CN101881803B - Fault localization method of overhead transmission line - Google Patents
Fault localization method of overhead transmission line Download PDFInfo
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- CN101881803B CN101881803B CN2010101893034A CN201010189303A CN101881803B CN 101881803 B CN101881803 B CN 101881803B CN 2010101893034 A CN2010101893034 A CN 2010101893034A CN 201010189303 A CN201010189303 A CN 201010189303A CN 101881803 B CN101881803 B CN 101881803B
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Abstract
The invention discloses a fault localization method of an overhead transmission line, and the method comprises the following steps: dividing each phase of power transmission conducting wire of the overhead transmission line into a plurality of sections, and sequentially measuring line current phases at two end points of each section; and comparing the line current phases of the adjacent two end points, and determining the position of a fault point according to the comparison result. The fault localization method can judge the fault position by utilizing the situation that the line current phases of the conducting wires at two ends of the fault point change when a fault exists in the overhead transmission line, thereby greatly reducing the deviation of fault localization.
Description
Technical field
The present invention relates to field of power, relate more specifically to a kind of fault localization method of overhead transmission line.
Background technology
Along with power system development, electric system overhead transmission line electric pressure and transmission capacity are all progressively improving, and the accurate location technology of the fault of overhead transmission line is also more and more paid attention to by people.The accurate location of fault can help the electric system staff to find abort situation accurately and rapidly, and this guarantees that for reliably power supply of timely reparation circuit, recovery the safety and stability and the economical operation of electric system all has crucial effect.The accurate location of how to realize the overhead transmission line trouble spot quickly and accurately is an important subject of electric system.
Electric system overhead transmission line localization of fault has more following fault distance-finding methods and device at present.The first kind: with the measuring circuit impedance is target Detection.The impedance method range finding that specifically has failure wave-recording method, pulse reflection method and electronic circuit to constitute.Second type: reactance method.It is that a kind of false voltage and electric current of utilizing calculates the fault loop reactance value, thereby calibrates the method for fault distance.The 3rd type: traveling wave method.It is voltage, current traveling wave travel-time on the line when measuring fault, utilizes the mistiming between the wave head to calculate fault distance.More than all methods all have a problem: that is exactly that deviation for failure locating is big.
Summary of the invention
The present invention provides a kind of fault localization method of overhead transmission line.Can overcome defective of the prior art based on the present invention, reduce the deviation of localization of fault.
The invention discloses a kind of fault localization method of overhead transmission line, comprise the steps: measuring process, each phase transmission pressure of overhead transmission line is divided into multistage, measure the line current phase place at two end points places of each section successively; Step is confirmed in the trouble spot, compares the line current phase place of adjacent both ends point, according to comparative result, and the position of the localization of faults.
Above-mentioned fault localization method of overhead transmission line, preferred said trouble spot confirms that step further is: whether the line current phase place of judging said adjacent both ends point is in given in advance threshold range, if do not have the trouble spot between then said adjacent both ends point; If not, then, there is the trouble spot between said adjacent both ends point.
Above-mentioned fault localization method of overhead transmission line, preferred said Fault Locating Method realizes that based on fault location system said fault location system comprises base station M
0With a plurality of current phase pick-up units, said each current phase pick-up unit is arranged on each phase transmission pressure of overhead transmission line line pole tower; Said measuring process is specially: said base station M
0Send phase detection signal; The first current phase pick-up unit M
1Receive said phase-detection command signal, detect and obtain the said first current phase pick-up unit M
1Locate current transmission line of electricity current phase value, and said phase-detection command signal, said current transmission line of electricity current phase value are sent to the second the most contiguous current phase pick-up unit M
2The second current phase pick-up unit M
2Receive said phase-detection command signal and said current transmission line of electricity current phase value, obtain the second current phase pick-up unit M
2Locate current transmission line of electricity current phase value,
Above-mentioned fault localization method of overhead transmission line, preferred said trouble spot confirms that step is specially: the said second current phase pick-up unit M
2With the said second current phase pick-up unit M that obtains
2Locate current transmission line of electricity current phase value and the said first current phase pick-up unit M
1Locating current transmission line of electricity current phase value compares: if gap is then confirmed the said first current phase pick-up unit M greater than given in advance threshold value between the two
1With the second current phase pick-up unit M
2Between have fault; Otherwise, do not have fault; The second current phase pick-up unit M
2Said comparative result is passed through the first current phase pick-up unit M
1Pass said base station M back
0And with said phase-detection command signal and the said second current phase pick-up unit M
2Locate current transmission line of electricity current phase value and be sent to the 3rd the most contiguous current phase pick-up unit M
3By that analogy, obtain the current phase at last current phase pick-up unit place and compare, comparative result is beamed back base station M with last current phase until completion
0Base station M
0According to receiving a plurality of said comparative results, confirm the trouble spot of said overhead transmission line.
Above-mentioned fault localization method of overhead transmission line, preferred said base station M
0, said current phase pick-up unit all includes Zigbee CC2530 chip.
The lead line current phase place at two ends, trouble spot changed the decision bits abort situation when the present invention utilized the overhead transmission line troubles inside the sample space, had reduced the deviation of localization of fault greatly.
Description of drawings
Fig. 1 is the flow chart of steps of fault localization method of overhead transmission line embodiment of the present invention;
Fig. 2 is a fundamental diagram of the present invention;
Fault location system (a phase) synoptic diagram that Fig. 3 adopts for the present invention;
Fig. 4 is a current phase pick-up unit block scheme of the present invention;
Fig. 5 is the circuit diagram of signal of the present invention and power unit;
Fig. 6 is current-voltage phase waveform figure;
Fig. 7 is the circuit diagram of CC2530 programming Control chip of the present invention;
Fig. 8 is the circuit diagram of radio frequency amplifier of the present invention;
Fig. 9 is base station M of the present invention
0Structured flowchart.
Embodiment
For make above-mentioned purpose of the present invention, feature and advantage can be more obviously understandable, below in conjunction with accompanying drawing and embodiment the present invention done further detailed explanation.
With reference to Fig. 1, Fig. 1 comprises the steps: for the flow chart of steps of fault localization method of overhead transmission line embodiment of the present invention
Step S1, base station M
0Send phase detection signal.
Step S2, the first current phase pick-up unit M
1Receive said phase-detection command signal, detect and obtain the said first current phase pick-up unit M
1Locate current transmission line of electricity current phase value, and said phase-detection command signal, said current transmission line of electricity current phase value are sent to the second the most contiguous current phase pick-up unit M
2
Step S3, the second current phase pick-up unit M
2Receive said phase-detection command signal and said current transmission line of electricity current phase value, obtain the second current phase pick-up unit M
2Locate current transmission line of electricity current phase value, and with the said first current phase pick-up unit M
1Locating current transmission line of electricity current phase value compares: if gap is then confirmed the said first current phase pick-up unit M greater than given in advance threshold value between the two
1With the second current phase pick-up unit M
2Between have fault; Otherwise, do not have fault.
Step S4, the second current phase pick-up unit M
2Said comparative result is passed through the first current phase pick-up unit M
1Pass said base station M back
0And with said phase-detection command signal and the said second current phase pick-up unit M
2Locate current transmission line of electricity current phase value and be sent to the 3rd the most contiguous current phase pick-up unit M
3By that analogy, obtain the current phase at last current phase pick-up unit place and compare, comparative result is beamed back base station M with last current phase until completion
0
Step S5, base station M
0According to receiving a plurality of said comparative results, confirm the trouble spot of said overhead transmission line.
Principle of work introduction of the present invention is following:
As shown in Figure 2, between A, B overhead transmission line L, be a, b, c three phase line.During normal the operation, in the every phase conductor of whole transmission line of electricity, line current is equal and opposite in direction everywhere, phase place identical (influence of transmission line of electricity capacitance current is little, can ignore).When f point failed because: (1) if A, B end all has equivalent power supply to exist, then the current phase of f both sides transmission line of electricity is different in the trouble spot; (2) if the A end has equivalent power supply to exist, the B end does not have equivalent power supply to exist, and then the A side has short-circuit current, and the B side does not have short-circuit current; (3) if the B end has equivalent power supply to exist, the A end does not have equivalent power supply to exist, and then the B side has short-circuit current, and the A side does not have short-circuit current.Generally speaking, when the transmission line of electricity failed because, short dot both sides current phase scarcely together.Rely on the variation of current phase in the transmission line of electricity, just can the accurate in locating short dot.
The transmission pressure of overhead transmission line is fixedly connected with shaft tower through insulator.Article one, overhead transmission line is supporting transmission pressure by many shaft towers and is constituting.Distance is greatly between 100-500m between the shaft tower of general overhead transmission line.Occur between certain 2 shaft tower as long as can accurately locate short trouble, just can find the trouble spot fast.
Be elaborated in the face of the present invention down.
As shown in Figure 3, whole overhead transmission line has n shaft tower, shaft tower be numbered 1,2,3...i, i+1...n.On each phase transmission pressure of each shaft tower, install a current phase pick-up unit additional, install 3n current phase pick-up unit altogether additional.
Be that example is explained mutually with a below.
The current phase pick-up unit of corresponding shaft tower 1,2,3...i, i+1...n is numbered M
1, M
2, M
3... M
i, M
I+1... M
nWhen a phase failed because, such as failed because, current phase pick-up unit M so between shaft tower i and shaft tower i+1
1, M
2, M
3... M
iIt is identical locating detected transmission line of electricity current phase, and M
iWith M
I+1It is different to locate detected transmission line of electricity current phase, and variation has taken place phase place.Utilize this variation of current phase just can confirm that short circuit occurs between shaft tower i and the shaft tower i+1.Use current phase pick-up unit M
1, M
2, M
3... M
i, M
I+1... M
n, the current phase change information of each current phase pick-up unit installation place is delivered to the monitoring equipment M that places transmission line of electricity L end
0(abbreviate base station M as
0, generally containing that end of equivalent power supply) on.On the M0 of base station, just can orient the position that short trouble takes place.
Equally, the Fault Locating Method and a of b, c phase are similar.
Zigbee is the synonym of IEEE 802.15.4 agreement.According to the technology of this agreement regulation is a kind of short distance, low-power consumption, self-organization and wireless communication technology cheaply.Such as using chip CC2530 (price of every chip block is approximately 2 dollars) to constitute a Zigbee network node, it coordinates to realize communication each other according to the 802.15.4 standard between thousands of Zigbee network nodes.These Zigbee network nodes only need energy seldom, through radiowave data are passed to another Zigbee network node from a Zigbee network node with the mode of relay.Each Zigbee network node not only itself can be used as monitored object, for example directly carries out data acquisition and monitoring with the current transformer that it connected, and other Zigbee network node of transfer passes the data information of coming automatically.Zigbee network node transmission range generally between 10～100m, after increasing the RF emissive power, also rises to 1～3km.Here the transmission range that refers to is the distance between adjacent node.Through the relay of inter-node communication, transmission range can be very far away.Unlicensed band 2.4GHz is used in Zigbee network service.That Zigbee can adopt is starlike, sheet and mesh network topology, and by a host node management plurality of sub node, maximum host nodes can be managed 254 node; Host node also can be formed the big net of 65000 nodes at most by the last layer network node control simultaneously.The current phase pick-up unit M that uses among the present invention
1, M
2, M
3... M
i, M
I+1... M
nAnd base station M
0Be made up of the Zigbee network node, the programming Control chip adopts CC2530.
Fig. 4 is the structured flowchart of current phase pick-up unit of the present invention.This current phase pick-up unit comprises signal and power circuit, CC2530 programming Control chip, MAX2247 radio frequency amplifier and antenna.
Signal and power circuit effect have 2 points, and the one, the phase place of the detection current in wire in the current phase pick-up unit place transmission line of electricity of installing, the 2nd, to whole current phase pick-up unit power supply is provided.
The CC2530 programming Control has constituted the core of Zigbee network node, and its effect is to control CC2530 emission and receive information through programming, and phase information is compared processing.
The effect of MAX2247 radio frequency amplifier section is to increase transmitting range with the emission information power amplification of CC2530 programming Control.The effect of antenna is emission and receives information.
With reference to Fig. 5, Fig. 5 is signal and power circuit synoptic diagram, comprising:
Power unit: transmission line of electricity primary side current
is sensed secondary side through current transformer TA; Induction current is that
is by commutation diode V1, V2, V3 and V4 full-wave rectification; Stabilivolt DW voltage stabilizing is 4V; D5 charges to capacitor C through isolating diode, constitutes the 3.3V power supply.
Signal section: through current transformer TA with the transmission line of electricity primary side current
Sense secondary side current
Connect photoelectrical coupler GD transmitting terminal through current-limiting resistance R1, obtain square-wave voltage V as shown in Figure 6 at the receiving end I/O of photoelectrical coupler GD mouth
I/OThis square-wave voltage V
I/OInclude the current phase information in the primary side transmission line wire in the signal.
Current transformer TA iron core adopts special annular core, and primary side passes iron core, and second siding ring is on iron core.The full annular iron core is divided into the two halves that can be stitched together, and installs at the scene with convenient.
With reference to Fig. 6, Fig. 6 is current-voltage phase waveform figure.
Among the figure, the primary side waveform of current transformer TA is not taken into account the phase differential of current transformer primary side current and secondary side current among the figure for
for the secondary side waveform of
current transformer TA.V
I/OVoltage square wave for the primary side current that obtains through conversion of signals.Include the current phase information in the primary side transmission line wire in this square wave voltage signal.
With reference to Fig. 7, Fig. 7 is the circuit diagram of CC2530 programming Control chip of the present invention.
In the drawings, the I/O port is the square-wave signal receiving port, and RFOUT is the radiofrequency signal transmit port.The square wave voltage signal V that will include the current phase information in this node (i) primary side transmission line wire
I/OGeneral purpose I/O the port that is input to CC2530 is (such as the P of 11 pin
1-0Mouthful).Through CC2530 is programmed and control; The square-wave signal of detected input is sent; Receive relatively for next node (i+1); Receive the square-wave signal that comes from a last node (i-1) emission simultaneously and compare, calculate the phase change situation of this node (i) and a last node (i-1) square-wave signal with the square-wave signal of this node (i).Specifically be to detect the current phase that this node (i node) locates and launch, accept for next node (i+1 node).Accept the current phase of a node (i-1) and compare with this node (i) current phase.If this node (i) is identical with a last node (i-1) current phase; Then emission information is that this node (i) numbering and phase place do not change code 1; Otherwise; If this node (i) is inequality with a last node (i-1) current phase, then emission information is this node (i) numbering and phase change code 0.
With reference to Fig. 8, Fig. 8 is the circuit diagram of radio frequency amplifier.Through port RFOUT with the radiofrequency signal of CC2530 chip output through MAX2247 and its external circuit with the power amplification of signal, launch through antenna, so that signal transmission distance reaches 1Km.
With reference to Fig. 9, Fig. 9 is base station M of the present invention
0Block scheme, among the figure, this 3 part mode of connection of CC2530, MAX2247 and antenna is similar with the wiring among Fig. 4, and the 3.3V power supply can directly obtain through the voltage stabilizing of civil power step-down rectifier.CC2530 is connected with computing machine through USART0 SPI serial communication mode, and the port of CC2530 is selected P0-2, P0-3, P0-4 and P0-5.Through the computer programming deal with data, demonstrate the transmission line of electricity current phase situation of change at each shaft tower place on computers, thus the fault location point.
The current phase pick-up unit is because the dispersiveness of the Current Transformer TA of institute device primary side and secondary side phase differential parameter; Communication delay between used photoelectrical coupler GD parameter dispersed and two nodes; Even will inevitably cause adjacent two internodal phase data also to have certain gap once surveying under the complete same-phase of electric current; So when programming is judged, between adjacent two nodes, set a falling phase error δ.For the phase differential of both sides, trouble spot current phase, this error is minimum.If the phase error of adjacent node is littler than δ, just think these two node same-phases.Otherwise, just think that variation has taken place these two node phase places.
More than a kind of fault localization method of overhead transmission line provided by the present invention is described in detail; Used specific embodiment herein principle of the present invention and embodiment are set forth, the explanation of above embodiment just is used for helping to understand system of the present invention and core concept thereof; Simultaneously, for one of ordinary skill in the art, according to thought of the present invention, part in specific embodiments and applications all can change.In sum, this description should not be construed as limitation of the present invention.
Claims (2)
1. a fault localization method of overhead transmission line is characterized in that, comprises the steps:
Measuring process is divided into multistage with each phase transmission pressure of overhead transmission line, measures the line current phase place at two end points places of each section successively;
Step is confirmed in the trouble spot, compares the line current phase place of adjacent both ends point, according to comparative result, and the position of the localization of faults;
Said trouble spot confirms that step further is:
Whether the line current phase differential of judging said adjacent both ends point is in given in advance threshold range, if do not have the trouble spot between then said adjacent both ends point; If not, then, there is the trouble spot between said adjacent both ends point;
Said Fault Locating Method realizes that based on fault location system said fault location system comprises base station M
0With a plurality of current phase pick-up units, said current phase pick-up unit is arranged on each phase transmission pressure of each overhead transmission line line pole tower; Said measuring process is specially:
Said base station M
0Send the phase-detection command signal;
The first current phase pick-up unit M
1Receive said phase-detection command signal, detect and obtain the said first current phase pick-up unit M
1Locate current transmission line of electricity current phase value, and said phase-detection command signal, said current transmission line of electricity current phase value are sent to the second the most contiguous current phase pick-up unit M
2The second current phase pick-up unit M
2Receive said phase-detection command signal and said current transmission line of electricity current phase value, obtain the second current phase pick-up unit M
2Locate current transmission line of electricity current phase value;
Said trouble spot confirms that step is specially:
The said second current phase pick-up unit M
2With the said second current phase pick-up unit M that obtains
2Locate current transmission line of electricity current phase value and the said first current phase pick-up unit M
1Locating current transmission line of electricity current phase value compares: if gap is then confirmed the said first current phase pick-up unit M greater than given in advance threshold value between the two
1With the second current phase pick-up unit M
2Between have fault; Otherwise, do not have fault;
The second current phase pick-up unit M
2Said comparative result is passed through the first current phase pick-up unit M
1Pass said base station M back
0And with said phase-detection command signal and the said second current phase pick-up unit M
2Locate current transmission line of electricity current phase value and be sent to the 3rd the most contiguous current phase pick-up unit M
3By that analogy, obtain the current transmission line of electricity current phase value at last current phase pick-up unit place and compare, comparative result is beamed back base station M with the current transmission line of electricity current phase value at previous current phase pick-up unit place until completion
0
Base station M
0According to a plurality of said comparative result that receives, confirm the trouble spot of said overhead transmission line.
2. Fault Locating Method according to claim 1 is characterized in that,
Said base station M
0, said current phase pick-up unit all includes Zigbee CC2530 chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101893034A CN101881803B (en) | 2010-05-24 | 2010-05-24 | Fault localization method of overhead transmission line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101893034A CN101881803B (en) | 2010-05-24 | 2010-05-24 | Fault localization method of overhead transmission line |
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| CN101881803A CN101881803A (en) | 2010-11-10 |
| CN101881803B true CN101881803B (en) | 2012-09-05 |
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| CN2010101893034A Expired - Fee Related CN101881803B (en) | 2010-05-24 | 2010-05-24 | Fault localization method of overhead transmission line |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102087330A (en) * | 2010-11-26 | 2011-06-08 | 上海电力带电作业技术开发有限公司 | Ultrahigh-tension line fault detection and location method and fault detection and location device |
| JP5983755B2 (en) * | 2012-09-28 | 2016-09-06 | 富士通株式会社 | COMMUNICATION DEVICE, COMMUNICATION PROGRAM, COMMUNICATION METHOD, AND COMMUNICATION SYSTEM |
| CN105137290B (en) * | 2015-09-18 | 2018-05-29 | 国网上海市电力公司 | A kind of method at quick definite overhead transmission line earth fault position |
| CN107276043B (en) * | 2016-11-24 | 2019-04-12 | 北京交通大学 | A kind of active distribution network guard method based on electric current positive-sequence component phase change |
| CN106610448A (en) * | 2016-12-15 | 2017-05-03 | 国网江苏省电力公司南京供电公司 | Adaptive overcurrent fault positioning method based on technology of STU recognition network topology |
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|---|---|---|---|---|
| CN101093240A (en) * | 2006-06-23 | 2007-12-26 | 郭玉章 | Method for determining lightning strike point on electric power transmission line |
| CN101216524A (en) * | 2008-01-08 | 2008-07-09 | 国网武汉高压研究院 | 1000KV alternating-current ultrahigh voltage transmission lines earth fault positioning technology and apparatus |
| CN201307148Y (en) * | 2008-10-10 | 2009-09-09 | 孟宪龙 | Power transmission line pole and tower ground fault monitoring and positioning device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06273470A (en) * | 1993-03-19 | 1994-09-30 | Sumitomo Electric Ind Ltd | Accident section plotting device of overhead transmission line |
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2010
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101093240A (en) * | 2006-06-23 | 2007-12-26 | 郭玉章 | Method for determining lightning strike point on electric power transmission line |
| CN101216524A (en) * | 2008-01-08 | 2008-07-09 | 国网武汉高压研究院 | 1000KV alternating-current ultrahigh voltage transmission lines earth fault positioning technology and apparatus |
| CN201307148Y (en) * | 2008-10-10 | 2009-09-09 | 孟宪龙 | Power transmission line pole and tower ground fault monitoring and positioning device |
Non-Patent Citations (1)
| Title |
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| JP特开平6-273470A 1994.09.30 |
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