CN106771639B - High pressure pole tower ground resistance on-line monitoring system - Google Patents
High pressure pole tower ground resistance on-line monitoring system Download PDFInfo
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- CN106771639B CN106771639B CN201611153763.5A CN201611153763A CN106771639B CN 106771639 B CN106771639 B CN 106771639B CN 201611153763 A CN201611153763 A CN 201611153763A CN 106771639 B CN106771639 B CN 106771639B
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- 230000001808 coupling Effects 0.000 claims abstract description 16
- 238000010168 coupling process Methods 0.000 claims abstract description 16
- 238000005859 coupling reaction Methods 0.000 claims abstract description 16
- 230000003321 amplification Effects 0.000 claims abstract description 12
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 12
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 14
- 229910052710 silicon Inorganic materials 0.000 claims description 14
- 239000010703 silicon Substances 0.000 claims description 14
- 230000005611 electricity Effects 0.000 claims description 10
- 125000004122 cyclic group Chemical group 0.000 claims description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 9
- 239000003990 capacitor Substances 0.000 claims description 6
- 230000005540 biological transmission Effects 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 4
- 238000007689 inspection Methods 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 230000000875 corresponding Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 101710040088 NTG1 Proteins 0.000 description 1
- 101700070279 SCRA Proteins 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 101700011890 scr1 Proteins 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/20—Measuring earth resistance; Measuring contact resistance, e.g. of earth connections, e.g. plates
- G01R27/205—Measuring contact resistance of connections, e.g. of earth connections
Abstract
A kind of high pressure pole tower ground resistance on-line monitoring system provided by the invention, including constant-current supply, voltage processing circuitry, inverter circuit, power amplification circuit, trap circuit, coupling loader, voltage sensor PT, current sensor CT, control circuit and remote controllers；The output end of the constant-current supply and the input terminal of voltage processing circuitry connect, the output end of voltage processing circuitry and the input terminal of inverter circuit connect, the output end of the inverter circuit and the input terminal of power amplification circuit connect, the output end of power amplification circuit and the input terminal of trap circuit connect, the output end of trap circuit is connect with coupling loader, alternating current is loaded on the anode of the earthing or grounding means of high pressure shaft tower by the coupling loader, the voltage sensor PT is set to the anode of earthing or grounding means, current sensor CT is set to the negative terminal of earthing or grounding means, the output end of voltage sensor PT and current sensor CT connect to the control circuit, control circuit and remote controllers communicate to connect, the constant-current supply is controllable constant-current power supply, the control terminal of the constant-current supply and the order output terminal of control circuit connect.
Description
Technical field
The present invention relates to a kind of electric detection system more particularly to a kind of high pressure pole tower ground resistance on-line monitoring systems.
Background technique
High pressure shaft tower is the important equipment of transmission line of electricity, for being supported to overhead transmission line, is thrown in high pressure shaft tower
Enter in use, needing to be grounded high pressure shaft tower by grounding apparatus；However as the use of grounding apparatus, ground connection can go out
Existing undesirable condition, whether high pressure tower grounding is well generally detected by ground resistance, when ground resistance is less than 10 ohm,
Then show that ground connection is good, otherwise imperfect earth, once there is imperfect earth in high pressure shaft tower, it will cause power supply unit to miss
It is dynamic, cause accident of power supply；There are no the means that the ground resistance to transmission line of electricity is effectively detected in the prior art.
It is, therefore, desirable to provide a kind of high pressure pole tower ground resistance monitors system, can ground resistance to high pressure shaft tower into
Row accurate measurements simultaneously can obtain monitoring data in real time, can effectively avoid manpower, object caused by manual inspection in traditional technology
The waste of power resource effectively ensures that power transmission network continues safe and stable operation.
Summary of the invention
In view of this, the object of the present invention is to provide a kind of high pressure pole tower ground resistance on-line monitoring system, it can be to height
The ground resistance of compression bar tower carries out accurate measurements and can obtain monitoring data in real time, can effectively avoid artificial in traditional technology
The waste of human and material resources resource caused by inspection effectively ensures that power transmission network continues safe and stable operation.
A kind of high pressure pole tower ground resistance on-line monitoring system provided by the invention, including constant-current supply, voltage processing electricity
Road, inverter circuit, power amplification circuit, trap circuit, coupling loader, voltage sensor PT, current sensor CT, control electricity
Road and remote controllers；
The input terminal of the output end of the constant-current supply and voltage processing circuitry connects, the output end of voltage processing circuitry with
The input terminal of inverter circuit connects, and the output end of the inverter circuit and the input terminal of power amplification circuit connect, power amplification
The output end of circuit and the input terminal of trap circuit connect, and the output end of trap circuit is connect with coupling loader, the coupling
Alternating current is loaded on the anode of the earthing or grounding means of high pressure shaft tower by loader, and the voltage sensor PT is set to earthing or grounding means
Anode, current sensor CT are set to the negative terminal of earthing or grounding means, the output end and control of voltage sensor PT and current sensor CT
Circuit connection processed, control circuit and remote controllers communicate to connect, and the constant-current supply is controllable constant-current power supply, the Constant Electric Current
The control terminal in source and the order output terminal of control circuit connect.
It further, further include power circuit, the power circuit is with 5V voltage and the DC/DC of 12V voltage output electricity
Road, the 5V voltage output end of the power circuit and the power end of control circuit connect, at the input terminal and voltage of power circuit
Manage the output end connection of circuit.
Further, the voltage processing circuitry includes resistance R1, resistance R2, capacitor C1 and diode D1；
The output end of the constant-current supply is connect with one end of resistance R2, the other end of resistance R2 and the anode of diode D1
The cathode of connection, diode D1 is connected as the first output end of voltage processing circuitry and the input terminal of inverter circuit, the perseverance
Galvanic electricity source and the points of common connection of resistance R2 are grounded by resistance R1, and the points of common connection of resistance R2 and diode D1 pass through capacitor
C1 ground connection, the points of common connection of resistance R2 and diode D1 as voltage processing circuitry second output terminal and power circuit it is defeated
Enter end connection.
Further, the coupling loader includes cyclic annular iron core and the coil for being wound on cyclic annular iron core, cyclic annular iron core housing
In in the anode connecting wire of earthing or grounding means, the both ends of coil and the positive output end of trap circuit and negative output terminal are connected.
It further, further include protection location, the protection location includes contactor J1 and controllable silicon SCR 1, contactor J1's
One end of coil is connect with the cathode of controllable silicon SCR 1, the coil other end ground connection of contactor J1, the normally closed switch of contactor J1
K1 be set to trap circuit with couple between loader, the anode of controllable silicon SCR 1 is connected to the 12V output end of power circuit, can
The control electrode of control silicon SCR1 connects to the control circuit.
Further, the trap circuit filters out the voltage signal of 50Hz and 50Hz integral multiple.
Beneficial effects of the present invention: high pressure pole tower ground resistance on-line monitoring system of the invention, it can be to high pressure shaft tower
Ground resistance carry out accurate measurements and monitoring data capable of being obtained in real time, can effectively avoid manual inspection in traditional technology from making
At human and material resources resource waste, effectively ensure that power transmission network continues safe and stable operation.
Detailed description of the invention
The invention will be further described with reference to the accompanying drawings and examples:
Fig. 1 is the principle of the present invention figure.
Fig. 2 is the structure chart of coupling loader of the invention.
Specific embodiment
Fig. 1 be the principle of the present invention figure, a kind of high pressure pole tower ground resistance on-line monitoring system provided by the invention, including
Constant-current supply, voltage processing circuitry, inverter circuit, power amplification circuit, trap circuit, coupling loader, voltage sensor PT,
Current sensor CT, control circuit and remote controllers；
The input terminal of the output end of the constant-current supply and voltage processing circuitry connects, the output end of voltage processing circuitry with
The input terminal of inverter circuit connects, and the output end of the inverter circuit and the input terminal of power amplification circuit connect, power amplification
The output end of circuit and the input terminal of trap circuit connect, and the output end of trap circuit is connect with coupling loader, the coupling
Alternating current is loaded on the anode of the earthing or grounding means of high pressure shaft tower by loader, and the voltage sensor PT is set to earthing or grounding means
Anode, current sensor CT are set to the negative terminal of earthing or grounding means, the output end and control of voltage sensor PT and current sensor CT
Circuit connection processed, control circuit and remote controllers communicate to connect, and the constant-current supply is controllable constant-current power supply, the Constant Electric Current
The order output terminal of the control terminal in source and control circuit connects, by above structure, can ground resistance to high pressure shaft tower into
Row accurate measurements simultaneously can obtain monitoring data in real time, can effectively avoid manpower, object caused by manual inspection in traditional technology
The waste of power resource effectively ensures that power transmission network continues safe and stable operation.
Wherein, voltage sensor PT and current sensor are respectively used to the voltage and current signals of detection earthing or grounding means, and
It is input in control circuit, control circuit analyzes the frequency of voltage signal and current signal, excludes power frequency component and integral multiple
In the voltage signal and current signal of power frequency component, ground resistance is then calculated according to voltage signal and current signal, works as ground connection
Resistance is greater than 10 ohm, generates alarm signal if it is less than 10 ohm and then exports corresponding monitoring data to remote controllers；
The trap circuit filters out the voltage signal of 50Hz and 50Hz integral multiple, and trap circuit uses existing circuit, inverter circuit
The voltage signal frequency of output is controlled by control circuit, and control circuit uses existing single-chip microcontroller, and remote controllers use industry control
Host is furnished with corresponding display and order keyboard certainly, belongs to the prior art, and remote controllers and control circuit pass through shifting
Dynamic communication module connection, such as 3G module, 4G module etc.
It further include power circuit in the present embodiment, the power circuit is the DC/ with 5V voltage and 12V voltage output
DC circuit, the 5V voltage output end of the power circuit and the power end of control circuit connect, the input terminal and electricity of power circuit
The output end connection for pressing processing circuit, by this structure, can export stable work electricity consumption to control circuit and protection
Unit.
In the present embodiment, the voltage processing circuitry includes resistance R1, resistance R2, capacitor C1 and diode D1；
The output end of the constant-current supply is connect with one end of resistance R2, the other end of resistance R2 and the anode of diode D1
The cathode of connection, diode D1 is connected as the first output end of voltage processing circuitry and the input terminal of inverter circuit, the perseverance
Galvanic electricity source and the points of common connection of resistance R2 are grounded by resistance R1, and the points of common connection of resistance R2 and diode D1 pass through capacitor
C1 ground connection, the points of common connection of resistance R2 and diode D1 as voltage processing circuitry second output terminal and power circuit it is defeated
Enter end connection, by above structure, on the one hand for the electric current that constant-current supply exports to be converted to voltage, on the other hand can filter
Interference signal out, and diode D1 can play the role of good protection to constant-current supply.
In the present embodiment, the coupling loader includes cyclic annular iron core 1 and the coil 2 for being wound on cyclic annular iron core, cyclic annular iron
Core 1 is coated in the anode connecting wire 3 of earthing or grounding means, the both ends of coil 2 and the positive output end of trap circuit and negative output terminal
Connection, as shown in Fig. 2, being conducive to signal loading facilitating test, wherein attached in Fig. 2 in earthing or grounding means by this structure
Icon note 3 is between earthing or grounding means and shaft tower.
It further include protection location in the present embodiment, the protection location includes contactor J1 and controllable silicon SCR 1, contactor
One end of the coil of J1 is connect with the cathode of controllable silicon SCR 1, and the coil other end ground connection of contactor J1, contactor J1's is normally closed
Switch K1 be set to trap circuit with couple between loader, the anode of controllable silicon SCR 1 be connected to power circuit 12V output
End, the control electrode of controllable silicon SCR 1 connects to the control circuit, and when there is thunder-strike current, voltage sensor and current sensor are defeated
It is much larger than the signal of secure threshold out, control circuit controls controllable silicon SCR 1 and is connected, contactor work, the switch K1 of contactor J1
It disconnects, to prevent lightning current from flowing backwards, after lightning current releases, control circuit control constant-current supply is in temporary dormant state,
The switch K1 of 1 alternating current of controllable silicon SCR at this time, contactor J1 is re-closed, and by above structure, is capable of forming good protection
Effect.
Finally, it is stated that the above examples are only used to illustrate the technical scheme of the present invention and are not limiting, although referring to compared with
Good embodiment describes the invention in detail, those skilled in the art should understand that, it can be to skill of the invention
Art scheme is modified or replaced equivalently, and without departing from the objective and range of technical solution of the present invention, should all be covered at this
In the scope of the claims of invention.
Claims (4)
1. a kind of high pressure pole tower ground resistance on-line monitoring system, it is characterised in that: including constant-current supply, voltage processing circuitry,
Inverter circuit, power amplification circuit, trap circuit, coupling loader, voltage sensor PT, current sensor CT, control circuit
And remote controllers；
The output end of the constant-current supply and the input terminal of voltage processing circuitry connect, the output end of voltage processing circuitry and inversion
The input terminal of circuit connects, and the output end of the inverter circuit and the input terminal of power amplification circuit connect, power amplification circuit
Output end and the input terminal of trap circuit connect, the output end of trap circuit is connect with coupling loader, and the coupling loads
Alternating current is loaded on the anode of the earthing or grounding means of high pressure shaft tower by device, and the voltage sensor PT is being set to earthing or grounding means just
End, current sensor CT are set to the negative terminal of earthing or grounding means, the output end and control of voltage sensor PT and current sensor CT
Circuit connection, control circuit and remote controllers communicate to connect, and the constant-current supply is controllable constant-current power supply, the constant-current supply
Control terminal and control circuit order output terminal connect；
It further include power circuit, the power circuit is the DC/DC circuit with 5V voltage and 12V voltage output, the power supply
The 5V voltage output end of circuit and the power end of control circuit connect, the output of the input terminal and voltage processing circuitry of power circuit
End connection；
It further include protection location, the protection location includes contactor J1 and controllable silicon SCR 1, one end of the coil of contactor J1
It is connect with the cathode of controllable silicon SCR 1, the coil other end ground connection of contactor J1, the normally closed switch K1 of contactor J1 is set to sunken
Wave circuit with couple between loader, the anode of controllable silicon SCR 1 is connected to the 12V output end of power circuit, controllable silicon SCR 1
Control electrode connects to the control circuit.
2. high pressure pole tower ground resistance on-line monitoring system according to claim 1, it is characterised in that: the voltage processing electricity
Road includes resistance R1, resistance R2, capacitor C1 and diode D1；
The output end of the constant-current supply is connect with one end of resistance R2, and the other end of resistance R2 and the anode of diode D1 connect
It connects, the cathode of diode D1 is connected as the first output end of voltage processing circuitry and the input terminal of inverter circuit, the constant current
The points of common connection of power supply and resistance R2 is grounded by resistance R1, and the points of common connection of resistance R2 and diode D1 pass through capacitor C1
The points of common connection of ground connection, resistance R2 and diode D1 are as the second output terminal of voltage processing circuitry and the input of power circuit
End connection.
3. high pressure pole tower ground resistance on-line monitoring system according to claim 1, it is characterised in that: the coupling loader
Including cyclic annular iron core and the coil for being wound on cyclic annular iron core, cyclic annular iron core is coated in the anode connecting wire of earthing or grounding means, line
The both ends of circle and the positive output end of trap circuit and negative output terminal connect.
4. high pressure pole tower ground resistance on-line monitoring system according to claim 1, it is characterised in that: the trap circuit filter
The voltage signal of 50Hz and 50Hz integral multiple out.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611153763.5A CN106771639B (en) | 2016-12-14 | 2016-12-14 | High pressure pole tower ground resistance on-line monitoring system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611153763.5A CN106771639B (en) | 2016-12-14 | 2016-12-14 | High pressure pole tower ground resistance on-line monitoring system |
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| Publication Number | Publication Date |
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| CN106771639A CN106771639A (en) | 2017-05-31 |
| CN106771639B true CN106771639B (en) | 2019-11-15 |
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| Application Number | Title | Priority Date | Filing Date |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109030951A (en) * | 2018-08-27 | 2018-12-18 | 云南电网有限责任公司电力科学研究院 | A kind of on-line measurement system and method for shared electric power tower ground resistance |
| CN109490635B (en) * | 2018-12-25 | 2021-11-26 | 国网江苏省电力有限公司南京供电分公司 | Online monitoring system and online monitoring method for tower grounding resistance |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200953038Y (en) * | 2006-05-15 | 2007-09-26 | 西安四方机电有限责任公司 | Counterpoise comprehensive parameter testing device |
| CN103269056A (en) * | 2013-06-08 | 2013-08-28 | 临沂市拓普网络股份有限公司 | Current detection protection device and method |
| CN204228827U (en) * | 2014-09-04 | 2015-03-25 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | A kind of Tower Impulse Grounding Resistance site survey systems |
| CN104569609A (en) * | 2015-01-04 | 2015-04-29 | 云南电网有限责任公司电力科学研究院 | Tower grounding impedance testing method for measuring abnormal frequency current of down leads |
| CN104678182A (en) * | 2015-01-30 | 2015-06-03 | 河海大学 | Method for measuring tower grounding resistance without disassembling grounding wire |
| CN105021897A (en) * | 2015-08-17 | 2015-11-04 | 国网辽宁省电力有限公司抚顺供电公司 | Tower grounding resistance measurement apparatus without dismounting of grounding down lead, and measurement method thereof |
| CN205120881U (en) * | 2015-08-20 | 2016-03-30 | 浙江凯发电气股份有限公司 | From compound earth -leakage protector leakage detection circuit |
-
2016
- 2016-12-14 CN CN201611153763.5A patent/CN106771639B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN200953038Y (en) * | 2006-05-15 | 2007-09-26 | 西安四方机电有限责任公司 | Counterpoise comprehensive parameter testing device |
| CN103269056A (en) * | 2013-06-08 | 2013-08-28 | 临沂市拓普网络股份有限公司 | Current detection protection device and method |
| CN204228827U (en) * | 2014-09-04 | 2015-03-25 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | A kind of Tower Impulse Grounding Resistance site survey systems |
| CN104569609A (en) * | 2015-01-04 | 2015-04-29 | 云南电网有限责任公司电力科学研究院 | Tower grounding impedance testing method for measuring abnormal frequency current of down leads |
| CN104678182A (en) * | 2015-01-30 | 2015-06-03 | 河海大学 | Method for measuring tower grounding resistance without disassembling grounding wire |
| CN105021897A (en) * | 2015-08-17 | 2015-11-04 | 国网辽宁省电力有限公司抚顺供电公司 | Tower grounding resistance measurement apparatus without dismounting of grounding down lead, and measurement method thereof |
| CN205120881U (en) * | 2015-08-20 | 2016-03-30 | 浙江凯发电气股份有限公司 | From compound earth -leakage protector leakage detection circuit |
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Address after: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant after: State Grid Corporation of China Applicant after: Maintenance Branch of State Grid Chongqing Electric Power Company Address before: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant before: State Grid Corporation of China Applicant before: Maintenance Branch of State Grid Chongqing Electric Power Company |
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Effective date of registration: 20190917 Address after: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant after: State Grid Corporation of China Applicant after: Maintenance Branch of State Grid Chongqing Electric Power Company Applicant after: The Bei Bei of Guo Wang Chongqing City Electrical Power Co. power supply branch Address before: 100031 Xicheng District West Chang'an Avenue, No. 86, Beijing Applicant before: State Grid Corporation of China Applicant before: Maintenance Branch of State Grid Chongqing Electric Power Company |
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