CN108562821A - A kind of method and system determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax - Google Patents

A kind of method and system determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax Download PDF

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CN108562821A
CN108562821A CN201810432276.5A CN201810432276A CN108562821A CN 108562821 A CN108562821 A CN 108562821A CN 201810432276 A CN201810432276 A CN 201810432276A CN 108562821 A CN108562821 A CN 108562821A
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fault
data
regression models
optimized parameter
failure
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CN108562821B (en
Inventor
李辉
陈江波
陈浩然
戴敏
陈维江
吕军
宁昕
田野
陈金猛
方茂欢
蒋元宇
邱进
马硕
翟文鹏
蔡胜伟
郭慧浩
邵苠峰
尹晶
费烨
何妍
陈程
杜砚
程婷
王华云
郑蜀江
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STATE GRID JIANGXI ELECTRIC POWER Co
China Electric Power Research Institute Co Ltd CEPRI
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STATE GRID JIANGXI ELECTRIC POWER Co
China Electric Power Research Institute Co Ltd CEPRI
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08Locating faults in cables, transmission lines, or networks
    • G01R31/081Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/086Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08Locating faults in cables, transmission lines, or networks
    • G01R31/088Aspects of digital computing

Abstract

The invention discloses a kind of method and system determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax, including:Obtain the fault data for each presetting node in power distribution network in multiple default nodes of circuit;The fault data is handled, obtains fault signature data, and establish failure identification and fault signature database;Data in the failure identification and fault signature database are divided into training set and test set according to fault type, and carry out route selection using Softmax regression models and training set according to default iterations and recognize the determining optimized parameter of training, to determine the corresponding Softmax regression models of optimized parameter;Fault type and position are predicted according to the real time fail data of power grid using the corresponding Softmax regression models of the optimized parameter, to determine power distribution network one-way earth fault route selection.Maintenance data of the present invention is trained and verifies to Softmax regression models, improves data-handling capacity and route selection accuracy, promotes the research and development and application of new distribution terminal.

Description

It is a kind of based on Softmax determine Single-phase Earth-fault Selection in Distribution Systems method and System
Technical field
The present invention relates to power distribution network risk analysis and control technology fields, and are based on more particularly, to one kind Softmax determines the method and system of Single-phase Earth-fault Selection in Distribution Systems.
Background technology
Small current neutral grounding problem is global problem, and the difficult point that fault identification is primarily present is at present:First, small Electric current single-phase earthing, fault current are small, it is difficult to detect;Second is that system structure is complicated, neutral grounding mode is different, abort situation Difference, fault type is different, and caused fault signature is also different, and the threshold value of detection is difficult to adjust;Third, fault characteristic signals Pass through catadioptric, mutual superimposed interference, it is not easy to isolate significant characteristic quantity in network.
Meanwhile, there are following three points in the main reason for poor for existing methods validity:(1) without specific fault data Analysis, only adjusts short circuit current, and small current neutral grounding current value is smaller, and simple limiting short-circuit current is difficult to be carried out to small current neutral grounding Judge;(2) be based only on a certain characteristic signal and carry out route selection, due to different small current grounding faults because of neutral grounding mode not Different with, ground resistance and diversification is presented, single features signal can not describe all types of fault signatures, therefore based on one kind The method validity that characteristic signal carries out route selection is just limited to;(3) since practical distribution network can not largely carry out ground connection event Barrier simulation, therefore the mode of the selection method generally use dynamic simulation based on multi signal data characteristics amount carries out, but Digital Simulation The case where modeling can not accurately simulate true distribution net equipment completely, can ignore the influence factors such as transient characterisitics, simultaneously because imitative The limitation of true step-length, has certain limitations the transient signal frequency range of offer, proposed method is caused to be answered in systems in practice It is limited with effect.
Softmax regression algorithms are that a kind of typical more classification problem regression algorithms are widely used in machine before this Learning areas among more classification purposes such as animals and plants classification, also has for Handwritten Digit Recognition and carries out hydraulic pump using the algorithm Fault diagnosis application example.But Softmax regression algorithms have no application in field of power.In field of power, In recent years Chinese each province configures a large amount of recording type fault detector, a large amount of true distribution network failure data of acquisition, while but It is insufficient to the processing analysis ability of data.
If currently, wanting to propose the single-phase grounding selecting strategy based on authentic and valid data, need to solve the problems, such as following: First, obtaining the Wave data under effective failure generating state, which will occur position with the type of failure with failure, Location information is circuit number in route selection strategy, while the sample rate of enrolled data waveform wants sufficiently high, including number of faults According to feature;It second is that the data waveform of admission cannot be used directly for fault identification, need to be pre-processed, be isolated and failure with reaching The characteristic quantity of data characteristics strong correlation once carries out fault identification;Third, to propose the application process of fault signature, ordinary circumstance Under, fault signature and fault location information and nonlinear correspondence relation will classify by regression algorithm, to reach effective choosing Select the purpose of faulty line.
Therefore, because any of the above shortcomings and deficiencies make full use of true power distribution network to propose more effective route selection strategy In fault data, a kind of wire selection method for power distribution network single phase earthing failure is needed, to solve accurately determine and break down Route the problem of.
Invention content
The present invention proposes a kind of method and system determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax, with solution The problem of certainly can not accurately determining the route to break down.
To solve the above-mentioned problems, according to an aspect of the invention, there is provided one kind determining power distribution network based on Softmax The method of single-phase earth fault line selection, which is characterized in that the method includes:
Step 1, the fault data for each presetting node in power distribution network in multiple default nodes of circuit is obtained, wherein described Fault data includes:Three-phase voltage data, three-phase current data, the phase data of voltage, the phase information of electric current and failure The absolute time information of generation;
Step 2, the fault data is handled, obtain fault signature data, and according to the fault signature data, Fault type and abort situation mark establish failure identification and fault signature database, wherein the fault signature data include more A characteristic quantity;
Step 3, by the data in the failure identification and fault signature database according to fault type be divided into training set and Test set, and carry out route selection identification using Softmax regression models and training set according to default iterations and train determination optimal Parameter, to determine the corresponding Softmax regression models of optimized parameter;
Step 4, using the corresponding Softmax regression models of the optimized parameter according to the real time fail data pair event of power grid Barrier type and position are predicted, to determine power distribution network one-way earth fault route selection.
Preferably, wherein acquiring the fault data at each default node using recording type fault detector.
Preferably, wherein described handle the fault data, fault signature data are obtained, including:
The fault data is handled, synthesis obtains failure volume, wherein the failure volume includes:Frequency Variable quantity, the variable quantity of voltage, the change rate of frequency, the change rate of voltage, the change rate of electric current, phase angle change rate, have The change rate of power, the change rate of inactivity, frequency is distorted with change rate, the current harmonics of power, voltage harmonic is distorted, power The each harmonic component of factor and voltage and current;
The failure volume is handled according to rough set theory, the low failure volume of the degree of correlation is got rid of, obtains Take fault signature data.
Preferably, wherein the default iterations of the basis carry out route selection using Softmax regression models and training set and distinguish Know training and determines optimized parameter, to determine the corresponding Softmax regression models of optimized parameter, including:
Determine that the cost function of Softmax regression algorithms, cost function are:
Wherein, the sample of Softmax regression models comes from k class, shares m, then the training set being made of these samples For { (x(1),y(1)),(x(2),y(2)),…,(x(m),y(m)), whereinLabel:y(t)∈ { 1,2 ..., k }, for Given input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each point of x The probability that class result occurs;
Route selection identification training is carried out using gradient descent method to the cost function according to default iterations, is determined optimal Parameter obtains the corresponding Softmax regression models of optimized parameter.
Preferably, wherein the method further includes:
The fault signature data of sample in test set are corresponded to using the optimized parameter corresponding Softmax regression models Fault type and abort situation predicted;
Prediction accuracy is calculated, and judges whether prediction accuracy is more than or equal to default accuracy threshold value;Wherein,
If prediction accuracy is more than or equal to default accuracy threshold value, directly utilizes and have determined that optimized parameter is corresponding Softmax regression models determine Single-phase Earth-fault Selection in Distribution Systems;
If prediction accuracy is less than default accuracy threshold value, increase iterations according to iteration step length is preset, and return Step 3 carries out route selection using Softmax regression models and training set and recognizes the determining optimized parameter of training, to determine optimized parameter pair The Softmax regression models answered.
According to another aspect of the present invention, it provides one kind and determining that one-phase earthing failure in electric distribution network selects based on Softmax The system of line, which is characterized in that the system comprises:
Fault data acquiring unit, for obtaining the event for each presetting node in power distribution network in multiple default nodes of circuit Hinder data, wherein the fault data includes:Three-phase voltage data, three-phase current data, the phase data of voltage, the phase of electric current The absolute time information that position information and failure occur;
Database unit obtains fault signature data, and according to described for handling the fault data Fault signature data, fault type and abort situation mark establish failure identification and fault signature database, wherein the failure Characteristic includes multiple characteristic quantities;
Model determination unit, for dividing the data in the failure identification and fault signature database according to fault type For training set and test set, and Softmax regression models and training set is utilized to carry out route selection identification instruction according to default iterations Practice and determine optimized parameter, to determine the corresponding Softmax regression models of optimized parameter;
Failure line selection determination unit is used for the corresponding Softmax regression models of the optimized parameter according to the reality of power grid When fault data fault type and position are predicted, to determine power distribution network one-way earth fault route selection.
Preferably, wherein acquiring the fault data at each default node using recording type fault detector.
Preferably, wherein the fault data acquiring unit, handles the fault data, fault signature number is obtained According to, including:
The fault data is handled, synthesis obtains failure volume, wherein the failure volume includes:Frequency Variable quantity, the variable quantity of voltage, the change rate of frequency, the change rate of voltage, the change rate of electric current, phase angle change rate, have The change rate of power, the change rate of inactivity, frequency is distorted with change rate, the current harmonics of power, voltage harmonic is distorted, power The each harmonic component of factor and voltage and current;
The failure volume is handled according to rough set theory, the low failure volume of the degree of correlation is got rid of, obtains Take fault signature data.
Preferably, wherein the model determination unit, Softmax regression models and training are utilized according to default iterations Collection carries out route selection identification training and determines optimized parameter, to determine the corresponding Softmax regression models of optimized parameter, including:
Determine that the cost function of Softmax regression algorithms, cost function are:
Wherein, the sample of Softmax regression models comes from k class, shares m, then the training set being made of these samples For { (x(1),y(1)),(x(2),y(2)),…,(x(m),y(m)), whereinLabel:y(t)∈ { 1,2 ..., k }, for giving Fixed input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each classification of x As a result the probability occurred;
Route selection identification training is carried out using gradient descent method to the cost function according to default iterations, is determined optimal Parameter obtains the corresponding Softmax regression models of optimized parameter.
Preferably, wherein the system also includes:Accuracy validation unit,
For the fault signature data using the corresponding Softmax regression models of the optimized parameter to sample in test set Corresponding fault type and abort situation are predicted;
For calculating prediction accuracy, and judge whether prediction accuracy is more than or equal to default accuracy threshold value;Wherein,
If prediction accuracy is more than or equal to default accuracy threshold value, directly utilizes and have determined that optimized parameter is corresponding Softmax regression models determine Single-phase Earth-fault Selection in Distribution Systems;
If prediction accuracy is less than default accuracy threshold value, increase iterations according to iteration step length is preset, and return Model determination unit carries out route selection using Softmax regression models and training set and recognizes the determining optimized parameter of training, to determine most The corresponding Softmax regression models of excellent parameter.
The present invention provides a kind of method and system determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax, obtain Take the fault data of circuit in power distribution network;The fault data is handled, fault signature data are obtained and establishes failure mark Know and fault signature database;Data in the failure identification and fault signature database are divided into training according to fault type Collection and test set, and carry out route selection using Softmax regression models and training set according to default iterations and recognize training determination The corresponding Softmax regression models of optimized parameter;Finally, using the corresponding Softmax regression models of the optimized parameter according to The real time fail data of power grid predict fault type and position, to determine power distribution network one-way earth fault circuit.This hair It is bright to utilize truthful data, by processing extraction to data and the relevant characteristic quantity of abort situation, Softmax regression models are drawn Enter single-phase earthing data identification field, maintenance data is trained and verifies to Softmax regression models, has hewed out with item event Barrier identification new route, improves data-handling capacity and route selection accuracy, set for new distribution terminal protection algorithm, threshold value, The verification of action logic strategy provides new approaches, promotes the research and development and application of new distribution terminal.
Description of the drawings
By reference to the following drawings, exemplary embodiments of the present invention can be more fully understood by:
Fig. 1 is the method for determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax according to embodiment of the present invention 100 flow chart;
Fig. 2 is the rough set model figure according to embodiment of the present invention;
Fig. 3 is the power distribution network typical overhead gauze frame structure chart according to embodiment of the present invention;
Fig. 4 is 500 obtained data separating point diagrams of iteration according to embodiment of the present invention;
Fig. 5 is 1000 obtained data separating point diagrams of iteration according to embodiment of the present invention;And
Fig. 6 is to be based on what Softmax determined Single-phase Earth-fault Selection in Distribution Systems according to the school of embodiment of the present invention The structural schematic diagram of system 600.
Specific implementation mode
Exemplary embodiments of the present invention are introduced referring now to the drawings, however, the present invention can use many different shapes Formula is implemented, and is not limited to the embodiment described herein, and to provide these embodiments be to disclose at large and fully The present invention, and fully convey the scope of the present invention to person of ordinary skill in the field.Show for what is be illustrated in the accompanying drawings Term in example property embodiment is not limitation of the invention.In the accompanying drawings, identical cells/elements use identical attached Icon is remembered.
Unless otherwise indicated, term (including scientific and technical terminology) used herein has person of ordinary skill in the field It is common to understand meaning.Further it will be understood that with the term that usually used dictionary limits, should be understood as and its The context of related field has consistent meaning, and is not construed as Utopian or too formal meaning.
Fig. 1 is the method for determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax according to embodiment of the present invention 100 flow chart.As shown in Figure 1, embodiments of the present invention offer determines one-phase earthing failure in electric distribution network based on Softmax The method of route selection utilizes truthful data, and by processing extraction to data and the relevant characteristic quantity of abort situation, Softmax is returned Model is returned to introduce single-phase earthing data identification field, maintenance data is trained and verifies to Softmax regression models, hews out With a fault identification new route, data-handling capacity and route selection accuracy are improved, is new distribution terminal protection algorithm, threshold Value setting, the verification of action logic strategy provide new approaches, promote the research and development and application of new distribution terminal.The reality of the present invention What the mode of applying provided determines the method 100 of Single-phase Earth-fault Selection in Distribution Systems since step 101 place based on Softmax, Step 101 obtains the fault data for each presetting node in power distribution network in multiple default nodes of circuit, wherein the number of faults According to including:What three-phase voltage data, three-phase current data, the phase data of voltage, the phase information of electric current and failure occurred Absolute time information.
Preferably, wherein acquiring the fault data at each default node using recording type fault detector.
Preferably, in step 102, the fault data is handled, obtains fault signature data, and according to the event Barrier characteristic, fault type and abort situation mark establish failure identification and fault signature database, wherein the failure is special It includes multiple characteristic quantities to levy data.
Preferably, wherein described handle the fault data, fault signature data are obtained, including:To the event Barrier data are handled, and synthesis obtains failure volume, wherein the failure volume includes:The variable quantity of frequency, voltage Variable quantity, the change rate of frequency, the change rate of voltage, the change rate of electric current, the change rate of phase angle, the change rate for having power, nothing The change rate of power, frequency be distorted with change rate, the current harmonics of power, voltage harmonic distortion, power factor and voltage and The each harmonic component of electric current;
The failure volume is handled according to rough set theory, the low failure volume of the degree of correlation is got rid of, obtains Take fault signature data.
In embodiments of the present invention, the fault data of record is handled, the variation delta f of frequency synthesisi, electricity The variation delta V of pressurei, change rate (the Δ f/ Δs t) of frequencyi, change rate (the Δ V/ Δs t) of voltagei, change rate (the Δ I/ of electric current Δt)i, the change rate of phase angleThere is change rate (the Δ P/ Δs t) of poweri, change rate (the Δ Q/ Δs t) of inactivityi, Frequency with power change rate (Δ f/ Δ P)i, current harmonics distortion CTHD, voltage harmonic distortion VTHD, power factorWith And the quantity of states such as each harmonic component of voltage and current.Then, the low quantity of state of the degree of correlation is got rid of according to rough set theory, remained Remaining quantity of state, that is, fault signature data.
In embodiments of the present invention, ifX is fault message, and U is fault signature set.RBIt is one of U Equivalence relation is judged based on existing knowledge, i.e. known fault location information, U/B={ E1,E2,…,EeIndicate The degree of correspondence of each fault message and abort situation.X is about RBLower aprons collection, upper approximate set is defined respectively as:
Wherein, upper approximate set representations are according to existing knowledge RB, judge the object composition that centainly belongs to or may belong to X in U Set, lower aprons set representations are according to existing knowledge RB, judge the set for the object composition for belonging to X in U certainly.
Obviously,The lower and upper approximations of X say that domain U is divided into three disjoint regions, I.e. positive domain POSRB(X), Boundary Region BNDRB(X) and negative domain NEGRB(X), wherein
POSRB(X)=RB (X),
Fig. 2 is the rough set model figure according to embodiment of the present invention.As shown in Fig. 2, intuitively show the positive domain of X, Boundary Region and negative domain, the characteristic for falling into positive domain is high with the abort situation degree of correlation, and Boundary Region has shown Partial Feature data It is relevant with abort situation, the characteristic in negative domain is completely uncorrelated to abort situation.It is event with remaining quantity of state Hinder characteristic, is combined with fault type and fault location information, establish failure identification and fault signature database.And it will be different The failure of type is divided into two groups, and one group is trained for fault identification algorithm, another group of validity for being used for verification algorithm.
Preferably, in step 103, by the data in the failure identification and fault signature database according to fault type point For training set and test set, and Softmax regression models and training set is utilized to carry out route selection identification instruction according to default iterations Practice and determine optimized parameter, to determine the corresponding Softmax regression models of optimized parameter.
Preferably, wherein the default iterations of the basis carry out route selection using Softmax regression models and training set and distinguish Know training and determines optimized parameter, to determine the corresponding Softmax regression models of optimized parameter, including:
Determine that the cost function of Softmax regression algorithms, cost function are:
Wherein, the sample of Softmax regression models comes from k class, shares m, then the training set being made of these samples For { (x(1),y(1)),(x(2),y(2)),…,(x(m),y(m)), whereinLabel:y(t)∈ { 1,2 ..., k }, for giving Fixed input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each classification of x As a result the probability occurred;
Route selection identification training is carried out using gradient descent method to the cost function according to default iterations, is determined optimal Parameter obtains the corresponding Softmax regression models of optimized parameter.
In embodiments of the present invention, the corresponding Softmax regression models of optimized parameter are determined, including:
Assuming that the sample of Softmax regression models comes from k class, m are shared, then the training set being made of these samples is {(x(1),y(1)),(x(2),y(2)),…,(x(m),y(m))}.WhereinLabel:y(t)∈{1,2,…,k}.For giving Fixed input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each classification of x As a result the probability occurred, thus, it is supposed that function will export a k dimensional vector (vector element and be 1) to indicate that this k is estimated Probability.Assuming that function hθ(x) form is as follows:
WhereinIt is model parameter, a θ is assigned to each characteristic quantity, to characterize this feature Ability of the amount for failure judgement position.p(y(i)=j | x(i);θj) indicate sample x(i)Belong to the probability of jth class. It is normalization probability distribution and the sum of to make all probability be 1.In order to facilitate expression, an indicative letter is expressed as using 1 { } Number, i.e., 1 { true }=1,1 { false }=0.So, the cost function of Softmax regression algorithms may be defined as:
Softmax functions are added up k possible classifications, i.e., x are classified as classification J in Softmax recurrence Probability be:
Classification wherein corresponding to maximum probability is the class categories of x.
In practical applications, weight decaying is added usually in above-mentioned cost function to solve the parameter of Softmax recurrence Numerical problem caused by redundancy, then cost function become:
There are this weight attenuation term, cost function to reform into stringent convex function, guarantees to obtain unique solution, have Effect solves parameter redundancy issue.
Partial derivative is asked to J (θ):
The renewal process of θ can be obtained according to gradient descent method:
Wherein, α is Learning Step, therefore can be obtained:
Go out to approach the θ of optimal solution by gradient descent method iteration, then all θ values generation is returned to and assumes function hθ(x) it in, asks The probability for taking all station location markers of numerous characteristic quantity set expression under event of failure, obtains trained Softmax and returns mould Type.
Preferably, in step 104, using the corresponding Softmax regression models of the optimized parameter according to the real-time of power grid Fault data predicts fault type and position, to determine power distribution network one-way earth fault route selection.
Preferably, wherein the method further includes:
The fault signature data of sample in test set are corresponded to using the optimized parameter corresponding Softmax regression models Fault type and abort situation predicted;
Prediction accuracy is calculated, and judges whether prediction accuracy is more than or equal to default accuracy threshold value;Wherein,
If prediction accuracy is more than or equal to default accuracy threshold value, directly utilizes and have determined that optimized parameter is corresponding Softmax regression models determine Single-phase Earth-fault Selection in Distribution Systems;
If prediction accuracy is less than default accuracy threshold value, increase iterations according to iteration step length is preset, and return Step 3 carries out route selection using Softmax regression models and training set and recognizes the determining optimized parameter of training, to determine optimized parameter pair The Softmax regression models answered.
In embodiments of the present invention, the sample data in test set is substituted into and assumes that function calculates its generic Probability, the maximum classification of select probability verify accuracy rate as prediction result.The circuit that will likely be broken down is compiled Number, it is denoted as 0~n, regression training is carried out to Softmax models using the tranining database for each numbering corresponding fault signature, It is basic number of iterations with 100 times, obtains the corresponding Softmax regression models of optimized parameter, trained model is utilized into test Data are tested.If accuracy rate is less than 95%, increases by 100 iterations, continue with Softmax regression models and instruction Practice collection progress route selection identification training and determine optimized parameter, and determine the corresponding Softmax regression models of optimized parameter, until accurate Until rate is higher than 95%.
The embodiment illustrated the present invention in detail below
Fig. 3 is the power distribution network typical overhead gauze frame structure chart according to embodiment of the present invention.As shown in figure 3, being one Typical 10kV distribution network structure structures, neutral grounding mode be directly grounded, fault ground type is metallic earthing. Each node location shown in the line, i.e., 646,645,632,633,634,611,684,652,671,680,692 and 675 are saved 12 recording type fault detectors of point place placement, collection voltages, electric current, phase, temporal information carry out between fault detector pair When, the synchronism of retention time record, and setting singlephase earth fault and same on 0~9 circuit shown in The Scarlet Letter in figure 3 respectively Step acquisition fault data.
It synthesizes to obtain the variation delta f of frequency by collected fault datai, the variation delta V of voltagei, the change of frequency Rate (Δ f/ Δs t)i, change rate (the Δ V/ Δs t) of voltagei, change rate (the Δ I/ Δs t) of electric currenti, the change rate of phase angleThere is change rate (the Δ P/ Δs t) of poweri, change rate (the Δ Q/ Δs t) of inactivityi, frequency with power change rate (Δf/ΔP)i, current harmonics distortion CTHD, voltage harmonic distortion VTHD, power factorAnd 3,5 times of voltage and current Harmonic component.Then, data are handled by rough set theory, determines that fault signature data include:The variable quantity of voltage ΔVi, change rate (the Δ I/ Δs t) of electric currenti, change rate (the Δ V/ Δs t) of voltageiAnd the change rate of phase angleTotally 4 A higher characteristic quantity of the degree of correlation.
After determining characteristic quantity, cost function is trained using gradient descent method, obtains optimized parameter, determine optimal The corresponding Softmax regression models of parameter.Then, accuracy is verified using the sample data in test set.
In an embodiment of the present invention, it is 95% to preset accuracy threshold value, and prediction result is divided into 10 classes, corresponds in Fig. 3 Shown respective feed connection, respectively 0~9.It is verified data separating point diagram by 500 iteration as shown in figure 4,1000 iteration As shown in figure 5, being overlapped as can be seen from Figure, in Fig. 4 more, it is overlapped less in Fig. 5, increasing for iterations can be by different characteristic number Classify according to corresponding abort situation, overlapping, that is, characteristic is unable to judge accurately abort situation classification, is kept completely separate then It can accurate judgement.Wherein, the judging nicety rate of Fig. 4 is 97%, is more than default accuracy threshold value 95%, then can directly utilize Determine that the corresponding Softmax regression models of optimized parameter determine Single-phase Earth-fault Selection in Distribution Systems.
After determining the corresponding Softmax regression models of optimized parameter, returned using the corresponding Softmax of the optimized parameter Return model to be predicted fault type and position according to the real time fail data of power grid, determines that power distribution network one-way earth fault selects Line.
Fig. 6 is the system for determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax according to embodiment of the present invention 600 structural schematic diagram.As shown in fig. 6, embodiments of the present invention offer determines power distribution network single-phase earthing based on Softmax The system 600 of failure line selection includes:Fault data acquiring unit 601, Database unit 602,603 and of model determination unit Failure line selection determination unit 604.Preferably, in the fault data acquiring unit 601, the multiple pre- of circuit in power distribution network is obtained If the fault data of node is each preset in node, wherein the fault data includes:Three-phase voltage data, three-phase electricity fluxion According to, the absolute time information that occurs of the phase data of voltage, the phase information of electric current and failure.
Preferably, wherein acquiring the fault data at each default node using recording type fault detector.
Preferably, in the Database unit 602, the fault data is handled, obtains fault signature number According to, and failure identification and fault signature database are established according to the fault signature data, fault type and abort situation mark, The wherein described fault signature data include multiple characteristic quantities.
Preferably, wherein the fault data acquiring unit, handles the fault data, fault signature number is obtained According to, including:
The fault data is handled, synthesis obtains failure volume, wherein the failure volume includes:Frequency Variable quantity, the variable quantity of voltage, the change rate of frequency, the change rate of voltage, the change rate of electric current, phase angle change rate, have The change rate of power, the change rate of inactivity, frequency is distorted with change rate, the current harmonics of power, voltage harmonic is distorted, power The each harmonic component of factor and voltage and current;
The failure volume is handled according to rough set theory, the low failure volume of the degree of correlation is got rid of, obtains Take fault signature data.
Preferably, in the model determination unit 603, the failure identification and the data in fault signature database are pressed Be divided into training set and test set according to fault type, and according to default iterations using Softmax regression models and training set into Row route selection identification training determines optimized parameter, to determine the corresponding Softmax regression models of optimized parameter.
Preferably, wherein the model determination unit, Softmax regression models and training are utilized according to default iterations Collection carries out route selection identification training and determines optimized parameter, to determine the corresponding Softmax regression models of optimized parameter, including:
Determine that the cost function of Softmax regression algorithms, cost function are:
Wherein, the sample of Softmax regression models comes from k class, shares m, then the training set being made of these samples For { (x(1),y(1)),(x(2),y(2)),…,(x(m),y(m)), whereinLabel:y(t)∈ { 1,2 ..., k }, for Given input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each point of x The probability that class result occurs;
Route selection identification training is carried out using gradient descent method to the cost function according to default iterations, is determined optimal Parameter obtains the corresponding Softmax regression models of optimized parameter.
Preferably, in the failure line selection determination unit 604, with the corresponding Softmax regression models of the optimized parameter Fault type and position are predicted according to the real time fail data of power grid, to determine power distribution network one-way earth fault route selection.
Preferably, wherein the system also includes:Accuracy validation unit,
The fault signature data of sample in test set are corresponded to using the optimized parameter corresponding Softmax regression models Fault type and abort situation predicted;Prediction accuracy is calculated, and it is default to judge whether prediction accuracy is more than or equal to Accuracy threshold value;Wherein, it if prediction accuracy is more than or equal to default accuracy threshold value, directly utilizes and has determined that optimized parameter pair The Softmax regression models answered determine Single-phase Earth-fault Selection in Distribution Systems;If prediction accuracy is less than default accuracy threshold value, Iterations are then increased according to default iteration step length, and returns to model determination unit and utilizes Softmax regression models and training set It carries out route selection identification training and determines optimized parameter, to determine the corresponding Softmax regression models of optimized parameter.
The system 600 and this hair that Single-phase Earth-fault Selection in Distribution Systems is determined based on Softmax of the embodiment of the present invention Another bright embodiment determines that the method 100 of Single-phase Earth-fault Selection in Distribution Systems is corresponding based on Softmax, herein not It repeats again.
The present invention is described by reference to a small amount of embodiment.However, it is known in those skilled in the art, as Defined by subsidiary Patent right requirement, in addition to the present invention other embodiments disclosed above are equally fallen the present invention's In range.
Normally, all terms used in the claims are all solved according to them in the common meaning of technical field It releases, unless in addition clearly being defined wherein.All references " one/described/be somebody's turn to do [device, component etc.] " are all opened ground It is construed at least one of described device, component etc. example, unless otherwise expressly specified.Any method disclosed herein Step need not all be run with disclosed accurate sequence, unless explicitly stated otherwise.

Claims (10)

1. a kind of method determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax, which is characterized in that the method packet It includes:
Step 1, the fault data for each presetting node in power distribution network in multiple default nodes of circuit is obtained, wherein the failure Data include:Three-phase voltage data, three-phase current data, the phase data of voltage, the phase information of electric current and failure occur Absolute time information;
Step 2, the fault data is handled, obtains fault signature data, and according to the fault signature data, failure Type and abort situation mark establish failure identification and fault signature database, wherein the fault signature data include multiple spies Sign amount;
Step 3, the data in the failure identification and fault signature database are divided into training set and test according to fault type Collection, and carry out route selection using Softmax regression models and training set according to default iterations and recognize the determining optimized parameter of training, To determine the corresponding Softmax regression models of optimized parameter;
Step 4, using the corresponding Softmax regression models of the optimized parameter according to the real time fail data of power grid to failure classes Type and position are predicted, to determine power distribution network one-way earth fault route selection.
2. according to the method described in claim 1, it is characterized in that, acquiring each default node using recording type fault detector The fault data at place.
3. according to the method described in claim 1, it is characterized in that, described handle the fault data, failure is obtained Characteristic, including:
The fault data is handled, synthesis obtains failure volume, wherein the failure volume includes:The change of frequency Change amount, the variable quantity of voltage, the change rate of frequency, the change rate of voltage, the change rate of electric current, phase angle change rate, have power Change rate, the change rate of inactivity, frequency be distorted with change rate, the current harmonics of power, voltage harmonic distortion, power factor And each harmonic component of voltage and current;
The failure volume is handled according to rough set theory, gets rid of the low failure volume of the degree of correlation, obtains event Hinder characteristic.
4. according to the method described in claim 1, it is characterized in that, the basis presets iterations using Softmax recurrence Model and training set carry out route selection identification training and determine optimized parameter, to determine the corresponding Softmax regression models of optimized parameter, Including:
Determine that the cost function of Softmax regression algorithms, cost function are:
Wherein, the sample of Softmax regression models comes from k class, shares m, then is { (x by the training set that these samples form(1),y(1)),(x(2),y(2)),…,(x(m),y(m)), whereinLabel:y(t)∈ { 1,2 ..., k }, for what is given Input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each classification results of x The probability of appearance;
Route selection identification training is carried out using gradient descent method to the cost function according to default iterations, determines optimal ginseng Number obtains the corresponding Softmax regression models of optimized parameter.
5. according to the method described in claim 1, it is characterized in that, the method further includes:
Utilize the event corresponding to the fault signature data of sample in test set of the corresponding Softmax regression models of the optimized parameter Barrier type and abort situation are predicted;
Prediction accuracy is calculated, and judges whether prediction accuracy is more than or equal to default accuracy threshold value;Wherein,
If prediction accuracy is more than or equal to default accuracy threshold value, directly utilizes and have determined that the corresponding Softmax of optimized parameter Regression model determines Single-phase Earth-fault Selection in Distribution Systems;
If prediction accuracy is less than default accuracy threshold value, increase iterations, and return to step 3 according to iteration step length is preset Route selection is carried out using Softmax regression models and training set and recognizes the determining optimized parameter of training, to determine that optimized parameter is corresponding Softmax regression models.
6. a kind of system determining Single-phase Earth-fault Selection in Distribution Systems based on Softmax, which is characterized in that the system packet It includes:
Fault data acquiring unit, for obtaining the number of faults for each presetting node in power distribution network in multiple default nodes of circuit According to wherein the fault data includes:Three-phase voltage data, three-phase current data, the phase data of voltage, the phase of electric current letter The absolute time information that breath and failure occur;
Database unit obtains fault signature data, and according to the failure for handling the fault data Characteristic, fault type and abort situation mark establish failure identification and fault signature database, wherein the fault signature Data include multiple characteristic quantities;
Model determination unit, for the data in the failure identification and fault signature database to be divided into instruction according to fault type Practice collection and test set, and true using Softmax regression models and training set progress route selection identification training according to default iterations Optimized parameter is determined, to determine the corresponding Softmax regression models of optimized parameter;
Failure line selection determination unit, for the real-time event with the corresponding Softmax regression models of the optimized parameter according to power grid Barrier data predict fault type and position, to determine power distribution network one-way earth fault route selection.
7. system according to claim 6, which is characterized in that acquire each default node using recording type fault detector The fault data at place.
8. system according to claim 6, which is characterized in that the fault data acquiring unit, to the fault data It is handled, obtains fault signature data, including:
The fault data is handled, synthesis obtains failure volume, wherein the failure volume includes:The change of frequency Change amount, the variable quantity of voltage, the change rate of frequency, the change rate of voltage, the change rate of electric current, phase angle change rate, have power Change rate, the change rate of inactivity, frequency be distorted with change rate, the current harmonics of power, voltage harmonic distortion, power factor And each harmonic component of voltage and current;
The failure volume is handled according to rough set theory, gets rid of the low failure volume of the degree of correlation, obtains event Hinder characteristic.
9. system according to claim 6, which is characterized in that the model determination unit, according to default iterations profit Route selection identification training is carried out with Softmax regression models and training set and determines optimized parameter, to determine that optimized parameter is corresponding Softmax regression models, including:
Determine that the cost function of Softmax regression algorithms, cost function are:
Wherein, the sample of Softmax regression models comes from k class, shares m, then is { (x by the training set that these samples form(1),y(1)),(x(2),y(2)),…,(x(m),y(m)), whereinLabel:y(t)∈ { 1,2 ..., k }, for what is given Input x, it is assumed that function estimates probability value p (y=j | x) for each classification j, for estimating each classification results of x The probability of appearance;
Route selection identification training is carried out using gradient descent method to the cost function according to default iterations, determines optimal ginseng Number obtains the corresponding Softmax regression models of optimized parameter.
10. system according to claim 6, which is characterized in that the system also includes:Accuracy validation unit,
For being corresponded to the fault signature data of sample in test set using the corresponding Softmax regression models of the optimized parameter Fault type and abort situation predicted;
For calculating prediction accuracy, and judge whether prediction accuracy is more than or equal to default accuracy threshold value;Wherein,
If prediction accuracy is more than or equal to default accuracy threshold value, directly utilizes and have determined that the corresponding Softmax of optimized parameter Regression model determines Single-phase Earth-fault Selection in Distribution Systems;
If prediction accuracy is less than default accuracy threshold value, increase iterations according to iteration step length is preset, and return to model Determination unit carries out route selection using Softmax regression models and training set and recognizes the determining optimized parameter of training, with the optimal ginseng of determination The corresponding Softmax regression models of number.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110659405A (en) * 2019-09-25 2020-01-07 南京源堡科技研究院有限公司 Network information acquisition method based on cloud environment
CN111160241A (en) * 2019-12-27 2020-05-15 华中科技大学 Power distribution network fault classification method, system and medium based on deep learning
CN111598166A (en) * 2020-05-18 2020-08-28 国网山东省电力公司电力科学研究院 Single-phase earth fault classification method and system based on principal component analysis and Softmax function
CN111796161A (en) * 2020-05-27 2020-10-20 山西浩然机电设备工程有限公司 Fault detection system and fault detection method for overhead cable
CN112924813A (en) * 2021-01-28 2021-06-08 国网浙江省电力有限公司绍兴供电公司 Power distribution network short-circuit fault monitoring method and device based on electrical data
CN116227538A (en) * 2023-04-26 2023-06-06 国网山西省电力公司晋城供电公司 Clustering and deep learning-based low-current ground fault line selection method and equipment

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103760464A (en) * 2014-01-07 2014-04-30 河南理工大学 Small current grounding system fault line selecting method based on analytic graph solving and SVM
EP2752674A1 (en) * 2013-01-03 2014-07-09 ABB Technology AG A detection method of a ground fault in an electric power distribution network
CN104297635A (en) * 2014-10-14 2015-01-21 河南理工大学 Fault line selection method for distribution network on basis of atom sparse decomposition and extreme learning machine
CN105759167A (en) * 2016-01-28 2016-07-13 江苏省电力公司南京供电公司 Wavelet neural network-based distribution network single-phase short circuit line selection method
CN106291234A (en) * 2016-07-29 2017-01-04 武汉大学 A kind of transmission line of electricity internal fault external fault based on convolutional neural networks judges and fault phase-selecting method
CN106951900A (en) * 2017-04-13 2017-07-14 杭州申昊科技股份有限公司 A kind of automatic identifying method of arrester meter reading
CN107766879A (en) * 2017-09-30 2018-03-06 中国南方电网有限责任公司 The MLP electric network fault cause diagnosis methods of feature based information extraction
CN107909118A (en) * 2017-12-11 2018-04-13 北京映翰通网络技术股份有限公司 A kind of power distribution network operating mode recording sorting technique based on deep neural network
CN107947156A (en) * 2017-11-24 2018-04-20 国网辽宁省电力有限公司 Based on the electric network fault critical clearing time method of discrimination for improving Softmax recurrence

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2752674A1 (en) * 2013-01-03 2014-07-09 ABB Technology AG A detection method of a ground fault in an electric power distribution network
CN103760464A (en) * 2014-01-07 2014-04-30 河南理工大学 Small current grounding system fault line selecting method based on analytic graph solving and SVM
CN104297635A (en) * 2014-10-14 2015-01-21 河南理工大学 Fault line selection method for distribution network on basis of atom sparse decomposition and extreme learning machine
CN105759167A (en) * 2016-01-28 2016-07-13 江苏省电力公司南京供电公司 Wavelet neural network-based distribution network single-phase short circuit line selection method
CN106291234A (en) * 2016-07-29 2017-01-04 武汉大学 A kind of transmission line of electricity internal fault external fault based on convolutional neural networks judges and fault phase-selecting method
CN106951900A (en) * 2017-04-13 2017-07-14 杭州申昊科技股份有限公司 A kind of automatic identifying method of arrester meter reading
CN107766879A (en) * 2017-09-30 2018-03-06 中国南方电网有限责任公司 The MLP electric network fault cause diagnosis methods of feature based information extraction
CN107947156A (en) * 2017-11-24 2018-04-20 国网辽宁省电力有限公司 Based on the electric network fault critical clearing time method of discrimination for improving Softmax recurrence
CN107909118A (en) * 2017-12-11 2018-04-13 北京映翰通网络技术股份有限公司 A kind of power distribution network operating mode recording sorting technique based on deep neural network

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
林莘 等: "超高压输电线路的潜供电弧频谱特性", 《高电压技术》 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110659405A (en) * 2019-09-25 2020-01-07 南京源堡科技研究院有限公司 Network information acquisition method based on cloud environment
CN111160241A (en) * 2019-12-27 2020-05-15 华中科技大学 Power distribution network fault classification method, system and medium based on deep learning
CN111160241B (en) * 2019-12-27 2022-08-12 华中科技大学 Power distribution network fault classification method, system and medium based on deep learning
CN111598166A (en) * 2020-05-18 2020-08-28 国网山东省电力公司电力科学研究院 Single-phase earth fault classification method and system based on principal component analysis and Softmax function
CN111598166B (en) * 2020-05-18 2023-10-17 国网山东省电力公司电力科学研究院 Single-phase earth fault classification method and system based on principal component analysis and Softmax function
CN111796161A (en) * 2020-05-27 2020-10-20 山西浩然机电设备工程有限公司 Fault detection system and fault detection method for overhead cable
CN111796161B (en) * 2020-05-27 2023-06-13 山西浩然机电设备工程有限公司 Fault detection system and fault detection method for overhead cable
CN112924813A (en) * 2021-01-28 2021-06-08 国网浙江省电力有限公司绍兴供电公司 Power distribution network short-circuit fault monitoring method and device based on electrical data
CN116227538A (en) * 2023-04-26 2023-06-06 国网山西省电力公司晋城供电公司 Clustering and deep learning-based low-current ground fault line selection method and equipment

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