CN106199342B - A kind of wire selection method for power distribution network single phase earthing failure - Google Patents
A kind of wire selection method for power distribution network single phase earthing failure Download PDFInfo
- Publication number
- CN106199342B CN106199342B CN201610834659.6A CN201610834659A CN106199342B CN 106199342 B CN106199342 B CN 106199342B CN 201610834659 A CN201610834659 A CN 201610834659A CN 106199342 B CN106199342 B CN 106199342B
- Authority
- CN
- China
- Prior art keywords
- matrix
- frequency component
- branch line
- power frequency
- zero
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/088—Aspects of digital computing
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Locating Faults (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a kind of wire selection method for power distribution network single phase earthing failure, including step：First, the real-time acquisition of fault-signal；2nd, the collection of fault-signal, storage and analyzing and processing；3rd, the judgement whether singlephase earth fault occurs；4th, the extraction of the non-power frequency component of each branch line zero-sequence current；5th, the selection of faulty line；6th, failure line selection result shows, transmits and alarms.It is of the invention novel in design, step is simple, energy self adaptation complex fault state and heterogeneous networks structure, the non-power frequency component amplitude of zero-sequence current of each branch line is extracted by the way of iteration convergence, failure line selection is carried out with the contrast of critical deviation by absolute value deviation, route selection effect is good, and method is accurate, reliable, and physical significance is apparent.
Description
Technical field
The invention belongs to singlephase earth fault technical field, and in particular to a kind of Single-phase Earth-fault Selection in Distribution Systems side
Method.
Background technology
At present, when there is singlephase earth fault in the system of grounding through arc, if failing effectively to detect fault branch,
Then sustained fault may develop into more serious two-phase or three-phase shortcircuit, be originated according to the signal for utilizing, and existing selection method has
Injecting signal, fault-signal method and information fusion method.Injecting signal is by the way that to power network external signal route selection, its signal source sets
Meter is complicated with control；Fault-signal method detects fault branch using the stable state or transient characteristic of system single-phase earthing；Information fusion
By merging multi-signal and method route selection, the validity for being fused the active domain of method and combinations thereof waits research to method.
Fault-signal method includes stable state route selection and transient line selection, and the steady-state signal that stable state route selection method is utilized is faint, and
There is dead band in the arc suppression coil earthing system of overcompensation, the method application is limited；The failure that fault transient signals are included is special
Levy abundant, if can make full use of, be conducive to route selection.Using transient characteristic route selection aspect, the extraction of high-frequency characteristic is concentrated mainly on.
During with wavelet packet analysis transient zero-sequence amount route selection, wavelet method needs to select Optimum wavelet function, and its selection is difficult；Selected with S-transformation
During line, the transient signal polarity or amplitude Characteristics of certain frequency band are mainly extracted, do not consider further feature；During with transient state travelling wave route selection,
Wavefront instantaneously easily dies, and accurately detects difficult；During with transient DC characterization method route selection, it cannot function as main criterion；With
During transient signal energy route selection, because accumulated error is larger, using limited；During with the otherness route selection of transient state full signal waveform,
Otherness threshold value is difficult determination, influences route selection effect；Transient process complicated mechanism, state are random, particularly glitch angle or height
Under conditions of resistance ground connection, the reliability of existing transient state route selection cannot be guaranteed.In addition, transient signal frequency content is complicated, it is bright
The distribution character of each frequency component is the premise of route selection in true transient signal, and accurate extraction can be used for the fault transient feature of route selection
Signal is the key of route selection.So zero-sequence current composition when power distribution network into singlephase earth fault can occur is divided into power frequency point
Amount and non-power frequency component two parts, wherein, the non-power frequency component of fault branch is more than non-faulting branch road, using this feature recognition
Fault branch.
The content of the invention
The technical problems to be solved by the invention are for above-mentioned deficiency of the prior art, there is provided a kind of power distribution network list
Phase ground fault line selecting method, it is novel in design rationally, and step is simple, can self adaptation complex fault state and heterogeneous networks knot
Structure, extracts the non-power frequency component amplitude of zero-sequence current of each branch line by the way of iteration convergence, by absolute value deviation with it is critical
The contrast of deviation carries out failure line selection, and route selection effect is good, and method is accurate, reliable, and physical significance is apparent, is easy to promote the use of.
In order to solve the above technical problems, the technical solution adopted by the present invention is：A kind of Single-phase Earth-fault Selection in Distribution Systems
Method, it is characterised in that the method is comprised the following steps：
The real-time acquisition of step one, fault-signal：Using line voltage progress of disease circuit real-time detection line voltage and pass through
Line voltage wave filter is filtered denoising, using residual voltage progress of disease circuit real-time detection residual voltage and by zero sequence
Voltage filter is filtered denoising, using multiple each branch line zero-sequence currents of branch line zero-sequence current progress of disease circuit real-time detection
And denoising is filtered by branch line zero sequence current filter respectively；
Step 2, the collection of fault-signal, storage and analyzing and processing：Analog-digital converter is under the control of the micro-controller, right
The zero sequence current signal of line voltage, residual voltage and a plurality of branch line in step one after filtering and noise reduction treatment enters line period and adopts
Sample, and export to microcontroller after signal to being gathered in each sampling period carries out analog-to-digital conversion, microcontroller is connect
The zero sequence current signal of the line voltage, residual voltage and a plurality of branch line of receipts is stored in data storage, and signal is carried out
Analyzing and processing, obtains the virtual value U of the phase voltage of line voltageaWith the virtual value U of residual voltage0；
The judgement whether step 3, singlephase earth fault occur：Microcontroller is analyzed and processed half cycle for obtaining
The virtual value U of interior multiple residual voltages0With the power network residual voltage threshold value U of settingOP=0.15UaCompare, work as U0≥Uop
When, it is judged as that singlephase earth fault occurs, perform step 4；Otherwise, as multiple power network residual voltage U0In have less than power network zero
Sequence voltage threshold value UopWhen, return to step two；
The extraction of step 4, the non-power frequency component of each branch line zero-sequence current：Microcontroller is to each branch line zero sequence in step 2
The non-power frequency component of electric current is extracted, and microcontroller is equal to the extraction process of the non-power frequency component of the zero-sequence current of any branch line
It is identical, obtain amplitude coefficient vectorWherein, N is branch line number and N >=2, ajIt is any branch line
Branch line zero-sequence current non-power frequency component amplitude, 1≤j≤N；
Amplitude a of the microcontroller to the non-power frequency component of the zero-sequence current of any branch linejDuring extraction, process is as follows：
The observation signal matrix X of step 401, construction branch line zero-sequence current：Microcontroller is using latter cycle of failure
Branch line zero-sequence current i0Data configuration branch line zero-sequence current observation signal matrixWherein, M is the sampling number in a cycle T
And M >=1, TsIt is the sampling time interval of two neighboring sampled point,i0(qTs) it is q-th zero-sequence current of sampled point
Sampled value, sin (q ω Ts) for unit power frequency component sinusoidal virtual observation signal sin (ω t) q-th sample point from
Dissipate value, cos (q ω Ts) it is cosine virtual observation signal cos (ω t) of unit power frequency component in the discrete of q-th sample point
Value, q=1,2 ..., M；
The centralization of step 402, observation signal matrix X：Microcontroller is obtained to observation signal matrix X centralizations treatment
Centralization matrix
Step 403, centralization matrixAlbefaction：Microcontroller is to the centralization matrix in step 402Whitening processing,
Obtain whitening matrix Z；
Step 404, iteration initialization：W (k) is initialized by microcontroller, even k=0 arbitrarily takes W (0) and meets | | W
(0)||2=1, W (k) is the kth time iteration of the mixed matrix W of solution, wherein, W is the mixed matrix of solution of n × n dimensions, k=0,1 ... ..., M, n
It is observation signal matrix line number；
Step 405, basisEnter
Row iteration process, wherein, λ is nonlinear function and G (x)=tan (a for the damping factor and 0 ＜ λ ＜ 1, G of iteration1X), a1For
The variation coefficient and 1≤a of nonlinear function G1≤ 2, β are constant, and E (Y) is the average of variable data Y；
Step 406, according to formula W (k+1) ← W (k+1)/| | W (k+1) | |, to the mixed matrix W (k+1) of solution in step 405
It is normalized；
Step 407, judge whether W (k+1) restrains and obtain the mixed matrix W of solution：Microcontroller limits ε and differentiates according to convergence error
Convergence, when | W (k+1)-W (k) | ＞ ε and iterations are less than M, W (k+1) is not converged, performs step 405；Otherwise, W=W (k are taken
+ 1) step 408, is performed；
The acquisition of step 408, the amplitude coefficient of the non-power frequency component of branch line zero-sequence current：First, according to formula A=W-1,
Calculate the hybrid matrix A of branch line；Then, the corresponding element a of non-power frequency component in the first row element is extracted in hybrid matrix A1i, obtain
To the amplitude a of the non-power frequency component of branch line zero-sequence currentj=| a1i|, i=1,2 ..., n；
The selection of step 5, faulty line, process is as follows：
Step 501, calculating absolute deviationWherein, agFor the greatest member in amplitude coefficient vector a and It is not comprising agAverage value and
Step 502, calculate critical deviation s σ, wherein, s is t distribution inspection coefficients, σ be standard deviation and
Step 503, selection faulty line：WhenWhen, there is earth fault in bus；Otherwise, branch line connects
Greatest member is in earth fault, and amplitude coefficient vector aCorresponding branch line is faulty line；
Step 6, failure line selection result show, transmit and alarm：Microcontroller shows event by liquid crystal display circuit module
Barrier route selection result simultaneously passes through ethernet communication module to host computer transmission fault route selection object information, by switching value output module
Output trip command, the timely alarm faulty line of alarm module.
A kind of above-mentioned wire selection method for power distribution network single phase earthing failure, it is characterised in that：By branch line zero sequence electricity in step 408
The stream isolated X=AS of X, wherein, S is the matrix that source signal and S are tieed up for n × M, and n row vector is distinguished using frequency algorithm in S
Go out non-power frequency component and power frequency component, extract in hybrid matrix A the corresponding element a of non-power frequency component in the first row element1i, mistake
Journey is as follows：
Step Ι, selection frequency calculate sampled point：Microcontroller searches sampled point in half cycle that it is analyzed and processed
Sid、WithWherein, SidIt is the corresponding electric current of d-th discrete point in the i-th row vector in isolated source signal S
Value,It is and SidIntervalThe corresponding current value of discrete point of cycle,It is and SidIntervalThe discrete point pair of cycle
The current value answered, and 0≤d≤M；
Step Ι Ι, according to formulaMeter
Calculate
Step Ι Ι Ι, judge source signal S in the i-th row vector whether be non-power frequency component：When in step Ι ΙWhen, the f being calculated is non-power frequency component, now, determines row sequence number i in source signal S, then hybrid matrix A
In corresponding element a in the first row element1iIt is the corresponding amplitude size of non-power frequency component, completes the non-work of the branch line zero-sequence current
The acquisition of the amplitude of frequency component；Otherwise, step Ι V are performed；
Next row vector is used as the i-th row vector in source signal S, repeat step Ι to step Ι in step Ι V, selection source signal S
ΙΙ。
A kind of above-mentioned wire selection method for power distribution network single phase earthing failure, it is characterised in that：Microcontroller described in step 402
To observation signal matrix X centralizations treatment, process is as follows：
Step a, according to formulaObtain the average value X of observation signal matrix Xav=
[x1av,x2av,x3av]T；
Step b, according to formula E (X)=Xav·UM, the average value matrix E (X) of calculating observation signal matrix X, wherein, UM
=[1,1 ..., 1] 1 M dimension row vectors are all for element；
Step c, according to formulaThe centralization matrix of calculating observation signal matrix XRealize observation
The centralization of signal matrix X.
A kind of above-mentioned wire selection method for power distribution network single phase earthing failure, it is characterised in that：Microcontroller described in step 403
Pass throughTo centralization matrixWhitening processing is carried out, wherein, D isCovariance matrix characteristic value, E is
Eigenvectors matrix.
The present invention has advantages below compared with prior art：
1st, method of the present invention step is simple, reasonable in design, realizes that convenient and input cost is low, easy to operate.
2nd, the present invention extracts the non-power frequency of zero-sequence current point by using all good improvement FastICA of convergence and stability
Amount, meanwhile, failure line selection is carried out by the route selection criterion for building Romanovsky, can self adaptation complex fault state and different nets
Network structure, reliable and stable, physical significance is apparent.
3rd, the present invention is by constructing the observation signal matrix of branch line zero-sequence current, and carries out center to the observation signal matrix
Change and the successive ignition mixed matrix of acquisition solution is carried out after whitening pretreatment, by calculating the hybrid matrix of branch line, extract hybrid matrix
The corresponding element of non-power frequency component in first row element, due to power frequency and non-work in the isolated source signal of branch line zero-sequence current
Frequency component is put in order arbitrarily, and non-power frequency component and power frequency component are distinguished using frequency algorithm, obtains branch line zero-sequence current
Non- power frequency component amplitude, using effect is good, is easy to promote the use of.
4th, the present invention recognize fault branch using the general characteristic of non-power frequency component, with it is existing transient state component is carried out it is many
The method of frequency range analysis compares, it is not necessary to complicated spectrum analysis, is more easy to implement.
5th, the present invention is novel in design reasonable, and integration degree is high, can in time pass through alarm signal transmission fault information, response
Speed is fast, practical, is easy to promote the use of.
In sum, the present invention is novel in design rationally, and step is simple, can self adaptation complex fault state and heterogeneous networks knot
Structure, extracts the non-power frequency component amplitude of zero-sequence current of each branch line by the way of iteration convergence, by absolute value deviation with it is critical
The contrast of deviation carries out failure line selection, and route selection effect is good, and method is accurate, reliable, and physical significance is apparent, is easy to promote the use of.
Below by drawings and Examples, technical scheme is described in further detail.
Brief description of the drawings
Fig. 1 is the schematic block circuit diagram of the Single-phase Earth-fault Selection in Distribution Systems equipment that the present invention is used.
Fig. 2 is the method flow block diagram of wire selection method for power distribution network single phase earthing failure of the present invention.
Fig. 3 a are that overcompensation degree is that 8%, sample frequency is the zero-sequence current oscillogram of branch line L1 in the case of 5000Hz.
Fig. 3 b are that overcompensation degree is that 8%, sample frequency is the zero-sequence current oscillogram of branch line L2 in the case of 5000Hz.
Fig. 3 c are that overcompensation degree is that 8%, sample frequency is the zero-sequence current oscillogram of branch line L3 in the case of 5000Hz.
Fig. 3 d are that overcompensation degree is that 8%, sample frequency is the zero-sequence current oscillogram of branch line L4 in the case of 5000Hz.
Fig. 4 a are power frequency sinusoidal component oscillogram in Fig. 3 a.
Fig. 4 b are power frequency cosine component oscillogram in Fig. 3 a.
Fig. 4 c are non-power frequency component oscillogram in Fig. 3 a.
Fig. 5 a are power frequency sinusoidal component oscillogram in Fig. 3 b.
Fig. 5 b are power frequency cosine component oscillogram in Fig. 3 b.
Fig. 5 c are non-power frequency component oscillogram in Fig. 3 b.
Fig. 6 a are power frequency cosine component oscillogram in Fig. 3 c.
Fig. 6 b are non-power frequency component oscillogram in Fig. 3 c.
Fig. 6 c are power frequency sinusoidal component oscillogram in Fig. 3 c.
Fig. 7 a are power frequency sinusoidal component oscillogram in Fig. 3 d.
Fig. 7 b are non-power frequency component oscillogram in Fig. 3 d.
Fig. 7 c are power frequency cosine component oscillogram in Fig. 3 d.
Description of reference numerals:
1-1-line voltage progress of disease circuit；1-2-line voltage wave filter；
1-3-residual voltage progress of disease circuit；1-4-residual voltage wave filter；
2-1-branch line zero-sequence current progress of disease circuit；2-2-branch line zero sequence current filter；
3-analog-digital converter；4-data storage；5-key operation module；
6-microcontroller；7-ethernet communication module；
9-alarm module；10-liquid crystal display circuit module；
11-switching value output module.
Specific embodiment
As depicted in figs. 1 and 2, wire selection method for power distribution network single phase earthing failure of the invention, comprises the following steps：
The real-time acquisition of step one, fault-signal：Using line voltage progress of disease circuit 1-1 real-time detections line voltage and lead to
Cross line voltage wave filter 1-2 and be filtered denoising, using residual voltage progress of disease circuit 1-3 real-time detections residual voltage simultaneously
Denoising is filtered by residual voltage wave filter 1-4, using multiple branch line zero-sequence current progress of disease circuit 2-1 real-time detections
Each branch line zero-sequence current simultaneously by branch line zero sequence current filter 2-2 is filtered denoising respectively；
Step 2, the collection of fault-signal, storage and analyzing and processing：Analog-digital converter 3 under the control of microcontroller 6,
The zero sequence current signal of line voltage, residual voltage and a plurality of branch line after processing filtering and noise reduction in step one enters line period and adopts
Sample, and signal to being gathered in each sampling period export after analog-to-digital conversion to microcontroller 6, microcontroller 6 by its
The zero sequence current signal of the line voltage, residual voltage and a plurality of branch line of reception is stored in data storage 4, and signal is entered
Row analyzing and processing, obtains the virtual value U of the phase voltage of line voltageaWith the virtual value U of residual voltage0；
The judgement whether step 3, singlephase earth fault occur：Microcontroller 6 is analyzed and processed half cycle for obtaining
The virtual value U of interior multiple residual voltages0With the power network residual voltage threshold value U of settingOP=0.15UaCompare, work as U0≥Uop
When, it is judged as that singlephase earth fault occurs, perform step 4；Otherwise, as multiple power network residual voltage U0In have less than power network zero
Sequence voltage threshold value UopWhen, return to step two；
The extraction of step 4, the non-power frequency component of each branch line zero-sequence current：Microcontroller 6 is to each branch line zero sequence in step 2
The non-power frequency component of electric current is extracted, extraction process of the microcontroller 6 to the non-power frequency component of the zero-sequence current of any branch line
All same, obtains amplitude coefficient vectorWherein, N is branch line number and N >=2, ajIt is any
The amplitude of the non-power frequency component of the branch line zero-sequence current of line, 1≤j≤N；
Amplitude a of the microcontroller 6 to the non-power frequency component of the zero-sequence current of any branch linejDuring extraction, process is as follows：
The observation signal matrix X of step 401, construction branch line zero-sequence current：Microcontroller 6 is using latter cycle of failure
Branch line zero-sequence current i0Data configuration branch line zero-sequence current observation signal matrixWherein, M is the sampling number in a cycle T
And M >=1, TsIt is the sampling time interval of two neighboring sampled point,i0(qTs) it is q-th zero-sequence current of sampled point
Sampled value, sin (q ω Ts) for unit power frequency component sinusoidal virtual observation signal sin (ω t) q-th sample point from
Dissipate value, cos (q ω Ts) it is cosine virtual observation signal cos (ω t) of unit power frequency component in the discrete of q-th sample point
Value, q=1,2 ..., M；
As shown in Fig. 3 a to Fig. 3 d, in the present embodiment, cycle T is 0.02s, and sample frequency is 5000Hz, and one
Sampling number M in cycle T is 100, and choosing the 380V power system in mines system that branch line quantity is 4 has carried out singlephase earth fault
Route selection is tested, and carries out branch line zero-sequence current extraction to branch line L1, branch line L2, branch line L3 and branch line L4 respectively.
The centralization of step 402, observation signal matrix X：Microcontroller 6 is obtained to observation signal matrix X centralizations treatment
Centralization matrix
In the present embodiment, microcontroller 6 described in step 402 is to observation signal matrix X centralizations treatment, and process is as follows：
Step a, according to formulaObtain the average value X of observation signal matrix Xav=
[x1av,x2av,x3av]T；
Step b, according to formula E (X)=Xav·UM, the average value matrix E (X) of calculating observation signal matrix X, wherein, UM
=[1,1 ..., 1] 1 M dimension row vectors are all for element；
Step c, according to formulaThe centralization matrix of calculating observation signal matrix XRealize observation letter
The centralization of number matrix X.
Step 403, centralization matrixAlbefaction：Microcontroller 6 is to the centralization matrix in step 402At albefaction
Reason, obtains whitening matrix Z；
In the present embodiment, microcontroller 6 described in step 403 passes throughTo centralization matrixCarry out white
Change is processed, wherein, D isCovariance matrix characteristic value, E isEigenvectors matrix.
Step 404, iteration initialization：W (k) is initialized by microcontroller 6, even k=0 arbitrarily takes W (0) and meets | |
W(0)||2=1, W (k) is the kth time iteration of the mixed matrix W of solution, wherein, W is the mixed matrix of solution of n × n dimensions, k=0,1 ... ..., M,
N is observation signal matrix line number, and in the present embodiment, W is the mixed matrix of solution of 3 × 3-dimensional；
Step 405, basisCarry out
Iterative process, wherein, λ is nonlinear function and G (x)=tan (a for the damping factor and 0 ＜ λ ＜ 1, G of iteration1X), a1For non-
The variation coefficient and 1≤a of linear function G1≤ 2, β are constant, and E (Y) is the average of variable data Y；
It should be noted that damping factors and λ=1 × 10 of the λ for iteration4, β be constant and β=0.8,Iterative process for improved
The iterative process of FastICA algorithms, the zero-sequence current analysis to latter cycle of failure on each branch line, can obtain each branch line
Non- power frequency component, the sine term of power frequency component and cosine term, as shown in Fig. 4 a to Fig. 4 c, improved FastICA can accurately divide
From the power frequency component and non-power frequency composition of the zero-sequence current of branch line L1；Shown as shown in Figure 5 a to 5 c, improved FastICA can be accurate
The zero-sequence current for separating branch line L2 power frequency component and non-power frequency composition；As shown in Fig. 6 a to Fig. 6 c, improved FastICA can
Accurately separate the power frequency component and non-power frequency composition of the zero-sequence current of branch line L3；It is improved as shown in Fig. 7 a to Fig. 7 c
FastICA can accurately separate the power frequency component and non-power frequency composition of the zero-sequence current of branch line L4.
Step 406, according to formula W (k+1) ← W (k+1)/| | W (k+1) | |, to the mixed matrix W (k+ of solution in step 405
1) it is normalized；
Step 407, judge whether W (k+1) restrains and obtain the mixed matrix W of solution：Microcontroller 6 limits ε and sentences according to convergence error
Do not restrain, when | W (k+1)-W (k) | ＞ ε and iterations are less than M, W (k+1) is not converged, performs step 405；Otherwise, W=W is taken
(k+1) step 408, is performed；
The acquisition of step 408, the amplitude coefficient of the non-power frequency component of branch line zero-sequence current：First, according to formula A=W-1,
Calculate the hybrid matrix A of branch line；Then, the corresponding element a of non-power frequency component in the first row element is extracted in hybrid matrix A1i, obtain
To the amplitude a of the non-power frequency component of branch line zero-sequence currentj=| a1i|, i=1,2 ..., n；
It should be noted that when j takes 1, a1The 1st article of amplitude of the non-power frequency component of the zero-sequence current of branch line is represented, it is micro-
Controller 6 is by the corresponding element of non-power frequency component in the first row element in the 1st article of hybrid matrix A of branch line | a1i| it is assigned to a1；Work as j
When taking 2, a2Represent the 2nd article of amplitude of the non-power frequency component of the zero-sequence current of branch line, microcontroller 6 is by the 2nd article of mixing of branch line
The corresponding element of non-power frequency component in first row element in matrix A | a1i| it is assigned to a2；By that analogy, amplitude coefficient vector is obtained
In the present embodiment, by the branch line zero-sequence current isolated X=AS of X in step 408, wherein, S is source signal and S is n
The matrix of × M dimensions, n row vector distinguishes non-power frequency component and power frequency component using frequency algorithm in S, extracts hybrid matrix
The corresponding element a of non-power frequency component in first row element in A1i, process is as follows：
Step Ι, selection frequency calculate sampled point：Microcontroller 6 searches sampled point in half cycle that it is analyzed and processed
Sid、WithWherein, SidIt is the corresponding electricity of d-th discrete point in the i-th row vector in isolated source signal S
Flow valuve,It is and SidIntervalThe corresponding current value of discrete point of cycle,It is and SidIntervalCycle it is discrete
The corresponding current value of point, and 0≤d≤M；
Step Ι Ι, according to formulaMeter
Calculate
Step Ι Ι Ι, judge source signal S in the i-th row vector whether be non-power frequency component：When in step Ι ΙWhen, the f being calculated is non-power frequency component, now, determines row sequence number i in source signal S, then hybrid matrix A
In corresponding element a in the first row element1iIt is the corresponding amplitude size of non-power frequency component, completes the non-work of the branch line zero-sequence current
The acquisition of the amplitude of frequency component；Otherwise, step Ι V are performed；
Next row vector is used as the i-th row vector in source signal S, repeat step Ι to step Ι in step Ι V, selection source signal S
ΙΙ。
In the present embodiment, hybrid matrixS be the isolated source signals of branch line zero-sequence current X andS1、S2And S3For the non-power frequency components of branch line zero-sequence current X, power frequency component sine term, power frequency component cosine term it is any
Arrangement, and S1、S2And S3It is the row vector with the corresponding sampled value of M sampled point.
In the present embodiment, source signal S is the matrix with three every trades vector, when i takes 1, selects the 1st row in source signal S
The sampled point of vector, when in the 1st row vectorWhen, the f being calculated is non-power frequency component, now, determines source
Row sequence number 1 in signal S, then corresponding element a in the first row element in hybrid matrix A11For the corresponding amplitude of non-power frequency component is big
It is small, end loop；Otherwise, the 2nd row vector, i.e. i take 2 in selection source signal S, the sampling of the 2nd row vector in selection source signal S
Point, when in the 2nd row vectorWhen, the f being calculated is non-power frequency component, now, determines row in source signal S
Sequence number 2, then corresponding element a in the first row element in hybrid matrix A12It is the corresponding amplitude size of non-power frequency component, terminates to follow
Ring；Otherwise, the 3rd row vector, i.e. i take 3 in selection source signal S, the sampled point of the 3rd row vector in selection source signal S, when the 3rd row
In vectorWhen, the f being calculated is non-power frequency component, now, determines row sequence number 3 in source signal S, then mix
Corresponding element a in first row element in conjunction matrix A13It is the corresponding amplitude size of non-power frequency component.
As Fig. 4 a to Fig. 4 c are respectively more than the isolated power frequency component sine terms of branch line L1 zero-sequence currents X, power frequency component
String and non-power frequency component, wherein, the non-power frequency component of branch line L1 zero-sequence currents X appears in the 3rd row of source signal S, therefore,
Element a in the hybrid matrix A of branch line L113The non-power frequency component amplitude of correspondence；Fig. 5 a to Fig. 5 c are respectively branch line L2 zero-sequence currents X points
From the power frequency component sine term, power frequency component cosine term that obtain and non-power frequency component, wherein, branch line L2 zero-sequence currents X's is non-
Power frequency component appears in the 3rd row of source signal S, therefore, element a in the hybrid matrix A of branch line L213The non-power frequency component width of correspondence
Value；Fig. 6 a to Fig. 6 c are respectively the isolated power frequency component cosine terms of branch line L3 zero-sequence currents X, non-power frequency component and power frequency
Component sine term, wherein, the non-power frequency component of branch line L3 zero-sequence currents X appears in the 2nd row of source signal S, therefore, branch line L3's
Element a in hybrid matrix A12The non-power frequency component amplitude of correspondence；Branch line L4 zero-sequence currents X is respectively shown in Fig. 7 a to Fig. 7 c to separate
Power frequency component sine term, non-power frequency component and the power frequency component cosine term for arriving, wherein, the non-power frequency of branch line L4 zero-sequence currents X
Component appears in the 2nd row of source signal S, therefore, element a in the hybrid matrix A of branch line L412The non-power frequency component amplitude of correspondence.
In the present embodiment, the non-power frequency component composition amplitude coefficient of each branch line zero-sequence current that will be obtained in Fig. 4 a to Fig. 7 c
Vectorial a=[a1,a2,a3,a4], wherein, a1It is element a in the hybrid matrix A of branch line L113Then a1=0.0277, a2It is branch line L2
Hybrid matrix A in element a13Then a2=0.0052, a3It is element a in the hybrid matrix A of branch line L312Then a3=0.0051, a4For
Element a in the hybrid matrix A of branch line L412Then a4=0.0074, it is seen then that the non-power frequency component coefficient of faulty spur L1 is non-faulting
3 times of big, its coefficients for being significantly greater than non-faulting branch line of the non-power frequency component coefficient of branch line.
The selection of step 5, faulty line, process is as follows：
Step 501, calculating absolute deviationWherein, agFor the greatest member in amplitude coefficient vector a and It is not comprising agAverage value and
Step 502, calculate critical deviation s σ, wherein, s is t distribution inspection coefficients, σ be standard deviation andIn the present embodiment, s takes 3.747；
Step 503, selection faulty line：WhenWhen, there is earth fault in bus；Otherwise, branch line connects
Greatest member is in earth fault, and amplitude coefficient vector aCorresponding branch line is faulty line；
It should be noted that calculating absolute deviation by Romanovsky criterionsIn the present embodiment,Critical deviation s σ=0.0049, according to route selection criterion, should be fault of branch line, and non-power frequency component coefficient
Maximum branch line L1 is faulty spur.
Step 6, failure line selection result show, transmit and alarm：Microcontroller 6 is aobvious by liquid crystal display circuit module 10
Show failure line selection result and by ethernet communication module 7 to host computer transmission fault route selection object information, it is defeated by switching value
Go out the output trip command of module 11, the timely alarm faulty line of alarm module 9.
The present invention is directed to 380V power system in mines systems according to the method described above, different transition resistance R under the conditions of overcompensationgAnd
Different faults circuit (containing bus) carries out multiple route selection process, obtains table 1：
The 380V power system in mines system route selection result of the tests of table 1
As can be seen from Table 1, during bus-bar fault, each non-power frequency component coefficient of branch line (i.e. coefficient vector element) size difference
Less, and absolute deviation always be less than critical deviation；During fault of branch line, the non-power frequency component coefficient ratio non-faulting of faulty spur
Branch line it is obvious big, and absolute deviation is always greater than critical deviation；It can be seen that, improved FastICA and Romanovsky criterions
With reference to selection method can accurately distinguish fault of branch line and bus-bar fault, and critical deviation becomes with different malfunctions
Change, therefore route selection has self application.
When can be seen that different transition resistances, the condition of different faults branch line by the result of table 1, this method is unaffected,
Selection method is accurate and effective；There is not wrong choosing or leakage choosing, illustration method have complex fault state and heterogeneous networks structure from
Adaptability
The above, is only presently preferred embodiments of the present invention, and not the present invention is imposed any restrictions, every according to the present invention
Any simple modification, change and equivalent structure change that technical spirit is made to above example, still fall within skill of the present invention
In the protection domain of art scheme.
Claims (4)
1. a kind of wire selection method for power distribution network single phase earthing failure, it is characterised in that the method is comprised the following steps：
The real-time acquisition of step one, fault-signal：Using line voltage progress of disease circuit (1-1) real-time detection line voltage and pass through
Line voltage wave filter (1-2) is filtered denoising, using the residual voltage progress of disease circuit (1-3) real-time detection residual voltage
And denoising is filtered by residual voltage wave filter (1-4), it is real using multiple branch line zero-sequence current progress of disease circuits (2-1)
When detect each branch line zero-sequence current and denoising be filtered by branch line zero sequence current filter (2-2) respectively；
Step 2, the collection of fault-signal, storage and analyzing and processing：Analog-digital converter (3) under the control of microcontroller (6),
The zero sequence current signal of line voltage, residual voltage and a plurality of branch line after processing filtering and noise reduction in step one enters line period and adopts
Sample, and signal to being gathered in each sampling period export after analog-to-digital conversion giving microcontroller (6), microcontroller (6)
The zero sequence current signal storage of the line voltage, residual voltage and a plurality of branch line that are received is in data storage (4) and right
Signal is analyzed treatment, obtains the virtual value U of the phase voltage of line voltageaWith the virtual value U of residual voltage0；
The judgement whether step 3, singlephase earth fault occur：Microcontroller (6) is analyzed and processed in half cycle for obtaining
Multiple residual voltages virtual value U0With the power network residual voltage threshold value U of settingOP=0.15UaCompare, work as U0≥Uop
When, it is judged as that singlephase earth fault occurs, perform step 4；Otherwise, as multiple power network residual voltage U0In have less than power network zero
Sequence voltage threshold value UopWhen, return to step two；
The extraction of step 4, the non-power frequency component of each branch line zero-sequence current：Microcontroller (6) is to each branch line zero sequence electricity in step 2
The non-power frequency component of stream is extracted, extraction process of the microcontroller (6) to the non-power frequency component of the zero-sequence current of any branch line
All same, obtains amplitude coefficient vectorWherein, N is branch line number and N >=2, ajIt is any
The amplitude of the non-power frequency component of the branch line zero-sequence current of line, 1≤j≤N；
The amplitude a of the non-power frequency component of zero-sequence current of the microcontroller (6) to any branch linejDuring extraction, process is as follows：
The observation signal matrix X of step 401, construction branch line zero-sequence current：Microcontroller (6) utilizes latter branch of cycle of failure
Line zero-sequence current i0Data configuration branch line zero-sequence current observation signal matrixWherein, M is the sampling number in a cycle T
And M >=1, TsIt is the sampling time interval of two neighboring sampled point,i0(qTs) it is q-th zero-sequence current of sampled point
Sampled value, sin (q ω Ts) for unit power frequency component sinusoidal virtual observation signal sin (ω t) q-th sample point from
Dissipate value, cos (q ω Ts) it is cosine virtual observation signal cos (ω t) of unit power frequency component in the discrete of q-th sample point
Value, q=1,2 ..., M；
The centralization of step 402, observation signal matrix X：Microcontroller (6) is processed observation signal matrix X centralizations, in obtaining
Heart matrix
Step 403, centralization matrixAlbefaction：Microcontroller (6) is to the centralization matrix in step 402Whitening processing,
Obtain whitening matrix Z；
Step 404, iteration initialization：W (k) is initialized by microcontroller (6), even k=0 arbitrarily takes W (0) and meets | | W
(0)||2=1, W (k) is the kth time iteration of the mixed matrix W of solution, wherein, W is the mixed matrix of solution of n × n dimensions, k=0,1 ... ..., M, n
It is observation signal matrix line number；
Step 405, basisIt is iterated
Process, wherein, λ is nonlinear function and G (x)=tan (a for the damping factor and 0 ＜ λ ＜ 1, G of iteration1X), a1For non-linear
The variation coefficient and 1≤a of function G1≤ 2, β are constant, and E (Y) is the average of variable data Y；
Step 406, according to formula W (k+1) ← W (k+1)/| | W (k+1) | |, the mixed matrix W (k+1) of solution in step 405 is carried out
Normalized；
Step 407, judge whether W (k+1) restrains and obtain the mixed matrix W of solution：Microcontroller (6) limits ε and differentiates according to convergence error
Convergence, when | W (k+1)-W (k) | ＞ ε and iterations are less than M, W (k+1) is not converged, performs step 405；Otherwise, W=W (k are taken
+ 1) step 408, is performed；
The acquisition of step 408, the amplitude coefficient of the non-power frequency component of branch line zero-sequence current：First, according to formula A=W-1, calculate
The hybrid matrix A of branch line；Then, the corresponding element a of non-power frequency component in the first row element is extracted in hybrid matrix A1i, propped up
The amplitude a of the non-power frequency component of line zero-sequence currentj=| a1i|, i=1,2 ..., n；
The selection of step 5, faulty line, process is as follows：
Step 501, calculating absolute deviationWherein, agFor the greatest member in amplitude coefficient vector a and It is not comprising agAverage value and
Step 502, calculate critical deviation s σ, wherein, s is t distribution inspection coefficients, σ be standard deviation and
Step 503, selection faulty line：WhenWhen, there is earth fault in bus；Otherwise, there is ground connection event in branch line
Barrier, and greatest member is in amplitude coefficient vector aCorresponding branch line is faulty line；
Step 6, failure line selection result show, transmit and alarm：Microcontroller (6) is aobvious by liquid crystal display circuit module (10)
Show failure line selection result and by ethernet communication module (7) to host computer transmission fault route selection object information, by switching value
Output module (11) exports trip command, the timely alarm faulty line of alarm module (9).
2. according to a kind of wire selection method for power distribution network single phase earthing failure described in claim 1, it is characterised in that：In step 408
By the branch line zero-sequence current isolated X=AS of X, wherein, S is the matrix that source signal and S are tieed up for n × M, and n row vector is used in S
Frequency algorithm distinguishes non-power frequency component and power frequency component, non-power frequency component pair in the first row element in extraction hybrid matrix A
The element a for answering1i, process is as follows：
Step Ι, selection frequency calculate sampled point：Microcontroller (6) searches sampled point S in half cycle that it is analyzed and processedid、WithWherein, SidIt is the corresponding current value of d-th discrete point in the i-th row vector in isolated source signal S,It is and SidIntervalThe corresponding current value of discrete point of cycle,It is and SidIntervalThe discrete point correspondence of cycle
Current value, and 0≤d≤M；
Step Ι Ι, according to formulaCalculate
Step Ι Ι Ι, judge source signal S in the i-th row vector whether be non-power frequency component：When in step Ι ΙWhen,
The f being calculated is non-power frequency component, now, determines row sequence number i in source signal S, then phase in the first row element in hybrid matrix A
The element a for answering1iIt is the corresponding amplitude size of non-power frequency component, the amplitude for completing the non-power frequency component of the branch line zero-sequence current is obtained
Take；Otherwise, step Ι V are performed；
Next row vector is used as the i-th row vector in source signal S, repeat step Ι to step Ι Ι Ι in step Ι V, selection source signal S.
3. according to a kind of wire selection method for power distribution network single phase earthing failure described in claim 1 or 2, it is characterised in that：Step 402
Described in microcontroller (6) to observation signal matrix X centralizations treatment, process is as follows：
Step a, according to formulaObtain the average value X of observation signal matrix Xav=[x1av,
x2av,x3av]T；
Step b, according to formula E (X)=Xav·UM, the average value matrix E (X) of calculating observation signal matrix X, wherein, UM=[1,
1 ..., 1] 1 M dimension row vectors are all for element；
Step c, according to formulaThe centralization matrix of calculating observation signal matrix XRealize observation signal square
The centralization of battle array X.
4. according to a kind of wire selection method for power distribution network single phase earthing failure described in claim 3, it is characterised in that：In step 403
The microcontroller (6) passes throughTo centralization matrixWhitening processing is carried out, wherein, D isCovariance square
The characteristic value of battle array, E isEigenvectors matrix.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610834659.6A CN106199342B (en) | 2016-09-20 | 2016-09-20 | A kind of wire selection method for power distribution network single phase earthing failure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610834659.6A CN106199342B (en) | 2016-09-20 | 2016-09-20 | A kind of wire selection method for power distribution network single phase earthing failure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106199342A CN106199342A (en) | 2016-12-07 |
| CN106199342B true CN106199342B (en) | 2017-05-31 |
Family
ID=58068086
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610834659.6A Active CN106199342B (en) | 2016-09-20 | 2016-09-20 | A kind of wire selection method for power distribution network single phase earthing failure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106199342B (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3571514A4 (en) * | 2017-01-18 | 2020-11-04 | HRL Laboratories, LLC | Cognitive signal processor for simultaneous denoising and blind source separation |
| CN108008234A (en) * | 2017-11-10 | 2018-05-08 | 安徽徽远成电气科技股份有限公司 | Single-phase earthing defends managing device |
| CN109507532A (en) * | 2018-11-22 | 2019-03-22 | 西安科技大学 | A kind of small current neutral grounding system Feeder Section Location |
| CN109375041B (en) * | 2018-12-24 | 2021-01-05 | 华北科技学院 | Single-phase grounding fault judgment method for small-current grounding system |
| US11169187B2 (en) * | 2019-06-28 | 2021-11-09 | King Fahd University Of Petroleum And Minerals | Zig zag based load flow method and system for extended radial distribution systems |
| CN110412427A (en) * | 2019-08-21 | 2019-11-05 | 成都信息工程大学 | A kind of low-voltage power fault detection positioning system and fault detection method |
| CN110568313B (en) * | 2019-09-11 | 2022-01-18 | 荆平 | Single-phase earth fault positioning method and system for small current earthing system |
| CN112485713B (en) * | 2020-11-30 | 2022-08-16 | 云南电网有限责任公司电力科学研究院 | Line selection device and method based on zero-break characteristic of ground fault current |
| CN113820566B (en) * | 2021-10-10 | 2023-05-09 | 西安科技大学 | Leakage selecting method for coal mine power grid |
| CN114034987A (en) * | 2021-11-23 | 2022-02-11 | 东莞电力设计院有限公司 | Single-phase earth fault detection method based on zero-sequence component volatility |
| CN114755532A (en) * | 2022-04-26 | 2022-07-15 | 国网四川省电力公司营销服务中心 | Single-phase earth fault identification method and system based on electric energy multidimensional information fusion |
| CN115589237B (en) * | 2022-12-13 | 2023-03-17 | 青岛鼎信通讯股份有限公司 | High-frequency current signal branch attribution judging method suitable for electric power field |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100883777B1 (en) * | 2007-01-26 | 2009-02-18 | 명지대학교 산학협력단 | Method for Disorder Display of Terminal Unit in Power Distribution Automation System |
| CN103743949A (en) * | 2014-01-06 | 2014-04-23 | 国家电网公司 | Detection method of harmonic and inter-harmonic based on single-channel FastICA (Fast Independent Component Analysis) |
| CN105785229B (en) * | 2016-05-05 | 2017-11-17 | 国网天津市电力公司 | The Fault Identification method of isolated neutral system |
-
2016
- 2016-09-20 CN CN201610834659.6A patent/CN106199342B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN106199342A (en) | 2016-12-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106199342B (en) | A kind of wire selection method for power distribution network single phase earthing failure | |
| CN108254657B (en) | Power distribution network section with low-current ground faults localization method based on Study of Transient Energy | |
| CN107064734A (en) | A kind of flexible direct current Fault Location for Distribution Network method of utilization fault transient process | |
| CN105067948B (en) | A kind of Small Electric Current Earthing And Routing Device and single phase earth fault detection method | |
| Sanaye-Pasand et al. | Transmission line fault detection & phase selection using ANN | |
| Saravanababu et al. | Transmission line faults detection, classification, and location using discrete wavelet transform | |
| CN105974264B (en) | A kind of fault-line selecting method based on phase current transient characteristic | |
| CN202676854U (en) | Fuzzy comprehensive decision power distribution network single-phase earth fault line selection system | |
| CN108469576A (en) | A kind of multiterminal alternating current-direct current mixing power distribution network DC Line Fault detection method | |
| CN104466922B (en) | A kind of quick bus bar protecting method of current polarity comparison expression | |
| CN107179466A (en) | The fault line selection method for single-phase-to-ground fault of small current neutral grounding system | |
| CN105790239A (en) | High-voltage direct-current power transmission line non-unit protection method based on S transformation | |
| CN109217267A (en) | Multiterminal flexible direct current power grid longitudinal protection method and system based on current-limiting inductance polarity of voltage | |
| CN111413643A (en) | Power distribution network single-phase earth fault identification method | |
| CN104237703A (en) | Method for recognizing properties of three-phase adaptive re-closing faults of lines with parallel reactors | |
| CN103439624B (en) | Supertension line fault phase selection method based on voltage fault component | |
| CN107677904A (en) | A kind of voltage dip origin cause of formation discrimination method and system | |
| CN105914718B (en) | A kind of earth-fault protection method based on difference of phase currents | |
| Zaki et al. | An investigated reactive power measurements-based fault-identification scheme for teed transmission lines | |
| CN105021954A (en) | Bus protection method based on line-mode current S-transformation argument detection | |
| Jimenez-Aparicio et al. | Fast traveling wave detection and identification method for power distribution systems using the discrete wavelet transform | |
| CN107085168A (en) | A kind of single-phase earth fault line selection device containing many times cable outlets | |
| CN112485595A (en) | Power distribution network ground fault line selection protection method and device | |
| CN107703415B (en) | Two-level three-phase four-wire system D-STATCOM main loop switching device open circuit fault positioning method | |
| CN102082420A (en) | Longitudinal differential protection method of power transmission line |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |