CN113484685A - Power grid fault diagnosis method based on time sequence organization type P system - Google Patents

Power grid fault diagnosis method based on time sequence organization type P system Download PDF

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CN113484685A
CN113484685A CN202110809116.XA CN202110809116A CN113484685A CN 113484685 A CN113484685 A CN 113484685A CN 202110809116 A CN202110809116 A CN 202110809116A CN 113484685 A CN113484685 A CN 113484685A
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time
cell
event
fault diagnosis
power grid
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CN113484685B (en
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王涛
周科全
陈孝天
曹智博
程亮
刘力源
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Xihua University
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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
    • G01R31/08Locating faults in cables, transmission lines, or networks
    • G01R31/088Aspects of digital computing
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04SSYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00Systems supporting electrical power generation, transmission or distribution
    • Y04S10/50Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
    • Y04S10/52Outage or fault management, e.g. fault detection or location

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Abstract

The invention discloses a power grid fault diagnosis method based on a time sequence organization type P system, which combines the time sequence characteristic of an alarm signal with the organization type P system, can better process the problems of false alarm, missing alarm and the like in the alarm signal, can also reason out the time interval of the fault occurrence moment and accurately describe the fault evolution process.

Description

Power grid fault diagnosis method based on time sequence organization type P system
Technical Field
The invention belongs to the technical field of power grid fault diagnosis, and particularly relates to a power grid fault diagnosis method based on a time sequence organization type P system.
Background
The power system fault diagnosis is intended to identify a faulty element and evaluate the action behavior of a protection device through an alarm signal obtained by a control center. The fault alarm information is an important precondition for accurate and effective fault diagnosis of the power system. The fault alarm signal of the power system usually retrieves an operation signal from a Supervisory Control And Data Acquisition (SCADA) system, but with the gradual expansion of the scale of the power system And the increasing complexity of the structure, a large number of alarm signals are rushed into a dispatching center, And when the alarm signals are too many, the operation such as misjudgment And missing judgment is easy to occur to a dispatcher. Therefore, there is an increasing demand for rapid and accurate fault diagnosis of the power system.
Up to now, various fault diagnosis methods have been proposed at home and abroad, for example: expert systems, Petri nets, artificial neural networks, and the like. From most of the existing fault diagnosis methods, the following problems are also faced: (1) most of the existing fault diagnosis methods still cannot well process the situations of false alarm, missed alarm and the like of alarm signals; (2) the fault diagnosis model based on the traditional organization type P system has low interpretability on the action sequence and logic between protection devices, and the model complexity still has a reduced space; (3) nowadays, with the gradual expansion of the scale of a power grid, a power system needs to cope with various fault scenes when a fault occurs, and how to efficiently and accurately identify a fault element under the various fault scenes becomes a key of a fault diagnosis method.
The accuracy and the rapidity of the fault diagnosis of the power system have important significance for rapidly recovering power supply and maintaining the safe and stable operation of the power grid system after the fault occurs. Therefore, a great deal of research needs to be done on how to solve the situations of false alarm, missing alarm, and the like of fault alarm signals when the power grid is in actual operation and describe the action sequence and logic among the protection devices when the power system is in fault diagnosis.
Disclosure of Invention
Aiming at the defects in the prior art, the power grid fault diagnosis method based on the time sequence organization type P system solves the problems of false alarm, missing alarm and low diagnosis efficiency of fault signals in the conventional power grid fault diagnosis.
In order to achieve the purpose of the invention, the invention adopts the technical scheme that: a power grid fault diagnosis method based on a time sequence organization type P system comprises the following steps:
s1, determining a fault area in the power grid to be diagnosed through a junction analysis method, and further determining a suspicious fault element;
s2, in SCADA-based systemConstructing and correcting initial configuration vector W for action information and time sequence information of protection device0
S3, establishing a TTPS fault diagnosis model of each suspicious fault element according to the action sequence among the protection devices;
s4, establishing a connection matrix C and an initial configuration vector W according to the TTPS fault diagnosis model0Constructing a translation vector
Figure BDA0003167491370000021
S5, generating a fault node vector S according to the node distribution of each suspicious fault element in the TTPS fault diagnosis model;
s6, according to the transfer vector W1And a fault node vector S, and constructing a judgment vector WendAnd according to the judgment vector WendThe non-zero elements in the system determine the elements which send out the faults, and the fault diagnosis of the power grid is realized.
Further, the step S1 is specifically:
s11, setting the initial iteration number k to be 1;
s12, numbering each element in the power grid to be diagnosed in sequence, and constructing an element number set Pk
S13, from set PkIn which an arbitrary component number is taken and placed in a subset Q of component numberskJudging whether a closed circuit breaker exists in the power grid to be diagnosed and is connected with the currently selected element;
if yes, go to step S14;
if not, go to step S15;
s14, finding out all elements connected with the breaker in the power grid to be diagnosed, and adding the serial number of the elements to the set QkAnd returns to step S13;
s15, increasing the value of the search iteration number k by 1;
s16, collecting Qk-1From the set Pk-1Get a new component number set Pk
S17, judging the current new component number setPkWhether it is empty;
if yes, go to step S18;
if not, returning to the step S13;
s18 listing element number subset Q1,Q2,...,QkAll passive networks in the network are fault areas, and then fault elements are determined;
and the subscript K is the number of the element number subset obtained in the iteration process.
Further, the step S2 is specifically:
s21, constructing an initial configuration vector W based on the action information of the protection device in the SCADA system0
S22, judging whether the alarm signal in the power grid to be diagnosed meets the consistency of the time sequence characteristics;
if yes, go to step S23;
if not, go to step S24;
s23, using the initial configuration vector of the current structure as the final initial configuration vector W0Proceeding to step S3;
s24, correcting the initial configuration vector through the time sequence information of the alarm signal in the power grid to be diagnosed to obtain the corrected initial configuration vector W0The process proceeds to step S3.
Further, the initial configuration vector W in step S210Is represented by W0=(w10,w20,...,wm0)T,wi0Is the initial object of the tissue cell, i.e. the state value, w, representing the alarm signali0The value of (b) is 0 or 1, i is more than or equal to 1 and less than or equal to m; when the object w is initializedi0When the corresponding event occurs, i.e. the alarm signal corresponding to the node i is received, wi0Setting the node state value to 1, when starting the object wi0If the corresponding event does not occur, i.e. the alarm signal corresponding to the node i is not received, then wi0The node state value is set to 0.
Further, in the step S22, whether the timing characteristics of the alarm signal are consistent is judged based on the timing constraint and the timing inference rule for determining the alarm signal; wherein the timing constraints of the alarm signal include a time point constraint and a time distance constraint;
the expression of the time point constraint is as follows:
Figure BDA0003167491370000041
wherein T (i) represents the interval of the ith event
Figure BDA0003167491370000042
The internal generation is carried out in the process,
Figure BDA0003167491370000043
and
Figure BDA0003167491370000044
upper and lower bounds of T (i), respectively, when
Figure BDA0003167491370000045
If so, the ith event is a determined event and occurs at a specific time point;
the expression of the time-distance constraint is:
Figure BDA0003167491370000046
in the formula, D (i, j) represents that the interval between the ith event and the jth event occurrence time must be in the time interval
Figure BDA0003167491370000047
In the interior of said container body,
Figure BDA0003167491370000048
and
Figure BDA0003167491370000049
respectively representing the lower and upper bounds of D (i, j).
Further, the sequential reasoning rule comprises forward sequential reasoning and reverse sequential reasoning;
wherein, the forward time sequence reasoning is as follows:
knowing the time point constraint of the ith event and the time distance constraint between the ith event and the jth event, the time point constraint of the jth event is inferred as:
Figure BDA00031674913700000410
the reverse time sequence reasoning is as follows:
knowing the time point constraint of the jth event and the time distance constraint of the ith event and the jth event, the time point constraint of the jth event is inferred as:
Figure BDA0003167491370000051
further, in step S22, the expression of the consistency of the timing characteristics determined based on the timing constraint and the timing inference rule is:
Figure BDA0003167491370000052
in the formula ,mi and mjRespectively the ith and jth events, T (m), corresponding to the alarm signali) Is an event miConstraint on the time points of occurrence, D (m)i,mj) Is an event mi and mjIs constrained.
Further, in step S3, the expression of the TTPS fault diagnosis model Π with a degree m is as follows:
Π=(O,δi,E,T,i0,syn)
wherein O is a non-null target;
δiis the ith histiocyte, i is more than or equal to 1 and less than or equal to m, m is the total number of the histiocytes, the histiocytes in the TTPS fault diagnosis model pi comprise real cells and virtual cells, and the forms of the histiocytes are deltai=(wi0,Ri1) and δi=(wi0,Ri2);
wi0e.O represents an initial object multiple set in the tissue cell; ri1Representing a transport rule of a real cell, wherein the transport rule is (i, x/lambda, j), x and lambda respectively represent objects in a cell i and a cell j, the cell i and the cell j respectively correspond to the ith event and the jth event, the object lambda in the cell j represents an empty character string, and after the rule is executed, the object x in the cell i is transmitted to the empty character string lambda in the cell j; ri2Representing a transport rule of the virtual cells, which is in the form of (E, E/lambda, VC), wherein VC represents the virtual cells and represents main protection refusal or breaker refusal, E and lambda represent objects in the interstitial fluid environment E and the virtual cells VC, respectively, and the object lambda in the virtual cells VC represents an empty character string; after executing the rule, the object e in the interstitial fluid environment will be passed into the empty string λ in the virtual cell VC;
E={e1,...,endenotes the interstitial fluid environment of the tissue cells, where ede.O, d is more than or equal to 1 and less than or equal to n, represents the objects in the interstitial fluid environment, n is the total number of the objects in the interstitial fluid environment, when no direct communication channel exists between two cells, information exchange can be indirectly carried out through the environment, and when the actual histiocyte does not meet the transport rule Ri1Then, a transport rule (i, x/λ, E) is performed, where x and λ represent objects in cell i and interstitial fluid environment E, respectively; after executing the rule, the object x in cell i will pass into the empty string λ in interstitial fluid environment E;
T={tδ1,...,tδmdenotes the set of time points for each cell, with dimensions 1 × m, m being the total number of cells, T ═ T (T) (T ═ mδi)|δiE.g. delta } represents cell deltaiThe set of constraints on the point in time of,
Figure BDA0003167491370000061
represents cell deltaiThe occurrence time of the corresponding event should be in the time interval
Figure BDA0003167491370000062
Internal; d ═ D (δ)ij)|δijE δ represents a set of time-distance constraints, where
Figure BDA0003167491370000063
Represents cell deltaiAnd cell deltajThe occurrence time interval of the corresponding event should be in the time interval
Figure BDA0003167491370000064
Internal;
i0e { 1.. multidata, m } represents the labels of the output cells, each output cell labeled as a suspect faulty element;
Figure BDA0003167491370000065
the method represents the connection state set among the cells, the interconnected cells can exchange information, and all the cells (i, j) belong to syn, i is more than or equal to 1, and i is more than or equal to j when m is more than or equal to j.
Further, in step S4, the expression of the connection matrix C is set up as:
Figure BDA0003167491370000066
wherein ,cijRepresents cell deltaiAnd deltajThere is a positive correlation between, i.e. deltajThe corresponding event is a trigger deltaiCorresponding to the cause of the event, δiIs deltajA result produced after occurrence, cij0 means that there is no association between two cell nodes.
Further, the judgment vector W in the step S6endTransfer vector W1And performing logical AND operation on the fault node vector S to construct a judgment vector WendThe expression is as follows:
Wend=W1∧S
in the formula ,W1=(w11,w21,...,wm1)T,wi1=(ci1∧w11)∨(ci2∧w21)∨...∨(cim∧wm1),i=1,2,...,m;S=(s1,s2,...sn)T,si∈S,siI is 0 or 1, 1. ltoreq. n, when siWhen 1 represents δiFor a suspect faulty element, when siAnd 0 represents other device elements.
The invention has the beneficial effects that:
(1) the invention introduces time sequence factors on the basis of the traditional tissue type P system, provides a time sequence tissue-like P system (TTPS), adds time point constraint to an object in cells and adds time distance constraint to a connecting channel for information exchange between the cells in a diagnosis model of the TTPS, thereby effectively utilizing time sequence information to carry out time sequence characteristic consistency constraint check between all protection devices and solving the situations of false alarm, missing alarm and the like of fault alarm signals;
(2) virtual cell and interstitial fluid environments are introduced into the TTPS, and four incidence relations which can describe action sequences and logics among various protection devices are provided on the basis, so that a new graphical modeling mode is provided, the model explanatory performance is improved, and the model complexity is reduced;
(3) the fault element is calculated through the logic operation among the initial configuration vector, the connection matrix and the fault node vector so as to deal with fault diagnosis under various fault scenes, and the fault diagnosis efficiency is improved. Therefore, by combining the time sequence characteristic of the alarm signal with the tissue type P system, the problems of false alarm, missing report and the like in the alarm signal can be well processed, the time interval of the fault occurrence time can be deduced, and the fault evolution process can be accurately described.
Drawings
Fig. 1 is a flowchart of a power grid fault diagnosis method based on a time-series organization type P system provided by the present invention.
Fig. 2 is a schematic diagram of a simple power transmission system and a TTPS fault diagnosis model provided by the present invention.
Fig. 3 is a schematic diagram of four association relationships in the TTPS fault diagnosis model provided by the present invention.
Fig. 4 is a schematic diagram of a standard IEEE14 node according to the present invention.
Fig. 5 is a schematic diagram of a TTPS fault diagnosis model of bus B13 provided by the present invention.
Detailed Description
The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.
Example 1:
the power grid fault diagnosis method based on the time sequence organization type P system provided by the embodiment of the invention comprises the following steps:
s1, determining a fault area in the power grid to be diagnosed through a junction analysis method, and further determining a suspicious fault element;
s2, constructing and correcting the initial configuration vector W based on the action information and the time sequence information of the protection device in the SCADA system0
S3, establishing a TTPS fault diagnosis model of each suspicious fault element according to the action sequence among the protection devices;
s4, establishing a connection matrix C and an initial configuration vector W according to the TTPS fault diagnosis model0Constructing a translation vector
Figure BDA0003167491370000081
S5, generating a fault node vector S according to the node distribution of each suspicious fault element in the TTPS fault diagnosis model;
s6, according to the transfer vector W1And a fault node vector S, and constructing a judgment vector WendAnd according to the judgment vector WendThe non-zero elements in the system determine the elements which send out the faults, and the fault diagnosis of the power grid is realized.
It should be noted that, in the process of executing the above steps, steps S2 and S3 are both performed based on the result obtained in step S1, and step S2 and step S3 are in parallel, and the sequence shown as S2 to S3 in this embodiment is only for forming a coherent execution logic and facilitating understanding of the solution of the present application, and in the actual implementation process, steps S2 and S3 may be executed simultaneously as needed.
Step S1 of the embodiment of the present invention specifically includes:
s11, setting the initial iteration number k to be 1;
s12, numbering each element in the power grid to be diagnosed in sequence, and constructing an element number set Pk
S13, from set PkIn which an arbitrary component number is taken and placed in a subset Q of component numberskJudging whether a closed circuit breaker exists in the power grid to be diagnosed and is connected with the currently selected element;
if yes, go to step S14;
if not, go to step S15;
s14, finding out all elements connected with the breaker in the power grid to be diagnosed, and adding the serial number of the elements to the set QkAnd returns to step S13;
s15, increasing the value of the search iteration number k by 1;
s16, collecting Qk-1From the set Pk-1Get a new component number set Pk
S17, judging the current new component number set PkWhether it is empty;
if yes, go to step S18;
if not, returning to the step S13;
s18 listing element number subset Q1,Q2,...,QkAll passive networks in the network are fault areas, and then fault elements are determined;
and the subscript K is the number of the element number subset obtained in the iteration process.
Step S2 in the embodiment of the present invention specifically includes:
s21, constructing an initial configuration vector W based on the action information of the protection device in the SCADA system0
S22, judging whether the alarm signal in the power grid to be diagnosed meets the consistency of the time sequence characteristics;
if yes, go to step S23;
if not, go to step S24;
s23, using the initial configuration vector of the current structure as the final initial configuration vector W0Proceeding to step S3;
s24, correcting the initial configuration vector through the time sequence information of the alarm signal in the power grid to be diagnosed to obtain the corrected initial configuration vector W0The process proceeds to step S3.
In step S21, the SCADA system provides initial status information as initial access based on the TTPS fault diagnosis method, and the initial configuration vector W0Is represented by W0=(w10,w20,...,wm0)T,wi0Is the initial object of the tissue cell, i.e. the state value, w, representing the alarm signali0The value of (b) is 0 or 1, i is more than or equal to 1 and less than or equal to m; when the object w is initializedi0When the corresponding event occurs, i.e. the alarm signal corresponding to the node i is received, wi0Setting the node state value to 1, when starting the object wi0If the corresponding event does not occur, i.e. the alarm signal corresponding to the node i is not received, then wi0The node state value is set to 0.
In the above step S22, it is determined whether or not the timing characteristics of the alarm signal are consistent based on the timing constraint and the timing inference rule that determine the timing; wherein the timing constraints of the alarm signal include a time point constraint and a time distance constraint;
the expression of the time point constraint is as follows:
Figure BDA0003167491370000101
wherein T (i) represents the interval of the ith event
Figure BDA0003167491370000102
The internal generation is carried out in the process,
Figure BDA0003167491370000103
and
Figure BDA0003167491370000104
upper and lower bounds of T (i), respectively, when
Figure BDA0003167491370000105
If so, the ith event is a determined event and occurs at a specific time point;
the expression of the time-distance constraint is:
Figure BDA0003167491370000106
in the formula, D (i, j) represents that the interval between the ith event and the jth event occurrence time must be in the time interval
Figure BDA0003167491370000107
In the interior of said container body,
Figure BDA0003167491370000108
and
Figure BDA0003167491370000109
respectively representing the lower and upper bounds of D (i, j);
because the time point constraint and the time distance constraint are both defined by intervals, the time sequence characteristic constraint inference rule is defined based on the calculation rule of the intervals, and the time sequence inference rule in the embodiment comprises forward time sequence inference and reverse time sequence inference;
wherein, the forward time sequence reasoning is as follows:
knowing the time point constraint of the ith event and the time distance constraint between the ith event and the jth event, the time point constraint of the jth event is inferred as:
Figure BDA0003167491370000111
the reverse time sequence reasoning is as follows:
knowing the time point constraint of the jth event and the time distance constraint of the ith event and the jth event, the time point constraint of the jth event is inferred as:
Figure BDA0003167491370000112
based on the constraint and inference rules, the alarm signals have sequential logic association, and the sequential logic relationship can be used for judging the uncertain conditions such as the false operation of a protection device or a circuit breaker, the false alarm of the alarm signals and the like; the expression of the timing characteristic consistency determined based on the timing constraint and the timing reasoning rule is as follows:
Figure BDA0003167491370000113
in the formula ,mi and mjRespectively the ith and jth events, T (m), corresponding to the alarm signali) Is an event miConstraint on the time points of occurrence, D (m)i,mj) Is an event mi and mjIs constrained.
The meaning of the above time sequence consistency expression is: if event mjOccurs at T (m)j) At time, then T (m)j) The timing characteristic consistency constraint, namely T (m), needs to be satisfiedj)∈(T(mi)+D(mi,mj)). If so, event mjTime T (m) of occurrence ofj) Completed within a specified time limit; otherwise, the corresponding alarm signal belongs to a false alarm message.
In step S3 of the present embodiment, the expression of the TTPS fault diagnosis model Π having one degree m is:
Π=(O,δi,E,T,i0,syn)
wherein O is a non-null target;
δiis the ith histiocyte, i is more than or equal to 1 and less than or equal to m, m is the total number of the histiocytes, the histiocytes in the TTPS fault diagnosis model pi comprise real cells and virtual cells, and the forms of the histiocytes are deltai=(wi0,Ri1) and δi=(wi0,Ri2);
wi0e.O represents an initial object multiple set in the tissue cell; ri1Representing a transport rule of a real cell, wherein the transport rule is (i, x/lambda, j), x and lambda respectively represent objects in a cell i and a cell j, the cell i and the cell j respectively correspond to the ith event and the jth event, the object lambda in the cell j represents an empty character string, and after the rule is executed, the object x in the cell i is transmitted to the empty character string lambda in the cell j; ri2Representing a transport rule of the virtual cells, which is in the form of (E, E/lambda, VC), wherein VC represents the virtual cells and represents main protection refusal or breaker refusal, E and lambda represent objects in the interstitial fluid environment E and the virtual cells VC, respectively, and the object lambda in the virtual cells VC represents an empty character string; after executing the rule, the object e in the interstitial fluid environment will be passed into the empty string λ in the virtual cell VC;
E={e1,...,endenotes the interstitial fluid environment of the tissue cells, where ede.O, d is more than or equal to 1 and less than or equal to n, represents the objects in the interstitial fluid environment, n is the total number of the objects in the interstitial fluid environment, when no direct communication channel exists between two cells, information exchange can be indirectly carried out through the environment, and when the actual histiocyte does not meet the transport rule Ri1Then, a transport rule (i, x/λ, E) is performed, where x and λ represent objects in cell i and interstitial fluid environment E, respectively; after executing the rule, the object x in cell i will pass into the empty string λ in interstitial fluid environment E;
T={tδ1,...,tδmdenotes the set of time points for each cell, with dimensions 1 × m, m being the total number of cells, T ═ T (T) (T ═ mδi)|δiE.g. delta } represents cell deltaiThe set of constraints on the point in time of,
Figure BDA0003167491370000121
represents cell deltaiThe occurrence time of the corresponding event should be in the time interval
Figure BDA0003167491370000122
Internal; d ═ D (δ)ij)|δijE δ represents a set of time-distance constraints, where
Figure BDA0003167491370000123
Represents cell deltaiAnd cell deltajThe occurrence time interval of the corresponding event should be in the time interval
Figure BDA0003167491370000124
Internal;
i0e { 1.. multidata, m } represents the labels of the output cells, each output cell labeled as a suspect faulty element;
Figure BDA0003167491370000131
the method represents the connection state set among the cells, the interconnected cells can exchange information, and all the cells (i, j) belong to syn, i is more than or equal to 1, and i is more than or equal to j when m is more than or equal to j.
The TTPS fault diagnosis model is shown in fig. 2, and exhibits a causal relationship between a suspected fault element and a protection device by using TTPS modeling according to the action information of the protection device provided by the SCADA system. The modeling concept of the method of the present invention is illustrated below by taking as an example a simple power transmission system as shown in fig. 2(a), which includes a line L, two circuit breakers CB1 and CB2, two main protectors MLR1 and MLR2, and two backup protectors BLR1 and BLR 2. The protection of the line is configured as: if the line L has a fault, the MLR1 and the MLR2 act to trip out the circuit breakers CB1 and CB 2; if MLR1 and MLR2 fail to operate normally, then BLR1 and BLR2 will operate to trip circuit breakers CB1 and CB 2.
The fault diagnosis model of this power transmission system is established based on TTPS, as shown in fig. 2(b), in which the solid directional arcs represent causal relationships between the individual protection devices, and the time intervals on the directional arcs thereofThe connection channels with different incidence relations have different time distance constraint intervals, and the blue dotted line represents the direction of performing the inference algorithm. The model consists of 9 cells and the causal relationship logic between a suspected faulty element and its protection device is modeled by TTPS. Firstly, judging a line L in a power failure area as a suspicious element by using protection uploaded to an SCADA system and action information of a circuit breaker, wherein a cell delta corresponding to the line L1Designated as output cell, VC (delta)12) Represents cell delta1The event represented occurs, and cell delta2The represented event does not occur.
Considering the time sequence characteristics, the tissue cells in the TTPS and the connecting channels connecting the tissue cells have the time property. And the connection channels with different association relations have different timing attributes, so four association relations of the TTPS are defined.
The four associations of TTPS are defined as shown in fig. 3:
compared with the TPS, the TTPS introduces a time point constraint and a time distance constraint to improve the fault tolerance of a diagnosis model, so that forward reasoning and time reasoning can be carried out together.
For better understanding of the TTPS model, four correlations in TTPS are described in detail. FIG. 3- (a) shows a faulty equipment node δjInduce a corresponding protection node deltaiAn action; FIG. 3- (b) shows the protection node δjTriggering the corresponding breaker cell deltaiAn action; FIG. 3- (c) shows the breaker cell deltajFailure-induced corresponding failure-protected cell deltaiAction, VC cell represents breaker cell deltaj(ii) a rejection-triggered cell; FIG. 3- (d) shows the primary protective cell deltajFailure to initiate the corresponding backup protective cell deltaiAction, VC cell represents the primary protective cell deltajThe primed cells were rejected.
In the TTPS, the connection channels with different association relations have different time interval attributes, and the corresponding time distance constraint is as follows:
(1)
Figure BDA0003167491370000141
(failure occurrence, primary protection action) E [10,40]ms;
(2)
Figure BDA0003167491370000142
(protection action, breaker action) e [40,60 ]]ms;
(3)
Figure BDA0003167491370000143
(circuit breaker failure, failsafe action) e [210,240]m;
(4)
Figure BDA0003167491370000144
(Primary protection rejection, backup protection action) E [940,1030]ms. In step S4 of the present embodiment, in order to better describe the communication rule and cause-effect relationship of each cell, a connection matrix C is introduced, whose expression is:
Figure BDA0003167491370000145
wherein ,cijRepresents cell deltaiAnd deltajThere is a positive correlation between, i.e. deltajThe corresponding event is a trigger deltaiCorresponding to the cause of the event, δiIs deltajA result produced after occurrence, cij0 means that there is no association between two cell nodes.
In step S4 of the present embodiment, the vector W is transferred1Comprises the following steps:
Figure BDA0003167491370000146
wherein ,W1=(w11,w21,...,wm1)T,wi1=(ci1∧w11)∨(ci2∧w21)∨...∨(cim∧wm1) I 1, 2.. said, m; for the
Figure BDA0003167491370000147
Or 1, the definitions a ═ b ═ min (a, b) and a ^ b ═ max (a, b);
W0=(w10,w20,...,wm0)Tinitial configuration vector W constructed to represent action information of protection devices provided by SCADA system0
C=(cij)m×mc ij0 or 1, which represents the communication rule and the causal relationship of the cells corresponding to each event;
in step S5 of this embodiment, the node distribution of each faulty element in the TTPS is obtained, and a faulty node vector S is generated according to the distribution, which reflects the node distribution of each suspected faulty element in the TTPS, where S ═ S (S ═ S)1,s2,...sn)T,si∈S,siI is 0 or 1, 1. ltoreq. n, when siWhen 1 represents δiFor a suspect faulty element, when siWhen 0, represents other device elements;
determination vector W in step S6 of the present embodimentendTransfer vector W1And performing logical AND operation on the fault node vector S to construct a judgment vector WendThe expression is as follows:
Wend=W1∧S
example 2:
in this embodiment, a standard IEEE14 node system is taken as a diagnosis target, and taking example 1 as an example, a specific calculation process is given to facilitate detailed understanding, and fig. 4 is a standard IEEE14 node network topology diagram.
Table 1 shows the preset failure scenario and the results of the failure diagnosis element in this embodiment
Table 1 preset fault scenario and faulty element diagnostic results of example 1
Figure BDA0003167491370000151
Firstly, after a fault occurs, a power failure area is judged by using a junction analysis method, and a suspected fault element bus B13, a line L1213 and a line L1314 are obtained. Establishing a TTPS fault diagnosis model of the bus B13, as shown in FIG. 5:
based on the TTPS fault diagnosis model of bus B13 of fig. 5, a 14 × 14 connection matrix C is established, which is represented as follows:
Figure BDA0003167491370000161
setting an initial configuration vector as W according to action information of a protection device and a breaker provided by the SCADA system0=(0,1,1,0,0,0,1,0,0,0,1,1,1,1)T
After the time sequence consistency constraint check, all the protection devices accord with the time sequence consistency constraint condition without correcting the initial configuration vector W0=(0,1,1,0,0,0,1,0,0,0,1,1,1,1)T
Connection matrix C and initial configuration vector W0Calculating to obtain a transfer vector W1
Figure BDA0003167491370000162
Generating a fault node vector S, wherein non-0 elements in the S are a bus B13 and a virtual cell delta12
Generating a fault node vector S and a transfer vector W1Performing logical AND operation to obtain a judgment vector Wend
Wend=W1∧S=(1,0,0,0,0,0,0,0,0,0,0,0,0,0)
The bus B13 is judged to have a fault.
And judging that the circuit L1213 and the circuit breaker CB1314 reject action in the same way.
Analyzing the fault evolution process, taking the time scale of the received first alarm as a reference point, and performing time sequence reasoning through analysis, wherein the actual fault evolution process comprises the following steps: bus B13 failed during [ -20, -10], bus main protection B13m acted at 0ms and triggered circuit breakers CB1312 and CB1306 to act at 48ms and 51ms, respectively, circuit breaker CB1314 rejected triggering far backup protection L1413s at 1989ms and tripped circuit breaker CB1413 at 2041 ms.

Claims (10)

1. A power grid fault diagnosis method based on a time sequence organization type P system is characterized by comprising the following steps:
s1, determining a fault area in the power grid to be diagnosed through a junction analysis method, and further determining a suspicious fault element;
s2, constructing and correcting the initial configuration vector W based on the action information and the time sequence information of the protection device in the SCADA system0
S3, establishing a TTPS fault diagnosis model of each suspicious fault element according to the action sequence among the protection devices;
s4, establishing a connection matrix C and an initial configuration vector W according to the TTPS fault diagnosis model0Constructing a translation vector
Figure FDA0003167491360000011
S5, generating a fault node vector S according to the node distribution of each suspicious fault element in the TTPS fault diagnosis model;
s6, according to the transfer vector W1And a fault node vector S, and constructing a judgment vector WendAnd according to the judgment vector WendThe non-zero elements in the system determine the elements which send out the faults, and the fault diagnosis of the power grid is realized.
2. The power grid fault diagnosis method based on the time-series organization type P system according to claim 1, wherein the step S1 specifically comprises:
s11, setting the initial iteration number k to be 1;
s12, numbering each element in the power grid to be diagnosed in sequence, and constructing an element number set Pk
S13, from set PkIn which an arbitrary component number is taken and placed in a subset Q of component numberskIn the method, whether the power grid to be diagnosed is in the power grid or not is judgedThe circuit breaker with the closed circuit breaker is connected with the currently selected element;
if yes, go to step S14;
if not, go to step S15;
s14, finding out all elements connected with the breaker in the power grid to be diagnosed, and adding the serial number of the elements to the set QkAnd returns to step S13;
s15, increasing the value of the search iteration number k by 1;
s16, collecting Qk-1From the set Pk-1Get a new component number set Pk
S17, judging the current new component number set PkWhether it is empty;
if yes, go to step S18;
if not, returning to the step S13;
s18 listing element number subset Q1,Q2,...,QkAll passive networks in the network are fault areas, and then fault elements are determined;
and the subscript K is the number of the element number subset obtained in the iteration process.
3. The power grid fault diagnosis method based on the time-series organization type P system according to claim 1, wherein the step S2 specifically comprises:
s21, constructing an initial configuration vector W based on the action information of the protection device in the SCADA system0
S22, judging whether the alarm signal in the power grid to be diagnosed meets the consistency of the time sequence characteristics;
if yes, go to step S23;
if not, go to step S24;
s23, using the initial configuration vector of the current structure as the final initial configuration vector W0Proceeding to step S3;
s24, correcting the initial configuration vector through the time sequence information of the alarm signal in the power grid to be diagnosed to obtain the corrected initial configuration vector W0The process proceeds to step S3.
4. The grid fault diagnosis method based on time-series organization type P system as claimed in claim 3, wherein the initial configuration vector W in step S210Is represented by W0=(w10,w20,...,wm0)T,wi0Is the initial object of the tissue cell, i.e. the state value, w, representing the alarm signali0The value of (b) is 0 or 1, i is more than or equal to 1 and less than or equal to m; when the object w is initializedi0When the corresponding event occurs, i.e. the alarm signal corresponding to the node i is received, wi0Setting the node state value to 1, when starting the object wi0If the corresponding event does not occur, i.e. the alarm signal corresponding to the node i is not received, then wi0The node state value is set to 0.
5. The grid fault diagnosis method based on time-series organization type P system as claimed in claim 3, wherein in step S22, whether the time-series characteristics are consistent is judged based on the time-series constraint and the time-series inference rule for determining the alarm signal; wherein the timing constraints of the alarm signal include a time point constraint and a time distance constraint;
the expression of the time point constraint is as follows:
Figure FDA0003167491360000031
wherein T (i) represents the interval of the ith event
Figure FDA0003167491360000032
The internal generation is carried out in the process,
Figure FDA0003167491360000033
and
Figure FDA0003167491360000034
upper and lower bounds of T (i), respectively, when
Figure FDA0003167491360000035
If so, the ith event is a determined event and occurs at a specific time point;
the expression of the time-distance constraint is:
Figure FDA0003167491360000036
in the formula, D (i, j) represents that the interval between the ith event and the jth event occurrence time must be in the time interval
Figure FDA0003167491360000037
In the interior of said container body,
Figure FDA0003167491360000038
and
Figure FDA0003167491360000039
respectively representing the lower and upper bounds of D (i, j).
6. The power grid fault diagnosis method based on the time sequence organization type P system as claimed in claim 5, wherein the time sequence inference rule comprises forward time sequence inference and reverse time sequence inference;
wherein, the forward time sequence reasoning is as follows:
knowing the time point constraint of the ith event and the time distance constraint between the ith event and the jth event, the time point constraint of the jth event is inferred as:
Figure FDA00031674913600000310
the reverse time sequence reasoning is as follows:
knowing the time point constraint of the jth event and the time distance constraint of the ith event and the jth event, the time point constraint of the jth event is inferred as:
Figure FDA0003167491360000041
7. the power grid fault diagnosis method based on the time-series organization type P system as claimed in claim 3, wherein in the step S22, the expression of the consistency of the time-series characteristics determined based on the time-series constraint and the time-series inference rule is as follows:
Figure FDA0003167491360000042
in the formula ,mi and mjRespectively the ith and jth events, T (m), corresponding to the alarm signali) Is an event miConstraint on the time points of occurrence, D (m)i,mj) Is an event mi and mjIs constrained.
8. The power grid fault diagnosis method based on the time-series organization type P system according to claim 1, wherein in step S3, the expression of the TTPS fault diagnosis model Π with one degree m is:
Π=(O,δi,E,T,i0,syn)
wherein O is a non-null target;
δiis the ith histiocyte, i is more than or equal to 1 and less than or equal to m, m is the total number of the histiocytes, the histiocytes in the TTPS fault diagnosis model pi comprise real cells and virtual cells, and the forms of the histiocytes are deltai=(wi0,Ri1) and δi=(wi0,Ri2);
wi0e.O represents an initial object multiple set in the tissue cell; ri1Representing the transport rule of the real cell, and the form is (i, x/lambda, j), x and lambda represent the objects in the cell i and the cell j respectively, the cell i and the cell j respectively correspond to the ith event and the jth event, and the object lambda in the cell j represents an empty characterA string, after the rule is executed, the object x in cell i will be passed into the empty string λ in cell j; ri2Representing a transport rule of the virtual cells, which is in the form of (E, E/lambda, VC), wherein VC represents the virtual cells and represents main protection refusal or breaker refusal, E and lambda represent objects in the interstitial fluid environment E and the virtual cells VC, respectively, and the object lambda in the virtual cells VC represents an empty character string; after executing the rule, the object e in the interstitial fluid environment will be passed into the empty string λ in the virtual cell VC;
E={e1,...,endenotes the interstitial fluid environment of the tissue cells, where ede.O, d is more than or equal to 1 and less than or equal to n, represents the objects in the interstitial fluid environment, n is the total number of the objects in the interstitial fluid environment, when no direct communication channel exists between two cells, information exchange can be indirectly carried out through the environment, and when the actual histiocyte does not meet the transport rule Ri1Then, a transport rule (i, x/λ, E) is performed, where x and λ represent objects in cell i and interstitial fluid environment E, respectively; after executing the rule, the object x in cell i will pass into the empty string λ in interstitial fluid environment E;
T={tδ1,...,tδmdenotes the set of time points for each cell, with dimensions 1 × m, m being the total number of cells, T ═ T (T) (T ═ mδi)|δiE.g. delta } represents cell deltaiThe set of constraints on the point in time of,
Figure FDA0003167491360000051
represents cell deltaiThe occurrence time of the corresponding event should be in the time interval
Figure FDA0003167491360000052
Internal; d ═ D (δ)ij)|δijE δ represents a set of time-distance constraints, where
Figure FDA0003167491360000053
Represents cell deltaiAnd cell deltajThe occurrence time interval of the corresponding event should be in the time interval
Figure FDA0003167491360000054
Internal;
i0e { 1.. multidata, m } represents the labels of the output cells, each output cell labeled as a suspect faulty element;
Figure FDA0003167491360000055
the method represents the connection state set among the cells, the interconnected cells can exchange information, and all the cells (i, j) belong to syn, i is more than or equal to 1, and i is more than or equal to j when m is more than or equal to j.
9. The power grid fault diagnosis method based on the time-series organization type P system as claimed in claim 8, wherein in the step S4, the expression of the connection matrix C is:
Figure FDA0003167491360000056
wherein ,cijRepresents cell deltaiAnd deltajThere is a positive correlation between, i.e. deltajThe corresponding event is a trigger deltaiCorresponding to the cause of the event, δiIs deltajA result produced after occurrence, cij0 means that there is no association between two cell nodes.
10. The grid fault diagnosis method based on time-series organization type P system according to claim 9, wherein the judgment vector W in the step S6endTransfer vector W1And performing logical AND operation on the fault node vector S to construct a judgment vector WendThe expression is as follows:
Wend=W1∧S
in the formula ,W1=(w11,w21,...,wm1)T,wi1=(ci1∧w11)∨(ci2∧w21)∨...∨(cim∧wm1),i=1,2,...,m;S=(s1,s2,...sn)T,si∈S,siI is 0 or 1, 1. ltoreq. n, when siWhen 1 represents δiFor a suspect faulty element, when siAnd 0 represents other device elements.
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