CN206274340U - Power cable shelf depreciation both-end positioning characteristic pulse generating means and its system - Google Patents
Power cable shelf depreciation both-end positioning characteristic pulse generating means and its system Download PDFInfo
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- CN206274340U CN206274340U CN201621195802.3U CN201621195802U CN206274340U CN 206274340 U CN206274340 U CN 206274340U CN 201621195802 U CN201621195802 U CN 201621195802U CN 206274340 U CN206274340 U CN 206274340U
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Abstract
The utility model provides power cable shelf depreciation both-end positioning characteristic pulse generating means and its system, and characteristic pulse rising edge, characteristic pulse width and characteristic pulse repetition rate can be changed by the circuit parameter adjusted in characteristic pulse generating unit.When tested cable is more long, measuring unit is placed in the near-end of tested cable, synchronization unit is set in its distal end；Cable proximal measurement unit is by the first High Frequency Current Sensor by Gauss feature pulse by cable transmission to cable distal end, distal end synchronization unit reflects same characteristic features Gaussian pulse by the second High Frequency Current Sensor immediately after detecting Gauss feature pulse, by calculating partial discharge pulse's digital partial discharge source position.The utility model provides brand-new solution for long range power cable shelf depreciation positioning.
Description
【Technical field】
The utility model is related to Electric Power Equipment Insulation detection technique and its application field, more particularly to power cable part
Discharge examination and positioning correlative technology field.
【Background technology】
As China's Development of China's Urbanization is accelerated, the installation of cable and usage amount are increasing in urban power distribution network.It is how true
Protect the safe operation of a large amount of cables, improve outstanding problem of the power network power supply reliability as distribution network operation and management.In recent years
The distribution cable Partial Discharge Detection and location technology for growing up, due to non-intruding, it is lossless, efficient the advantages of obtain people's
Extensive concern.
Patent of invention CN 104655995A disclose a kind of power cable partial discharge source both-end localization method, and measuring unit sets
Put in power cable near-end, triggering reflector element is arranged on power cable distal end, and Partial discharge signal reaches proximal measurement unit, while
Pulse signal is sent into transmitter module to amplify and be sent to cable by another high frequency cable transformer, and is transferred to survey
Amount end positioning partial discharge source.
Knowable to technical characteristic disclosed in above-mentioned patent, its research emphasis essentially consists in both-end positioning general principle and thinks
Road, however, in actual applications, the signal for how differentiating reception is exactly that echo signal is a problem, because in practical application
In, the pulse signal that transmitter module sends can be very weak, and in the case where other interference signals such as noise are very powerful, it is impossible to
Accurately receive echo signal.
In order to solve the above technical problems, it has been proposed that the target impulse signal that will send sends again after amplifying, making powerful
Target impulse signal be easily received, do so can solve certain technical problem to a certain extent.However, ability
Field technique personnel know, the pulse signal or noise signal that either send or other interference signals, and it is with distance
Increase, it shows as sinusoidal decay signal, so, in actual applications, can by interference signal be mistakened as into target pulse letter
Number receive.So, for whole detecting system, its final accuracy rate will have a greatly reduced quality.
In order to solve the above technical problems, real be necessary to provide a kind of technical scheme that can solve above technical problem.
【Utility model content】
The utility model provide power cable shelf depreciation both-end positioning characteristic pulse generating means and its system and
Method, from pulse feature in itself, using synchronous single in the combined type of one with sensing function with impulse ejection
Unit, is conceived to and how to obtain effective characteristic pulse, enhancing scene antijamming capability and be accurately positioned discharge position, is cable
Shelf depreciation positioning provides basis and ensures.
To achieve the above object, the utility model uses following technical scheme：
A kind of power cable shelf depreciation both-end positioning uses characteristic pulse generating means, including characteristic pulse shaping unit
WH, this feature pulse shaping unit WH include input port a and input port b and output port c and output port d, the spy
Levying pulse shaping unit WH includes the first circuit and second circuit that are coupled by electric capacity of voltage regulation C1, wherein, described first
Circuit includes the first diode D1, the second diode D2, the 3rd diode D3 and the 4th diode D4, wherein, it is cascaded
The first diode D1 and the second diode D2 be connected in parallel with the 3rd diode D3 being cascaded and the 4th diode D4,
The input port a is connected to the node between the first diode D1 and the second diode D2, and the input port b is connected to
Node between three diode D3 and the 4th diode D5；The second circuit includes the inductance L1 and the 5th diode of series connection
D5, the 5th diode two ends are parallel with electric capacity C2, are further connected with electric capacity C3 in the output end of second circuit, the electric capacity
C3 is connected in parallel on output port c and output port the d two ends of pulse generating unit.
The output end of the characteristic pulse shaping unit WH is further connected with characteristic pulse generating unit RPG, the spy
Levy impulse generating unit RPG main by the 6th diode D6, the 4th electric capacity C4, pulse transformer T, the 5th electric capacity C5 and the 7th
Diode D7 is constituted；The input port 1 of described characteristic pulse generating unit RPG is connected with the anode of the 6th diode D6, the
The negative electrode of six diode D6 is connected with the 4th electric capacity C4 left ends, and the 4th electric capacity C4 right-hand members are connected for 11 points with pulse transformer T primary sides,
12 points of pulse transformer T primary sides are connected with input port 2；21 points of pulse transformer T secondary is connected with one end of the 5th electric capacity C5,
The other end of the 5th electric capacity C5 is connected with the anode and output interface 3 of the 7th diode D7, the negative electrode of the 7th diode D7 with
22 points of pulse transformer T and output port 4 are connected.
Up to 10MHz, dielectric strength is 20kV to the maximum pulse rate of the pulse transformer T.
Power outlet is connected to the input of the characteristic pulse shaping unit WH by Industrial Frequency Transformer.
The Industrial Frequency Transformer TF uses racetrack core structure, its primary and secondary side electrical isolation.
The primary side of the Industrial Frequency Transformer TF is connected on the zero line and live wire of power outlet, the Industrial Frequency Transformer
The secondary of TF is connected to two inputs of characteristic pulse shaping unit WH.
The class of insulation of the Industrial Frequency Transformer TF is not less than 20kV.
A kind of detecting system of power cable shelf depreciation both-end positioning local discharge signal, including it is socketed in electricity to be measured
First HF current transformer of cable near-end, the output end of first HF current transformer is connected with measuring unit, by surveying
Amount unit sends the Gauss feature pulse that pulse generating unit is produced, and has the second high frequency electric mutual in the distal end clamp of cable under test
Sensor, the input of second HF current transformer is connected with reflector element, is sent from measuring unit for receiving and recognizing
Gauss feature pulse；The input of first HF current transformer and the output end difference of the second HF current transformer
It is connected with power cable shelf depreciation both-end positioning characteristic pulse generating means；The Gauss feature pulse curve and interference source
The sinusoidal decay curve of generation is entirely different.
Compared with prior art, the utility model at least has the advantages that：The utility model characteristic pulse occurs
When device is used for long range power cable Partial Discharge Detection with positioning, possess that feature identification is convenient, pulse amplitude is adjustable, repeat
The features such as frequency-adjustable, improve the synchronous reliability of cable both-end, accuracy and antijamming capability.When tested cable is more long
When, measuring unit is placed in the near-end of tested cable, in its distal end, synchronization unit is set；Cable proximal measurement unit passes through first
By Gauss feature pulse by cable transmission to cable distal end, distal end synchronization unit detects Gauss feature to High Frequency Current Sensor
Same characteristic features Gaussian pulse is reflected by the second High Frequency Current Sensor immediately after pulse, by calculating partial discharge pulse's time
Difference positioning partial discharge source position.The utility model provides brand-new solution for long range power cable shelf depreciation positioning.
【Brief description of the drawings】
The above is only the utility model plan explanation, in order to become apparent from illustrating technological means of the present utility model, with
Lower combination accompanying drawing elaborates with specific embodiment to the utility model.
Fig. 1 is the composition of the utility model power cable shelf depreciation both-end positioning characteristic pulse generating means and system
Schematic diagram.
Fig. 2 is that the utility model power cable shelf depreciation both-end positioning characteristic pulse generating means is whole with system pulses
The composition schematic diagram of shape unit (WH).
Fig. 3 is the utility model power cable shelf depreciation both-end positioning characteristic pulse generating means and system features arteries and veins
Rush the basic composition schematic diagram of generating unit (RPG).
【Specific embodiment】
Refer to shown in Fig. 2, occur with characteristic pulse the utility model discloses power cable shelf depreciation both-end positioning
Device, mainly including power outlet, Industrial Frequency Transformer TF, characteristic pulse shaping unit WH, characteristic pulse generating unit RPG.
The power outlet has three contacts G, N, L, wherein contact G ground connection, contact N (zero line) and Industrial Frequency Transformer TF
The pin of primary side 1 is connected, and contact L (live wire) is connected with the pin of Industrial Frequency Transformer TF primary sides 2.The pin of Industrial Frequency Transformer TF secondary 3 and spy
Levy pulse shaping unit WH inputs a points to be connected, the pin of Industrial Frequency Transformer TF secondary 4 and characteristic pulse shaping unit WH inputs b
Point is connected.The characteristic pulse shaping unit WH output ends c points are connected with characteristic pulse generating unit RPG1 pin, and characteristic pulse is whole
Shape unit WH output ends d points are connected with characteristic pulse generating unit RPG2 pin.Characteristic pulse generating unit RPG3 pin and tested electricity
One end of cable is connected, and 4 pin of characteristic pulse generating unit RPG are connected with the other end of tested cable.
The Industrial Frequency Transformer TF uses racetrack core structure, and primary side input voltage virtual value is 220VAC, and secondary is defeated
Go out voltage effective value for 100VAC, there is tap in the middle of secondary, tap is common ground end.The Industrial Frequency Transformer TF transformers are adopted
With isolation structure, primary and secondary side is electrically isolated completely to.The Industrial Frequency Transformer TF classes of insulation are to be not less than 20kV.
The characteristic pulse shaping unit WH is main by the first diode D1, the second diode D2, the 3rd diode D3, the
Four diode D4, electric capacity of voltage regulation C1, resonant inductance L1, the 5th diode D5, the second electric capacity C2, the 3rd electric capacity C3 are constituted.
The anode and the second diode D2 of the input port a of described characteristic pulse generating means and the first diode D1
Negative electrode connection；Input port b is connected with the anode of the 3rd diode D3 and the negative electrode of the 4th diode D4；First diode
The negative electrode of D1 is connected with the left end of the negative electrode, the upper end of electric capacity of voltage regulation C1 and resonant inductance L1 of the 3rd diode D3；Two or two
The anode of the anode of pole pipe D2 and the 4th diode D4, the lower end of electric capacity of voltage regulation C1, the lower end of the 3rd electric capacity C3 and output end
Mouth d is connected.The right-hand member of resonant inductance L1 is connected with the anode of the 5th diode D5 and the left end of the second electric capacity C2.Five or two pole
The right-hand member of the negative electrode of pipe D5 and the second electric capacity C2, the 3rd electric capacity C3 upper ends and output interface c are connected.
The characteristic pulse generating unit RPG is main by the 6th diode D6, the 4th electric capacity C4, pulse transformer T, the 5th
Electric capacity C5 and the 7th diode D7 is constituted.
Described characteristic pulse generating unit RPG input ports 1 are connected with the anode of the 6th diode D6, the 6th diode
The negative electrode of D6 is connected with the 4th electric capacity C4 left ends, and the 4th electric capacity C4 right-hand members are connected for 11 points with pulse transformer T primary sides, pulse transforming
12 points of device T primary sides are connected with input port 2；21 points of pulse transformer T secondary is connected with one end of the 5th electric capacity C5, the 5th electric capacity
The other end of C5 is connected with the anode and output interface 3 of the 7th diode D7, the negative electrode and pulse transforming of the 7th diode D7
22 points of device T and output port 4 are connected.
Up to 10MHz, dielectric strength is 20kV to the maximum pulse rate of the pulse transformer T.
A kind of also disclosed the positioning based on power cable shelf depreciation both-end of the utility model uses characteristic pulse generating means
Local discharge signal detecting system, including be socketed in the first HF current transformer of cable under test near-end, first high frequency
The output end of current transformer is connected with measuring unit, and the Gauss feature arteries and veins that pulse generating unit is produced is sent by measuring unit
Punching, has the second HF current transformer in the distal end clamp of cable under test, the input connection of second HF current transformer
There is reflector element, for receiving and recognizing the Gauss feature pulse sent from measuring unit.
, it is necessary to two characteristic pulses of the present utility model are filled in the utility model local discharge signal detecting system
Put, one of them is connected to the input of the first HF current transformer, for producing Gauss feature pulse, another connection
In the output end of the second HF current transformer, after the second HF current transformer receives Gauss feature pulse, it sends
Instruction, makes the characteristic pulse generating means for being connected to its output end produce the pulse of identical Gauss feature and is reflected back electricity to be measured
The near-end of cable, after cable under test receives the Gauss feature pulse of reflection proximally by the first HF current transformer, you can
Position partial discharge source and obtain position by calculating partial discharge pulse's time difference.
Specifically include following steps：
The first HF current transformer is socketed in power cable near-end first, its signal output part is connected with measuring unit
Connect；Then the second HF current transformer is covered into clamp in the distal end of power cable, its interface end is connected with distal end reflector element
Connect；Driving pulse is sent by measuring unit, is propagated to the distal end of power cable, distal end reflector element is in the distal end of power cable
After receiving synchronous characteristic pulse and identification, the pulse for sending same feature immediately by the second HF current transformer is surveyed to near-end
Amount unit, proximal measurement unit receives reflectance signature pulse by the first HF current transformer, measures total time for T, so
Characteristic pulse understands to be T/2 between the unidirectional sowing time along whole cable, and spread speed v=2L/T, L are total cable length；Part is put
Electricity occurs at certain moment, and pulse is propagated to cable two ends, and according to cable near-end wave recording, the first current sensor is in time t1
Receive first pulse, second pulse that the other end is reflected is received in time t2, then the position that shelf depreciation occurs
Putting x can be by formula：X=(T+t1-t2) v/2 is calculated.
Gauss feature pulse curve described in the utility model is entirely different with sinusoidal decay curve, by contrast, can be with
The pulsion phase that easily other interference sources such as the pulse and noise are produced is distinguished.
Repeated characteristic pulse generating unit disclosed in the utility model produces nanosecond steep-front Gauss feature pulse, passes through
Circuit parameter in regulation characteristic pulse generating unit (RPG) can change characteristic pulse rising edge, characteristic pulse width and spy
Levy pulse recurrence frequency.When this feature pulse generating unit is used for long range power cable Partial Discharge Detection with positioning, possess
The features such as feature identification is convenient, pulse amplitude is adjustable, repetition rate is adjustable, improves the synchronous reliability of cable both-end, accurate
Property and antijamming capability.When tested cable is more long, measuring unit is placed in the near-end of tested cable, set synchronous in its distal end
Unit；Cable proximal measurement unit is remote to cable by cable transmission by Gauss feature pulse by the first High Frequency Current Sensor
End, distal end synchronization unit reflects same characteristic features Gauss by the second High Frequency Current Sensor immediately after detecting Gauss feature pulse
Pulse, by calculating partial discharge pulse's digital partial discharge source position.The utility model is long range power cable part
Breakdown location provides brand-new solution.
The utility model provides power cable shelf depreciation both-end positioning and uses characteristic pulse generating means, with safety, just
Take, it is accurate the features such as, solve the rising edge steepness of current long-distance cable shelf depreciation positioning synchronous pulse, pulse width,
The problems such as repetition rate can not adjust and cause shelf depreciation location misalignment, led to not positioning by scene interference, compensate for working as
Preceding power cable Partial Discharge Detection and location technology deficiency in actual applications.
After using the design, the utility model at least has the following advantages that：
1st, the utility model uses isolated architecture design, and Industrial Frequency Transformer is respectively provided with insulation water enough with pulse transformer
It is flat, it is ensured that security during human users' instrument；
When the 2nd, carrying out Site Detection using the utility model patent, operating personnel are by adjusting characteristic pulse generating unit
(RPG) pulse front edge regulation electric capacity C4 and pulse back edge regulation electric capacity C5, it is convenient to adjust the finger of high-frequency characteristic pulse
Number rising edge, trailing edge, pulse width and repetition rate.The efficiency of staff's detection is improve, before adjusting pulse
The judgement order of accuarcy of initial time can be improved along steepness, so as to improve positioning precision and strengthen live antijamming capability.
3rd, during on-the-spot test, device described in the utility model both can with cable wave of oscillation test system support the use so as to
The shelf depreciation positioning of cable long is realized, can be separately provided again as electrification detection system realizes the powered positioning partial discharge of shelf depreciation
Source, the characteristics of with one-machine-multi-function.
It can be seen that, the utility model is creatively solved at long range power cable Partial Discharge Detection scene, can be conveniently
The circuit parameter of ground regulation characteristic pulse generating unit, realizes rising edge, pulse width and the repetition of high-frequency characteristic Gaussian pulse
Frequency is adjusted, and improves Site Detection effect, positioning precision and antijamming capability.
The above, is only preferred embodiment of the present utility model, and any form is not made to the utility model
On limitation, those skilled in the art make a little simple modification, equivalent variations or modification using the technology contents of the disclosure above,
All fall within protection domain of the present utility model.
Claims (8)
1. a kind of power cable shelf depreciation both-end positioning uses characteristic pulse generating means, it is characterised in that：Including characteristic pulse
Shaping unit (WH), this feature pulse shaping unit (WH) includes input port a and input port b and output port c and defeated
Exit port d, this feature pulse shaping unit (WH) includes the first circuit and second circuit that are coupled by electric capacity of voltage regulation C1,
Wherein, first circuit includes the first diode D1, the second diode D2, the 3rd diode D3 and the 4th diode D4, its
In, the first diode D1 being cascaded and the second diode D2 and the 3rd diode D3 being cascaded and the four or two pole
Pipe D4 is connected in parallel, and the input port a is connected to the node between the first diode D1 and the second diode D2, the input
Port b is connected to the node between the 3rd diode D3 and the 4th diode D5；The second circuit includes the inductance L1 of series connection
With the 5th diode D5, the 5th diode two ends are parallel with electric capacity C2, are further connected with the output end of second circuit
Electric capacity C3, electric capacity C3 are connected in parallel on output port c and output port the d two ends of pulse generating unit.
2. a kind of power cable shelf depreciation both-end positioning according to claim 1 uses characteristic pulse generating means, and it is special
Levy and be：The output end of the characteristic pulse shaping unit (WH) is further connected with characteristic pulse generating unit (RPG), described
Characteristic pulse generating unit (RPG) it is main by the 6th diode D6, the 4th electric capacity C4, pulse transformer T, the 5th electric capacity C5 and
7th diode D7 is constituted；The input port 1 of described characteristic pulse generating unit (RPG) and the anode phase of the 6th diode D6
Even, the negative electrode of the 6th diode D6 is connected with the 4th electric capacity C4 left ends, 11 points of the 4th electric capacity C4 right-hand members and pulse transformer T primary sides
Connection, 12 points of pulse transformer T primary sides are connected with input port 2；One end of 21 points of pulse transformer T secondary and the 5th electric capacity C5
Connection, the other end of the 5th electric capacity C5 is connected with the anode and output interface 3 of the 7th diode D7, the moon of the 7th diode D7
Pole is connected with 22 points of pulse transformer T and output port 4.
3. a kind of power cable shelf depreciation both-end positioning according to claim 2 uses characteristic pulse generating means, and it is special
Levy and be：Up to 10MHz, dielectric strength is 20kV to the maximum pulse rate of the pulse transformer T.
4. a kind of power cable shelf depreciation both-end positioning according to claim 1 uses characteristic pulse generating means, and it is special
Levy and be：Power outlet is connected to the input of the characteristic pulse shaping unit (WH) by Industrial Frequency Transformer.
5. a kind of power cable shelf depreciation both-end positioning according to claim 4 uses characteristic pulse generating means, and it is special
Levy and be：The Industrial Frequency Transformer (TF) uses racetrack core structure, its primary and secondary side electrical isolation.
6. a kind of power cable shelf depreciation both-end positioning according to claim 4 uses characteristic pulse generating means, and it is special
Levy and be：The primary side of the Industrial Frequency Transformer (TF) is connected on the zero line and live wire of power outlet, the power frequency transformation
The secondary of device (TF) is connected to two inputs of characteristic pulse shaping unit (WH).
7. a kind of power cable shelf depreciation both-end positioning according to claim 4 uses characteristic pulse generating means, and it is special
Levy and be：The class of insulation of the Industrial Frequency Transformer (TF) is not less than 20kV.
8. a kind of power cable shelf depreciation both-end positioning based on any one of claim 1-7 occurs with characteristic pulse
The detecting system of the local discharge signal of device, it is characterised in that：The first high frequency electric including being socketed in cable under test near-end
Transformer, the output end of first HF current transformer is connected with measuring unit, and sending pulse generation by measuring unit fills
The Gauss feature pulse of generation is put, has the second HF current transformer in the distal end clamp of cable under test, second high frequency electric
The input of transformer is connected with reflector element, for receiving and recognizing the Gauss feature pulse sent from measuring unit；It is described
The output end of the input of the first HF current transformer and the second HF current transformer is connected to power cable part
Electric discharge both-end positioning uses characteristic pulse generating means；The sinusoidal decay curve that the Gauss feature pulse curve is produced with interference source
It is entirely different.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621195802.3U CN206274340U (en) | 2016-10-28 | 2016-10-28 | Power cable shelf depreciation both-end positioning characteristic pulse generating means and its system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621195802.3U CN206274340U (en) | 2016-10-28 | 2016-10-28 | Power cable shelf depreciation both-end positioning characteristic pulse generating means and its system |
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| Publication Number | Publication Date |
|---|---|
| CN206274340U true CN206274340U (en) | 2017-06-23 |
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ID=59062128
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621195802.3U Expired - Fee Related CN206274340U (en) | 2016-10-28 | 2016-10-28 | Power cable shelf depreciation both-end positioning characteristic pulse generating means and its system |
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| Country | Link |
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| CN (1) | CN206274340U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106353655A (en) * | 2016-10-28 | 2017-01-25 | 西安浩能电气科技有限公司 | Characteristic pulse generating device for power cable partial discharge double-ended location as well as system and method thereof |
-
2016
- 2016-10-28 CN CN201621195802.3U patent/CN206274340U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106353655A (en) * | 2016-10-28 | 2017-01-25 | 西安浩能电气科技有限公司 | Characteristic pulse generating device for power cable partial discharge double-ended location as well as system and method thereof |
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| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20170623 Termination date: 20171028 |