CN101576593B - Array type inferior insulator local electric field detector and inverse diagnosis method - Google Patents

Abstract

The invention relates to an array type inferior insulator local electric field detector and an inverse diagnosis method of inferior insulators, which comprises the steps of: implementing non-contact type online quantitative monitoring on a circuit insulator, diagnosing the existence of the inferior insulator through the reverse diagnosis method, really reflecting the insulation safety situation of the circuit insulator, building an insulation safety prewarning information system and implementing effective pre-control management on high-tension transmission lines. The array type inferior insulator local electric field detector consists of a field detector and a data processing center; the method is based on 'electric field method' measuring, which applies the basic principle of the charge simulation method to build a corresponding geometric and mathematical equivalent model. The method obtains the actual voltage distribution of an insulator string by working out the solution of an insulator electric field inverse problem, and compares the actual voltage distribution of the insulator string with the international given voltage distribution to judge the existence and position of the interior insulator in the insulator string.

Description

Array type inferior insulator local electric field detector and inverse diagnosis method

Technical field

The present invention relates to the inferior insulator local electric field detection range, the inverse diagnosis method of particularly a kind of array type inferior insulator local electric field detector and inferior insulator.

Background technology

Detection and insulator state on-line monitoring in order to realize inferior insulator have adopted many methods both at home and abroad.Though the method for monitoring of being adopted at present and detection insulator all has advantage separately; But also come with some shortcomings,, working environment undesirable (much need step on tower) big like on-line monitoring, testing intensity for a long time, influenced by weather condition bigger etc.The method of detection inferior insulator commonly used has at present:

1) determination of insulation resistance method.Utilize the insulation resistance of inferior insulator to reduce, share voltage and reduce, belong to contact type measurement.Air humidity when requiring to measure can not be too big, otherwise be prone to produce erroneous judgement.In addition, should not detect in a large number.

2) spread voltage determination method.Belong to contact type measurement, need under good weather environment, measure.

3) electric field measurement method.Measure the longitudinal electric field distribution situation of insulator surface, detect inferior insulator.Used instrument is comparatively simple, and very low to the requirement of external environments such as weather, measurement point is more.

4) infrared imaging method.Detect shelf depreciation, leakage current etc. and cause that the insulator local temperature raises, but ground detection, but instrument is complicated and be subject to extraneous climatic influences, need carry out at dark a little weather.

5) sound and ultrasonic method.Detect the sound wave that the insulator shelf depreciation is sent, sensitivity is lower than the infrared imaging method, belongs to non-contact measurement.But under the powerful at the scene high voltage magnetic field, distinguish local deterioration discharge signal, acquire a certain degree of difficulty.

6) ultrahigh frequency detection method.Utilize ultra-high frequency antenna to catch the local discharge signal of insulator, carry out spectrum analysis then.Belong to contactless measuring method, be fit to detect shelf depreciation.

7) pulse current method: measure the leakage current of insulator chain, need directly to contact, and receive the influence of high frequency interference easily with insulator chain.

To the detection present situation of present insulator, new insulator detection method, the pick-up unit of development of new are all being studied by the electric power research institution of countries in the world man, and have dropped into a large amount of funds and manpower, and purpose is to improve the reliability of transmission of electricity.How tame electric companies such as Handan, Cangzhou, Baoding, Beijing Power Supply Corp., Datong District's UHV (ultra-high voltage), Beijing UHV (ultra-high voltage), Huhehaote, Datong District, Taiyuan use " electric field method " to detect operating insulator.Application result shows: electric field method can detect the decline of hidden inherent vice and external insulation level, can judge the order of severity that dielectric level descends, and is convenient to carry out the repair based on condition of component of insulator.But the weak point of present electric field method is that when electric pressure raises, the number of the insulator sheet of each string will increase, and the workload of measurement is bigger.Belong to contact type measurement, the security of operation is not high.Simultaneously, this method can not be done detection by quantitative, no datat can supply to analyze, and the preventive management of development of incompatible modern high-voltage fence and science needs, and can't satisfy the requirement of setting up ultra-high-tension power transmission line insulation safety precaution information system.Therefore, a kind of method of desirable detection insulator just seems particularly important with the device of monitoring insulator.

Summary of the invention

The purpose of this invention is to provide a kind of array type inferior insulator local electric field detector, simultaneously, the present invention also provides a kind of method of reverse diagnosis inferior insulator.Line insulator is carried out the Non-contact and On-line Quantitative Monitoring; Existence through inverse diagnosis method diagnosis inferior insulator; Reflect the insulation safety situation of line insulator truly, set up the insulation safety precaution information system, ultra-high-tension power transmission line is carried out effective prevention and control management.

The present invention mainly comprises following content:

1, a kind of array type inferior insulator local electric field detector is made up of on-site detecting device and data processing centre (DPC); Wherein

1), on-site detecting device is made up of electric-field sensor array, high speed data acquisition system, central information processor, GSM data communication module, solar cell and electric power management circuit;

A), the electric-field sensor array is used for the insulator chain internal field signal of collection in worksite work, is fixed on by at least three electric-field sensors on three links of sounding rod to constitute, its output terminal of sensor is connected with the input end of high speed data acquisition system;

B), high speed data acquisition system is used for the electric field intensity analog signal conversion that collects is become digital signal, its output terminal is connected with the input end of central information processor;

C), the central information processor receiving digital signals, and store, its output terminal is connected with the input end of GSM data communication module;

D), the GSM data communication module upload the data to the GPRS communication network, and receives the information that data processing centre (DPC) sends;

E), solar cell is that field device provides power supply, produces the 12V supply voltage, its output terminal is connected with the input end of electric power management circuit;

F), electric power management circuit converts the supply voltage of solar cell the supply voltage of 3.3V to, its output terminal is connected with electric-field sensor array, high speed data acquisition system, central information processor and the power end of GSM data communication module respectively;

2), data processing centre (DPC) is by the gsm communication module, data processing software and PC constitute;

A), the gsm communication module receives the data that field device transmits through GPRS, and the information of data processing software generation is sent in the GPRS network;

B), the electric field information sent of the automatic processing and detecting extension set of data processing software and make corresponding processing, at first according to charge simulation method and least square method ultimate principle, calculate the approximate solution Q of a plurality of electric charges by formula ^*The virtual voltage that is calculated on the insulator sheet of measurement point corresponding position by formula again distributes, and draws out corresponding distribution curve; The voltage that the virtual voltage distribution curve of insulator chain and GB is given distributes and carries out difference mutually relatively: there is probability maximum inferior in the insulator sheet that the difference maximum is corresponding, thereby judges having or not and the position of inferior insulator sheet in the insulator chain; If there is fault, to numbering, position that the field staff sends the abnormal insulator of operation, notify its inspection through GPRS network.

Whether 2, the above-mentioned array type inferior insulator local electric field detector of a kind of employing, reverse diagnosis insulator deterioration and the method for confirming its concrete site numbering: method may further comprise the steps:

1), sets up GB under the different electric pressures given insulator site numbering and corresponding voltage value, and insulator chain voltage distribution curve database;

2), set up on-the-spot electric-field sensor and measure array, the quantity of the electric-field sensor that adopts in the measurement array of each insulator chain is less than the number of insulator, but is no less than 3, carries out image data;

3), will obtain insulator chain internal field signal, be sent to host computer through GPRS network;

4), according to charge simulation method and least square method ultimate principle, calculate the approximate solution of a plurality of electric charges by formula (3);

5), the virtual voltage that calculated on the insulator sheet of measurement point corresponding position by formula (1) again distributes, and draws out corresponding distribution curve;

6), voltage that the virtual voltage distribution curve and the GB of insulator chain is given distributes and carry out difference mutually relatively: there is probability maximum inferior in the insulator sheet that the difference maximum is corresponding, thereby judges having or not and the position of inferior insulator sheet in the insulator chain; If there is fault, send indication to the field staff through GPRS network.

Said method is based upon on " electric field method " based measurement; Measure the electric field intensity of the finite point near the certain distance scope of insulator chain; According to size, shape and the position etc. of insulator to be detected, the ultimate principle of application simulation charge method is set up corresponding how much and mathematics equivalent model.Through finding the solution separating of insulator electric field inverse problem, obtain the virtual voltage distribution of insulator chain, the voltage that virtual voltage distributes and GB the is given distribution of insulator chain is compared, the inferior insulator sheet has or not and the position in the judgement insulator chain.The theoretical foundation of said method comprises:

1), insulator equivalent model

The accuracy that the direct decision of model is found the solution; Utilize the rotational symmetry characteristic of insulator structure; Adopt its surperficial bound charge of looped cord charge simulation equivalence according to charge simulation method ultimate principle, charge simulation must satisfy the voltage of insulator surface and electrode surface and the boundary condition of electric field.

2), the foundation of system's inverse problem with find the solution

Set up the inverse problem equation according to equivalent model.Insulator electric field inverse problem is to calculate the Potential distribution on insulator chain surface according to the electric field intensity of limited measurement point; In order to reduce surveying work; The number of measurement point should be lacked as much as possible; But when the value of measurement point too hour, the precision of the approximate solution of calculating is too low, separating of this moment do not have practical significance.Therefore seeking the number of the measurement point of a minimum, make that finding the solution the separating of inverse problem equation that obtains has practical meaning, is one of key of this method.Simultaneously, inverse problem is a underdetermined equation, and key is to seek fast, accurately to find the solution the feasible method of inverse problem approximate solution.Have only and obtain the higher approximate solution of precision fast and in the detection of engineering, just be of practical significance.

3), insulator judgement inferior

If have the deterioration insulator in the insulator chain; Under the extreme case, being equivalent to this sheet insulator dielectric resistance is zero, and the voltage landing at deterioration insulator place is near zero; Share the voltage of bearing by the deterioration insulator originally by other insulators, certainly will cause the voltage distribution curve more inhomogeneous.Insulator judgment basis inferior is exactly to compare with the given voltage distribution value of GB according to the virtual voltage distribution value of insulator chain, judge have or not the inferior insulator sheet with and the position.

This method is applicable to:

1) insulator that is used to detect the power circuit of various electric pressures detects, implement to judge have or not the inferior insulator sheet with and the position;

2) the power transmission line running status that is used for various electric pressures detects;

3) to the common ground of the electric field of power equipment, the application of this inverse problem can extend to the detection and the analysis of electric system power frequency electromagnetic field electromagnetic compatibility of other power equipments.

Array type inferior insulator local electric field detector provided by the invention and inverse diagnosis method may be used in the diagnosis of inferior insulator, have realized contactless, charged offline inspection.This device is contactless hot line job, operates safelyr, and the measurement point number that needs is less, and actual surveying work amount is less.Not only timely detection insulator is had or not inferior most importantly, and the state-detection and the safety and stability of other power equipments of electric system all had crucial meaning.

Description of drawings

The structured flowchart of Fig. 1 array type inferior insulator local electric field detector of the present invention;

Fig. 2 on-site detecting device 1 structured flowchart;

The structured flowchart of Fig. 3 data processing centre (DPC) 2;

Fig. 4 electric-field sensor array 11 synoptic diagram;

The distribution schematic diagram of Fig. 5 three-phase insulator strings charge simulation and match point and measurement point;

The distribution schematic diagram of Fig. 6 list insulator chain charge simulation and match point and measurement point;

Fig. 7 insulator is inferior to compare distribution plan with normal voltage;

Fig. 8 is the operational flowchart of the inventive method.

Embodiment

Embodiment 1 array type inferior insulator local electric field detector

Constitute with data processing centre (DPC) 2 by on-site detecting device 1; Wherein

1), on-site detecting device 1 is made up of electric-field sensor array 11, high speed data acquisition system 12, central information processor 13, GSM data communication module 14, solar cell 15 and electric power management circuit 16;

A), electric-field sensor array 11 is used for the insulator chain internal field signal of collection in worksite work, is fixed on by at least three electric-field sensors on three links of sounding rod to constitute, its output terminal of sensor is connected with the input end of high speed data acquisition system 12;

B), high speed data acquisition system 12 is used for the electric field intensity analog signal conversion that collects is become digital signal, its output terminal is connected with the input end of central information processor 13;

C), central information processor 13 receiving digital signals, and store, its output terminal is connected with the input end of GSM data communication module 14;

D), GSM data communication module 14 upload the data to the GPRS communication network, and receives the information that data processing centre (DPC) sends;

E), solar cell 15 is for field device provides power supply, produces the 12V supply voltage, its output terminal is connected with the input end of electric power management circuit 16;

F), electric power management circuit 16 converts the supply voltage of solar cell the supply voltage of 3.3V to, its output terminal is connected with the power end of electric-field sensor array 11, high speed data acquisition system (12), central information processor (13) and GSM data communication module 14 respectively;

2), data processing centre (DPC) 2 is by gsm communication module 21, data processing software 22 constitutes with PC 23;

A), gsm communication module 21 receives the data that field device transmits through GPRS, and the information of data processing software generation is sent in the GPRS network TC35i that adopts Siemens Company to produce;

B), the electric field information sent of data processing software 22 automatic processing and detecting extension sets and make corresponding processing, at first according to charge simulation method and least square method ultimate principle, calculate the approximate solution Q of a plurality of electric charges by formula (3) ^*The virtual voltage that is calculated on the insulator sheet of measurement point corresponding position by formula (1) again distributes, and draws out corresponding distribution curve; The voltage that the virtual voltage distribution curve of insulator chain and GB is given distributes and carries out difference mutually relatively: there is probability maximum inferior in the insulator sheet that the difference maximum is corresponding, thereby judges having or not and the position of inferior insulator sheet in the insulator chain; If there is fault, to numbering, position that the field staff sends the abnormal insulator of operation, notify its inspection through GPRS network.

Among the embodiment, the electric-field sensor array is that RJ-5 electric-field sensor and ground liftable sounding rod constitute by three models, and sensor is fixed on the sounding rod; The analog to digital converter TLV1578IDA that high speed data acquisition system 12 adopts TI company to produce; The digital signal processor TMS320LF2407 that central information processor 13 adopts TI company to produce; The TC35i that GSM data communication module 14 adopts Siemens Company to produce; The solar electric power supply system that solar cell 15 employing Shenzhen A Bolai Science and Technology Ltd.s produce; Electric power management circuit 16 adopts power conversion chip LT1764A-3.3V.

Embodiment 2 adopts the described array type inferior insulator local electric field detector of claims 1, and whether the reverse diagnosis insulator deterioration and the method for confirming its concrete site numbering: method may further comprise the steps:

1), sets up GB under the different electric pressures given insulator site numbering and corresponding voltage value, and insulator chain voltage distribution curve database;

2), set up on-the-spot electric-field sensor and measure array, the quantity of the electric-field sensor that adopts in the measurement array of each insulator chain A is less than the number of insulator, but is no less than 3, carries out image data;

3), will obtain insulator chain internal field signal, be sent to host computer through GPRS network;

4), according to charge simulation method and least square method ultimate principle, calculate the approximate solution Q of a plurality of electric charges by formula (3) ^*

5), the virtual voltage that calculated on the insulator sheet of measurement point corresponding position by formula (1) again distributes, and draws out corresponding distribution curve;

6), voltage that the virtual voltage distribution curve and the GB of insulator chain is given distributes and carry out difference mutually relatively: there is probability maximum inferior in the insulator sheet that the difference maximum is corresponding, thereby judges having or not and the position of inferior insulator sheet in the insulator chain; If there is fault, send indication to the field staff through GPRS network.

If have the deterioration insulator in the insulator chain, the voltage landing at deterioration insulator place has been shared the voltage of being born by the deterioration insulator originally by other insulators, certainly will cause the voltage distribution curve more inhomogeneous.The voltage skewness will cause that the electric field of insulator near zone will change.Electric-field sensor sends note with the electric field value that measures through the GSM data communication and gives Control Room.The monitoring software of Control Room, automatically the anomalous electric field information sent of processing and detecting extension set and make corresponding processing.Monitoring software based on database constitutes has each outdoor insulator information at lane database, as the phone number of insulator infield, numbering, installation early warning system, recently a period of time operation conditions, this circuit patrol and examine responsible official etc.After the monitoring software judgement receives alarming short message, make a series of processing automatically: send sound and light alarm on the computer, remind the monitor staff; Send numbering, the position of the abnormal insulator of operation for the personnel of patrolling and examining, notify its inspection.

Above-mentioned inverse diagnosis method is meant the characterisitic parameter (as: source parameter, structural parameters or medium characterisitic parameter) of known system; Find the solution its field domain (like electromagnetic field, stress field, elastic field, acoustic wavefield or biological field) distribution character, calculate its Electric Field Distribution on every side like the insulator boundary condition.But in actual engineering; Many times the characterisitic parameter of system is unknown, is known that the field domain distribution character of system, in order to grasp the internal state of system; Need calculate its characterisitic parameter according to known system's field domain distribution character, this process is exactly the reverse diagnosis of system.The voltage according to the electric Field Calculation insulator as in this method distributes.

Because the rotational symmetry characteristic of insulator structure is according to its surperficial bound charge of ultimate principle employing looped cord charge simulation equivalence of charge simulation method (CSM).Charge simulation must satisfy the voltage of insulator surface and electrode surface and the boundary condition of electric field, therefore is provided with after the match point of equivalent model, and the augmented matrix equation that can obtain system is:

P*Q＝U (1)

In the formula: [P] is coefficient of potential matrix, and [U] is the current potential matrix, [E _r] be r direction of principal axis component part of electric field matrix in the cylindrical coordinates, [E _z] be z direction of principal axis component part of electric field matrix in the cylindrical coordinates, [f _r] be r direction of principal axis component part of electric field matrix of coefficients in the cylindrical coordinates, [E _z] be z direction of principal axis component part of electric field matrix of coefficients in the circular cylindrical coordinate.

In addition, because insulator surface is a bound charge, also should satisfy

$\underset{i=0}{\overset{n}{\mathrm{\Σ}}}{Q}_i=0---\left(2\right)$

Therefore can calculate the distribution of current potential in the field domain or electric field according to [Q].And finding the solution of [Q] is current potential or the electric field value according to match point; Therefore the direct problem of the current potential of insulator system or electric field is for passing through match point; It is the distribution of current potential and electric field in current potential or the electric Field Calculation field domain of frontier point; And inverse problem is the current potential or the electric field of the Distribution calculation frontier point of current potential through field domain or electric field, and this inverse problem is the boundary condition inverse problem.

The quantity n that keeps charge simulation _cConstant, reduce the number n of measured point _p, make n _p＜n _c, therefore work as n _pThe workload of surveying work is less when very little.Clearly the dimension of inverse problem equation is n at this moment _p, equation is an Indeterminate Equation Group, does not confirm to separate.According to the ultimate principle of least square method, can calculate the approximate solution [Q of inverse problem according to formula (3) ^*].All exist the institute of inferior insulator possible in the insulator chain in order to find out in the method, and we calculate a plurality of approximate solutions of inverse problem according to formula (3) and formula (4).

$\underset{Q}{\min }\left|\right|\sqrt{{\left[E_r\right]}^2+{\left[E_z\right]}^2}-\left[E\right]\left|\right|$

[E _r]＝[f _r][Q ^*]，[E _z]＝[f _z][Q ^*] (3)

In the formula: [E] is the electric field of measurement point;

‖[Q]-[Q] ^*‖ξ(4)

In the formula: ξ is the error permissible value.

In the measurement of reality, n _pThe more little measuring operation of value Vietnamese side just, but work as n _pValue too hour, this moment is too low according to the precision of the approximate solution that formula (3) is calculated, separating of this moment do not have practical significance.Therefore seek the n of a minimum _p, make that finding the solution the separating of inverse problem equation that obtains has practical meaning, be the key of this method.The core of this research is sought the inverse problem approximate solutions of equations exactly.

Inverse problem according to the electric field shown in the formula (3) can be known; Its process for go to know by inference according to " really " that measure " because of "; In the numerical evaluation of reality, such problem often is exactly (ill-posed), ill posed of morbid state, and promptly separating of inverse problem possibly occur 1) nonexistence; 2) uniqueness not; 3) instability.Generally very little disturbance will cause the very big fluctuation of separating, thereby makes the result who infers lose realistic meaning.

The morbid state of inverse problem causes by its " sick condition ", and promptly the small sample perturbations of the measurement data of inverse problem can cause the great variety of separating, and for the degree of " the sick condition " of the problem of portraying, introduces the notion of conditional number.With continuous function f (x) is example, in order to estimate the size of the influence that x produces f (x) at certain slight disturbance h on a bit, at first according to mean value theorem, exists ε ∈ [x, x+h] to satisfy:

f(x+h)-f(x)＝f′(ε)h≈f′(x)h (5)

Consider relative error, then have

$\frac{f(x+h)-f\left(x\right)}{f\left(x\right)}\≈\frac{f^{\′}\left(x\right)h}{f\left(x\right)}=\frac{x{f}^{\′}\left(x\right)}{f\left(x\right)}\·\frac{h}{x}---\left(6\right)$

Formula (6) has been reacted the influence of the relative error of x to the relative error of f (x), and wherein

is just as the conditional number of this problem.

For linear operator equation (being system of linear equations) Ax=y, when A nonsingular, i.e. A ^-1Exist and bounded.If the disturbance Δ x that the last disturbance Δ y of y produces x, i.e. A (x+ Δ x)=y+ Δ y, then Δ x=A ^-1Δ y can get ‖ Δ x ‖≤‖ A by the definition of operator norm ^-1‖ ‖ Δ y ‖ has ‖ y ‖≤‖ A ‖ ‖ x ‖ simultaneously, therefore has

$\frac{\left|\right|\mathrm{\Δx}\left|\right|}{\left|\right|x\left|\right|}\≤\left|\right|A\left|\right|\left|\right|A^{-1}\left|\right|\frac{\left|\right|\mathrm{\Δy}\left|\right|}{\left|\right|y\left|\right|}---\left(7\right)$

Formula (7) is described the inequality relation of understanding that relative error satisfied.Make the conditional number cond (A) of A be: cond (A)=‖ A ‖ ‖ A ^-1‖

$\frac{\left|\right|\mathrm{\Δx}\left|\right|}{\left|\right|x\left|\right|}\≤\mathrm{cond}\left(A\right)\frac{\left|\right|\mathrm{\Δy}\left|\right|}{\left|\right|y\left|\right|}---\left(8\right)$

Then formula (8) is explained, if the conditional number of cond (A) is more little, then ‖ Δ x ‖/‖ x ‖ is more little, and the ill degree of problem Ax=y is low more; Otherwise the conditional number of cond (A) is big more, and then ‖ Δ x ‖/‖ x ‖ is big more, and the ill degree of problem Ax=y is high more, and therefore the ill degree of a problem is relevant with the size of its conditional number.

For finding the solution of linear underdetermined system of equations Ax=y, usually adopt least square method to calculate its optimal approximation and separate, be i.e. minimum norm ‖ Ax-y ‖ ², can know according to the definition of least square method, separate x for the optimal approximation of equation Ax=y ^*In its field of definition, satisfy:

‖Ax ^*-y‖ ²≤‖Ax-y‖ ²， $\∀x\∈X$ (9)

Be x ^*Be separating of following functional extreme value problem:

$\underset{x\∈X}{\min }{\left|\right|\mathrm{Ax}-y\left|\right|}^2---\left(10\right)$

Can prove that this extreme-value problem is of equal value and find the solution equation:

A ^*Ax＝A ^*y (11)

A wherein ^*: the adjoint operator of A.That is to say x ^*Be separating of this equation, defining equation (11) is the normal equation of equation Ax=y.Be pointed out that if equation Ax=y morbid state, then the morbid state of its normal equation (11) is more serious.

Say from the angle of optimum theory, in order to solve the ill-conditioning problem of above-mentioned extreme-value problem, it is increased a penalty term, punish the x that those norms are big, then formula (10) becomes:

$\underset{x\∈X}{\min }({\left|\right|\mathrm{Ax}-y\left|\right|}^2+\mathrm{\α}{\left|\right|x\left|\right|}^2)---\left(12\right)$

Make J _a(x)=‖ Ax-y ‖ ²+ α ‖ x ‖ ², J then _a(x) become the Tikhonov functional, this extreme-value problem separate x _aAlso be the unique solution of its normal equation, promptly

A ^*Ax _a+αx _a＝A ^*y (13)

Formula (13) can be written as:

x _a＝(A ^*A+αI) ^-1A ^*y (14)

Order

R _α＝(A ^*A+αI) ^-1A ^* (15)

If the Gee system of A is (μ _l, x _l, y _l), then

$R_{\mathrm{\&alpha;}}y={(A^{*}A+\mathrm{\&alpha;I})}^{-1}{A}^{*}y={(A^{*}A+\mathrm{\&alpha;I})}^{-1}{A}^{*}(\underset{i=0}{\overset{\&infin;}{\mathrm{\&Sigma;}}}<y,y_i>y_i)$

$={(A^{*}A+\mathrm{\&alpha;I})}^{-1}{A}^{*}(\underset{i=0}{\overset{\&infin;}{\mathrm{\&Sigma;}}}<y,y_i>{\mathrm{\&mu;}}_i{y}_i)---\left(16\right)$

Again $(A^{*}A+\mathrm{\&alpha;\; I})x_i=(\mathrm{\&alpha;}+{\mathrm{\&mu;}}_i^2)x_i,$ Therefore ${(A^{*}A+\mathrm{\&alpha;\; I})}^{-1}{x}_i=x_i/(\mathrm{\&alpha;}+{\mathrm{\&mu;}}_i^2),$ Then

$R_{\mathrm{\&alpha;}}y=\underset{i=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}\frac{{\mathrm{\&mu;}}_i<y,y_i>x_i}{\mathrm{\&alpha;}+{\mathrm{\&mu;}}_i^2}=\underset{i=1}{\overset{\&infin;}{\mathrm{\&Sigma;}}}\frac{q(\mathrm{\&alpha;},{\mathrm{\&mu;}}_i)}{{\mathrm{\&mu;}}_i}<y,y_i>x_i---\left(17\right)$

In the formula: q (α, β)=β ²/ (alpha+beta ²), be the canonical wave filter.

The morbid state of inverse problem mainly is that difference is separated through after the positive operator mapping because " filtration " effect of positive operator causes, and its difference has just been filtered.In these external actual conditions, data can only and be obtained after the noise pollution through observation discrete, limited number of time, and this has more aggravated the ill degree of problem.For the morbid state of dealing with problems, must increase prior imformation physically, and combine the regularization technology, prior imformation is coupled in the inverse problem solution procedure, inverse operator is replaced (being similar to) by the better operator of performance, and the information that some are lost is able to recover.

3 one actual measurement effects of embodiment

Table 1 is 110kv insulator normal voltage distribution (kV)

Measurement point Electric Field Distribution (kV/m) when table 2 is 110kv insulator poor quality

Table 3 is the voltage distribution (kV) that 110kv electric field inverse problem is handled through regularization

Through on-the-spot electric-field sensor array, image data such as table 2 according to charge simulation method and least square method ultimate principle, shown in (1), (3), are tried to achieve virtual voltage grade such as table 3 on the insulator chain; Thereby the virtual voltage grade and the table 1 insulator normal voltage grade of trying to achieve are arranged, draw out virtual voltage and the normal voltage curve distribution is as shown in Figure 6.

Diagnosis:

1, if corresponding corresponding numbering place virtual voltage distribution curve compare with the given normal voltage distribution curve of GB, for reduce change difference more general goal possibly exist poor quality property bigger, thereby judge having or not and the position of insulator chain poor quality.

Or 2, reductions if the curve of measurement point is undergone mutation, then can judge this sheet insulator and have poor quality; If be separated by a slice insulator between measurement point, the curve reduction of undergoing mutation, then can judge this sheet insulator is inferior insulator; If be separated by two insulators between measurement point, curve reductions of undergoing mutation then can be through comparing with the given voltage respective level of GB, reduce the variation difference more general goal possibly exist poor quality property bigger, thereby judge, and by that analogy.

Claims (2)

1. an array type inferior insulator local electric field detector is characterized in that: be made up of on-site detecting device (1) and data processing centre (DPC) (2); Wherein

1), on-site detecting device (1) is made up of electric-field sensor array (11), high speed data acquisition system (12), central information processor (13), GSM data communication module (14), solar cell (15) and electric power management circuit (16);

A), electric-field sensor array (11) is used for the insulator chain internal field signal of collection in worksite work; Be fixed on by at least three electric-field sensors on three links of sounding rod and constitute, its output terminal of sensor is connected with the input end of high speed data acquisition system (12);

B), high speed data acquisition system (12) is used for the electric field intensity analog signal conversion that collects is become digital signal, its output terminal is connected with the input end of central information processor (13);

C), central information processor (13) receiving digital signals, and store, its output terminal is connected with the input end of GSM data communication module (14);

D), GSM data communication module (14) upload the data to the GPRS communication network, and receives the information that data processing centre (DPC) sends;

E), solar cell (15) is for on-site detecting device provides power supply, produces the 12V supply voltage, its output terminal is connected with the input end of electric power management circuit (16);

F), electric power management circuit (16) converts the supply voltage of solar cell the supply voltage of 3.3V to, its output terminal is connected with electric-field sensor array (11), high speed data acquisition system (12), central information processor (13) and the power end of GSM data communication module (14) respectively;

2), data processing centre (DPC) (2) is by gsm communication module (21), data processing software (22) and PC (23) constitute;

A), gsm communication module (21) receives the data that on-site detecting device transmits through GPRS, and the information of data processing software generation is sent in the GPRS network;

B), the automatic electric field information sent of processing and detecting extension set and make corresponding processing of data processing software (22), at first according to charge simulation method and least square method ultimate principle, by formula (3):

$\underset{Q}{\min }\left|\right|\sqrt{{\left[E_r\right]}^2+{\left[E_z\right]}^2}-\left[E\right]\left|\right|$

[E _r]＝[f _r][Q ^*]，[E _z]＝[f _z][Q ^*] (3)

Calculate the approximate solution Q of a plurality of electric charges ^*

The virtual voltage that is calculated on the insulator sheet of measurement point corresponding position by formula (1) again distributes, and draws out corresponding distribution curve; The voltage that the virtual voltage distribution curve of insulator chain and GB is given distributes and carries out difference mutually relatively: there is probability maximum inferior in the insulator sheet that the difference maximum is corresponding, thereby judges having or not and the position of inferior insulator sheet in the insulator chain; If there is fault, to numbering, position that the field staff sends the abnormal insulator of operation, notify its inspection through GPRS network:

P*Q＝U (1)

In the formula: [P] is coefficient of potential matrix, and [U] is the current potential matrix, and [E] is the electric field of measurement point, [E _r] be r direction of principal axis component part of electric field matrix in the cylindrical coordinates, [E _z] be z direction of principal axis component part of electric field matrix in the cylindrical coordinates, [f _r] be r direction of principal axis component part of electric field matrix of coefficients in the cylindrical coordinates, [f _z] be z direction of principal axis component part of electric field matrix of coefficients in the cylindrical coordinates.

2. one kind is adopted the described array type inferior insulator local electric field detector of claim 1, and whether the reverse diagnosis insulator deterioration and the method for confirming its concrete site numbering: method may further comprise the steps:

1), sets up GB under the different electric pressures given insulator site numbering and corresponding voltage value, and insulator chain voltage distribution curve database;

2), set up on-the-spot electric-field sensor and measure array, the quantity of the electric-field sensor that adopts in the measurement array of each insulator chain (A) is less than the number of insulator, but is no less than 3, carries out image data;

3), will obtain insulator chain internal field signal, be sent to host computer through GPRS network;

4), according to charge simulation method and least square method ultimate principle, calculate the approximate solution of a plurality of electric charges by formula (3);

5), the virtual voltage that calculated on the insulator sheet of measurement point corresponding position by formula (1) again distributes, and draws out corresponding distribution curve;

6), voltage that the virtual voltage distribution curve and the GB of insulator chain is given distributes and carry out difference mutually relatively: there is probability maximum inferior in the insulator sheet that the difference maximum is corresponding, thereby judges having or not and the position of inferior insulator sheet in the insulator chain; If there is fault, send indication to the field staff through GPRS network.

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