CN104360240A - Quick detecting device and method for defective equipment of transformer substation - Google Patents

Abstract

The invention discloses a quick detecting device and method for defective electrical equipment of a transformer substation. The quick detecting device is composed of a plurality of electric wave sensors, an ultra high-speed data sampling unit and a data processing unit. The quick detecting method includes that the electric wave sensors receive electric signals generated from insulating defective discharging of the defective electrical equipment of the transformer substation to be detected; after amplified and filtered by front wide-and amplifiers, the electric signals are synchronously collected by the ultra high-speed data sampling unit and then sent to the data processing unit for data processing to four-way signals; the position of a discharging source and warning information are displayed on a display screen. By the use of the quick detecting device and method, detection and planar location of the discharging source of detective equipment in the transformer substation are facilitated, so that cost for discharge detection of the defective equipment of the transformer substation is lowered, defects are found in advance when the transformer substation equipment is under detection, power failures rarely occur, and intelligent degree of the transformer substation is improved. The quick detecting device and method has the advantages that the discharge detection of the whole transformer substation to be detected is achieved in the quick-positioning, low-cost and high-efficiency manner.

Description

Transformer station's defect equipment device for fast detecting and detection method

Technical field

The present invention relates to electric system high voltage and insulation technology, particularly relate to a kind of transformer station defect power equipment device for fast detecting and detection method thereof.

Background technology

Insulation fault is that power equipment is in operation one of topmost possible breakdown, before power equipment generation insulation fault, generally all can have a discharge process developed gradually, finally cause insulation breakdown.If can carry out electric discharge detection and diagnosis to operational outfit in this process, Timeliness coverage discharge signal, processes defect in advance, just effectively can avoid the generation of Fault of Insulating Breakdown.Also contribute to formulating overhaul plan scheme more targetedly to the location of discharge position, reduce power off time, improve overhaul efficiency.

Defect electric discharge detects by the multiple method such as ultrasound wave, electric parameter constant and superfrequency electromagnetic wave, and these methods all can be used to location.Superfrequency Electromagnetic Wave Method is a kind of new method of discharge examination, and the super high band signal in the electromagnetic wave of radiation when the method is by occurring to discharge in superfrequency omnidirectional sensor reception power equipment detects electric discharge.The advantage of superfrequency Electromagnetic Wave Detection is: detect frequency range higher, effectively can avoid the multiple electrical Interference such as corona, switching manipulation in conventional discharge measurement; Measurement bandwidth is wide, so its detection sensitivity is very high, and the aerial velocity of propagation of electromagnetic wave is similar to the light velocity, can be used for calculating the planimetric position of discharge source in transformer station, thus determines the equipment of possibility existing defects.

The method that the existing insulation defect to power equipment is monitored and located both at home and abroad is substantially all detect for the electric discharge of single substation equipment (GIS, transformer, capacitive apparatus etc.), and positions according to the acoustical signal collected and electric signal.There is following defect in this monitoring method:

1) any high voltage electric power equip ment in transformer station all may produce discharge fault, want to implement monitoring to an electrical equipment at full station, just need all to install discharge monitoring device on each device, this needs the time of at substantial, financial resources carry out equipment purchase and installation;

2) many covers dissimilar instrument need be carried during test, operation inconvenience;

3) maintenance and management of numerous monitoring device needs time and the manpower of at substantial.

Therefore, current this monitoring form is difficult to the requirement adapting to intelligent substation telemanagement from now on and few man on duty.

Summary of the invention

In order to solve the problems of the technologies described above, the invention provides a kind of transformer station defect power equipment device for fast detecting.

Transformer station provided by the invention defect power equipment device for fast detecting, be made up of superfrequency omnidirectional sensor reception amplification module, Ultrahigh speed data sampling unit and data processing unit and analytic unit, described superfrequency omnidirectional sensor receives the conglomerate that amplification module is four omnidirectional wideband antennas and wideband pre-amplifier thereof, described superfrequency omnidirectional sensor receives converting station electric power equipment deficiency to be measured and to discharge the electromagnetic wave produced, through described wideband pre-amplifier amplify and after filtering process by described ultra-high-speed data acquisition units synchronization collection;

Described data processing unit carries out data processing unit to four road signals, and emphasis is the time delay of calculating four road signal, thus calculates the planimetric position of discharge source in transformer station.

Preferably, the bandwidth of described wideband pre-amplifier is 1GHz, and gain is 40dB.

Preferably, described Ultrahigh speed data sampling unit is the data collecting card of >3Gsps.

Preferably, described data processing unit is industrial control computer.

Invention also provides and a kind ofly utilize arbitrary described transformer station's defect power equipment device for fast detecting in technique scheme to carry out the method for discharge source detection, comprise step one multichannel electric wave signal synchronous collection, step 2 adopts the time delay of bi-spectrum estimation algorithm determination two-way electric wave signal and step 3 to utilize time-delay calculation to discharge the planimetric position of source point;

Step one multichannel electric wave signal synchronous collection

By described transformer station defect power equipment device for fast detecting after a certain position of transformer station to be measured is placed, after described pick-up unit starts, described hyperchannel superfrequency omnidirectional sensor receives the electromagnetic wave signal that transformer station's defect power equipment produces because of electric discharge, amplify through described wideband pre-amplifier and carry out synchronous acquisition by described ultra-high-speed data acquisition unit after filtering process, sending described data processing unit to carry out data processing unit to multiple signals;

Step 2 adopts the time delay of bi-spectrum estimation algorithm determination two-way electric wave signal

The two paths of signals simultaneously collected by the digital acquisition system of signal is respectively discrete series { x1 (n) } and { x2 (n) }, in conjunction with Higher Order Cumulants theory, utilize the computer numerical implementation method of parameter two spectrum Time Delay Estimation Algorithms, calculate sub-step as follows

Sub-step 1: same to conventional Calculation Method, is divided into K section by the signal data sample observed, every section comprises M observation sample, is denoted as respectively wherein k=1,2 ..., k, i=1,2, can coincidence be had between adjacent two segment datas;

Sub-step 2: calculate every segment signal from Third-order cumulants and mutual Third-order cumulants:

${\hat{c}}_{x_1{x}_1{x}_1}^{\left(k\right)}(\mathrm{\τ},\mathrm{\ρ})=\frac{1}{M}\underset{n=S_1}{\overset{S_2}{\mathrm{\Σ}}}{x}_1^{\left(k\right)}\left(n\right)x_1^{\left(k\right)}(n+\mathrm{\τ})x_1^{\left(k\right)*}(n+\mathrm{\ρ})$

${\hat{c}}_{x_1{x}_2{x}_1}^{\left(k\right)}(\mathrm{\τ},\mathrm{\ρ})=\frac{1}{M}\underset{n=S_1}{\overset{S_2}{\mathrm{\Σ}}}{x}_1^{\left(k\right)}\left(n\right)x_2^{\left(k\right)}(n+\mathrm{\τ})x_1^{\left(k\right)*}(n+\mathrm{\ρ})---\left(1\right)$

Wherein, S1 and S2 respectively value be:

S ₁＝max(0,-τ,-ρ)

S ₂＝min(M-1,M-1-τ,M-1-ρ)

Sub-step 3: calculate the mean value of each segment signal from Third-order cumulants and mutual Third-order cumulants, the Third-order cumulants as whole segment signal is estimated:

${\hat{C}}_{x_1{x}_1{x}_1}(\mathrm{\τ},\mathrm{\ρ})=\frac{1}{K}\underset{k=1}{\overset{K}{\mathrm{\Σ}}}{\hat{c}}_{x_1{x}_1{x}_1}^{\left(k\right)}(\mathrm{\τ},\mathrm{\ρ})$

${\hat{C}}_{x_1{x}_2{x}_1}(\mathrm{\τ},\mathrm{\ρ})=\frac{1}{K}\underset{k=1}{\overset{K}{\mathrm{\Σ}}}{\hat{c}}_{x_1{x}_2{x}_1}^{\left(k\right)}(\mathrm{\τ},\mathrm{\ρ})---\left(3\right)$

Sub-step 4: utilize with write out matrix and vector and list system of equations:

${\hat{C}}_{x_1{x}_1{x}_1}={\hat{C}}_{x_1{x}_2{x}_1}A---\left(4\right)$

Wherein

$C_{x_1{x}_2{x}_1}={[c_{x_1{x}_2{x}_1}(-p,0),...,c_{x_1{x}_2{x}_1}(p,0),c_{x_1{x}_2{x}_1}(-p,1),...,c_{x_1{x}_2{x}_1}(p,1),c_{x_1{x}_2{x}_1}(-p,-1),...,c_{x_1{x}_2{x}_1}(p,-1)]}^T$

A＝[a _-p,a _-p+1,…,0,…,a _p-1,a _p] ^T

Sub-step 5: utilize least square method to solve above-mentioned system of equations, estimate vector

$\hat{A}={\left({\hat{C}}_{x_1{x}_1{x}_1}^T{\hat{C}}_{x_1{x}_1{x}_1}\right)}^{-1}{\hat{C}}_{x_1{x}_1{x}_1}^T{\hat{C}}_{x_1{x}_2{x}_1}---\left(5\right)$

Wherein to make get the index value d of maximal value, as the estimation of two paths of signals time delay

Step 3 utilizes the planimetric position of time-delay calculation electric discharge source point

Native system considers that power equipment is all floor plan in transformer station, determine the power equipment of possibility existing defects, only need calculate the planimetric position of discharge source in transformer station, sensor array adopts planar rectangular arrangement mode for this reason, supposes that the position coordinates of four sensors in plane coordinate system is respectively (x ₁, y ₁), (x ₂, y ₂), (x ₃, y ₃) and (x ₄, y ₄), discharge source position is (x, y), and the distance between discharge source and four sensors is respectively d ₁, d ₂, d ₃and d ₄, namely

$d_i=\sqrt{{(x-x_i)}^2+{(y-y_i)}^2},i=\mathrm{1,2,3,4}---\left(6\right)$

According to plane analytic geometry knowledge, the range difference (d between discharge source to every two sensors _i-d _j) uniquely can determine that a list props up hyperbolic curve, therefore, take antenna array center as planimetric rectangular coordinates initial point, point of discharge place quadrant can be determined by the mistiming, utilize the list of equidirectional to prop up Hyperbolic Equation simultaneous and can obtain following Nonlinear System of Equations:

$\left\{\begin{array}{c}\frac{x^2}{a_{12}^2}-\frac{y^2}{b_{12}^2}=1\\ \frac{x^2}{a_{43}^2}-\frac{y^2}{b_{43}^2}=1\end{array}\right.---\left(7\right)$

$\left\{\begin{array}{c}\frac{x^2}{a_{14}^2}-\frac{y^2}{b_{14}^2}=1\\ \frac{x^2}{a_{23}^2}-\frac{y^2}{b_{23}^2}=1\end{array}\right.---\left(8\right)$

A in formula _ij=(d _i-d _j)/2---hyp semi-major axis is long;

---hyp semi-minor axis long square;

C _ij---hyperbolic curve focal length, can obtain according to the size of aerial array;

Suppose that the waveform initial time of four road discharge signals is respectively dt ₁, dt ₂, dt ₃and dt ₄, discharge signal is transmitted to the mistiming Δ T of different antennae ₁₂, Δ T ₄₃, Δ T ₁₄, Δ T ₂₃can be expressed as

$\left\{\begin{array}{c}\mathrm{\Δ}{T}_{12}={\mathrm{dt}}_1-{\mathrm{dt}}_2\\ \mathrm{\Δ}{T}_{43}={\mathrm{dt}}_4-{\mathrm{dt}}_3\\ \mathrm{\Δ}{T}_{14}={\mathrm{dt}}_1-{\mathrm{dt}}_4\\ \mathrm{\Δ}{T}_{23}={\mathrm{dt}}_2-{\mathrm{dt}}_3\end{array}\right.---\left(9\right)$

On this basis, have

$\left\{\begin{array}{c}{d}_1-d_2=v\·\mathrm{\Δ}{T}_{12}\\ d_4-d_3=v\·\mathrm{\Δ}{T}_{43}\\ d_1-d_4=v\·\mathrm{\Δ}{T}_{14}\\ d_2-d_3=v\·\mathrm{\Δ}{T}_{23}\end{array}\right.---\left(10\right)$

The result of (10) being tried to achieve substitutes into (7) and (8) and solves the coordinate (x that can obtain discharge source, y), the position angle (with reference to polar coordinates rule, being 0 ° with horizontal right direction) of discharge source and the radial distance of discharge source distance detection system can be obtained on this basis;

Location algorithm schematic diagram as shown in Figure 3;

Consider that the position of discharge source can affect solving of Hyperbolic Equation group (7) and (8) to a certain extent, as when discharge source position horizontal ordinate is with when in figure, 1,2 antenna horizontal ordinates are identical, to be difficult to utilize formula (7) to position, therefore in algorithm for different quadrant and diverse location mistiming Δ T ₁₂, Δ T ₄₃, Δ T ₁₄, Δ T ₂₃feature, plane be divided into some regions to carry out corresponding special processing:

1) 0 ° and 180 °

When discharge source is positioned at the horizontal front-right of detection system or horizontal front-left, its Δ T ₁₄, Δ T ₂₃be almost 0, now the horizontal ordinate of discharge source can directly be determined, by Δ T ₁₂or Δ T ₄₃positive and negatively can determine position angle, discharge source place, directly can determine its radial distance by (7) formula subsequently, owing to may there is certain error in the searching of waveform starting point, be therefore Δ T ₁₄with Δ T ₂₃retain certain threshold degree, in the scope being less than this threshold degree, can think that it approximates 0, and process according to the method described above;

2) 90 ° and 270 °

When discharge source is positioned at detection system dead ahead or dead astern, its Δ T ₁₂or Δ T ₄₃be almost 0, now the ordinate of discharge source can directly be determined, similar with (1), by Δ T ₁₄or Δ T ₂₃the positive and negative position angle can determining discharge source place, determine its radial distance by (8) formula subsequently;

3) I quadrant

As Δ T ₁₂>0 and Δ T ₂₃during <0, the position of discharge source is in I quadrant, and its angular range is (0 °, 90 °), in I quadrant, there is b ₁₂=0 and b ₂₃the region of=0, meets when the mistiming for this reason

|v·ΔT ₁₂|≈L ₁₂

Or | v Δ T ₂₃| ≈ L ₂₃(11)

Time, directly can determine that a coordinate figure of discharge source is consistent with the coordinate of antenna, and then substitute into formula (7) or formula (8) determine that another coordinate completes location, if the mistiming does not meet the relation represented by (11), then direct solution Nonlinear System of Equations asks for positioning result;

4) II quadrant

As Δ T ₁₂<0 and Δ T ₂₃during <0, the position of discharge source is in II quadrant, and its angular range is (90 °, 180 °), similar with I quadrant, in II quadrant, there is b ₁₂=0 and b ₁₄the region of=0, meets when the mistiming for this reason

|v·ΔT ₁₂|≈L ₁₂

Or | v Δ T ₁₄| ≈ L ₁₄(12)

Time, directly can determine a coordinate figure of discharge source, and then determine its another coordinate, if the mistiming does not meet the relation represented by (12), then direct solution Nonlinear System of Equations asks for positioning result;

5) III quadrant

As Δ T ₁₂<0 and Δ T ₂₃during >0, the position of discharge source is in III quadrant, and its angular range is (180 °, 270 °).Meet when the mistiming in III quadrant

|v·ΔT ₄₃|≈L ₄₃

Or | v Δ T ₁₄| ≈ L ₁₄(13)

Time, can b be caused ₄₃=0 or b ₁₄=0, now directly determine a coordinate figure of discharge source, and then substitution equation determines its position, if the mistiming does not meet (13) described relation, then direct solution system of equations;

6) IV quadrant

As Δ T ₁₂>0 and Δ T ₂₃during >0, the position of discharge source is in IV quadrant, and its angular range is (270 °, 360 °), meets in III quadrant when the mistiming

|v·ΔT ₄₃|≈L ₄₃

Or | v Δ T ₂₃| ≈ L ₂₃(14)

Time, can b be caused ₄₃=0 or b ₂₃=0, now directly determine a coordinate figure of discharge source, and then substitution equation determines its position, if the mistiming does not meet (14) described relation, then direct solution system of equations;

Through above-mentioned classification, the position of discharge source has been divided into several regions, passes through the region that the tried to achieve mistiming determines its place, then completes corresponding location, so just by the area reduction of location, improves the accuracy of location;

When solving (7) with (8) two Nonlinear System of Equations, Newton iteration method is adopted to solve, as write (7) system of equations as vector equation form, wherein X=(x, y) ^t, have

$\stackrel{\&RightArrow;}{F}\left(X\right)=\left(\begin{array}{c}\frac{x^2}{a_{12}^2}-\frac{y^2}{b_{12}^2}-1\\ \frac{x^2}{a_{43}^2}-\frac{y^2}{b_{43}^2}-1\end{array}\right)\stackrel{\mathrm{\&Delta;}}{=}\left(\begin{array}{c}{f}_1\left(X\right)\\ f_2\left(X\right)\end{array}\right)---\left(15\right)$

If X _k=(x _k, y _k) ^tfor an approximate solution of system of equations, then to i=1,2 have

$f_i\left(X\right)\&ap;f_i\left(X_k\right)+\frac{\&PartialD;f_i\left(X_k\right)}{\&PartialD;x_k}(x-x_k)+\frac{\&PartialD;f_i\left(X_k\right)}{\&PartialD;y_k}(y-y_k)---\left(16\right)$

Being write as vector form is

$\stackrel{\&RightArrow;}{F}\left(X\right)\&ap;\stackrel{\&RightArrow;}{F}\left(X_k\right)+{\stackrel{\&RightArrow;}{F}}^{\&prime;}\left(X_k\right)(X-X_k)---\left(17\right)$

Wherein for jacobi matrix at X _kthe value at place.If X value is the root X of system of equations (4-23) ^*, namely using make formula (17) right-hand member be the vectorial X of 0 as new approximate value, be designated as X _k+1, namely have:

$X_{k+1}=X_k-{\left({\stackrel{\&RightArrow;}{F}}^{\&prime;}\left(X_k\right)\right)}^{-1}\stackrel{\&RightArrow;}{F}\left(X_k\right)(---\left(18\right)$

Formula (18) is the iterative formula that newton solves Nonlinear System of Equations.

When using Newton iteration method to solve Nonlinear System of Equations, if choose suitable iterative initial value, effectively can improve arithmetic speed, shorten operation time.Utilize hyperbolic curve by unlimited near this feature of its asymptotic line, under the prerequisite of known point of discharge place quadrant, ask for corresponding two lists and prop up hyp asymptotic line intersection point, and in this, as iterative initial value, this initial value can be made to a certain extent as far as possible near solution of equations, thus improve iteration efficiency.

The beneficial effect of technique scheme is: 1, the testing device for insulation defect of converting station electric power equipment of the present invention have flexible, detect feature quickly and easily; 2, these apparatus and method can carry out discharge examination and plane positioning to defectiveness equipment in transformer station, greatly reduce the cost of substation equipment discharge examination, find defect in advance when contributing to patrolling and examining substation equipment, reduce the generation of power outage, thus improve the intelligent level of transformer station; 3, first the present invention roughly selects defective equipment or part of appliance by this device, determine to carry out again analysing in depth and locating after equipment or part of appliance have had defect pipelines risk, have to transformer station to be measured entirely stand electric discharge detection and positioning fast, cost is low, the feature that efficiency is high.

These apparatus and method can be discharged to defect equipment in transformer station and be detected fast and plane positioning, greatly reduce the cost of substation equipment discharge examination, find defect in advance when contributing to patrolling and examining substation equipment, reduce the generation of power outage, thus improve the intelligent level of transformer station.Have to transformer station to be measured entirely stand electric discharge detection and positioning fast, cost is low, the feature that efficiency is high.

Accompanying drawing explanation

Fig. 1 is that the discharging detection device of packaged type converting station electric power equipment realizes theory diagram;

Fig. 2 is location algorithm schematic diagram (vertical view);

Fig. 3 is ultrahigh frequency electromagnetic wave signal collection;

Fig. 4 is the energy accumulation curve one of ultrahigh-frequency signal;

Fig. 5 is the energy accumulation curve two of ultrahigh-frequency signal;

Fig. 6 is laboratory simulations antenna putting position schematic diagram (unit: m);

Fig. 7 is (unit: m) of rig-site utilization antenna coordinate system.

Embodiment

Illustrate according to the specific embodiment of the present invention below in conjunction with accompanying drawing.

Set forth a lot of detail in the following description so that fully understand the present invention, but the present invention can also adopt other to be different from other modes described here and implement, and therefore, the present invention is not limited to the restriction of following public specific embodiment.

Substation field is fixing starts working apparatus of the present invention after a certain location moving to, according to office's electric discharge magnetic wave signal message that four superfrequency omnidirectional sensors receive, to power transmission and transformation primary equipment all kinds of in transformer station, comprise the discharge signal produced before insulation fault appears in GIS outlet casing tube, transformer high-voltage bushing, SF6 isolating switch, mutual inductor, capacitor, lightning arrester and insulator etc., carry out the testing inspection under electriferous state and research and analyse, realizing the target of discharge examination and breakdown location.

Fig. 1 is that the apparatus insulated defect detecting device of converting station electric power realizes theory diagram, the initial time that same discharge source gives off electric wave signal is received by calculating four superfrequency omnidirectional sensors in real time, poor based on the signal time received, list system of equations, solve the position of discharge signal.

Transformer station provided by the invention defect power equipment device for fast detecting, be made up of superfrequency omnidirectional sensor reception amplification module 1, Ultrahigh speed data sampling unit 2 and data processing unit 3 and analytic unit 4, described superfrequency omnidirectional sensor receives the conglomerate that amplification module 1 is four omnidirectional wideband antennas and wideband pre-amplifier thereof, described superfrequency omnidirectional sensor receives converting station electric power equipment deficiency to be measured and to discharge the electromagnetic wave produced, through described wideband pre-amplifier amplify and after filtering process by described ultra-high-speed data acquisition unit 2 synchronous acquisition;

Described data processing unit 3 carries out data processing unit to four road signals, and emphasis is the time delay of calculating four road signal, thus calculates the planimetric position of discharge source in transformer station.

Preferably, the bandwidth of described wideband pre-amplifier is 1GHz, and gain is 40dB.

Preferably, described Ultrahigh speed data sampling unit 2 is the data collecting card of >3Gsps.

Preferably, described data processing unit 3 is industrial control computer.

Invention also provides and a kind ofly utilize arbitrary described transformer station's defect power equipment device for fast detecting in technique scheme to carry out the method for discharge source detection, comprise step one multichannel electric wave signal synchronous collection, step 2 adopts the time delay of bi-spectrum estimation algorithm determination two-way electric wave signal and step 3 to utilize time-delay calculation to discharge the planimetric position of source point;

Step one multichannel electric wave signal synchronous collection

By described transformer station defect power equipment device for fast detecting after a certain position of transformer station to be measured is placed, after described pick-up unit starts, described hyperchannel superfrequency omnidirectional sensor receives the electromagnetic wave signal that transformer station's defect power equipment produces because of electric discharge, amplify through described wideband pre-amplifier and carry out synchronous acquisition by described ultra-high-speed data acquisition unit after filtering process, sending described data processing unit to carry out data processing unit to multiple signals;

Step 2 adopts the time delay of bi-spectrum estimation algorithm determination two-way electric wave signal

The two paths of signals simultaneously collected by the digital acquisition system of signal is respectively discrete series { x1 (n) } and { x2 (n) }, in conjunction with Higher Order Cumulants theory, utilize the computer numerical implementation method of parameter two spectrum Time Delay Estimation Algorithms, calculate sub-step as follows

Sub-step 1: same to conventional Calculation Method, is divided into K section by the signal data sample observed, every section comprises M observation sample, is denoted as respectively wherein k=1,2 ..., k, i=1,2, can coincidence be had between adjacent two segment datas;

Sub-step 2: calculate every segment signal from Third-order cumulants and mutual Third-order cumulants:

${\hat{c}}_{x_1{x}_1{x}_1}^{\left(k\right)}(\mathrm{\&tau;},\mathrm{\&rho;})=\frac{1}{M}\underset{n=S_1}{\overset{S_2}{\mathrm{\&Sigma;}}}{x}_1^{\left(k\right)}\left(n\right)x_1^{\left(k\right)}(n+\mathrm{\&tau;})x_1^{\left(k\right)*}(n+\mathrm{\&rho;})$

${\hat{c}}_{x_1{x}_2{x}_1}^{\left(k\right)}(\mathrm{\&tau;},\mathrm{\&rho;})=\frac{1}{M}\underset{n=S_1}{\overset{S_2}{\mathrm{\&Sigma;}}}{x}_1^{\left(k\right)}\left(n\right)x_2^{\left(k\right)}(n+\mathrm{\&tau;})x_1^{\left(k\right)*}(n+\mathrm{\&rho;})---\left(1\right)$

Wherein, S1 and S2 respectively value be:

S ₁＝max(0,-τ,-ρ)

S ₂＝min(M-1,M-1-τ,M-1-ρ)

Sub-step 3: calculate the mean value of each segment signal from Third-order cumulants and mutual Third-order cumulants, the Third-order cumulants as whole segment signal is estimated:

${\hat{C}}_{x_1{x}_1{x}_1}(\mathrm{\&tau;},\mathrm{\&rho;})=\frac{1}{K}\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}{\hat{c}}_{x_1{x}_1{x}_1}^{\left(k\right)}(\mathrm{\&tau;},\mathrm{\&rho;})$

${\hat{C}}_{x_1{x}_2{x}_1}(\mathrm{\&tau;},\mathrm{\&rho;})=\frac{1}{K}\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}{\hat{c}}_{x_1{x}_2{x}_1}^{\left(k\right)}(\mathrm{\&tau;},\mathrm{\&rho;})---\left(3\right)$

Sub-step 4: utilize with write out matrix and vector and list system of equations:

${\hat{C}}_{x_1{x}_1{x}_1}={\hat{C}}_{x_1{x}_2{x}_1}A---\left(4\right)$

Wherein

$C_{x_1{x}_2{x}_1}={[c_{x_1{x}_2{x}_1}(-p,0),...,c_{x_1{x}_2{x}_1}(p,0),c_{x_1{x}_2{x}_1}(-p,1),...,c_{x_1{x}_2{x}_1}(p,1),c_{x_1{x}_2{x}_1}(-p,-1),...,c_{x_1{x}_2{x}_1}(p,-1)]}^T$

A＝[a _-p,a _-p+1,…,0,…,a _p-1,a _p] ^T

Sub-step 5: utilize least square method to solve above-mentioned system of equations, estimate vector

$\hat{A}={\left({\hat{C}}_{x_1{x}_1{x}_1}^T{\hat{C}}_{x_1{x}_1{x}_1}\right)}^{-1}{\hat{C}}_{x_1{x}_1{x}_1}^T{\hat{C}}_{x_1{x}_2{x}_1}---\left(5\right)$

Wherein to make get the index value d of maximal value, as the estimation of two paths of signals time delay

Step 3 utilizes the planimetric position of time-delay calculation electric discharge source point

Native system considers that power equipment is all floor plan in transformer station, determine the power equipment of possibility existing defects, only need calculate the planimetric position of discharge source in transformer station, sensor array adopts planar rectangular arrangement mode for this reason, supposes that the position coordinates of four sensors in plane coordinate system is respectively (x ₁, y ₁), (x ₂, y ₂), (x ₃, y ₃) and (x ₄, y ₄), discharge source position is (x, y), and the distance between discharge source and four sensors is respectively d ₁, d ₂, d ₃and d ₄, namely

$d_i=\sqrt{{(x-x_i)}^2+{(y-y_i)}^2},i=\mathrm{1,2,3,4}---\left(6\right)$

According to plane analytic geometry knowledge, the range difference (d between discharge source to every two sensors _i-d _j) uniquely can determine that a list props up hyperbolic curve, therefore, take antenna array center as planimetric rectangular coordinates initial point, point of discharge place quadrant can be determined by the mistiming, utilize the list of equidirectional to prop up Hyperbolic Equation simultaneous and can obtain following Nonlinear System of Equations:

$\left\{\begin{array}{c}\frac{x^2}{a_{12}^2}-\frac{y^2}{b_{12}^2}=1\\ \frac{x^2}{a_{43}^2}-\frac{y^2}{b_{43}^2}=1\end{array}\right.---\left(7\right)$

$\left\{\begin{array}{c}\frac{x^2}{a_{14}^2}-\frac{y^2}{b_{14}^2}=1\\ \frac{x^2}{a_{23}^2}-\frac{y^2}{b_{23}^2}=1\end{array}\right.---\left(8\right)$

A in formula _ij=(d _i-d _j)/2---hyp semi-major axis is long;

---hyp semi-minor axis long square;

C _ij---hyperbolic curve focal length, can obtain according to the size of aerial array;

Suppose that the waveform initial time of four road discharge signals is respectively dt ₁, dt ₂, dt ₃and dt ₄, discharge signal is transmitted to the mistiming Δ T of different antennae ₁₂, Δ T ₄₃, Δ T ₁₄, Δ T ₂₃can be expressed as

$\left\{\begin{array}{c}\mathrm{\&Delta;}{T}_{12}={\mathrm{dt}}_1-{\mathrm{dt}}_2\\ \mathrm{\&Delta;}{T}_{43}={\mathrm{dt}}_4-{\mathrm{dt}}_3\\ \mathrm{\&Delta;}{T}_{14}={\mathrm{dt}}_1-{\mathrm{dt}}_4\\ \mathrm{\&Delta;}{T}_{23}={\mathrm{dt}}_2-{\mathrm{dt}}_3\end{array}\right.---\left(9\right)$

On this basis, have

$\left\{\begin{array}{c}{d}_1-d_2=v\&CenterDot;\mathrm{\&Delta;}{T}_{12}\\ d_4-d_3=v\&CenterDot;\mathrm{\&Delta;}{T}_{43}\\ d_1-d_4=v\&CenterDot;\mathrm{\&Delta;}{T}_{14}\\ d_2-d_3=v\&CenterDot;\mathrm{\&Delta;}{T}_{23}\end{array}\right.---\left(10\right)$

The result of (10) being tried to achieve substitutes into (7) and (8) and solves the coordinate (x that can obtain discharge source, y), the position angle (with reference to polar coordinates rule, being 0 ° with horizontal right direction) of discharge source and the radial distance of discharge source distance detection system can be obtained on this basis;

Fig. 3 is location algorithm schematic diagram (vertical view).

Location algorithm schematic diagram as shown in Figure 3.

Consider that the position of discharge source can affect solving of Hyperbolic Equation group (7) and (8) to a certain extent, as when discharge source position horizontal ordinate is with when in figure, 1,2 antenna horizontal ordinates are identical, to be difficult to utilize formula (7) to position, therefore in algorithm for different quadrant and diverse location mistiming Δ T ₁₂, Δ T ₄₃, Δ T ₁₄, Δ T ₂₃feature, plane be divided into some regions to carry out corresponding special processing:

1) 0 ° and 180 °

When discharge source is positioned at the horizontal front-right of detection system or horizontal front-left, its Δ T ₁₄, Δ T ₂₃be almost 0, now the horizontal ordinate of discharge source can directly be determined, by Δ T ₁₂or Δ T ₄₃positive and negatively can determine position angle, discharge source place, directly can determine its radial distance by (7) formula subsequently, owing to may there is certain error in the searching of waveform starting point, be therefore Δ T ₁₄with Δ T ₂₃retain certain threshold degree, in the scope being less than this threshold degree, can think that it approximates 0, and process according to the method described above;

2) 90 ° and 270 °

When discharge source is positioned at detection system dead ahead or dead astern, its Δ T ₁₂or Δ T ₄₃be almost 0, now the ordinate of discharge source can directly be determined, similar with (1), by Δ T ₁₄or Δ T ₂₃the positive and negative position angle can determining discharge source place, determine its radial distance by (8) formula subsequently;

3) I quadrant

As Δ T ₁₂>0 and Δ T ₂₃during <0, the position of discharge source is in I quadrant, and its angular range is (0 °, 90 °), in I quadrant, there is b ₁₂=0 and b ₂₃the region of=0, meets when the mistiming for this reason

|v·ΔT ₁₂|≈L ₁₂

Or | v Δ T ₂₃| ≈ L ₂₃(11)

Time, directly can determine that a coordinate figure of discharge source is consistent with the coordinate of antenna, and then substitute into formula (7) or formula (8) determine that another coordinate completes location, if the mistiming does not meet the relation represented by (11), then direct solution Nonlinear System of Equations asks for positioning result;

4) II quadrant

As Δ T ₁₂<0 and Δ T ₂₃during <0, the position of discharge source is in II quadrant, and its angular range is (90 °, 180 °), similar with I quadrant, in II quadrant, there is b ₁₂=0 and b ₁₄the region of=0, meets when the mistiming for this reason

|v·ΔT ₁₂|≈L ₁₂

Or | v Δ T ₁₄| ≈ L ₁₄(12)

Time, directly can determine a coordinate figure of discharge source, and then determine its another coordinate, if the mistiming does not meet the relation represented by (12), then direct solution Nonlinear System of Equations asks for positioning result;

5) III quadrant

As Δ T ₁₂<0 and Δ T ₂₃during >0, the position of discharge source is in III quadrant, and its angular range is (180 °, 270 °).Meet when the mistiming in III quadrant

|v·ΔT ₄₃|≈L ₄₃

Or | v Δ T ₁₄| ≈ L ₁₄(13)

Time, can b be caused ₄₃=0 or b ₁₄=0, now directly determine a coordinate figure of discharge source, and then substitution equation determines its position, if the mistiming does not meet (13) described relation, then direct solution system of equations;

6) IV quadrant

As Δ T ₁₂>0 and Δ T ₂₃during >0, the position of discharge source is in IV quadrant, and its angular range is (270 °, 360 °), meets in III quadrant when the mistiming

|v·ΔT ₄₃|≈L ₄₃

Or | v Δ T ₂₃| ≈ L ₂₃(14)

Time, can b be caused ₄₃=0 or b ₂₃=0, now directly determine a coordinate figure of discharge source, and then substitution equation determines its position, if the mistiming does not meet (14) described relation, then direct solution system of equations;

Through above-mentioned classification, the position of discharge source has been divided into several regions, passes through the region that the tried to achieve mistiming determines its place, then completes corresponding location, so just by the area reduction of location, improves the accuracy of location;

When solving (7) with (8) two Nonlinear System of Equations, Newton iteration method is adopted to solve, as write (7) system of equations as vector equation form, wherein X=(x, y) ^t, have

$\stackrel{\&RightArrow;}{F}\left(X\right)=\left(\begin{array}{c}\frac{x^2}{a_{12}^2}-\frac{y^2}{b_{12}^2}-1\\ \frac{x^2}{a_{43}^2}-\frac{y^2}{b_{43}^2}-1\end{array}\right)\stackrel{\mathrm{\&Delta;}}{=}\left(\begin{array}{c}{f}_1\left(X\right)\\ f_2\left(X\right)\end{array}\right)---\left(15\right)$

If X _k=(x _k, y _k) ^tfor an approximate solution of system of equations, then to i=1,2 have

$f_i\left(X\right)\&ap;f_i\left(X_k\right)+\frac{\&PartialD;f_i\left(X_k\right)}{\&PartialD;x_k}(x-x_k)+\frac{\&PartialD;f_i\left(X_k\right)}{\&PartialD;y_k}(y-y_k)---\left(16\right)$

Being write as vector form is

$\stackrel{\&RightArrow;}{F}\left(X\right)\&ap;\stackrel{\&RightArrow;}{F}\left(X_k\right)+{\stackrel{\&RightArrow;}{F}}^{\&prime;}\left(X_k\right)(X-X_k)---\left(17\right)$

Wherein for jacobi matrix at X _kthe value at place.If X value is the root X of system of equations (4-23) ^*, namely using make formula (17) right-hand member be the vectorial X of 0 as new approximate value, be designated as X _k+1, namely have:

$X_{k+1}=X_k-{\left({\stackrel{\&RightArrow;}{F}}^{\&prime;}\left(X_k\right)\right)}^{-1}\stackrel{\&RightArrow;}{F}\left(X_k\right)(---\left(18\right)$

Formula (18) is the iterative formula that newton solves Nonlinear System of Equations.

When using Newton iteration method to solve Nonlinear System of Equations, if choose suitable iterative initial value, effectively can improve arithmetic speed, shorten operation time.Utilize hyperbolic curve by unlimited near this feature of its asymptotic line, under the prerequisite of known point of discharge place quadrant, ask for corresponding two lists and prop up hyp asymptotic line intersection point, and in this, as iterative initial value, this initial value can be made to a certain extent as far as possible near solution of equations, thus improve iteration efficiency.

The beneficial effect of technique scheme is: 1, the testing device for insulation defect of converting station electric power equipment of the present invention have flexible, detect feature quickly and easily; 2, these apparatus and method can carry out discharge examination and plane positioning to defectiveness equipment in transformer station, greatly reduce the cost of substation equipment discharge examination, find defect in advance when contributing to patrolling and examining substation equipment, reduce the generation of power outage, thus improve the intelligent level of transformer station; 3, first the present invention roughly selects defective equipment or part of appliance by this device, determine to carry out again analysing in depth and locating after equipment or part of appliance have had defect pipelines risk, have to transformer station to be measured entirely stand electric discharge detection and positioning fast, cost is low, the feature that efficiency is high.

These apparatus and method can be discharged to defect equipment in transformer station and be detected fast and plane positioning, greatly reduce the cost of substation equipment discharge examination, find defect in advance when contributing to patrolling and examining substation equipment, reduce the generation of power outage, thus improve the intelligent level of transformer station.Have to transformer station to be measured entirely stand electric discharge detection and positioning fast, cost is low, the feature that efficiency is high.

Fig. 3 is ultrahigh frequency electromagnetic wave signal collection, Fig. 4 is the energy accumulation curve one of ultrahigh-frequency signal, Fig. 5 is the energy accumulation curve two of ultrahigh-frequency signal, Fig. 6 is that (unit: m), Fig. 7 is (unit: m) of rig-site utilization antenna coordinate system to laboratory simulations antenna putting position schematic diagram.

Laboratory test and checking

Laboratory simulations checking location algorithm antenna placing space position is as shown in the coordinate points A in Fig. 6, B, C, D, and antenna, at same plane, is placed on rectangular four summits; Simulation discharge source P point position is (0.35,3.86,2.28) m.Apply above-mentioned location algorithm, the positioning result obtained is as shown in table 1.

x(m)	0.36	0.32	0.36	0.36	0.36	0.36
							y(m)	4.00	4.10	4.00	4.00	4.00	4.00
z(m)	2.40	2.52	2.46	2.40	2.40	2.40

Table 1

In table 1, the mean place of 6 groups of positioning results is (0.35,4.02,2.43) m, and the simulation discharge source P point position of reality is (0.35,3.86,2.28) m, absolute error is (0.00,0.16,0.15) m, consider that antenna radius, ground unrest, known location measure time difference calculating equal error producing cause, positioning result meets the requirement that equipment of putting of playing a game positions.

Rig-site utilization is verified

For the effect run under verification system at the scene strong interference environment, the testing experiment of system has been carried out in certain 500kV transformer station, superfrequency omnidirectional sensor is arranged on moveable support, installs the coordinate of aft antenna as shown in Figure 7, and manufacture simulation discharge source is verified.Collect the ultrahigh frequency electromagnetic wave signal data that discharge source sends, calculate through system Treatment Analysis and location algorithm, result orientation discharge source at the scene coordinate is (5.46,0.68,0.58) m, and the actual position of realistic simulation discharge source is probably (5.3,0.7,0.6) about m, error, within 2%, meets the requirement of converting station electric power equipment current potential positioning precision.

Our experiments show that, the present invention can carry out omnibearing discharge examination and location to all devices in transformer station, greatly reduce the cost of substation equipment discharge examination, defect is found in advance when contributing to patrolling and examining substation equipment, reduce the generation of power outage, thus improve the intelligent level of transformer station.Have to transformer station to be measured entirely stand electric discharge detection and positioning fast, cost is low, the feature that efficiency is high.

The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (5)

1. transformer station's defect power equipment device for fast detecting, it is characterized in that, be made up of superfrequency omnidirectional sensor reception amplification module, Ultrahigh speed data sampling unit and data processing unit and analytic unit, described superfrequency omnidirectional sensor receives the conglomerate that amplification module is four omnidirectional wideband antennas and wideband pre-amplifier thereof, described superfrequency omnidirectional sensor receives converting station electric power equipment deficiency to be measured and to discharge the electromagnetic wave produced, through described wideband pre-amplifier amplify and after filtering process by described ultra-high-speed data acquisition units synchronization collection;

Described data processing unit carries out data processing unit to four road signals, and emphasis is the time delay of calculating four road signal, thus calculates the planimetric position of discharge source in transformer station.

2. transformer station's defect power equipment device for fast detecting according to claim 1, is characterized in that: the bandwidth of described wideband pre-amplifier is 1GHz, and gain is 40dB.

3. transformer station's defect power equipment device for fast detecting according to claim 1, is characterized in that: described Ultrahigh speed data sampling unit is the data collecting card of >3Gsps.

4. transformer station's defect power equipment device for fast detecting according to claim 1, is characterized in that: described data processing unit is industrial control computer.

5. utilize arbitrary described transformer station defect power equipment device for fast detecting in claim 1 to 4 to carry out a method for discharge source detection, it is characterized in that comprising step one multichannel electric wave signal synchronous collection, step 2 adopts the time delay of bi-spectrum estimation algorithm determination two-way electric wave signal and step 3 to utilize time-delay calculation to discharge the planimetric position of source point;

Step one multichannel electric wave signal synchronous collection

By described transformer station defect power equipment device for fast detecting after a certain position of transformer station to be measured is placed, after described pick-up unit starts, described hyperchannel superfrequency omnidirectional sensor receives the electromagnetic wave signal that transformer station's defect power equipment produces because of electric discharge, amplify through described wideband pre-amplifier and carry out synchronous acquisition by described ultra-high-speed data acquisition unit after filtering process, sending described data processing unit to carry out data processing unit to multiple signals;

Step 2 adopts the time delay of bi-spectrum estimation algorithm determination two-way electric wave signal

The two paths of signals simultaneously collected by the digital acquisition system of signal is respectively discrete series { x1 (n) } and { x2 (n) }, in conjunction with Higher Order Cumulants theory, utilize the computer numerical implementation method of parameter two spectrum Time Delay Estimation Algorithms, calculate sub-step as follows

Sub-step 1: same to conventional Calculation Method, is divided into K section by the signal data sample observed, every section comprises M observation sample, is denoted as respectively wherein k=1,2 ..., k, i=1,2, can coincidence be had between adjacent two segment datas;

Sub-step 2: calculate every segment signal from Third-order cumulants and mutual Third-order cumulants:

Wherein, S1 and S2 respectively value be:

S ₁＝max(0,-τ,-ρ)

S ₂＝min(M-1,M-1-τ,M-1-ρ)

Sub-step 3: calculate the mean value of each segment signal from Third-order cumulants and mutual Third-order cumulants, the Third-order cumulants as whole segment signal is estimated:

Sub-step 4: utilize with write out matrix and vector and list system of equations:

Wherein

A＝[a _-p,a _-p+1,…,0,…,a _p-1,a _p] ^T

Sub-step 5: utilize least square method to solve above-mentioned system of equations, estimate vector

Wherein to make get the index value d of maximal value, as the estimation of two paths of signals time delay

Step 3 utilizes the planimetric position of time-delay calculation electric discharge source point

Sensor array adopts planar rectangular arrangement mode, supposes that the position coordinates of four sensors in plane coordinate system is respectively (x ₁, y ₁), (x ₂, y ₂), (x ₃, y ₃) and (x ₄, y ₄), discharge source position is (x, y), and the distance between discharge source and four sensors is respectively d ₁, d ₂, d ₃and d ₄, namely

According to plane analytic geometry knowledge, the range difference (d between discharge source to every two sensors _i-d _j) uniquely can determine that a list props up hyperbolic curve, therefore, take antenna array center as planimetric rectangular coordinates initial point, point of discharge place quadrant can be determined by the mistiming, utilize the list of equidirectional to prop up Hyperbolic Equation simultaneous and can obtain following Nonlinear System of Equations:

A in formula _ij=(d _i-d _j)/2---hyp semi-major axis is long;

---hyp semi-minor axis long square;

C _ij---hyperbolic curve focal length, can obtain according to the size of aerial array;

Suppose that the waveform initial time of four road discharge signals is respectively dt ₁, dt ₂, dt ₃and dt ₄, discharge signal is transmitted to the mistiming Δ T of different antennae ₁₂, Δ T ₄₃, Δ T ₁₄, Δ T ₂₃can be expressed as

On this basis, have

The result of (10) being tried to achieve substitutes into (7) and (8) and solves the coordinate (x that can obtain discharge source, y), the position angle (with reference to polar coordinates rule, being 0 ° with horizontal right direction) of discharge source and the radial distance of discharge source distance detection system can be obtained on this basis;

Location algorithm schematic diagram 3 as shown in the figure;

For different quadrant and diverse location mistiming Δ T in algorithm ₁₂, Δ T ₄₃, Δ T ₁₄, Δ T ₂₃feature, plane be divided into some regions to carry out corresponding special processing:

1) 0 ° and 180 °

When discharge source is positioned at the horizontal front-right of detection system or horizontal front-left, its Δ T ₁₄, Δ T ₂₃be almost 0, now the horizontal ordinate of discharge source can directly be determined, by Δ T ₁₂or Δ T ₄₃positive and negatively can determine position angle, discharge source place, directly can determine its radial distance by (7) formula subsequently, owing to may there is certain error in the searching of waveform starting point, be therefore Δ T ₁₄with Δ T ₂₃retain certain threshold degree, in the scope being less than this threshold degree, can think that it approximates 0, and process according to the method described above;

2) 90 ° and 270 °

When discharge source is positioned at detection system dead ahead or dead astern, its Δ T ₁₂or Δ T ₄₃be almost 0, now the ordinate of discharge source can directly be determined, similar with (1), by Δ T ₁₄or Δ T ₂₃the positive and negative position angle can determining discharge source place, determine its radial distance by (8) formula subsequently;

3) I quadrant

As Δ T ₁₂>0 and Δ T ₂₃during <0, the position of discharge source is in I quadrant, and its angular range is (0 °, 90 °), in I quadrant, there is b ₁₂=0 and b ₂₃the region of=0, meets when the mistiming for this reason

|v·ΔT ₁₂|≈L ₁₂

Or | v Δ T ₂₃| ≈ L ₂₃(11)

Time, directly can determine that a coordinate figure of discharge source is consistent with the coordinate of antenna, and then substitute into formula (7) or formula (8) determine that another coordinate completes location, if the mistiming does not meet the relation represented by (11), then direct solution Nonlinear System of Equations asks for positioning result;

4) II quadrant

As Δ T ₁₂<0 and Δ T ₂₃during <0, the position of discharge source is in II quadrant, and its angular range is (90 °, 180 °), similar with I quadrant, in II quadrant, there is b ₁₂=0 and b ₁₄the region of=0, meets when the mistiming for this reason

|v·ΔT ₁₂|≈L ₁₂

Or | v Δ T ₁₄| ≈ L ₁₄(12)

Time, directly can determine a coordinate figure of discharge source, and then determine its another coordinate, if the mistiming does not meet the relation represented by (12), then direct solution Nonlinear System of Equations asks for positioning result;

5) III quadrant

As Δ T ₁₂<0 and Δ T ₂₃during >0, the position of discharge source is in III quadrant, and its angular range is (180 °, 270 °).Meet when the mistiming in III quadrant

|v·ΔT ₄₃|≈L ₄₃

Or | v Δ T ₁₄| ≈ L ₁₄(13)

Time, can b be caused ₄₃=0 or b ₁₄=0, now directly determine a coordinate figure of discharge source, and then substitution equation determines its position, if the mistiming does not meet (13) described relation, then direct solution system of equations;

6) IV quadrant

As Δ T ₁₂>0 and Δ T ₂₃during >0, the position of discharge source is in IV quadrant, and its angular range is (270 °, 360 °), meets in III quadrant when the mistiming

|v·ΔT ₄₃|≈L ₄₃

Or | v Δ T ₂₃| ≈ L ₂₃(14)

Time, can b be caused ₄₃=0 or b ₂₃=0, now directly determine a coordinate figure of discharge source, and then substitution equation determines its position, if the mistiming does not meet (14) described relation, then direct solution system of equations;

When solving (7) with (8) two Nonlinear System of Equations, Newton iteration method is adopted to solve, as write (7) system of equations as vector equation form, wherein X=(x, y) ^t, have

If X _k=(x _k, y _k) ^tfor an approximate solution of system of equations, then to i=1,2 have

Being write as vector form is

Wherein for jacobi matrix at X _kthe value at place.If X value is the root X of system of equations (4-23) ^*, namely using make formula (17) right-hand member be the vectorial X of 0 as new approximate value, be designated as X _k+1, namely have:

Formula (18) is the iterative formula that newton solves Nonlinear System of Equations.