CN100397087C - Pole tower earthing resistance quick testing method without unfastening wire and device - Google Patents

Abstract

The present invention relates to a quick testing method without unfastening wires for a tower earthing resistance and a device of the quick testing method without unfastening wires. An embed-meter method is adopted and a plurality of earthing down leads of a tower are not loosened. Forcipated voltage mutual inductors, PT for short, the number of which is the same as the number of the earthing down leads of the tower, and forcipated current mutual inductors, CT for short, are used so that the forcipated PT and CT respectively clamp all the earthing leading down leads, or belt-shaped voltage mutual inductors, PT for short, and belt-shaped current mutual inductors, CT for short are used so that the belt-shaped PT and CT enclose the whole iron tower. Through filtering processing and data analysis of the measured voltage and current signals, the real and the imaginary parts of the fundamental components of the current and the voltage signals are obtained. A specific voltage dropping computation method is adopted to obtain the earthing resistance of the measured tower. The present invention can correctly and quickly measure the resistance of a tower with one, two or more than two earthing down leads under the condition of not loosening the earthing down leads, enhance the efficiency of the measuring work and decrease the measuring cost.

Description

Pole tower earthing resistance quick testing method without unfastening wire and device

Technical field

The invention belongs to the High-Voltage Technology field of power science, relate to a kind of transmission tower ground resistance measurement method and device, particularly a kind of pole tower earthing resistance quick testing method without unfastening wire and device, it is used to lightning conducter is the security maintenance technical elements of the transmission tower of aerial earth wire.

Background technology

The transmission tower grounding resistance is significant for reducing lightning outage rate, reach in service before transmission tower comes into operation, its stake resistance of periodic measurement is particularly important, and power industry standard DL/T 596-1996 " power equipment preventive trial rules " once did this and appears explicit stipulation.Therefore the grounding resistance of measuring transmission tower accurately, quickly and easily is that whether qualified its earthed system of check is and propose the important channel and the means of corresponding rectification scheme.Known to the applicant, the measurement to the transmission tower stake resistance at present mainly contains two kinds of methods, promptly based on the three electrode method and the split-core type meter method of pressure drop principle.Wherein the typical instrument of split-core type meter method has French CA6411 type earth resistance tester, only need during test that jaw is clamped a down conductor and can obtain grounding resistance, but other down conductors of shaft tower must be untied, otherwise measured value is the loop resistance that downlead and grounding body form, in addition, because the mutual inductance of installation of dual lightning wires and the internal resistance that self can not ignore have brought error to actual measurement.Present pole tower ground resistance is measured, and maximum drawback is the Project Realization difficulty, situation about running into usually, and when two and above down conductor, the nut that in measurement, generally all must use the electric welding machine unsolder to be welded; Perhaps turn on nut.3～4 people's measurement group, can only survey 4～5 basic shaft towers a working day at most, and efficiency of measurement is extremely low, and labour intensity is big, also may twist off bolt, stripped thread, even can not recover drawbacks such as ground connection.According to " preventive trial rules " promulgated by the ministries or commissions of the Central Government regulation, powerline pole tower ground resistance was all measured once in per 4 years.By present test present situation, test 5 bases every group of every day, every group 3 people uses one of automobile machine-team, can calculate every basic testing expense thus and be 160 yuan ((100 yuan/people. sky * 3 people * 1 day+500 yuan/machine-team * 1 machine-team)/5 bases).If a 110kV that electric company has jurisdiction over and above electric power line pole tower amount to 5000 bases, all survey 1000 days/group of need, about 800,000 yuan of expense.

Summary of the invention

The objective of the invention is, at the defective on the existing pole tower ground resistance measurement method, pole tower earthing resistance quick testing method without unfastening wire and device are proposed, it be a kind of can be under the situation of not untiing many down conductors, correct method and the device of measuring the transmission tower grounding resistance apace, it can improve the work efficiency of measurement, reduces and measures cost.

Technical solution of the present invention is, a kind of pole tower earthing resistance quick testing method without unfastening wire, adopt the split-core type meter method, measured voltage, current signal is through Filtering Processing and data analysis, obtain the real part and the imaginary part of the fundametal compoment of current signal and voltage signal, adopt the specific pressure drop computing method to obtain the stake resistance of tested shaft tower, it is characterized in that: use the pincerlike voltage transformer (VT) identical to be called for short PT and split core type current transformer abbreviation CT with tower grounding downlead radical, do not understand the many down conductors of tower of starting, with pincerlike PT, CT clamps all down conductors respectively; Or, use band shape voltage transformer (VT) to be called for short PT and to be with the shape current transformer to be called for short CT, do not understand the tower down conductor of starting, will be with shape PT, CT to surround whole iron tower; The function of the measuring voltage of providing is provided pincerlike or band shape PT, pincerlike or band shape CT has the function of measuring electric current, sample respectively for measuring voltage U and electric current I signal, and simulate trap and bandpass filtering, remove power frequency and high-frequency interferencing signal, only allow measuring-signal to pass through, by the Frequency Synchronization of measurement mechanism to voltage and current signals sampling and power source, electric current, voltage signal done the spectrum analysis of widening window, fundametal compoment is wherein separated, further to remove interference components.

Above-mentioned pole tower earthing resistance quick testing method without unfastening wire, the specific pressure drop computing method of employing are to establish R _gBe a certain pole tower ground resistance value, each down conductor has the connection resistance R ₁, R ₂... R _n,, introduce measuring error and be made as Z for having only a down conductor or using the situation of being with shape PT and CT _E=R _E+ jX _E, the stake resistance measured value is R _g'=R ₁+ R _g+ Z _E, stake resistance calculates and adopts following formula:

$R_g^{\′}=\mathrm{Re}({\stackrel{\·}{U}}_1/{\stackrel{\·}{I}}_1)$

Wherein,

Be down conductor test voltage value, Be the current value in down conductor loop, R ' _gFor containing the grounding resistance measurement value of error, its error is by R ₁And Z _ETwo parts are formed, and Re represents plural number is got real part, and this moment is approximate thinks R _gBe R _gFor situation, introduce measuring error and be made as Z with two or two above down conductors _E=R _E+ jX _E, the stake resistance measured value is R _g=R _g+ Z _E, its error only contains Z _EPart connects resistance R ₁, R ₂..., R _nAccurately solve from following equation, stake resistance calculates and adopts following formula:

Wherein

Be each down conductor test voltage value,

Be the current value by each down conductor loop, above-mentioned matrix does not have unique solution, need carry out the second time and measure, only to R ₁Power supply is provided, obtains following additional equation:

${\stackrel{\·}{U}}_1-{\stackrel{\·}{I}}_1^{\′}{R}_1=({\stackrel{\·}{I}}_1^{\′}+{\stackrel{\·}{I}}_2^{\′}+\·\·\·+{\stackrel{\·}{I}}_n^{\′}){R_g}^{\′}$

Get by above-mentioned two equations:

For obtaining above-mentioned equation unique solution,, must satisfy following formula according to the linear algebra theory:

$\frac{{\stackrel{\·}{I}}_1}{{\stackrel{\·}{I}}_1^{\′}}\≠\frac{{\stackrel{\·}{I}}_1+{\stackrel{\·}{I}}_2+\·\·\·{\stackrel{\·}{I}}_n}{{\stackrel{\·}{I}}_1^{\′}+{\stackrel{\·}{I}}_2^{\′}+\·\·\·{\stackrel{\·}{I}}_n^{\′}}$

For guaranteeing the following formula establishment, judge earlier whether the data that collect satisfy following formula, if be false, then will

The value change, and measure once more, till following formula was set up, solving an equation then obtained R _g'; The grounding resistance measurement value R that obtains under above-mentioned two kinds of situations _g' all contain error Z _ESo, need be revised, mainly be pure resistive characteristics at the pole tower ground resistance value, only need consider during correction pole tower ground resistance R _g' real part correction get final product and Z _EReal part be R _E, correction formula is as follows:

R _E＝-6+0.95lnf+2.3R _d+0.105ln(R _gv) ²+1.75lnR _gv

Wherein f is for measuring supply frequency, R _GvBe the average stake resistance of test line shaft tower, R _dBe the resistance value of every span lightning conducter, obtain revised grounding resistance thus and be:

R _g＝Re(R _g′)-R _E。

The present invention adopts exempts to separate line pole tower ground resistance rapid measurement device, it is characterized in that: be made up of a plurality of pincerlike voltage transformer (VT) or a banded voltage transformer (VT) (being called for short PT) 14, a plurality of split core type current transformer or banded current transformer (being called for short CT) 15 and pole tower ground resistance tacheometer 16; The pole tower ground resistance tacheometer is by power source module 1, multi-way switch module 2, I/V modular converter 3, filtration module 4, program control amplification module 5, A/D modular converter 6, Single Chip Microcomputer (SCM) system 7, sinusoidal wave module 8, the Synchronous Sampling Pulse module 9 of taking place, and LCD MODULE 10, communication module 11, panel and Keyboard Control module 12, battery and charging module 13 are formed.Power supply is used in power source module 1 generator and test, by voltage output end mouth U _NhAnd U _NlVoltage signal is delivered to a plurality of pincerlike voltage transformer (VT) (being called for short PT) or a banded voltage transformer (VT) 14; The sinusoidal wave module 8 that takes place connects power source module 1 input, and battery and charging module 13 connect power source module 1 feeder ear; The input end of the output termination Synchronous Sampling Pulse module 9 of power source module 1, and an input end of multi-way switch module 2; A plurality of split core type current transformers (being called for short pincerlike CT) or a banded current transformer 15 are by electric current port I _NhAnd I _NlCurrent signal is sent into I/V modular converter 3, and the output of I/V modular converter 3 connects another input end of multi-way switch module 2; The output of multi-way switch module 2 connects filtration module 4 input ends, filtration module 4 outputs connect the input end of program control amplification module 5, the output of program control amplification module 5 connects A/D modular converter 6 one input ends, and the output of Synchronous Sampling Pulse module 9 connects A/D modular converter 6 another input ends; News module 11, Single Chip Microcomputer (SCM) system 7, panel and Keyboard Control module 12 are connected in the output of A/D modular converter 6; Single Chip Microcomputer (SCM) system 7 connects by control bus and address/data bus and Synchronous Sampling Pulse module 9 LCD MODULE 10, communication module 11, panel and Keyboard Control module 12, battery and charging module 13.

Above-mentionedly exempt to separate line pole tower ground resistance rapid measurement device, it is characterized in that, the measurement power supply of 0.5V～5V/1～5W is provided after described sinusoidal waveform generation module 8 output signals are amplified through power source module 1.

Above-mentionedly exempt to separate line pole tower ground resistance rapid measurement device, it is characterized in that filtration module 4 is composed in series by 50Hz quadravalence analogue notch 17 and quadravalence analog band-pass filter 18.

Adopt the present invention, can be under the situation of not untiing down conductor, to measure correctly, fast and have single, two and above down conductor pole tower ground resistance value, it can significantly improve efficiency of measurement, reduces and measures cost.Apparatus of the present invention degree of intelligence height, storage or transferring data are convenient; Low in energy consumption, but the working power recharge of outfit uses; Can also find simultaneously the contact conduction property problem of down conductor, when transmission line of electricity was normally maked an inspection tour, the tour personnel can carry apparatus and finish test assignment.If a 110kV that electric company has jurisdiction over and above electric power line pole tower amount to 5000 bases, use every group of the present invention can survey 100 bases at least in one day, every basic test fee is only with being 8 yuan, surveys one time need 50 days/organize, surplus the expense about 4 ten thousand yuan, can save surplus the testing expense 70 ten thousand yuan.

Description of drawings

Fig. 1, the transmission line of electricity synoptic diagram

Fig. 2 adopts pincerlike PT, CT instrumentation plan

Fig. 3 adopts band shape PT, CT instrumentation plan

Fig. 4 adopts pincerlike PT, CT measuring principle figure

Fig. 5 adopts pincerlike PT, CT, measures equivalent circuit diagram when having only a down conductor

Fig. 6 adopts pincerlike PT, CT, measures equivalent circuit diagram when two and above down conductor are arranged for the first time

Fig. 7 adopts pincerlike PT, CT, measures equivalent circuit diagram when two and above down conductor are arranged for the second time

Fig. 8 adopts band shape PT, CT to measure equivalent circuit diagram

Fig. 9, pole tower ground resistance tacheometer 16 circuit block diagrams

Figure 10, the circuit block diagram of filtration module 4

Figure 11 exempts to separate line pole tower ground resistance rapid measurement device field wiring figure

Among the figure, 1 power source module, 2 multi-way switch modules, the 3I/V modular converter, 4 filtration modules, 5 program control amplification modules, the 6A/D modular converter, 7 Single Chip Microcomputer (SCM) system, the 8 sinusoidal wave modules that take place, 9 Synchronous Sampling Pulse modules, 10 LCD MODULE, 11 communication modules, 12 panels and Keyboard Control module, 13 batteries and charging module, 14 pincerlike voltage transformer (VT) or banded voltage transformer (VT) (being called for short PT), 15 split core type current transformers or banded current transformer (being called for short CT), 16 pole tower ground resistance tacheometers, 1750Hz quadravalence analogue notch, 18 quadravalence analog band-pass filters.

Embodiment

Below in conjunction with accompanying drawing, elaborate implementation method of the present invention.

Fig. 1 is the transmission line of electricity synoptic diagram, is that the band lightning conducter is the transmission tower of aerial earth wire, according to basic conception of the present invention, adopts following two kinds of technical approach to measure:

1) Fig. 2 is for adopting pincerlike PT, CT instrumentation plan, use pincerlike voltage transformer (VT) (be called for short pincerlike PT) identical and split core type current transformer (being called for short pincerlike CT) with tower grounding downlead radical, do not understand the tower down conductor of starting, pincerlike PT, CT are clamped all down conductors respectively; Perhaps,

2) Fig. 3 uses band shape voltage transformer (VT) to be called for short (band shape PT) and band shape current transformer (being called for short band shape CT) for adopting band shape PT, CT instrumentation plan, does not understand the tower down conductor of starting, and will be with shape PT, CT to surround whole iron tower;

Use above-mentioned dual mode to measure, measured voltage, current signal is through Filtering Processing and data analysis, obtain the real part and the imaginary part of the fundametal compoment of current signal and voltage signal, adopt specific pressure drop to calculate the stake resistance of tested shaft tower, but the function of measuring voltage of providing and measuring voltage is provided pincerlike or band shape PT, pincerlike or band shape CT has the function of measuring electric current, sample respectively for measuring voltage U and electric current I signal, and simulate trap and bandpass filtering, remove power frequency and high-frequency interferencing signal, only allow measuring-signal to pass through, by the Frequency Synchronization of measurement mechanism to voltage and current signals sampling and power source, to electric current, the spectrum analysis that the voltage signal work is widened window is separated fundametal compoment wherein, further to remove interference components.

Fig. 4 adopts pincerlike PT, CT measuring principle figure, all is connected to a pair of pincerlike PT, CT on every down conductor on a certain shaft tower, and adopting the specific pressure drop computing method is to establish R _gBe a pole tower ground resistance value, each down conductor of retinal rod tower is different with the earth mat method of attachment or connect appearance corrosion and other nonmetal situations that contacts, and equivalence is looked each down conductor and had the connection resistance R ₁, R ₂... R _n

Fig. 5 measures equivalent circuit diagram when having only a down conductor, consider that the lightning conducter on the transmission tower is that aerial earth wire is to measuring the influence in loop, introducing measuring error Z _E=R _E+ jX _E, simplify to be expressed as making R _g=R ₁+ R _g+ Z _E, stake resistance calculates and adopts following formula,

$R_g^{\′}=\mathrm{Re}({\stackrel{\·}{U}}_1/{\stackrel{\·}{I}}_1)$

Wherein,

Be down conductor test voltage value,

Be the current value in down conductor loop, R ' _gFor containing the grounding resistance measurement value of error, Re represents plural number is got real part.

Fig. 6 measures equivalent circuit diagram for the first time when two above down conductors are arranged, the lightning conducter on the same consideration transmission tower be aerial earth wire to measuring the influence in loop, introduce measuring error Z _E=R _E+ jX _E,, make R for simplifying _g=R _g+ Z _E, can obtain by measuring equivalent circuit Fig. 6 structure:

$\left\{\begin{array}{c}{\stackrel{\·}{U}}_1-{\stackrel{\·}{I}}_1{R}_1=({\stackrel{\·}{I}}_1+{\stackrel{\·}{I}}_2+\·\·{\stackrel{\·}{I}}_n){R_g}^{\′}\\ {\stackrel{\·}{U}}_2-{\stackrel{\·}{I}}_2{R}_2({\stackrel{\·}{I}}_1+{\stackrel{\·}{I}}_2+\·\·{\stackrel{\·}{I}}_n){R_g}^{\′}\\ \·\\ \·\\ \·\\ {\stackrel{\·}{U}}_n-{\stackrel{\·}{I}}_n{R}_n=({\stackrel{\·}{I}}_1+{\stackrel{\·}{I}}_2+\·\·\·{\stackrel{\·}{I}}_n){R_g}^{\′}\end{array}\right.$

Can get by following formula:

Above-mentioned matrix equation can't provide unique solution, therefore, must replenish an equation to it; Carrying out the second time measures.Fig. 7 measures equivalent circuit diagram when being two above down conductors for the second time, only to R ₁Power supply is provided, obtains following additional equation:

${\stackrel{\·}{U}}_1^{\′}-{\stackrel{\·}{I}}_1^{\′}{R}_1=({\stackrel{\·}{I}}_1^{\′}+{\stackrel{\·}{I}}_2^{\′}+\·\·\·+{\stackrel{\·}{I}}_n^{\′}){R_g}^{\′}$

Can get by above-mentioned two equations:

For obtaining above-mentioned equation unique solution,, must satisfy following formula according to the linear algebra theory:

$\frac{{\stackrel{\·}{I}}_1}{{\stackrel{\·}{I}}_1^{\′}}\≠\frac{{\stackrel{\·}{I}}_1+{\stackrel{\·}{I}}_2+\·\·\·{\stackrel{\·}{I}}_n}{{\stackrel{\·}{I}}_1^{\′}+{\stackrel{\·}{I}}_2^{\′}+\·\·\·{\stackrel{\·}{I}}_n^{\′}}$

For following formula is set up, should judge earlier whether the data that collect satisfy following formula, if be false, then will

The value change, and measure once more, till following formula was set up, solving an equation then obtained R _g', the invalid probability of following formula is minimum in the actual measurement.

For above-mentioned shaft tower with one or more down conductors, the actual R that records ₁, R ₂... R _nAnd

And non-pure resistance, but for the tower grounding system, because grounding body is less, grounding resistance R _gGenerally be pure resistive, reaction component can be ignored; Under the situation of not considering reactance, R ₁, R ₂... R _n, measured value be accurately; And actual grounding resistance

With measured value

Value of real part differ bigger, produce error R thus _E, error R _EBe corrected the convergence that key is that it has; At the situation of lightning conducter graded insulation, the higher measurement power supply of frequency surely belongs to first-selection; Lightning conducter electric conductivity is good more, and its steady-state error value is just little comparatively speaking, and steady-state error value and conductor resistance rate are approximated to direct ratio; Under the normal ground connection situation, the average stake resistance that is parallel to tested pole tower ground resistance also has influence to measured value, normal average stake resistance is relevant with the soil resistivity of design of transmission line of electricity grounding body and locality, and circuit integral ground level is good, and its steady-state error is just little.Measured value need be revised, and correction formula is as follows:

R _E＝-6+0.95lnf+2.3R _d+0.105ln(R _v) ²+1.7lnR _v

Wherein f is for measuring supply frequency, R _vBe the average stake resistance of test line shaft tower under the normal condition, R _dBe every span lightning conducter resistance value.

Obtaining revised measured value thus is:

R _g＝Re(R _g′)-R _E

Fig. 8 adopts band shape PT, CT to measure equivalent circuit diagram, adopts band shape CT, PT with shaft tower and some down conductors whole " blocking ".Do not open down conductor, do not increasing again under the condition of auxiliary electrode, can quick and precisely measure the stake resistance of shaft tower.Provide the function of voltage source because band shape PT has for measuring the loop, band shape CT has the function of measuring loop current.The multipoint earthing downlead of same earthed system surrounds by banded PT and CT, establishes R _gBe the pole tower ground resistance value, because each down conductor is different with the earth mat method of attachment, perhaps corroding and other non-situations that fully contacts appears in the junction, can equivalence looks it and has the connection resistance R ₁, R ₂, R _n, because the transmission tower lightning conducter is that aerial earth wire is to measuring the influence in loop, introducing measuring error Z _E=R _E+ jX _E, generally connect resistance R ₁, R ₂..., R _nLess than 0.1 Ω, can ignore, can directly obtain this moment ${R_g}^{\′}=\mathrm{Re}(\stackrel{\·}{U}/\stackrel{\·}{I}),$ Obtain final measured value R through aforementioned error correction formula then _g=Re (R _g')-R _EDuring for the situation of having only a down conductor or use band shape PT and CT, if revise back R _gBe worth excessively, it is defective to judge ground connection, or the down conductor loose contact, or grounding body is defective; For situation, if R with two or two above down conductors ₁, R ₃..., R _nPromptly learn the down conductor loose contact greater than 0.1 Ω.

The present invention adopts exempts to separate line pole tower ground resistance rapid measurement device, by a plurality of pincerlike voltage transformer (VT) or a banded voltage transformer (VT) (being called for short PT) 14, a plurality of split core type current transformers or a banded current transformer (abbreviation CT) 15 and pole tower ground resistance tacheometer 16 compositions, Fig. 9 is pole tower ground resistance tacheometer 16 circuit block diagrams, pole tower ground resistance tacheometer 16 is by power source module 1, multi-way switch module 2, I/V modular converter 3, filtration module 4, program control amplification module 5, A/D modular converter 6, Single Chip Microcomputer (SCM) system 7, the sinusoidal wave module 8 that takes place, Synchronous Sampling Pulse module 9, LCD MODULE 10, communication module 11, panel and Keyboard Control module 12, battery and charging module 13 are formed, power source module 1 provides the system testing voltage source signal, by voltage output end mouth U _NhAnd U _NLVoltage signal is delivered to a plurality of pincerlike voltage transformer (VT) be called for short PT or a banded voltage transformer (VT) 14; The sinusoidal wave module 8 that takes place connects power source module 1 input, and battery and charging module 13 connect power source module 1 feeder ear, the input end of the output termination Synchronous Sampling Pulse module (9) of power source module 1, and an input end of multi-way switch module (2); A plurality of split core type current transformers are called for short CT or a banded current transformer 15 passes through electric current port I _NhAnd I _NlCurrent signal is sent into I/V modular converter 3, and the output of I/V modular converter 3 connects another input end of multi-way switch module 2; The output of multi-way switch module 2 connects filtration module 4 input ends, filtration module 4 outputs connect the input end of program control amplification module 5, the output of program control amplification module (5) connects A/D modular converter (6) one input ends, and the output of Synchronous Sampling Pulse module 9 connects A/D modular converter 6 another input ends; News module 11, Single Chip Microcomputer (SCM) system 7, panel and Keyboard Control module 12 are connected in the output of A/D modular converter 6; Single Chip Microcomputer (SCM) system 7 connects by control bus and address/data bus and Synchronous Sampling Pulse module 9 LCD MODULE 10, communication module 11, panel and Keyboard Control module 12, battery and charging module 13.

In the above-mentioned pole tower ground resistance tacheometer 16, power source adopts sinusoidal waveform generation module 8 to generate the sine wave of corresponding frequencies and amplitude, provides the measurement power supply after amplifying through power source module 1 then, and the supply voltage amplitude is 0.5V～5V, power is 1～5W, and survey frequency and amplitude are all adjustable.Built-in rechargeable battery and charging module 13.

Figure 10 is the circuit block diagram that connects filtration module 4, and filtration module 4 is composed in series by 50Hz quadravalence analogue notch 17 and bandpass filter 18.

Figure 11 exempts to separate line pole tower ground resistance rapid measurement device field wiring figure.In the concrete measuring process, at first determine the radical of tested tower grounding downlead, check whether down conductor has tangible disconnection and depredation, confirm whether tested head of mast has lightning conducter and whether be that metal directly is connected with the way of contact of shaft tower.If tested shaft tower has two down conductors, be measured as example to adopt pincerlike PT, CT, clamp two downleads simultaneously with two pincerlike PT and CT respectively, with the voltage port U on two pincerlike PT difference extension bar tower stake resistance tacheometers 16 _1h(passage 1 height), U _1l(passage 1 is low) and U _2h, U _2l, the electrical lead of two pincerlike CT is connected to the current input terminal mouth I of corresponding unanimity respectively _1h, I _1lAnd I _2h, I _2lNotice that the lead sequence number must not make a mistake, and contact is good, confirms to carry out next step after errorless.Turn on the power switch, whether System self-test shows the current electric quantity abundance; By keyboard input average stake resistance of test line shaft tower and lightning conducter electric parameter.Relative parameters setting is finished and can be prepared to begin to measure.

Claims (4)

1. pole tower earthing resistance quick testing method without unfastening wire, adopt the split-core type meter method, by pincerlike voltage transformer (VT), split core type current transformer, measure the shaft tower down conductor, measured voltage, current signal is through Filtering Processing and data analysis, obtain the real part and the imaginary part of the fundametal compoment of current signal and voltage signal, adopt the specific pressure drop computing method to obtain the stake resistance of tested shaft tower, considered the tower grounding resistance in the computing method, it is characterized in that: adopt and exempt to separate line pole tower ground resistance rapid measurement device, use pincerlike voltage transformer (VT) (be called for short pincerlike PT) identical and split core type current transformer (being called for short pincerlike CT) with tower grounding downlead radical, do not understand the tower down conductor of starting, with pincerlike PT, CT clamps all down conductors respectively; Or, use band shape voltage transformer (VT) (being called for short band shape PT) and band shape current transformer (being called for short band shape CT), do not understand the tower down conductor of starting, will be with shape PT, CT to surround whole iron tower; But the function of measuring voltage of providing and measuring voltage is provided pincerlike or band shape PT, pincerlike or band shape CT has the function of measuring electric current, sample respectively for measuring voltage U and electric current I signal, and simulate trap and bandpass filtering, remove power frequency and high-frequency interferencing signal, only allow measuring-signal to pass through, by the Frequency Synchronization of measurement mechanism to voltage and current signals sampling and power source, electric current, voltage signal done the spectrum analysis of widening window, fundametal compoment is wherein separated, further to remove interference components;

The specific pressure drop computing method that adopt are to establish R _gBe a certain pole tower ground resistance value, each down conductor has the connection resistance R ₁, R ₂... R _n,, introduce measuring error and be made as Z for having only a down conductor or using the situation of being with shape PT and CT _E=R _E+ jX _E, the stake resistance measured value is R ' _g=R ₁+ R _g+ Z _E, stake resistance calculates and adopts following formula:

$R_g^{\′}=\mathrm{Re}({\stackrel{\·}{U}}_1/{\stackrel{\·}{I}}_1)$

Wherein,

Be down conductor test voltage value,

Be the current value in down conductor loop, R ' _gFor containing the grounding resistance measurement value of error, its error is by R ₁And Z _ETwo parts are formed, R _eExpression is got real part to plural number, and this moment is approximate thinks R ' _gBe R _gFor situation, introduce measuring error and be made as Z with two or two above down conductors _E=R _E+ jX _E, the stake resistance measured value is R ' _g=R _g+ Z _E, its error only contains Z _EPart connects resistance R ₁, R ₂..., R _nAccurately solve from following equation, stake resistance calculates and adopts following equation:

Wherein

Be each down conductor test voltage value,

Be the current value by each down conductor loop, above-mentioned matrix does not have unique solution, need carry out the second time and measure, only to R ₁Power supply is provided, obtains following additional equation:

${\stackrel{\·}{U}}_1^{\′}-{\stackrel{\·}{I}}_2^{\′}{R}_1=({\stackrel{\·}{I}}_1^{\′}+{\stackrel{\·}{I}}_2^{\′}+\·\·\·+{\stackrel{\·}{I}}_n^{\′}){R_g}^{\′}$

Get by above-mentioned two equations:

For obtaining above-mentioned equation unique solution,, must satisfy following formula according to the linear algebra theory:

$\frac{{\stackrel{\·}{I}}_1}{{\stackrel{\·}{I}}_1^{\′}}\≠\frac{{\stackrel{\·}{I}}_1+{\stackrel{\·}{I}}_2+\·\·\·{\stackrel{\·}{I}}_n}{{\stackrel{\·}{I}}_1^{\′}+{\stackrel{\·}{I}}_2^{\′}+\·\·\·{\stackrel{\·}{I}}_n^{\′}}$

For guaranteeing the following formula establishment, judge earlier whether the data that collect satisfy following formula, if be false, then will

The value change, and measure once more, till following formula was set up, solving an equation then obtained R ' _gThe grounding resistance measurement value R ' that obtains under above-mentioned two kinds of situations _gAll contain error Z _ESo, need be revised, mainly be pure resistive characteristics at the pole tower ground resistance value, only need consider during correction pole tower ground resistance R ' _gReal part correction get final product and Z _EReal part be R _E, correction formula is as follows:

R _E＝-6+0.95lnf+2.3R _d+0.105(lnR _gv) ²+1.75lnR _gv

Wherein f is for measuring supply frequency, R _GvBe the average stake resistance of test line shaft tower, R _dBe the resistance value of every span lightning conducter, obtain revised grounding resistance thus and be:

R _g＝R _e(R _g’)-R _E。

2. exempt to separate line pole tower ground resistance rapid measurement device for one kind, it is characterized in that: be called for short PT (14) by a plurality of pincerlike voltage transformer (VT) or a banded voltage transformer (VT), a plurality of split core type current transformers or a banded current transformer are called for short CT (15) and pole tower ground resistance tacheometer (16) composition, pole tower ground resistance tacheometer (16) is by power source module (1), multi-way switch module (2), I/V modular converter (3), filtration module (4), program control amplification module (5), A/D modular converter (6), Single Chip Microcomputer (SCM) system (7), the sinusoidal wave module (8) that takes place, Synchronous Sampling Pulse module (9), LCD MODULE (10), communication module (11), panel and Keyboard Control module (12), battery and charging module (13) are formed, power source module (1) provides the system testing voltage signal, by voltage output end mouth U _NhAnd U _NLVoltage signal is delivered to a plurality of pincerlike voltage transformer (VT) be called for short a PT or a banded voltage transformer (VT) (14); The sinusoidal wave module (8) that takes place connects power source module (1) input, battery and charging module (13) connect power source module (1) feeder ear, the input end of the output termination Synchronous Sampling Pulse module (9) of power source module (1), and an input end of multi-way switch module (2); A plurality of split core type current transformers are called for short CT or a banded current transformer (15) passes through electric current port I _NhAnd I _NlCurrent signal is sent into I/V modular converter (3), and the output of I/V modular converter (3) connects another input end of multi-way switch module (2); The output of multi-way switch module (2) connects filtration module (4) input end, filtration module (4) output connects the input end of program control amplification module (5), the output of program control amplification module (5) connects A/D modular converter (6) one input ends, and the output of Synchronous Sampling Pulse module (9) connects another input end of A/D modular converter (6); News module (11), Single Chip Microcomputer (SCM) system (7), panel and Keyboard Control module (12) are connected in the output of A/D modular converter (6); Single Chip Microcomputer (SCM) system (7) connects by control bus and address/data bus and Synchronous Sampling Pulse module (9) LCD MODULE (10), communication module (11), panel and Keyboard Control module (12), battery and charging module (13).

3. a kind of line pole tower ground resistance rapid measurement device of exempting to separate as claimed in claim 2 is characterized in that: the measurement power supply that 0.5V～5V/1W～5W is provided after described sinusoidal waveform generation module (8) output signal is amplified through power source module (1).

4. the described a kind of line pole tower ground resistance rapid measurement device of exempting to separate of claim 3, it is characterized in that: filtration module (4) is composed in series by 50Hz quadravalence analogue notch (17) and fourth-order band-pass wave filter (18).

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