A power grid fault diagnosis method based on considering timing information

Abstract

The application is a power grid fault diagnosis method based on time sequence information, comprising the following steps: obtaining the action state of the protection corresponding to the suspicious element and the action state of the circuit breaker corresponding to the suspicious element, obtaining the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker; respectively analyzing the action state of the protection and the circuit breaker to obtain an action state analysis model; respectively analyzing the alarm information of the protection and the circuit breaker to obtain an alarm information analysis model. The power grid fault diagnosis method based on time sequence information improves the generality and accuracy of the information physical model in power grid fault diagnosis by starting with the analysis of the power grid model through the reception of the information model by dispatch personnel, and generalizing the originally complex model.

Description

Technical Field

[0001] This invention relates to the field of power grid fault diagnosis technology, specifically a power grid fault diagnosis method based on timing and sequence information. Background Technology

[0002] Power grid fault diagnosis plays a crucial role in the rapid recovery of power systems and ensuring their normal operation. However, it has long been a challenge for power system researchers. The difficulties lie in: solving models that integrate protection and circuit breaker failures and maloperations, and ensuring the non-uniqueness of the diagnosed solutions.

[0003] When a power grid experiences complex faults, such as multiple faults or false alarms and missed alarms, the difficulty of fault diagnosis increases significantly. The following diagnostic methods are generally used for power grid faults: utilizing the timing information and causal relationships of protection actions and circuit breaker tripping to identify missed and false alarms and optimize diagnostic results; constructing a fault diagnosis mathematical model based on outward reasoning and concise covering set theory to process the time characteristics of alarm information, and representing the relationship between faulty components, alarm information, and their time characteristics in the form of a time diagram. A 0-1 programming mathematical model for power grid fault diagnosis, utilizing only the timing information of circuit breaker tripping, first performs real-time connection analysis to identify passive regions as fault areas, and then transforms fault diagnosis into a mathematical programming problem to solve.

[0004] The above-mentioned fault diagnosis methods are applicable to power systems where protection action information is incomplete or unavailable, and they have high requirements for time period division and data synchronization. They can usually only identify the fault area, and the accuracy of power grid fault diagnosis needs to be improved. Summary of the Invention

[0005] This invention addresses the technical problems existing in the prior art by providing a power grid fault diagnosis method based on timing and sequence information. This solves the problem that the existing fault diagnosis methods have poor applicability in power system applications and are difficult to accurately diagnose fault points.

[0006] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A power grid fault diagnosis method based on timing and sequence information, comprising the following steps:

[0007] Obtain the operating status of the protection corresponding to the suspicious element and the operating status of the circuit breaker corresponding to the suspicious element; obtain the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker.

[0008] The operating status of the protection and circuit breaker is analyzed separately to obtain the operating status analysis model;

[0009] Alarm information is analyzed for both protection devices and circuit breakers to obtain an alarm information analysis model;

[0010] By combining the action state analysis model and the alarm information analysis model, a physical model of power grid fault information is constructed.

[0011] The objective function of the power grid fault information physical model is established, and the objective function is solved in combination with the power grid fault information physical model to obtain the fault diagnosis result.

[0012] Based on the above technical solution, the present invention can be further improved as follows.

[0013] Furthermore, the operation status analysis of the protection and circuit breaker includes operation status rule analysis and operation status timing analysis.

[0014] Furthermore, the operation status analysis of the protection and circuit breaker includes operation status rule analysis and operation status timing analysis.

[0015] Furthermore, the action state rule parsing includes:

[0016] The action status rules of the protection are analyzed to obtain the expected actions of the main protection, near backup protection, far backup protection and circuit breaker failure protection corresponding to the suspicious components;

[0017] The circuit breaker's operating state rules are parsed to obtain the circuit breaker's expected operation.

[0018] Furthermore, the calculation process for the expected actions of the main protection, near backup protection, far backup protection, and circuit breaker failure protection corresponding to the suspected component is as follows:

[0019] Let element s d,k The main protection is r i If the suspected component s d,k Fault (s) d,k =1), then its main protection r i The action should be performed, and its expected action is... for:

[0020]

[0021] Let element s d,k Near backup protection is r j When element s d,k Fault occurred and the main protection r i When no action is taken, s d,k =1, r i =0, then the nearest backup protection r j The action should be performed, and its expected action is... It can be parsed as follows:

[0022]

[0023] Let element sd,k The remote backup protection is r l r l For s d,k And for s d,k Adjacent components within the protected area d,l Provides remote backup protection, among which,

[0024] If s d,k Fault (s) d,k =1), and its corresponding main protection r i and near backup protection r j If no action is taken, then remote backup protection will be activated. l Action is required;

[0025] If element s d,l ∈Z(r l ,s l ) fault, and r l to s l All circuit breakers p(r) on the associated path l ,s l All are closed states, when s d,k Adjacent elements d,l If a fault occurs and its associated path is connected, then the remote backup protection r l Action is required;

[0026] Therefore, the expectation of its action for:

[0027]

[0028] If protect r x Action-driven circuit breaker c k If the circuit breaker trips and fails to operate, then the circuit breaker failure protection is activated. k The protection fails when it should have been activated. for:

[0029]

[0030] R indicates the status of the protection corresponding to the suspected element, and C indicates the status of the circuit breaker corresponding to the suspected element.

[0031] Furthermore, the calculation process for the expected operation of the circuit breaker is as follows:

[0032] Circuit breaker c k Corresponding arbitrary protection r x Action, and cause circuit breaker c k If the circuit breaker trips, then circuit breaker c will trip at this time. k The circuit breaker should trip (c) k =1), then the expected operation f of its circuit breaker. ckRepresented as:

[0033]

[0034] R indicates the status of the protection corresponding to the suspected element, and C indicates the status of the circuit breaker corresponding to the suspected element.

[0035] Furthermore, based on the expected operation of the main protection, near backup protection, far backup protection, and circuit breaker failure protection corresponding to the suspected components, analytical models of the operating states of the protection and circuit breakers under the conditions of failure to operate and maloperation are obtained.

[0036] The action state for protecting r∈R is analyzed as follows:

[0037]

[0038] The operational state of circuit breaker c∈C can be analyzed as follows:

[0039]

[0040] Combining equations 6 and 7, we obtain the action state analytical model:

[0041]

[0042] Where, d c m c Indicates refusal to move followed by accidental movement; rd r Indicates an action but also a refusal to move; Indicates that something was not moved but was moved accidentally; f r m r This indicates that there was motivation but also a misoperation; This indicates no excitation and no operation; c∈C represents the analysis of the circuit breaker's operating state, and r∈R represents the analysis of the protection's operating state.

[0043] Furthermore, the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker are as follows:

[0044] The protection r takes action (r=1), and the alarm information of its action is not missed (l r =0);

[0045] The protection r did not activate (r=0), but its alarm message was a false alarm (m). r =1).

[0046] The protection r action (c=1) is triggered, and its alarm information is not missed (l) c =0);

[0047] The protection device r did not activate (c=0), but its alarm message was a false alarm (m). c =1)

[0048] Furthermore, the parsing of alarm information for protection devices and circuit breakers includes:

[0049] The alarm information analysis models of protection and circuit breakers under the conditions of missed alarm and false alarm are obtained by analyzing the operation status of protection and circuit breakers under the conditions of missed alarm and false alarm.

[0050] The analytical expression for the alarm signal r′ of protection r is:

[0051]

[0052] w r l r Indicates missed reports and false alarms, r′l r This indicates that there were alarm messages that were missed. This indicates a false alarm without any alarm information. r This indicates a false alarm indicating a protective action. This indicates that the protection mechanism failed to activate and was not reported.

[0053] By performing an equivalent transformation on the above equation, we can obtain:

[0054]

[0055] An alarm message will be sent if no action is taken. This indicates that no alarm messages were received for the action;

[0056] further:

[0057]

[0058] Inside This means that it is equivalent to, This indicates an error message;

[0059] According to the above formula, the protection action alarm message is incorrect. r Together with its alarm information r′, it forms an explicit function of the protection action state r;

[0060] For any circuit breaker c∈C, when false alarms and missed alarms occur, constraining its contradictory logic state, the alarm information c′ that can be parsed to express its tripping state is:

[0061]

[0062] Furthermore, false alarms and missed alarms of circuit breakers are decoupled, namely:

[0063]

[0064] further:

[0065]

[0066] Furthermore, the action state timing analysis includes: performing action state timing analysis on the protection and circuit breaker to obtain the element function, state function and state change function of the protection and circuit breaker containing timing information;

[0067] Component functions:

[0068] Use s d,k This represents the state of the k-th component, where 0 indicates a normal state and 1 indicates a fault state.

[0069]

[0070] In the formula: t0 represents the time reference point, t N-1 t represents the action time of the last alarm. N Indicates the time when the fault ends, s d,k =0 or s d,k =1 indicates that the k-th component is either not faulty or has failed at time t;

[0071] State function:

[0072] Before the protection and circuit breaker operate, the previous state value is set to 0; after operation, the state value is set to 1.

[0073]

[0074]

[0075] In the formula: Corresponding to the moment of the protective action, Corresponding to the operating time of the circuit breaker, r i (t) = 0 or 1, c j (t) = 0 or 1 respectively indicates that the i-th protection or circuit breaker has not failed or has failed at time t;

[0076] State change function:

[0077] When the protection and circuit breaker operate within the fault range of the component, the state change function value is defined as 1; when the component is within the fault range, its state change function value is 0.

[0078]

[0079]

[0080] In the formula: t s t indicates the moment when the protection or circuit breaker change begins. e Indicates the moment when the protection or circuit breaker change ends.

[0081] Furthermore, the physical model for the power grid fault information is as follows:

[0082]

[0083] Furthermore, the physical model of the power grid fault information is simplified to obtain the following objective function: V(G,L,W)=V(G,E)

[0084]

[0085] in, This indicates an expectation of no action but an actual action. This indicates that the expected action was not actually performed.

[0086] The beneficial effects of this invention are as follows: The power grid fault diagnosis method based on timing and sequence information involved in this invention relates to the power grid protection rules and the 0-1 information model of the power grid, completely preserving the component states, protection, and circuit breaker operation rules of the power grid. By receiving the information model from dispatchers and starting with the parsing of the power grid model, the originally complex model is generalized, thereby improving the universality and accuracy of the cyber-physical model in power grid fault diagnosis. Subsequently, specific calculation examples are used to describe the cyber-physical model of the power grid and its diagnosis of power grid faults, thereby improving the adaptability of the cyber-physical model in actual power grids. Attached Figure Description

[0087] Figure 1 This invention provides a flowchart of various information and timing sequences for power grid fault diagnosis.

[0088] Figure 2 This is a hierarchical diagram of power grid fault information processing in this invention;

[0089] Figure 3 This is a flowchart illustrating the establishment and solution process of the fault diagnosis model for this invention. Detailed Implementation

[0090] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0091] It should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integrally formed structures. Those skilled in the art can understand the specific meaning of these terms in this patent based on the specific circumstances.

[0092] like Figure 1 , Figure 2 as well as Figure 3As shown, the power grid fault diagnosis method based on timing and timing information designed in this invention includes the following steps:

[0093] Obtain the operating status of the protection corresponding to the suspicious element and the operating status of the circuit breaker corresponding to the suspicious element; obtain the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker.

[0094] The operating status of the protection and circuit breaker is analyzed separately to obtain the operating status analysis model;

[0095] Alarm information is analyzed for both protection devices and circuit breakers to obtain an alarm information analysis model;

[0096] By combining the action state analysis model and the alarm information analysis model, a physical model of power grid fault information is constructed.

[0097] The objective function of the power grid fault information physical model is established, and the objective function is solved in combination with the power grid fault information physical model to obtain the fault diagnosis result.

[0098] In this embodiment, symbols can be defined sequentially based on the operating status and alarm information of the power grid and circuit breakers.

[0099] Specifically, the definition symbols are, in order: S, R, C, M, D, R', C', L, W, where,

[0100] S = [s1s2…s] i …s N ] indicates the state of the suspicious element, where s i =1 indicates a suspicious element s i A malfunction occurred, s i =0 indicates no fault occurred;

[0101] R = [r1r2…r] i …r Z ] indicates the protection status corresponding to the suspected component, where r i =1 indicates protection r i Action, r i =0 indicates no action was taken;

[0102] C = [c1c2…c i …c K ] indicates the status of the circuit breaker corresponding to the suspected component, where c i =1 indicates circuit breaker c i Tripping, c i =0 indicates that the circuit breaker has not tripped;

[0103] M = [M R M c ],in, and Indicates protection r i (Circuit breaker c) i Accidental movement This corresponds to no erroneous operation;

[0104] D = [D R D C ],in, and Indicates relevant protection r i (Circuit breaker c) i Refusal to move occurred. This corresponds to no failure to move.

[0105] R′=[r′1r′2…r′ z [ ] is the alarm information vector corresponding to protection R;

[0106] C′=[c′1c′2…c′ k [This is the alarm information vector corresponding to circuit breaker C;]

[0107] L = [L R ,L C ] represents the false alarm vector, where, And l r =1(l c =1) and l r =0(l c =0) respectively indicates that the protection r (circuit breaker c) has a missed alarm message and no missed alarm message;

[0108] W = [W R W C ] represents the false alarm vector for alarm information, where, And w r =1(w c =1) and w r =0(w c =0) indicates that the protection r (circuit breaker c) has a false alarm and no false alarm, respectively.

[0109] As one implementation method, the operation status analysis of the protection and circuit breaker includes operation status rule analysis and operation status timing analysis.

[0110] Specifically, the action state rule parsing includes:

[0111] The action status rules of the protection are analyzed to obtain the expected actions of the main protection, near backup protection, far backup protection and circuit breaker failure protection corresponding to the suspicious components;

[0112] The circuit breaker's operating state rules are parsed to obtain the circuit breaker's expected operation.

[0113] Specifically, the action state rule parsing includes:

[0114] The action status rules of the protection are analyzed to obtain the expected actions of the main protection, near backup protection, far backup protection and circuit breaker failure protection corresponding to the suspicious components;

[0115] The circuit breaker's operating state rules are parsed to obtain the circuit breaker's expected operation.

[0116] Preferably, the calculation process for the expected operation of the main protection, near backup protection, far backup protection, and circuit breaker failure protection corresponding to the suspected component is as follows:

[0117] Let element s d,k The main protection is r i If the suspected component s d,k Fault (s) d,k =1), then its main protection r i The action should be performed, and its expected action is... for:

[0118]

[0119] Let element s d,k Near backup protection is r j When element s d,k Fault occurred and the main protection r i When no action is taken, s d,k =1, r i =0, then the nearest backup protection r j The action should be performed, and its expected action is... It can be parsed as follows:

[0120]

[0121] Let element s d,k The remote backup protection is r l r l For s d,k And for s d,k Adjacent components within the protected area d,l Provides remote backup protection, among which,

[0122] If s d,k Fault (s) d,k =1), and its corresponding main protection r i and near backup protection r j If no action is taken, then remote backup protection will be activated. l Action is required;

[0123] If element s d,l ∈Z(rl ,s l ) fault, and r l to s l All circuit breakers p(r) on the associated path l ,s l All are closed states, when s d,k Adjacent elements d,l If a fault occurs and its associated path is connected, then the remote backup protection r l Action is required;

[0124] Therefore, the expected value of its action f rl for:

[0125]

[0126] If protect r x Action-driven circuit breaker c k If the circuit breaker trips and fails to operate, then the circuit breaker failure protection is activated. k The protection fails when it should have been activated. for:

[0127]

[0128] R indicates the status of the protection corresponding to the suspected element, and C indicates the status of the circuit breaker corresponding to the suspected element.

[0129] Preferably, the calculation process for the expected operation of the circuit breaker is as follows:

[0130] Circuit breaker c k Corresponding arbitrary protection r x Action, and cause circuit breaker c k If the circuit breaker trips, then circuit breaker c will trip at this time. k The circuit breaker should trip (c) k =1), then the expected operation f of its circuit breaker. ck Represented as:

[0131]

[0132] R indicates the status of the protection corresponding to the suspected element, and C indicates the status of the circuit breaker corresponding to the suspected element.

[0133] Furthermore, based on the expected operation of the main protection, near backup protection, far backup protection, and circuit breaker failure protection corresponding to the suspected components, analytical models of the operating states of the protection and circuit breakers under the conditions of failure to operate and maloperation are obtained.

[0134] It should be noted that there are cases of refusal to act and accidental action: refusal to act indicates an expectation of protection but no action is taken; accidental action means that no expectation of protection is expected but action is actually taken. Obviously, this is a contradictory logical state and is mutually exclusive.

[0135] The situation of "action refusal": A protective action indicates that there was an expectation of action to protect against a real action, while a protective refusal indicates that there was an expectation of action to protect against, but no actual action was taken. Obviously, this is a contradictory logical state and they are mutually exclusive.

[0136] The situation of inaction followed by malfunction: Inaction means there was no expected protection and therefore no action was taken; malfunction means the protection device actually activated despite no expected action. Clearly, this is a contradictory and mutually exclusive logical state.

[0137] Cases with incentives but also false triggers: False triggers indicate protective actions without expected value, which is obviously contradictory to protective actions with expected value, and they are mutually exclusive.

[0138] No incentive and refusal to act: Refusal to act indicates a protective expectation but no actual action, which is obviously contradictory to the lack of protective incentive and is mutually exclusive.

[0139] The action state for protecting r∈R is analyzed as follows:

[0140]

[0141] The operational state of circuit breaker c∈C can be analyzed as follows:

[0142]

[0143] Combining equations 6 and 7, we obtain the action state analytical model:

[0144]

[0145] Where, d c m c Indicates refusal to move followed by accidental movement; rd r Indicates an action but also a refusal to move; Indicates that something was not moved but was moved accidentally; f r m r This indicates that there was motivation but also a misoperation; This indicates no excitation and no operation; c∈C represents the analysis of the circuit breaker's operating state, and r∈R represents the analysis of the protection's operating state.

[0146] As one implementation method, the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker are as follows:

[0147] The protection r takes action (r=1), and the alarm information of its action is not missed (l r =0);

[0148] The protection r did not activate (r=0), but its alarm message was a false alarm (m). r =1).

[0149] The protection r action (c=1) is triggered, and its alarm information is not missed (l) c =0);

[0150] The protection device r did not activate (c=0), but its alarm message was a false alarm (m). c =1).

[0151] It should be noted that false alarms and missed alarms are contradictory logical states: a false alarm means that the protection receives an alarm message from the action dispatch center even though there is no action dispatch center; a missed alarm means that the protection performs an action but the action dispatch center does not receive an alarm message.

[0152] Alarm-Missed Report: An alarm means that the dispatch center has received an alarm message; a missed report means that the dispatch center has not received an alarm message, which is a contradictory logical state.

[0153] No alarm - false alarm: No alarm means that the dispatch center has not received alarm information; false alarm means that the dispatch center has received incorrect alarm information, which is a contradictory logical state.

[0154] Protection Action - False Alarm: This proposition means that the protection system took action but was considered a false alarm. In the definition above, a false alarm is defined as receiving an alarm signal from the protection system, but the protection system did not actually take action. Since protection action and non-action are logically mutually exclusive propositions, this is a contradictory logical state.

[0155] Protection not activated - missed alarm: When protection is activated but the dispatch center does not receive its alarm information, it is called a missed alarm, which is a contradictory logical state.

[0156] Specifically, the parsing of alarm information for protection devices and circuit breakers includes:

[0157] The alarm information analysis models of protection and circuit breakers under the conditions of missed alarm and false alarm are obtained by analyzing the operation status of protection and circuit breakers under the conditions of missed alarm and false alarm.

[0158] The analytical expression for the alarm signal r′ of protection r is:

[0159]

[0160] w r l r Indicates missed reports and false alarms, r′l r This indicates that there were alarm messages that were missed. This indicates a false alarm without any alarm information. r This indicates a false alarm indicating a protective action. This indicates that the protection mechanism failed to activate and was not reported.

[0161] By performing an equivalent transformation on the above equation, we can obtain:

[0162]

[0163] An alarm message will be sent if no action is taken. This indicates that no alarm messages were received for the action;

[0164] further:

[0165]

[0166] Inside This means that it is equivalent to, This indicates an error message;

[0167] According to the above formula, the protection action alarm message is incorrect. r Together with its alarm information r′, it forms an explicit function of the protection action state r;

[0168] For any circuit breaker c∈C, when false alarms and missed alarms occur, constraining its contradictory logic state, the alarm information c′ that can be parsed to express its tripping state is:

[0169]

[0170] Furthermore, false alarms and missed alarms of circuit breakers are decoupled, namely:

[0171]

[0172] further:

[0173]

[0174] As one implementation method, the action state timing analysis includes: performing action state timing analysis on the protection and circuit breaker to obtain the element function, state function and state change function of the protection and circuit breaker containing timing information;

[0175] Component functions:

[0176] Use s d,k This represents the state of the k-th component, where 0 indicates a normal state and 1 indicates a fault state.

[0177]

[0178] In the formula: t0 represents the time reference point, t N-1 t represents the action time of the last alarm. N Indicates the time when the fault ends, s d,k =0 or s d,k =1 indicates that the k-th component is either not faulty or has failed at time t;

[0179] State function:

[0180] Before the protection and circuit breaker operate, the previous state value is set to 0; after operation, the state value is set to 1.

[0181]

[0182]

[0183] In the formula: Corresponding to the moment of the protective action, Corresponding to the operating time of the circuit breaker, r i (t) = 0 or 1, c j (t) = 0 or 1 respectively indicates that the i-th protection or circuit breaker has not failed or has failed at time t;

[0184] State change function:

[0185] When the protection and circuit breaker operate within the fault range of the component, the state change function value is defined as 1; when the component is within the fault range, its state change function value is 0.

[0186]

[0187]

[0188] In the formula: t s t indicates the moment when the protection or circuit breaker change begins. e Indicates the moment when the protection or circuit breaker change ends.

[0189] By making full use of time-series information, the accuracy of power grid fault diagnosis can be improved, which is beneficial to the application of power grid fault diagnosis models in actual situations.

[0190] As one implementation method, by combining equations 6 and 12, as well as equations 7 and 13, the physical model of power grid fault information is obtained as follows:

[0191]

[0192] Furthermore, the physical model of the power grid fault information is simplified to obtain the following objective function: V(G,L,W)=V(G,E)

[0193]

[0194] in, This indicates an expectation of no action but an actual action. This indicates that the expected action was not actually performed.

[0195] In this embodiment, using Equation 16 as the objective function and Equations 15 and 16 as constraints, the problem of finding the optimal solution of the model can be transformed into an integer programming problem with model constraints. The constrained model is as follows:

[0196]

[0197] in, This indicates an expectation of no action but an actual action. This indicates that the expected action was not actually performed.

[0198] To solve for the objective function, this embodiment employs a model-based simulated annealing algorithm. The simulated annealing algorithm primarily accepts new solutions with a certain probability value to prevent the obtained solutions from getting trapped in local optima. Furthermore, the initial temperature and termination criterion values ​​must be appropriately chosen; otherwise, the solution speed will be slow. The solution process is as follows:

[0199] 1) Read in the highest melting temperature T max and minimum melting temperature T min The number of samples k at each melting temperature s Set T = T max .

[0200] 2) Use a pseudo-random number generation program to generate a given X = {X1, X2, ..., X...} ns A set of initial values ​​(n) s Calculate the value of E(X) (where X is the number of components).

[0201] 3) Given the number of samplings k = 1.

[0202] 4) Generate a random disturbance ΔX, and calculate E(X+ΔX) and ΔE=E(X+ΔX)-E(X).

[0203] 5) If ΔE < 0, then X is replaced by X + ΔX. If ΔE > 0, then a pseudo-random number p is generated uniformly distributed between [0,1]. If exp(-ΔE / T) ≤ ρ, then X + ΔX is replaced by X. Otherwise, S is not updated.

[0204] 6) Set k = k + 1. If k < k s (Go back to 4).

[0205] 7) Set T = T max / (1+t), if T<T min Stop after outputting the result; otherwise, return to step 3).

[0206] Here, t is a parameter that gradually increases as the annealing process progresses and can be given empirically. By setting t, the speed of the annealing process can be controlled. t can vary with temperature (T), thereby adjusting the simulation time or number of iterations in various temperature ranges.

[0207] To further verify the cyber-physical model, if T3 and B2 fail, their actions will be as follows:

[0208] The T3m protection tripped QF16, while QF14 failed to operate. Its failure protection QF14f then tripped QF12, QF13, and QF19. The B2m protection tripped QF4, QF6, QF8, and QF10. The line protection L3Rs malfunctioned, and the circuit breaker QF27 tripped.

[0209] Alarm messages for actions T3m, L3Rm, L3Rs, QF14f, QF4, QF6, QF8, QF10, QF12, QF16, QF19, and QF27 were received.

[0210] Set of suspected faulty components: There are 5 suspected faulty components in the fault area, B2, B4, T3, L2, L3, which can be represented as S = {s1, s2, ..., s5};

[0211] The circuit breaker set includes 10 circuit breakers: QF4, QF6, QF8, QF10, QF12, QF13, QF14, QF16, QF19, and QF27. This can be represented as C = {c1, c2, ..., c...} 10};

[0212] The protection device set contains 40 devices: T3m, T3p, T3s, B4m, B2m, L2Sm, L2Rm, L2Sp, L2Rp, L2Ss, L2Rs, L3Sm, L3Rm, L3Sp, L3Rp, L3Ss, L3Rs, QF4f, QF8f, QF10f, QF12f, QF14f, and QF19f. This can be represented as R = {r1, r2, ..., r...} 23}

[0213] Based on the received alarm information, it can be determined that R′={r′1,r′2,…,r′ 23}, C′={c′1, c′2,…,c′ 10}

[0214] They are: {1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0}, {1 1 1 1 1 1 01 1 1}.

[0215] The objective function is to be solved using an analytical model based on timing and timing characteristics.

[0216]

[0217] The weighting coefficients are set to: w1 = 0.75, w2 = 1.5.

[0218] Its constraints are:

[0219]

[0220] i=1,2,…,23; j=1,2,…,10

[0221] After multiple solutions, V(S,E) = 4.25, which is the optimal solution. and They are respectively:

[0222] [1,0,1,0,0],

[0223] [0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],

[0224] At this time They are respectively:

[0225] [1,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0],

[0226] [1,1,1,1,1,1,0,1,1,1],

[0227] [0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],

[0228] [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0].

[0229] The diagnosis is as follows:

[0230] Transformer T3 and bus B2 are faulty;

[0231] Protect T3m, QF14f, and L3Rs from activating;

[0232] Circuit breakers QF4, QF6, QF8, QF10, QF12, QF13, QF16, QF19, and QF27 tripped;

[0233] Protect against L3Rs malfunctions;

[0234] Circuit breaker QF14 failed to operate;

[0235] False alarms in L3Rm and missed alarms in B2m.

[0236] Comparing the diagnostic conclusion with the actual movement, it is concluded that the diagnostic conclusion is completely correct.

[0237] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A power grid fault diagnosis method based on considering timing information, characterized in that, The method comprises the following steps: obtaining the action state of the protection corresponding to the suspicious element and the action state of the circuit breaker corresponding to the suspicious element, obtaining the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker; performing action state analysis on the protection and the circuit breaker respectively to obtain an action state analysis model; performing alarm information analysis on the protection and the circuit breaker respectively to obtain an alarm information analysis model; simultaneously using the action state analysis model and the alarm information analysis model to construct a power grid fault information physical model; establishing an objective function of the power grid fault information physical model, and solving the objective function in combination with the power grid fault information physical model to obtain a fault diagnosis result; wherein the action state time sequence analysis comprises: performing action state time sequence analysis on the protection and the circuit breaker to obtain an element function, a state function and a state change function of the protection and the circuit breaker containing time sequence information; the element function: With denotes the state of the kth element, =0 denotes a normal state of the element, =1 denotes a fault state of the element, i.e. ; (Formula 15) wherein: denotes a time reference point, denotes the action time of the last alarm, denotes the end time of the fault, denotes that the k-th element is not failed or has failed at the time t; S represents the state of the protection corresponding to the suspicious element; the state function: before the protection and the circuit breaker act, the state value before is defined as 0; after acting, the state value is 1; ; (Formula 16) ; (Formula 17) In the formula: Corresponding to the moment of the protective action, Corresponding to the operating time of the circuit breaker, They represent the first A protection device or circuit breaker in The system is either not currently malfunctioning or has already experienced a malfunction. the state change function: when the action time of the protection and the circuit breaker is within the fault interval of the element, the state change function value at this time is defined as 1; within the fault interval of the element, the state change function value is 0; ; (Formula 18) ; (Formula 19) In the formulae: denotes the time at which the change of the protection or circuit breaker starts, denotes the time at which the change of the protection or circuit breaker ends. 2.The power grid fault diagnosis method based on timing information according to claim 1, characterized in that, the action state analysis of the protection and the circuit breaker comprises action state rule analysis and action state time sequence analysis. 3.The power grid fault diagnosis method based on time information according to claim 2, characterized in that, the action state rule analysis comprises: performing action state rule analysis on the protection to obtain the action expectation of the main protection, the near backup protection, the far backup protection and the circuit breaker failure protection corresponding to the suspicious element; performing action state rule analysis on the circuit breaker to obtain the action expectation of the circuit breaker.

4. The power grid fault diagnosis method based on timing information according to claim 3, characterized in that, the calculation process of the action expectation of the main protection, the near backup protection, the far backup protection and the circuit breaker failure protection corresponding to the suspicious element is as follows: Set element The main protection of , if the suspicious element Fails , its main protection Should act, its action is expected : ； (Equation 1) Set element The near backup protection for When the element Fails and the main protection Does not act, at this time , The near backup protection Should act, its action expectation Can be expressed as: ; (Formula 2) Let the component Remote backup protection for , for And for Adjacent components within the protected area Provides remote backup protection, among which, If a fault , and its corresponding primary protection and near back-up protection do not act, then the far back-up protection is to act; If the element fails, and to all breakers on the associated path are in a closed state, when the element adjacent to the element fails, and its associated path is in a connected state, then the remote back-up protection is to act; Thus, the expectation of its action Is: ； (Equation 3) If the protection The circuit breaker is actuated The circuit breaker is tripped, the circuit breaker fails The protection should act, the failure protection Is: ; (Formula 4) R represents the state of the protection corresponding to the suspicious element, and C represents the state of the circuit breaker corresponding to the suspicious element.

5. The power grid fault diagnosis method based on timing information according to claim 3, characterized in that, the calculation process of the action expectation of the circuit breaker is as follows: Circuit breaker Any protection corresponding Action, and causes the circuit breaker Trips, the circuit breaker Should trip The action of its circuit breaker is expected Is expressed as: ; (Formula 5) R represents the state of the protection corresponding to the suspicious element, and C represents the state of the circuit breaker corresponding to the suspicious element. 6.The power grid fault diagnosis method based on time information according to claim 3, wherein, obtaining the action state analysis model of the protection and the circuit breaker in the case of misoperation and misoperation according to the action expectation of the main protection, the near backup protection, the far backup protection and the circuit breaker failure protection corresponding to the suspicious element; wherein the protection action state is resolved as: ; (Formula 6) Circuit breaker the action state is analyzed as: ; (Formula 7) obtaining the action state analysis model by simultaneously using equation 6 and equation 7: ; (Formula 8) wherein, indicates a false action and a misoperation; indicates an action and a misoperation; indicates no action and a misoperation; indicates an energization and a misoperation; indicates no energization and a misoperation; indicates a breaker action state analysis, indicates a protection action state analysis. 7.The power grid fault diagnosis method based on timing information according to claim 1, wherein, the alarm information corresponding to the protection and the alarm information corresponding to the circuit breaker are as follows: protect action , and the alarm information of the action of the user equipment is not missed ; protection no action but its alarm information is false alarm ; protect action , and the alarm information of the action of the user equipment is not missed ; protection no action but its alarm information is false positive . 8.The power grid fault diagnosis method based on timing information according to claim 6, characterized in that, the alarm information analysis on the protection and the circuit breaker respectively comprises: performing misoperation and misoperation state analysis on the protection and the circuit breaker respectively to obtain the alarm information analysis model of the protection and the circuit breaker in the misoperation and misoperation state; wherein the protection action alert signal analytical expression is: ; (Formula 9) represents a false negative and a false positive, represents a false negative and an alarm, represents an alarm and a false positive, represents a protection action and a false positive, represents a protection inaction and a false negative; equivalent transformation is performed on the above equation, and the following equation can be obtained: ; (Formula 10) indicates no action with an alert message, indicates action with no alert message; further: (Formula 11) inside denotes equivalent to, denotes an error message; According to the above formula, the protection action alarm information error and its alarm information explicit function that constitutes the protection action state ; For any circuit breaker When the alarm information appears false alarm and miss, the contradictory logic state is constrained, and the alarm information expressing the tripping state can be analyzed Is: ; (Formula 12) further, the misoperation and misoperation of the circuit breaker alarm information are decoupled, that is: ; (Formula 13) further: (Formula 14). 9.The power grid fault diagnosis method based on time information according to claim 2, wherein, the power grid fault information physical model is as follows: ; (Formula 20) further, the power grid fault information physical model is simplified to obtain the following objective function: ； (Equation 21) wherein, represents desired action actual inaction; represents desired action actual inaction.

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