CN206945889U - A kind of distribution network fault positioning device - Google Patents
A kind of distribution network fault positioning device Download PDFInfo
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- CN206945889U CN206945889U CN201720880841.5U CN201720880841U CN206945889U CN 206945889 U CN206945889 U CN 206945889U CN 201720880841 U CN201720880841 U CN 201720880841U CN 206945889 U CN206945889 U CN 206945889U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
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Abstract
This application discloses a kind of distribution network fault positioning device, it is related to technical field of electric power detection, to solve the problems, such as that the reliability for detecting singlephase earth fault and sensitivity are invented.Main contents include：Fault detector and signal source；Fault detector includes, and test probe is arranged on power distribution network power transmission line；Breakdown judge unit is connected with test probe；First wireless signal Transmit-Receive Unit is connected with breakdown judge unit；The first phase power transmission line, the second phase power transmission line and the third phase power transmission line that signal source includes power distribution network power transmission line are connected with one end of voltage transformer respectively, and the other end of voltage transformer is connected with control unit；Each phase power transmission line of power distribution network power transmission line is connected by one end of high-voltage switch gear and current transformer；The other end of current transformer is connected with control unit；Control unit and the control terminal of high-voltage switch gear connect；Control unit is connected with second wireless singal Transmit-Receive Unit.
Description
Technical field
The application is related to technical field of electric power detection, more particularly to a kind of distribution network fault positioning device.
Background technology
Power distribution network is the end Network of power system, directly contacts user, electric energy and distribution electric energy are supplied to user, it
Reliability level is the concentrated reflection of whole NETWORK STRUCTURE PRESERVING POWER SYSTEM and operation characteristic, directly affects the power supply quality to user.I
The power distribution network of state uses emanant network structure more, more sensitive to failure ratio.According to incompletely statistics, it is main in user's power-off fault
Will be as caused by the failure of distribution system, the influence to customer power supply reliability is very big.Power distribution automation is to improve power supply reliably
Property and power supply quality, the important means that expands power supply capacity, realize the operation of power distribution network high-efficiency and economic, and realize intelligent grid
One of important foundation.The basis of its core content and realization of relying is to carry out monitoring and controlling in real time to power distribution network, in power distribution network
Quick detection and positioning failure when breaking down, diagnosis, is correctly isolated in time, the automatic normal power supply for recovering non-faulting part,
Avoid large area, have a power failure for a long time.
In recent years, single-phase earth fault line selection and location technology continue to develop under the effort of numerous scientific research personnel, are adapted to
Also given birth in all kinds of accident indicators of different occasions with fortune.Accident indicator is applied in power distribution network, can examine in real time
The irregular operating state of electric line, the short circuit of quick detection and positioning line fault or earth fault are measured, helps related personnel fast
Fast isolated fault section, is repaired, and reduces power off time and power failure range.Therefore accident indicator system obtains in China
It is widely applied.
In order to ensure accident indicator in line failure can precision maneuver, before putting into operation, it is necessary to pair therefore
The performance of barrier instruction device is detected.Accident indicator to be checked is installed on the circuit of actual distribution and examined
Survey, it is necessary to the coordination of each power department, time and effort consuming, and safety by power system, economical operation are limited.Therefore, build
Voltage, curent change situation after vertical a set of simulation singlephase earth fault generation, and accident indicator action can be detected
Reliability and the system of sensitivity are that current single-phase earth fault line selection and location technology will continue development and want urgently to be resolved hurrily
Problem.
Utility model content
This application provides a kind of distribution network fault positioning device, to solve the reliability and the spirit that detect singlephase earth fault
The problem of sensitivity.
This application provides a kind of distribution network fault positioning device, the device includes：Fault detector and signal source；
The fault detector includes breakdown judge unit, the first wireless signal Transmit-Receive Unit and test probe, including
One test probe, the second test probe and the 3rd test probe；
The power distribution network power transmission line includes the first phase power transmission line, the second phase power transmission line and third phase power transmission line, and described first
Test probe is arranged on the first phase power transmission line, and second test probe is arranged on the second phase power transmission line, institute
The 3rd test probe is stated to be arranged on the third phase power transmission line；
The breakdown judge unit is connected with the test probe, for judging whether each phase distribution wire of the power distribution network goes out
Existing failure；
The first wireless signal Transmit-Receive Unit is connected with the breakdown judge unit, and the first wireless signal transmitting-receiving is single
Member is used to send and receive wireless signal；
The signal source includes：Voltage transformer, high-voltage switch gear, control unit, current transformer and second wireless singal
Transmit-Receive Unit；
The first phase power transmission line, the second phase power transmission line and the third phase power transmission line of the power distribution network power transmission line respectively with the electricity
One end connection of transformer is pressed, the other end of the voltage transformer is connected with described control unit；
The high-voltage switch gear includes first switch, second switch and the 3rd switch, and the first phase power transmission line passes through described
First switch is connected with the current transformer, and the second phase power transmission line passes through the second switch and the current transformer
Connection, the third phase power transmission line are connected by the described 3rd switch with the current transformer；
The other end of the current transformer is connected with described control unit；
Described control unit is connected with the control terminal of the high-voltage switch gear；
Described control unit is connected with the second wireless singal Transmit-Receive Unit.
Preferably, the first wireless signal Transmit-Receive Unit include wireless network transceiver module WIFI or general packet without
Line service module GPRS.
Preferably, the second wireless singal Transmit-Receive Unit include wireless network transceiver module WIFI or general packet without
Line service module GPRS.
A kind of distribution network fault positioning device that the application provides, can find trouble point in time, and preciousness is provided for maintenance
Time.Possess system phase voltage, residual voltage monitoring function；Possesses earth current monitoring function.It can monitor and be delivered newspaper in active
Alert, fault message and system voltage etc..By finding failure, in time by GSM GPRS or fiber optic communication upload information to master
Stand, be accurately positioned trouble point.Implement simply, cost is low, and reliability is high.
Brief description of the drawings
In order to illustrate more clearly of the technical scheme of the application, letter will be made to the required accompanying drawing used in embodiment below
Singly introduce, it should be apparent that, for those of ordinary skills, without having to pay creative labor,
Other accompanying drawings can also be obtained according to these accompanying drawings.
Fig. 1 is a kind of structural representation for distribution network fault positioning device that the application provides.
Brief description of the drawings：1- power distribution network power transmission lines, 11- the first phase power transmission lines, 12- the second phase power transmission lines, the transmission of electricity of 13- third phases
Line, 2- fault detectors, 21- breakdown judge units, 22- the first wireless signal Transmit-Receive Units, 23- test probes, 231- first
Test probe, the test probes of 232- second, the test probes of 233- the 3rd, 3- signal sources, 31- voltage transformers, 32- height press off
Close, 321- first switches, 322- second switches, 323- the 3rd is switched, 33- control units, 34- current transformers, the nothings of 35- second
Line signal transmitting and receiving unit.
Embodiment
Single-phase earthing is 10kV (35kV) single-phase earthing of small current earthing system, and singlephase earth fault is that distribution system is most normal
The failure seen, mostly occur in moist, rainy weather.Due on screen of trees, distribution line insulator it is single-phase breakdown, single-phase wire break and
Caused by the factors such as toy harm.Single-phase earthing not only have impact on the normal power supply of user, and there may be excessively electric
Pressure, burns out equipment, or even cause phase fault and expand accident.Most of China's 3~63kV power systems use neutral point not
Ground connection or the method for operation through grounding through arc, as small current neutral grounding system.In small current neutral grounding system, single-phase earthing
It is a kind of common provisional failure, mostly occurs in moist, rainy weather.After generation single-phase earthing, failure phase-to-ground voltage drop
It is low, the phase voltage rise of non-faulting two-phase, but line voltage is still symmetrical, thus the continuous power supply to user is not influenceed, system
1~2h can be run, this is also the great advantage of small current neutral grounding system.But power network is transported for a long time when if singlephase earth fault occurs
OK, because two phase-to-ground voltages of non-faulting raise, the weak link of insulation may be caused breakdown, develop into phase fault,
Make fault spread, influence the normal electricity consumption of user.It is also possible to make voltage transformer serious saturation unshakable in one's determination, causes voltage transformer tight
Again overload and burn.Arc grounding can also cause total system overvoltage simultaneously, and then damage equipment, destroy system and transport safely
OK.
When distribution network line breaks down, the often appearance of a trouble point, it can cause and all be broken down on a circuit
Failure, so needing to position specific abort situation, to accelerate the service work of distribution line, reduce power supply user's
Loss.
Referring to Fig. 1, a kind of structural representation of the distribution network fault positioning device provided for the application.As shown in figure 1, should
Device includes：
Fault detector 2 and signal source 3；
The fault detector 2 includes breakdown judge unit 21, the first wireless signal Transmit-Receive Unit 22 and test probe 23,
Including the first test probe 231, the second test probe 232 and the 3rd test probe 233；
The power distribution network power transmission line 1 includes the first phase power transmission line 11, the second phase power transmission line 12 and third phase power transmission line 13, institute
State the first test probe 231 to be arranged on the first phase power transmission line 11, second test probe 232 is arranged on described second
On phase power transmission line 12, the 3rd test probe 233 is arranged on the third phase power transmission line 13；
The breakdown judge unit 21 is connected with the test probe 23, for judging that each phase distribution wire of the power distribution network is
No failure；
The first wireless signal Transmit-Receive Unit 22 is connected with the breakdown judge unit 21, and first wireless signal is received
Bill member 22 is used to send and receive wireless signal；
The signal source 3 includes：Voltage transformer 31, high-voltage switch gear 32, control unit 33, current transformer 34 and second
Wireless signal Transmit-Receive Unit 35；
The first phase power transmission line 11, the second phase power transmission line 12 and the third phase power transmission line 13 of the power distribution network power transmission line 1 are distinguished
It is connected with one end of the voltage transformer 31, the other end of the voltage transformer 31 is connected with described control unit 33；
The high-voltage switch gear 32 includes first switch 321, the switch of second switch 322 and the 3rd 323, the first phase transmission of electricity
Line 11 is connected by the first switch 321 with the current transformer 34, and the second phase power transmission line 12 passes through described second
Switch 322 is connected with the current transformer 34, and the third phase power transmission line 13 passes through the described 3rd switch 323 and the electric current
Transformer 34 connects；
The other end of the current transformer 34 is connected with described control unit 33；
Described control unit 33 is connected with the control terminal of the high-voltage switch gear 32；
Described control unit 33 is connected with the second wireless singal Transmit-Receive Unit 35.
The distribution network fault positioning device that the application provides, again on distribution network line, its installation site can be for installation：It is long
The stage casing of circuit and branch inlet, indicate circuit fault section and fault branch；Substation exit, distinguish it is the outer event in standing or station
Barrier；With distribution transforming high pressure point of incoming cables, distinguish whether failure is caused by user's reason；Cable and overhead line junction, distinguishing failure is
It is no in cut cable.During normal operation, instruction device window is white displays；When breaking down, window board turning is red and flash of light
Display.Distribution network failure instruction device is provided simultaneously with the indicator function of short trouble and singlephase earth fault mostly.In addition,
If desired, accident indicator can also have the simple circuit monitoring running state ability such as load current, conductor temperature.
The distribution network fault positioning device that the application provides, realization pair is coordinated by fault detector 2 and signal source 3 jointly
The positioning of distribution network failure.Fault detector 2 is used to judge that circuit whether there is failure, and signal source 3 is used for according in power distribution network
Each phase current or voltage produce square-wave signal.When the curtage of the distribution network line that is detected in fault detector 2
Whether change matches the particular location for determining distribution network failure with square-wave signal caused by signal source 3.
The test probe 23 of fault detector 2 is arranged on each phase power transmission line of power distribution network power transmission line 1, can test distribution
Curtage on each phase power transmission line of net.The power transmission line of existing power distribution network is generally 3 phases electricity, i.e. power distribution network power transmission line
1 includes the first phase power transmission line 11, the second phase power transmission line 12 and third phase power transmission line 13.In order to test the electric current of each phase power transmission line or
Voltage, test probe 23 is all set on each phase power transmission line.On the first phase power transmission line 11 be provided with the first test probe 231,
The second test probe 232 is provided with the second phase power transmission line 12, the 3rd test probe 233 is provided with the 3rd power transmission line.First
Test probe 231, the second test probe 232 and the 3rd test probe 233 are connected with breakdown judge unit 21 respectively, breakdown judge
The curtage value that unit 21 is tested according to test probe 23 judges whether the curtage on the power transmission line is normal.Failure
Judging unit 21 is connected with the first wireless signal Transmit-Receive Unit 22, and the first wireless signal Transmit-Receive Unit 22 is used to send and receive nothing
The square-wave signal that line signal, i.e. reception signal source 3 are sent, and transmit to breakdown judge unit 21, sentenced by breakdown judge unit 21
Whether the test point of the disconnected fault detector 2 is trouble point, and the judged result of breakdown judge unit 21 is received by the first wireless signal
Send out module to send, send to main station system to realize the positioning to trouble point.
Signal source 3 is used for the characteristic signal for producing positioning failure, including voltage transformer 31, high-voltage switch gear 32, control list
Member 33, current transformer 34 and second wireless singal Transmit-Receive Unit 35.Each phase power transmission line of power distribution network power transmission line 1 respectively with high pressure
One end connection of transformer, the other end of voltage transformer 31 are connected with control unit 33, and power distribution network power transmission line 1 is each mutually to transmit electricity
Line is connected by high-voltage switch gear 32 with one end of current transformer 34, and the other end and the control unit 33 of current transformer 34 connect
Connect, formed from power distribution network power transmission line 1 to current transformer 34 or voltage transformer 31 in the path of controller, realized to distribution
Net the detection of electric current and voltage on each phase power transmission line.Each phase power transmission line of power distribution network power transmission line 1 passes through high-voltage switch gear 32 and electric current
Transformer 34 is connected, and control unit 33 is connected with the control terminal of high-voltage switch gear 32, and control unit 33 starts control signal, control
The switching of high-voltage switch gear 32 processed, to realize the connection opportunity of each phase power transmission line and current transformer 34.Each phase is transmitted electricity in order to realize
The control of line, high-voltage switch gear 32 include first switch 321, the switch of second switch 322 and the 3rd 323.Wherein, the first phase power transmission line
11 are connected by first switch 321 with current transformer 34, the second phase power transmission line 12 by with second switch 322 and Current Mutual Inductance
Device 34 is connected, and third phase power transmission line 13 is connected by the 3rd switch 323 with current transformer 34.Also include second in signal source 3
Wireless signal Transmit-Receive Unit 35, for sending the square-wave signal of the formation of control unit 33.Square-wave signal, by load current, electric current
Signal sequence amplitude, singlephase earth fault delivery time, the start-up study of signal source 3, signal source 3 act after the locking moment, open
Close equipment single closing time, switchgear single switching time, and switchgear and put into last separating brake for the first time
Time collectively forms.
Preferably, the breakdown judge unit 21, is used for：Judge line voltage, the transmission of electricity of the second phase of the first phase power transmission line 11
Whether the line voltage of line 12 and the line voltage of third phase power transmission line 13 change；Judge whether residual voltage is more than preset threshold
Value.
For singlephase earth fault, exemplary includes three kinds of situations.First, it is if a certain phase partial earth, i.e., logical
High resistance or arcing ground are crossed, the voltage of failure phase reduces, and the voltage rise of non-faulting phase, the voltage of non-faulting phase is more than normally
Phase voltage, but do not reach line voltage.Voltage at the open delta of voltage transformer 31 reaches setting valve, and voltage relay moves
Make, send ground signalling.Second, if a certain phase dead ground, the voltage of failure phase drops to zero, the voltage liter of non-faulting phase
Height arrives line voltage.Now occur being three times in original phase voltage, voltage relay action, hair at the open delta of voltage transformer 31
Go out ground signalling.3rd, if there is a certain phase broken string or fuse member fusing, the finger of failure phase in the high-pressure side of voltage transformer 31
Show and be not zero, this is due to that this phase voltage table is connected back in secondary circuit through mutual inductor coil and the formation of other two-phase voltage tables
Road, there is smaller voltage instruction, but be not the phase virtual voltage, non-faulting is still mutually phase voltage.Transformer open delta
35V or so magnitudes of voltage, and starting relay occurs in place, sends ground signalling.
So breakdown judge unit 21 is, it is necessary to detect the line voltage of the first phase power transmission line 11, the line of the second phase power transmission line 12
The line voltage of voltage and third phase power transmission line 13, and judge whether it changes, while also need to whether judge residual voltage
More than preset threshold value.Whether change and whether be more than the judgement of preset threshold value to voltage, can be judged by voltage comparator,
Here the comparative approach that breaches a dyke of voltage comparator is no longer described in detail.
Preferably, the first wireless signal Transmit-Receive Unit 22 includes wireless network transceiver module WIFI or general packet
Wireless Services Module GPRS.
In order to realize the transmission of wireless signal, WIFI module can be used, GPRS module, both uses can also be used
Mode is identical, can be according to setting the geographical environment of fault detector 2, the distance of fault detector 2 and signal source 3 and not
The characteristics of with module, it is determined that the module for being used to realize radio communication that final first wireless transmit/receive units are chosen.
If including GPRS module again in wireless signal Transmit-Receive Unit and including WIFI module certainly, can equally realize
The transmission of wireless signal, but more its of part included for outdoor equipment there is a possibility that failure is also bigger, institute
To be more than advantage the shortcomings that the program, often not as implementation.
Preferably, the second wireless singal Transmit-Receive Unit 35 includes wireless network transceiver module WIFI or general packet
Wireless Services Module GPRS.
Restriction for second wireless singal Transmit-Receive Unit 35 is similar to the restriction of the first signal transmitting and receiving unit, here no longer
Repeat.
Preferably, described control unit 33, it is used for：The on off state of the high-voltage switch gear 32 is controlled, in order to the side of generation
Signal wave current.
A kind of distribution network fault positioning device that the application provides, can find trouble point in time, and preciousness is provided for maintenance
Time.Possess system phase voltage, residual voltage monitoring function；Possesses earth current monitoring function.It can monitor and be delivered newspaper in active
Alert, fault message and system voltage etc..By finding failure, in time by GSM GPRS or fiber optic communication upload information to master
Stand, be accurately positioned trouble point.Implement simply, cost is low, and reliability is high.
In this specification between each embodiment identical similar part mutually referring to.Above-described practicality is new
Type embodiment does not form the restriction to scope of protection of the utility model.
Claims (3)
1. a kind of distribution network fault positioning device, it is characterised in that described device includes：Fault detector (2) and signal source
(3)；
The fault detector (2) includes breakdown judge unit (21), the first wireless signal Transmit-Receive Unit (22) and test probe
, including the first test probe (231), the second test probe (232) and the 3rd test probe (233) (23)；
The power distribution network power transmission line (1) includes the first phase power transmission line (11), the second phase power transmission line (12) and third phase power transmission line
(13), first test probe (231) is arranged on the first phase power transmission line (11), second test probe (232)
It is arranged on the second phase power transmission line (12), the 3rd test probe (233) is arranged on the third phase power transmission line (13)
On；
The breakdown judge unit (21) is connected with the test probe (23), for judging that each phase distribution wire of the power distribution network is
No failure；
The first wireless signal Transmit-Receive Unit (22) is connected with the breakdown judge unit (21), and first wireless signal is received
Bill member (22) is used to send and receive wireless signal；
The signal source (3) includes：Voltage transformer (31), high-voltage switch gear (32), control unit (33), current transformer (34)
With second wireless singal Transmit-Receive Unit (35)；
The first phase power transmission line (11), the second phase power transmission line (12) and the third phase power transmission line (13) of the power distribution network power transmission line (1)
One end with the voltage transformer (31) is connected respectively, the other end and described control unit of the voltage transformer (31)
(33) connect；
The high-voltage switch gear (32) includes first switch (321), second switch (322) and the 3rd switch (323), first phase
Power transmission line (11) is connected by the first switch (321) with the current transformer (34), the second phase power transmission line (12)
It is connected by the second switch (322) with the current transformer (34), the third phase power transmission line (13) passes through described
Three switches (323) are connected with the current transformer (34)；
The other end of the current transformer (34) is connected with described control unit (33)；
Described control unit (33) is connected with the control terminal of the high-voltage switch gear (32)；
Described control unit (33) is connected with the second wireless singal Transmit-Receive Unit (35).
2. device as claimed in claim 1, it is characterised in that the first wireless signal Transmit-Receive Unit (22) includes wireless network
Network transceiver module WIFI or GPRS module GPRS.
3. device as claimed in claim 1, it is characterised in that the second wireless singal Transmit-Receive Unit (35) includes wireless network
Network transceiver module WIFI or GPRS module GPRS.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720880841.5U CN206945889U (en) | 2017-07-19 | 2017-07-19 | A kind of distribution network fault positioning device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720880841.5U CN206945889U (en) | 2017-07-19 | 2017-07-19 | A kind of distribution network fault positioning device |
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| Publication Number | Publication Date |
|---|---|
| CN206945889U true CN206945889U (en) | 2018-01-30 |
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ID=61370852
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107247217A (en) * | 2017-07-19 | 2017-10-13 | 云南电网有限责任公司电力科学研究院 | A kind of distribution network fault positioning device |
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2017
- 2017-07-19 CN CN201720880841.5U patent/CN206945889U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107247217A (en) * | 2017-07-19 | 2017-10-13 | 云南电网有限责任公司电力科学研究院 | A kind of distribution network fault positioning device |
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