CN105021897A - Tower grounding resistance measurement apparatus without dismounting of grounding down lead, and measurement method thereof - Google Patents

Tower grounding resistance measurement apparatus without dismounting of grounding down lead, and measurement method thereof Download PDF

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Publication number
CN105021897A
CN105021897A CN201510503724.2A CN201510503724A CN105021897A CN 105021897 A CN105021897 A CN 105021897A CN 201510503724 A CN201510503724 A CN 201510503724A CN 105021897 A CN105021897 A CN 105021897A
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CN
China
Prior art keywords
current
tower
module
measurement
pole
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CN201510503724.2A
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Chinese (zh)
Inventor
李春和
葛维春
张宏宇
王飞
陈刚
张运山
胡亚青
刘洪胜
葛长鑫
裴玉杰
史冬鹏
刘强
罗钧
李继东
陈德刚
肖天然
Original Assignee
国网辽宁省电力有限公司抚顺供电公司
国家电网公司
山东达顺电子科技有限公司
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Application filed by 国网辽宁省电力有限公司抚顺供电公司, 国家电网公司, 山东达顺电子科技有限公司 filed Critical 国网辽宁省电力有限公司抚顺供电公司
Priority to CN201510503724.2A priority Critical patent/CN105021897A/en
Publication of CN105021897A publication Critical patent/CN105021897A/en

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Abstract

The invention relates to a tower grounding resistance measurement apparatus without dismounting of a grounding down lead, and a measurement method thereof. The structure of the apparatus is characterized in that a control unit is connected with a power supply module and a measurement protection circuit; the power supply module is connected with an inverted variable-frequency power supply and a current injection point; and he current injection point is connected with a current measurement circuit and a tower foot. The measurement protection circuit is connected with a voltage measurement circuit and a current measurement circuit; the current measurement circuit is connected with a host sending module and a host receiving module; the host sending module and the host receiving module are connected with a current sensor; and the current sensor is connected with tower feet. With the apparatus and method, the wiring difficulty of the test field can be reduced; the work efficiency can be improved; an advanced test means can be provided for the tower grounding resistance test work; and the heavy work of grounding down lead dismounting and cable arrangement work during the previous field testing can be substantially simplified.

Description

A kind ofly exempt from pole tower ground resistance measurement mechanism and the measuring method of tearing down conductor open

Technical field

The present invention relates to a kind of pole tower ground resistance measurement mechanism, particularly relate to one and do not remove tower grounding downlead, and reduce a kind of pole tower ground resistance measurement mechanism and the measuring method of each tower corner connection earth polar line, obtain by short distance microwave wireless transmission technology the device that real-time testing current signal tests pole tower ground resistance, belong to electric power application.

Background technology

The stake resistance of power transmission sequence shaft tower weighs the whether good standard of tower grounding, and grounding resistance is little can reduce counterattack trip-out rate, improves the anti-thunder level of shaft tower, has Great significance to line thunder protection.

Shaft tower generally has 4 pin, for ensureing that the stake resistance of shaft tower meets the limit value of transmission line of electricity operating standard requirement, has the grounded screen that radioactivity earthing pole is formed or the grounded screen be made up of annular earthing pole at each pin of column foot.In recent years when periodicity measurement circuit pole tower ground resistance, due to pole and tower foundation soil settlement and welding quality reason, occur when removing down conductor and tower body tie point, because of cause down conductor and the earthing pole buried underground or ring grounded screen sealing-off by External Force Acting or remove be completed after situation about cannot recover occur, the potential safety hazard larger to line thunder protection existence.Adopt when traditional three electrode method or split-core type meter method test stake resistance and except needing, the tie point at grounded screen and each tower angle of shaft tower tower body is opened, re-use after wire is all connected and just can test after also needing four radiation earthing poles to disconnect with tower body when running into the grounded screen test that radial pattern earthing pole forms, because the spacing at four tower angles is excessive, when running into the column foot crossing over river or valley, rice up to a hundred can be reached when tower angular separation is maximum, cause the connecting line of earthing pole long, bring very large difficulty to on-the-spot test personnel, cause testing efficiency low.

Summary of the invention

The present invention is directed to above-mentioned problems of the prior art, provide a kind of pole tower ground resistance measurement mechanism exempting to tear open down conductor, solve the inefficient problem of prior art pilot scale.

Another object of the present invention is to provide a kind of measuring method of exempting to tear open the pole tower ground resistance measurement mechanism of down conductor.

Technical scheme of the present invention is as follows:

Control module connects supply module and measuring and protecting circuit, and supply module connects inversion changing frequency power supply and Current injection points successively, and Current injection points connects current measurement circuit and shaft tower column foot; Measuring and protecting circuit connects tension measuring circuit and current measurement circuit, and current measurement circuit connects main frame sending module and main frame receiver module, and main frame sending module is connected current sensor with main frame receiver module, and current sensor connects shaft tower column foot.

Described control unit is connected with display screen, keyboard and printer.

Described current sensor comprises No. 1 current sensor, No. 2 current sensors, No. 3 current sensors and No. 4 current sensors.

No. 1 described current sensor, No. 2 current sensors, No. 3 current sensors and No. 4 current sensors are connected to sending module and receiver module.

Measuring method of the present invention comprises the steps:

Arrange current pole and voltage pole is required according to three electrode method, the optional position selecting tower body is reference point, No. 1 current sensor, No. 2 current sensors, No. 3 current sensors and No. 4 current sensors are wound around 4 the column foot down conductor places being arranged on shaft tower respectively, control module detects the instruction of input through keyboard, control supply module simultaneously and output to inversion changing frequency power supply, reference point is flowed into through inversion changing frequency power supply, reference point electric current flows to Current injection points by the earth, and Current injection points and inversion changing frequency power supply are connected to form loop, tension measuring circuit obtains reference point and the direct magnitude of voltage of reference voltage simultaneously, control module is by the current transformer transmission enabling signal of main frame sending module to four column foots, for ensureing the real-time measured, four receiver modules receive enabling signal simultaneously and start sampling, within 3 seconds, post-sampling terminates, the sample signal discontinuity that obtains of current transformer sends sampled data to main frame receiver module, sending order is that the 4th second No. 1 current transformer sends successively, within 5th second, No. 2 current transformers send, within 6th second, No. 3 current transformers send, within 7th second, No. 4 current transformers send, under the continuity of being separated by a second sends and can ensure similar frequency bands, signal can accurately identify tower angular dependence, avoid multiband to send the interference causing signal simultaneously, current measurement circuit obtains by flexible current pincers the current value flowing through four column foots, and calculate resistance value according to Ohm law R=U/I, result of calculation is shown to display screen by control module.

Advantageous effect of the present invention is as follows:

The present invention can when not disassembling down conductor, reduces earthing pole connecting line simultaneously, easily and fast, accurately can test and have single, two and above down conductor overhead line structures grounding resistance, increase work efficiency and reduce testing cost.

Small current measurement antijamming capability of the present invention is strong, shows that the power of instrument built-in DC/AC inverter is selected, the degree of purity of short-circuit protection, out-put supply frequency, digital filtering process, current sampling circuit, man-machine interface are friendly, each cell isolation measure.

Measuring object of the present invention has alternative, and user directly can test single column foot impedance, also can measure the parallel impedance of four column foots; Both the impedance ground of column foot natural grounding be can measure, resistance or the parallel resistance of the two of column foot artificial earthing downlead also can have been measured.

The present invention can reduce the wiring difficulty of test site, increases work efficiency, and brings advanced means of testing to pole tower ground resistance test job, greatly can simplify hard work and cable wire management work that on-the-spot test in the past needs to remove down conductor.

The present invention need not tear/recover tower grounding downlead open, thus saves time; Use manpower and material resources sparingly, save testing cost; Sampled signal wireless transmission, reduces on-the-spot connection and workload; Sampled signal wireless transmission, and there is real-time and continuity, test data is accurate.

Accompanying drawing explanation

Fig. 1 tower grounding tester theory diagram.

Fig. 2 pole tower ground resistance proving installation wiring diagram.

In Fig. 1, 1, control module, 2, display screen, 3, keyboard, 4, printer, 5, supply module, 6, measuring and protecting circuit, 7, tension measuring circuit, 8, current measurement circuit, 9, main frame sending module, 10, main frame receiver module, 11, inversion changing frequency power supply, 12, Current injection points, 13, No. 1 current sensor, 14, No. 2 current sensors, 15, No. 3 current sensors, 16, No. 4 current sensors, 17, shaft tower, 18, No. 1 sending module, 19, No. 2 sending modules, 20, No. 3 sending modules, 21, No. 4 sending modules, 22, No. 1 receiver module, 23, No. 2 receiver modules, 24, No. 3 receiver modules, 25, No. 4 receiver modules, A-D, shaft tower column foot.

In Fig. 2,26, measurement mechanism, 27, current transformer, 28, insertion point, electric current pole, 29, voltage pole insertion point.

Embodiment

In order to type of the present invention is realized technological means, using method, apparatus structure is convenient understands, combine and illustrate, set forth further.

As shown in Figure 1-2, control module 1 connects display screen 2, keyboard 3, printer 4, supply module 5 and measuring and protecting circuit 6, and supply module connects inversion changing frequency power supply 11 and Current injection points 12 successively, and Current injection points connects current measurement circuit 8 and shaft tower column foot; Measuring and protecting circuit 6 connects tension measuring circuit 7 and current measurement circuit 8; current measurement circuit connects main frame sending module 9 and main frame receiver module 10; main frame sending module is connected current sensor with main frame receiver module, and current sensor connects shaft tower column foot A-D.

Described current sensor comprises No. 1 current sensor 13, No. 2 current sensors 14, No. 3 current sensors 15 and No. 4 current sensors 16; No. 1 described current sensor connects No. 1 sending module 18 and No. 1 receiver module 22, No. 2 current sensors connect No. 2 sending modules 19 and No. 2 receiver modules 23, No. 3 current sensors connect No. 3 sending modules 20 and No. 3 receiver modules 24, No. 4 current sensors connect No. 4 sending modules 21 and No. 4 receiver modules 25.

Multi-functionally exempt from pole tower ground resistance proving installation wiring diagram of taking out stitches, (straight line 0.618 or 30 ° of angle-off sets) arrange current pole and voltage pole is required according to three electrode method, the optional position selecting tower body is reference point, electric current pole C2, voltage pole P2 are received on reference point G, electric current pole C1 connects electric current pole, and voltage pole P1 connects voltage pole.The long rod iron for 50cm, diameter 2cm of every root electrode, it is in the ground of 3 ~ 4d that electric current pole C1 is inserted in apart from tower angle maximum diagonal distance (d), is connected by the extreme mouth C1 of wire and the electric current of device.Voltage pole P1 insertion position: 30 ° of angle-off set-voltage pole P1 are inserted in electric current pole C1 apart from the ground of shaft tower distance about 1 times, and current line becomes more than 30 ° angles with pressure-wire; Be connected with the voltage pole port P1 of measurement mechanism by wire.Use 4 high precision flexible current mutual inductors, be wound around 4 the column foot down conductor places being arranged on shaft tower respectively, tester and flexible current mutual inductor communication rely on wireless transmission and receiving module to complete.

The instruction that keyboard 3 inputs is detected by control module 1, control supply module 5 simultaneously and output to inversion changing frequency power supply 11, flow into reference point G, reference point G electric current through inversion changing frequency power supply and flow to Current injection points 12 by the earth, Current injection points and inversion changing frequency power supply 11 are connected to form loop.Voltage sample circuit obtains reference point G and the direct magnitude of voltage of reference voltage simultaneously, control module 1 is by the current transformer transmission enabling signal of main frame sending module 9 to four tower angles, for ensureing the real-time measured, four receiving ends receive enabling signal simultaneously and start sampling, within 3 seconds, post-sampling terminates, the sample signal discontinuity that obtains of current transformer sends sampled data to main frame receiver module, sending order is that the 4th second No. 1 current transformer sends successively, within 5th second, No. 2 current transformers send, within 6th second, No. 3 current transformers send, within 7th second, No. 4 current transformers send, under the continuity of being separated by a second sends and can ensure similar frequency bands, signal can accurately identify tower angular dependence, avoid multiband to send the interference causing signal simultaneously.Current sampling circuit obtains by flexible current pincers the current value flowing through four tower angles, calculates resistance value according to Ohm law R=U/I.Result of calculation is shown to display screen by control module.

Flexible current mutual inductor sampling obtains voltage signal, because flexible current mutual inductor is hollow Luo-coil, sampled signal is faint especially, further process is done by amplifying circuit, voltage signal integration after amplification obtains current signal, phase calibration circuitry does phase place adjustment to current signal, and the signal after calibration relies on wireless sending module to be gone out by digital signal transmission through over-sampling circuit and Fourier transform.

Printer can select data-printing according to display screen order instruction.

This device adopts non-power-frequency current measuring technology to realize exempting to tear down conductor open and measures pole tower ground resistance.

This device increases wireless transmission and receiver module, decreases field wiring, enhances practical, improve work efficiency.

The present invention utilizes alien frequencies Anti-Jamming Technique, in conjunction with traditional V.A. method and split-core type meter method measuring principle, non-power-frequency current is injected at shaft tower tower body and far-end electric current pole, the flexible wideband Luo-coil of open type is used to be wrapped in non-power-frequency current tower grounding downlead being measured each tower corner-of-delta grounding downlead, Measurement bandwidth scope is 40Hz-5kHz, for the voltage U measured sand electric current I s(I a+ I b+ I c+ I d) signal synchronously samples respectively, and carry out dispersion Fourier expansion and digital filtering, remove power frequency 50Hz and high-frequency interferencing signal, by measurement mechanism, spectrum analysis is done to electric current, voltage signal, fundametal compoment is wherein separated, adopts ohm law computing method to obtain the stake resistance of tested shaft tower.The instrument of exempting from dismounting ground wire measurement circuit pole tower ground resistance developed can easily be measured the overhead line structures stake resistance of any shape, selective measurement can also be carried out in the ground connection parallel network of electric tower, 1 or 4 current sensors (Luo-coil) are placed in below tower grounding downlead and tower body tie point or (comprise Concrete in Natural foundation grounding pole) around shaft tower feet, so just can measure the stake resistance of shaft tower accurately.And measure after ground lead does not need to be disconnected, by short distance microwave communication mode, by Luo-coil, the electric current measured in each bar down conductor is sent on Test Host, there is the impact can imitated and avoid earth method, decrease earthing pole connecting line simultaneously.

The chargeable power supply module of the present invention is connected with inversion changing frequency power supply, for providing power supply to test; Host computer control testing power supply is to the Injection Current amplitude of shaft tower and electric current pole and voltage pole signal sampling; Flexible current mutual inductor is wrapped in the down conductor at each tower angle, for detecting the non-power-frequency current of the down conductor flowing through each tower angle, by wireless, test data is sent back to Test Host; By main frame, synchrodata process and conversion are carried out to the electric current of each down conductor in tower angle and voltage pole voltage; Its voltage input end of display device main frame is connected with control module and communication unit, the synchronized sampling of control voltage, current signal, main frame comprises a display and a keyboard, display is used for display measurement data, Keyboard Control injects measuring current, synchronous reading sampled data, calculates test result.

Current sampling signal of the present invention is analyzed after filtering, remove the power frequency composition in circuit, carry out dispersion Fourier expansion and carry out AD conversion obtaining digital signal, the digital signal that process obtains is with the transmission of wireless signals of the mode of Transistor-Transistor Logic level by 315kHz, the host terminal of equipment is furnished with signal receiving module, and the signal that this module receives directly is used as test result calculations.

Claims (5)

1. exempt from the pole tower ground resistance measurement mechanism tearing down conductor open for one kind, it is characterized in that control module connects supply module and measuring and protecting circuit, supply module connects inversion changing frequency power supply and Current injection points successively, and Current injection points connects current measurement circuit and shaft tower column foot; Measuring and protecting circuit connects tension measuring circuit and current measurement circuit, and current measurement circuit connects main frame sending module and main frame receiver module, and main frame sending module is connected current sensor with main frame receiver module, and current sensor connects shaft tower column foot.
2. according to claim 1ly a kind ofly exempt from the pole tower ground resistance measurement mechanism tearing down conductor open, it is characterized in that described control unit is connected with display screen, keyboard and printer.
3. according to claim 1ly a kind ofly exempt from the pole tower ground resistance measurement mechanism tearing down conductor open, it is characterized in that described current sensor comprises No. 1 current sensor, No. 2 current sensors, No. 3 current sensors and No. 4 current sensors.
4. according to claim 3ly a kind ofly exempt from the pole tower ground resistance measurement mechanism tearing down conductor open, it is characterized in that No. 1 described current sensor, No. 2 current sensors, No. 3 current sensors and No. 4 current sensors are connected to sending module and receiver module.
5. a kind of measuring method exempting from the pole tower ground resistance measurement mechanism tearing down conductor open according to claim 1, is characterized in that comprising the steps:
Arrange current pole and voltage pole is required according to three electrode method, the optional position selecting tower body is reference point, No. 1 current sensor, No. 2 current sensors, No. 3 current sensors and No. 4 current sensors are wound around 4 the column foot down conductor places being arranged on shaft tower respectively, control module detects the instruction of input through keyboard, control supply module simultaneously and output to inversion changing frequency power supply, reference point is flowed into through inversion changing frequency power supply, reference point electric current flows to Current injection points by the earth, and Current injection points and inversion changing frequency power supply are connected to form loop, tension measuring circuit obtains reference point and the direct magnitude of voltage of reference voltage simultaneously, control module is by the current transformer transmission enabling signal of main frame sending module to four column foots, for ensureing the real-time measured, four receiver modules receive enabling signal simultaneously and start sampling, within 3 seconds, post-sampling terminates, the sample signal discontinuity that obtains of current transformer sends sampled data to main frame receiver module, sending order is that the 4th second No. 1 current transformer sends successively, within 5th second, No. 2 current transformers send, within 6th second, No. 3 current transformers send, within 7th second, No. 4 current transformers send, under the continuity of being separated by a second sends and can ensure similar frequency bands, signal can accurately identify tower angular dependence, avoid multiband to send the interference causing signal simultaneously, current measurement circuit obtains the current value flowing through four column foots, according to Ohm law by flexible current pincers u/I calculates resistance value, and result of calculation is shown to display screen by control module.
CN201510503724.2A 2015-08-17 2015-08-17 Tower grounding resistance measurement apparatus without dismounting of grounding down lead, and measurement method thereof CN105021897A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105891606A (en) * 2016-06-27 2016-08-24 国网甘肃省电力公司白银供电公司 Device for testing tower grounding resistance through disassembly-free ground lead
CN106093589A (en) * 2016-08-09 2016-11-09 国网重庆市电力公司南岸供电分公司 A kind of pole tower ground resistance Accurate measurement and device
CN106771639A (en) * 2016-12-14 2017-05-31 国家电网公司 High pressure pole tower ground resistance on-line monitoring system
CN107782975A (en) * 2017-09-19 2018-03-09 山东建筑大学 Distributed grounding resistance detection system and detection method based on radio signal source
CN108896472A (en) * 2018-05-14 2018-11-27 国网湖南省电力有限公司 Overhead transmission line shaft tower is grounded corrosion detecting method

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CN104535844A (en) * 2015-01-20 2015-04-22 国网辽宁省电力有限公司抚顺供电公司 Method for testing grounding resistance of tower by using disassembly-free down conductor
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
CN204903655U (en) * 2015-08-17 2015-12-23 国网辽宁省电力有限公司抚顺供电公司 Tower grounding resistance measurement device of disconnect ground downlead exempts from

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CN1158425A (en) * 1996-11-26 1997-09-03 山西省忻州地区电业局 Release-free electric cable tower ground resistance testing method and device
CN101266270A (en) * 2008-05-06 2008-09-17 重庆大学 Pile foundation tower-footing impedance measuring apparatus and its method
CN201780335U (en) * 2010-01-04 2011-03-30 广东电网公司广州供电局 Ground resistance detecting device of overhead transmission line pole tower
CN102680798A (en) * 2012-02-28 2012-09-19 山东建筑大学 Online measurement method and device for grounding resistor of rod tower
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105891606A (en) * 2016-06-27 2016-08-24 国网甘肃省电力公司白银供电公司 Device for testing tower grounding resistance through disassembly-free ground lead
CN106093589A (en) * 2016-08-09 2016-11-09 国网重庆市电力公司南岸供电分公司 A kind of pole tower ground resistance Accurate measurement and device
CN106093589B (en) * 2016-08-09 2018-09-18 国网重庆市电力公司南岸供电分公司 A kind of pole tower ground resistance Accurate measurement and device
CN106771639A (en) * 2016-12-14 2017-05-31 国家电网公司 High pressure pole tower ground resistance on-line monitoring system
CN106771639B (en) * 2016-12-14 2019-11-15 国家电网有限公司 High pressure pole tower ground resistance on-line monitoring system
CN107782975A (en) * 2017-09-19 2018-03-09 山东建筑大学 Distributed grounding resistance detection system and detection method based on radio signal source
CN107782975B (en) * 2017-09-19 2019-11-12 山东建筑大学 Distributed grounding resistance detection system and detection method based on radio signal source
CN108896472A (en) * 2018-05-14 2018-11-27 国网湖南省电力有限公司 Overhead transmission line shaft tower is grounded corrosion detecting method

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