gate terminal voltage-sharing circuit for line variation relation recognition |
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| CN101696983A (en) * | 2009-10-23 | 2010-04-21 | 李景禄 | Method and device for measuring neutral point of capacitance current of distribution network |
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| JPH04145829A (en) * | 1990-10-04 | 1992-05-19 | Yaskawa Electric Corp | Detector for fault section of distribution line |
| CN2116990U (en) * | 1992-02-21 | 1992-09-23 | 海安县自动控制设备厂 | High voltage dc power source |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103513095A (en) * | 2013-10-14 | 2014-01-15 | 国家电网公司 | Data acquisition device applied to power distribution line fault indicator detection |
| CN103513095B (en) * | 2013-10-14 | 2016-01-20 | 国家电网公司 | A kind of distribution line failure pointer detection data collector |
| CN103592537A (en) * | 2013-10-31 | 2014-02-19 | 李景禄 | Electric line fault alternating-current impedance fast tracking and judging method |
| CN103592537B (en) * | 2013-10-31 | 2016-03-02 | 李景禄 | Electric line fault AC impedance follows the tracks of determining method fast |
| CN106646125A (en) * | 2016-12-09 | 2017-05-10 | 云南电力试验研究院(集团)有限公司 | Low-power-consumption power distribution network fault monitoring terminal |
| CN112187231A (en) * | 2020-08-04 | 2021-01-05 | 青岛鼎信通讯股份有限公司 | IGBT series gate terminal voltage-sharing circuit for line variation relation recognition |
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Application publication date: 20111214 |