Generation Method of State Transition Rate Matrix for Reliability Evaluation of Power Distribution Cyber-Physical System

Abstract

The present invention discloses a method for generating a state transition rate matrix for reliability assessment of a distribution information-physical system, which relates to the technical field of distribution networks. The state transition rate matrix of the i-th component of the subsystem is preprocessed to obtain an initial state transition rate matrix; the state transition rate matrix of the (i + 1)-th component of the subsystem is preprocessed to obtain a new state transition rate matrix; the initial component state transition rate matrix and the new state transition rate matrix are processed to obtain an intermediate state transition rate matrix; when the fault state of the intermediate state transition rate matrix belongs to a high-order fault, the rows and columns representing state jumps and high-order states in the intermediate state transition rate matrix are deleted; it is judged whether i in the intermediate state transition rate matrix is less than the total number of components of the subsystem. If not, the intermediate state transition rate matrix is processed to obtain the state transition rate matrix of the subsystem. Otherwise, the previous steps are repeated until i is not less than the total number of components of the subsystem.

Description

Technical Field

[0001] The invention belongs to the technical field of distribution network, and particularly relates to a method for generating a state transition rate matrix for reliability assessment of a distribution information - physical system. Background Art

[0002] The continuous deterioration of the Earth's greenhouse effect, ecological environment and the emergence of El Niño have led to an increasingly high incidence of extreme natural disasters such as typhoons. Extreme natural disasters have caused large - scale failures of power grid facilities, and the huge economic losses caused by power outages have attracted wide attention to the disaster response ability of the power grid. Distribution lines are closely related to user loads and are an important part of the power grid. Ensuring the safety and reliability of distribution lines is a concentrated manifestation of the stable and economic operation of the entire power system. However, at the same time, the disaster response ability of distribution lines is weak, and the equipment quality of distribution grids in different places varies greatly. Therefore, it is necessary to conduct research on disaster response ability assessment technology for distribution grids, that is, reliability assessment.

[0003] Reliability assessment methods are generally divided into two types: simulation method and analytical method. The simulation method is an assessment method that uses sampling technology for all random variables involved in reliability assessment based on the Monte Carlo simulation method. It has the disadvantages of slow speed, long calculation time, and poor convergence performance. The analytical method enumerates each fault of the power grid, obtains the probability of each situation occurring and the resulting consequences, and thus calculates the reliability index of the power grid. It has the advantages of clear physical concepts, fast calculation speed, and accurate results. Traditional distribution network reliability assessment assumes that the communication system is completely reliable, but in fact, the reliability of the communication system will affect the reliability of the distribution network. Assuming that the distribution network communication system is completely reliable will inevitably lead to an overly optimistic assessment of the system reliability index.

[0004] Currently, the reliability assessment of distribution information - physical systems (CPDS) has been studied at home and abroad. Representative ones are: 1) Divide the reliability of the information system of the distribution network into topological reliability, delay reliability, and error - code reliability, and combine the Monte Carlo simulation method to evaluate the reliability of CPDS. 2) Use frequency - domain to time - domain transformation to evaluate the reliability of the information system, and use a method combining the equivalent method and the minimum path method to model the physical system of the distribution network. 3) Establish a three - layer continuous - time Markov chain (CTMC) model, and based on this, use the analytical method to obtain the reliability of the distribution network. Among them, method 3 has a short solution time and a fast convergence speed. However, currently, this method can only be applied to systems with a small number of components and cannot be directly used to obtain the reliability of the distribution network. Summary of the Invention

[0005] The purpose of the invention is to provide a method for generating a state transition rate matrix for reliability assessment of a distribution information - physical system, so that the reliability assessment method based on the three - layer CTMC can be applied to the distribution network.

[0006] To achieve the above object, the present invention provides a method for generating a state transition rate matrix for reliability evaluation of a distribution information - physical system, including:

[0007] Generating a state transition rate matrix of components of a subsystem in the distribution information - physical system according to the original data of the distribution network;

[0008] Pre - processing the state transition rate matrix of the i - th component of the subsystem to obtain an initial state transition rate matrix; pre - processing the state transition rate matrix of the (i + 1) - th component of the subsystem to obtain a new state transition rate matrix; taking the Kronecker product of the initial state transition rate matrix and the new state transition rate matrix to obtain an intermediate state transition rate matrix of the subsystem;

[0009] Judging whether the fault state of the intermediate state transition rate matrix belongs to a high - order fault. If so, deleting the rows and columns representing state jumps and high - order states in the intermediate state transition rate matrix; otherwise, no processing is required and proceed to the next step;

[0010] Judging whether the number of components i in the intermediate state transition rate matrix is less than the total number of components of the subsystem. If not, processing the intermediate state transition rate matrix to obtain the state transition rate matrix of the subsystem; otherwise, repeating the previous step until i is not less than the total number of components of the subsystem.

[0011] Preferably, repeating the method for generating the state transition rate matrix for reliability evaluation of the distribution information - physical system to obtain the state transition rate matrices of all subsystems in the distribution information - physical system.

[0012] Preferably, the distribution information - physical system includes three systems: a physical subsystem, a network subsystem, and a decision - making subsystem.

[0013] Preferably, before judging whether the fault state of the intermediate state transition rate matrix belongs to a high - order fault, it further includes:

[0014] Judging whether the subsystem is a physical subsystem. When the subsystem is a physical subsystem, changing all elements representing state jumps in the intermediate state transition rate matrix to 0; otherwise, no processing is required.

[0015] Preferably, the pre - processing is: changing the diagonal elements of the state transition rate matrix to 1.

[0016] Preferably, the pre - processing of the state transition rate matrix of the i - th component of the subsystem starts from the first component.

[0017] Preferably, to determine whether the fault state of the intermediate state transition rate matrix belongs to a high-order fault, it specifically includes: determining the number of faulty components in the intermediate state transition rate matrix. When the number of faulty components is greater than 2, the fault state of the intermediate state transition rate matrix belongs to a high-order fault.

[0018] Preferably, perform diagonal value processing on the intermediate state transition rate matrix to obtain the state transition rate matrix of the subsystem.

[0019] Preferably, the diagonal value processing includes: changing the value of the diagonal element in each row of the intermediate state transition rate matrix to the opposite of the sum of the other elements in that row.

[0020] Preferably, the expression for changing the value of the diagonal element in each row of the intermediate state transition rate matrix to the opposite of the sum of the other elements in that row is:

[0021]

[0022] In the above formula, q ij is an element in the intermediate state transition rate matrix, and q ii is an element in the state transition rate matrix of the system.

[0023] Compared with the existing technologies, the present invention has the following beneficial effects:

[0024] 1. In the method for generating the state transition rate matrix for reliability assessment of the distribution information-physical system in the present invention, the state transition rate matrix of the components of the subsystem in the distribution information-physical system is generated according to the original data of the distribution network; preprocess the state transition rate matrix of the i-th component of the subsystem to obtain the initial state transition rate matrix; preprocess the state transition rate matrix of the (i + 1)-th component of the subsystem to obtain a new state transition rate matrix; perform the Kronecker product of the initial state transition rate matrix and the new state transition rate matrix to obtain the intermediate state transition rate matrix of the subsystem; determine whether the fault state of the intermediate state transition rate matrix belongs to a high-order fault. If so, delete the rows and columns representing state jumps and high-order states in the intermediate state transition rate matrix. Otherwise, no processing is required and proceed to the next step; determine whether the number of components i in the intermediate state transition rate matrix is less than the total number of components of the subsystem. If not, process the intermediate state transition rate matrix to obtain the state transition rate matrix of the subsystem. Otherwise, repeat the previous step until i is not less than the total number of components of the subsystem to obtain the state transition rate matrix of the entire subsystem. The method of the present invention is the premise for applying the reliability assessment method based on CTMC to CPDS.

[0025] 2. By repeating the method for generating the state transition rate matrix of the reliability assessment of the distribution cyber-physical system, the state transition rate matrices of all subsystems in the distribution cyber-physical system can be obtained, and the state transition rate matrices of all subsystems in the entire distribution cyber-physical system can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the present invention, the accompanying drawings required for the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only one embodiment of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0027] Figure 1 is a flowchart of a method for generating a state transition rate matrix for reliability assessment of a distribution cyber-physical system of the present invention;

[0028] Figure 2 is a schematic structural diagram of the CPDS of the present invention;

[0029] Figure 3 is a topological diagram of the CPDS of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0031] In the description of the present invention, the meaning of several is one or more, the meaning of multiple is two or more, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If there is a description of the terms "first", "second", "third", etc., it is only for the purpose of description and distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0032] The method for generating the state transition rate matrix for reliability assessment of the distribution cyber-physical system includes the following steps:

[0033] Step 1: Generate the state transition rate matrix of the components of the subsystems in the distribution cyber-physical system according to the original data of the distribution network;

[0034] Step 2: Preprocess the state transition rate matrix of the i-th component (i = 1, 2, …, n - 1, where n is the total number of components in the subsystem) of the subsystem to obtain the initial state transition rate matrix; preprocess the state transition rate matrix of the (i + 1)-th component of the subsystem to obtain a new state transition rate matrix; perform the Kronecker product of the initial state transition rate matrix and the new state transition rate matrix to obtain the intermediate state transition rate matrix of the subsystem;

[0035] Step 3: Determine whether the fault state of the intermediate state transition rate matrix belongs to a high-order fault. If so, delete the rows and columns representing state jumps and high-order states in the intermediate state transition rate matrix. Otherwise, no processing is required and proceed to the next step;

[0036] Step 4: Determine whether the number of components i of the state transition rate matrix obtained in Step 3 is less than the total number of components in the subsystem. If not, perform diagonal value processing on the state transition matrix obtained in Step 3 to obtain the state transition rate matrix of the system. Otherwise, repeat Steps 2 - 4 until i is not less than the total number of components in the subsystem, that is, until the state transitions of all components of the subsystem are processed, ensuring the accuracy of the system state transition rate matrix.

[0037] Step 5: Repeat the method for generating the state transition rate matrix for the reliability assessment of the power distribution cyber-physical system, that is, repeat Steps 1 - 4, to obtain the state transition rate matrices of all subsystems in the power distribution cyber-physical system.

[0038] Among them, the power distribution cyber-physical system includes three systems: a physical subsystem, a network subsystem, and a decision-making subsystem.

[0039] In addition, before determining whether the fault state of the intermediate state transition rate matrix belongs to a high-order fault in Step 3, it also includes:

[0040] Determine whether the subsystem is a physical subsystem. When the subsystem is a physical subsystem, change all elements representing state jumps in the intermediate state transition rate matrix to 0. Otherwise, no processing is required.

[0041] In Step 2, the preprocessing is: changing the diagonal elements of the state transition rate matrix to 1.

[0042] In Step 2, the preprocessing of the state transition rate matrix of the i-th component of the subsystem starts from the first component.

[0043] In step 3, it is determined whether the fault state of the intermediate state transition rate matrix belongs to a high-order fault, specifically including: determining the number of faulty components in the intermediate state transition rate matrix. When the number of faulty components is greater than 2, the fault state of the intermediate state transition rate matrix belongs to a high-order fault. Delete the rows and columns representing state jumps and high-order states in the intermediate state transition rate matrix to obtain a state transition rate matrix without high-order fault states.

[0044] In step 4, the diagonal value processing of the state transition matrix obtained in step 3 includes: changing the value of the diagonal element of each row in the state transition matrix obtained in step 3 to the negative of the sum of the other elements in that row, and its expression is:

[0045]

[0046] In the above formula, q ij is an element in the state transition matrix obtained in step 3, and q ii is an element in the state transition rate matrix of the system.

[0047] One embodiment is as Figure 1 shown. The method for generating the state transition rate matrix for the reliability assessment of the distribution cyber-physical system includes the following steps:

[0048] S1. Read the original data of the distribution network. The original data of the distribution network includes: the topology diagram of the distribution network and the failure rate and repair time of the components that make up the distribution network;

[0049] S2. Generate the state transition rate matrix of each component in each subsystem in the CPDS system (distribution cyber-physical system) according to the original data of the distribution network. Here, the physical subsystem is taken as an example;

[0050] S3. Let i = 1. Change the diagonal element of the state transition rate matrix Q1 of the first component of the physical subsystem to 1, and let the initial state transition rate matrix Q old(1) = Q1;

[0051] S4. Increase the value of i by 1;

[0052] S5. Change the diagonal element of the state transition rate matrix Q i of the i-th component of the physical subsystem to 1, and let the new state transition rate matrix Q new = Q i ;

[0053] S6. Perform the Kronecker product on the initial state transition rate matrix Q old and the new state transition rate matrix Q new to obtain the intermediate state transition rate matrix of the physical subsystem That is

[0054] S7. Determine whether the calculated subsystem is a physical subsystem. If the calculated subsystem is the state transition rate matrix of a physical subsystem, directly jump to S8; otherwise, jump to S9. In this embodiment, a physical subsystem is taken as an example. Therefore, it needs to be processed through step S8.

[0055] S8. Set all the elements representing state jumps in the intermediate state transition rate matrix Q of the physical subsystem obtained in step S6 old(2) to 0, obtaining a state transition rate matrix Q old(2) ' with zero state jump elements.

[0056] S9. Determine whether the fault state of the state transition rate matrix Q old(2) ' with zero state jump elements obtained in step S8 belongs to a high-order fault. When the fault state of the state transition rate matrix Q old(2) ' belongs to a high-order fault, delete all the rows and columns representing high-order states in the state transition rate matrix Q old(2) ', obtaining a state transition rate matrix Q old(2) " without high-order fault states. Otherwise, no processing is required and proceed to the next step.

[0057] Determine whether the fault state of the state transition rate matrix Q old(2) ' belongs to a high-order fault, specifically including: determining the number of faulty components in the state transition rate matrix Q old(2) '. When the number of faulty components is greater than 2, the fault state of the state transition rate matrix Q old(2) ' belongs to a high-order fault.

[0058] S10. Determine whether the i in the state transition rate matrix Q old(2) " without high-order fault states obtained in step S9 is less than the total number n of physical subsystem components. If so, return to S4; otherwise, use the state transition rate matrix Q old(2) " without high-order fault states as the initial state transition rate matrix of the system and jump to S11.

[0059] S11. Change the value of each diagonal element in the initial state transition rate matrix Q old(2) " of the system obtained in step S9 to the negative of the sum of the other elements in that row, obtaining the final state transition rate matrix Q old(n) , where changing the value of the diagonal element to the negative of the sum of the other elements in that row is:

[0060]

[0061] In the above formula, q ii , q ij are all elements in the system state transition matrix Q old(n) after deleting data.

[0062] That is, Q obtained through step S11 old(n) is the state transition rate matrix of a subsystem;

[0063] S12. Repeat steps S2 - S11 to obtain the state transition rate matrices of all subsystems of the power distribution cyber - physical system.

[0064] The above - mentioned method for generating the state transition rate matrix for the reliability assessment of the power distribution cyber - physical system multiplies the state transition rate matrices of each component in the power distribution cyber - physical system pairwise by the Kronecker product to obtain the state transition rate matrix of the entire system. This method is the premise for applying the reliability assessment method based on the Markov chain CTMC to the power distribution cyber - physical system CPDS.

[0065] Next, a more detailed description of the method for generating the state transition rate matrix for the reliability assessment of a power distribution cyber - physical system in this embodiment is given to enable those skilled in the art to better understand the present invention:

[0066] Figure 2 The structure of the CPDS is shown. Specifically, in step S1, the original data of the power distribution network includes: the topology diagram of the power distribution network and the failure rates and repair times of the components constituting the power distribution network. Here, a three - component physical subsystem is taken as an example, and the failure order is considered up to the second - order failure (the failure order is the number of failed components).

[0067] In step S2, the state transition rate matrix Q of the i - th component in the physical subsystem i is:

[0068]

[0069] In the above formula, λ i is the failure rate of the i - th component in the system, and μ i is the repair rate of the i - th component in the system. The repair rate is the reciprocal of the repair time.

[0070] In step S3, the initial state transition rate matrix Q obtained after pre - processing old(1) is:

[0071]

[0072] In the above formula, the initial state transition rate matrix Q old(1) is used to store the state transition rate matrix of the entire system. λ1 is the failure rate of the first component in the system, and μ1 is the repair rate of the first component in the system.

[0073] In step S4, after processing this step, i = 2 at this time.

[0074] In step S5, the new state transition rate matrix Q obtained after preprocessing step S4 new is as follows:

[0075]

[0076] In the above formula, λ2 is the failure rate of the second component in the system, and μ2 is the repair rate of the second component in the system.

[0077] In step S6, the matrix Q obtained in step S3 old(1) and the matrix Q obtained in step S5 new are subjected to the Kronecker product, and the intermediate state transition rate matrix Q of the physical subsystem old(2) is as follows:

[0078]

[0079] In step S7, since the intermediate state transition rate matrix of the physical subsystem is calculated, S8 cannot be skipped.

[0080] In step S8, it can be seen that the elements Q old(2) (1, 4), Q old(2) (2, 3), Q old(2) (3, 2) and Q old(2) (4, 1) of the Q obtained in step S6 represent state jumps. For example, the element Q old(2) (1, 4) represents that this two-component system changes from both components working normally to both components failing, and Q old(2) (4, 1) represents that this two-component system changes from both components failing to both components working normally. After changing these elements to 0, the state transition rate matrix Q old(2) ' is as follows:

[0081]

[0082] In step S9, the elements in the first row of the matrix Q old(2) ' obtained in step S8 represent that the system changes from the state of no component failure (working normally) to various failure states, and the elements in the first column represent that the system changes from various component failure states to the working normally state; and since the fourth row and the fourth column represent the state where both components of the system fail, which belongs to the second-order failure. In this example, the failure order is considered up to the second order at most, and at this time, the state of the second-order failure does not belong to the "higher-order failure" and no operation is required for the time being.

[0083] In step S10, at this time i = 2 is less than the total number of components n = 3, and the steps of S4 - S9 need to be performed again. After completing step S7, the state transition rate matrix Q old(3) is as follows:

[0084]

[0085] In the above formula, λ3 is the failure rate of the third component in the system, and μ3 is the repair rate of the third component in the system.

[0086] After step S8 deletes the elements with state jumps, the state transition rate matrix Q with state jump elements being zero old(3) is:

[0087]

[0088] After step S9 deletes the rows and columns representing the third-order faults, the state transition rate matrix Q without high-order fault states is obtained old(3) is:

[0089]

[0090] At this time, i = 3, which is equal to the total number of components, and jumps to step S11.

[0091] In step S11, after the operations of the above steps, it is the state transition rate matrix of the desired subsystem, and the state transition rate matrix Q of the desired subsystem old(n) is:

[0092]

[0093] That is, the state transition rate matrix of the three-component physical subsystem is obtained.

[0094] The following further illustrates the calculation of the state transition rate matrix of CPDS in combination with the specific parameter data of the operation of specific distribution network components. The present invention uses a Python program to write the state transition rate matrix algorithm of CPDS.

[0095] The calculation process of the state transition rate matrix of CPDS in this embodiment is as Figure 1 shown. The topological diagrams of the physical subsystem and the network subsystem in the embodiment are as Figure 3 shown. The parameters of the physical subsystem in the embodiment are shown in Table 1, and the parameters of the information subsystem are shown in Table 2. There are 250 users at load point A, 100 users at load point B, and 50 users at load point C. The isolation switching time of the sectionalizing switch is 0.5 hours each time, and the switching time of the alternative power supply is 1.0 hour. This embodiment only takes the calculation of the state transition rate matrix of the physical subsystem as an example, and the physical subsystem only considers first-order faults and does not consider state jumps.

[0096] Table 1 Parameters of the physical subsystem

[0097]

[0098] Table 2 Parameters of the information subsystem

[0099]

[0100] In step S1, reading the original data of the distribution network includes: the topological diagrams of the physical subsystem and the information subsystem of the distribution network, as well as the failure rates and repair times of the components that make up the distribution network.

[0101] In step S2, in the physical subsystem, the failure rates and repair rates of the components appearing in Table 1 cannot be ignored, so the state transition rate matrix of such components is not a zero matrix. For example, the state transition rate matrix of feeder M1 is:

[0102]

[0103] For the components not appearing in Table 1, such as circuit breakers and disconnectors, it is considered that such components do not fail. For example, the state transition rate matrix of a circuit breaker is:

[0104]

[0105] After calculation, in step S11, the initial state transition rate matrix of the physical subsystem is:

[0106] Q PH =

[0107] [-2.1 0. 0. 0. 0.25 0.5 0.75 0. 0. 0. 0. 0. 0. 0.1 0.3 0.2 0.],

[0108] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0109] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0110] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0111] [8760. 0. 0. 0. -8760. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0112] [8760. 0. 0. 0. 0. -8760. 0. 0. 0. 0.,0. 0. 0. 0. 0. 0. 0.],

[0113] [8760. 0. 0. 0. 0. 0. -8760. 0. 0. 0.,0. 0. 0. 0. 0. 0. 0.],

[0114] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0115] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0116] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0117] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0118] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0119] [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.],

[0120] [2920. 0. 0. 0. 0. 0. 0. 0. 0. 0.,0. 0. 0.-2920. 0. 0. 0.],

[0121] [2920. 0. 0. 0. 0. 0. 0. 0. 0. 0.,0. 0. 0. 0.-2920. 0. 0.],

[0122] [2920. 0. 0. 0. 0. 0. 0. 0. 0. 0.,0. 0. 0. 0. 0.-2920. 0.], [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]

[0125] For the matrix Q PH change the values of the diagonal elements of each row to the negative of the sum of the other elements in that row to obtain the state transition rate matrix of the physical subsystem:

[0126] ​

[0127] In summary, the method for generating the state transition rate matrix of the distribution cyber-physical system reliability evaluation provided can generate the state transition rate matrices of each subsystem of the distribution cyber-physical system, and the calculation speed can be effectively improved through the present invention. The method of the present invention is a prerequisite for applying the reliability evaluation method based on CTMC to CPDS.

[0128] The foregoing description of specific exemplary embodiments of the present invention is for the purposes of illustration and exemplification. These descriptions are not intended to limit the present invention to the precise forms disclosed, and obviously, many changes and variations can be made in light of the above teachings. Although embodiments of the present invention have been shown and described, the specific embodiments are merely interpretations of the present invention and do not limit the invention. The specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical applications, so that those skilled in the art can, after reading this specification, make modifications, substitutions, variations, and various different selections and changes that do not make a creative contribution to the embodiments as needed, but as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A method for generating a state transition rate matrix for reliability assessment of a distribution cyber-physical system, characterized in that Including: Generating a state transition rate matrix of components of a subsystem in a power distribution information - physical system according to the original data of the distribution network; Pre - processing the state transition rate matrix of the i - th component of the subsystem to obtain an initial state transition rate matrix; Pre - processing the state transition rate matrix of the (i + 1)-th component of the subsystem to obtain a new state transition rate matrix; Performing a Kronecker product of the initial state transition rate matrix and the new state transition rate matrix to obtain an intermediate state transition rate matrix of the subsystem; Judging whether the fault state of the intermediate state transition rate matrix belongs to a high - order fault. If so, deleting the rows and columns representing state jumps and high - order states in the intermediate state transition rate matrix; otherwise, no processing is required and proceed to the next step; Judging whether the number of components i in the intermediate state transition rate matrix is less than the total number of components of the subsystem. If not, processing the intermediate state transition rate matrix to obtain the state transition rate matrix of the subsystem; otherwise, repeating the previous step until i is not less than the total number of components of the subsystem.

2. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 1, wherein Repeating the method for generating the state transition rate matrix for the reliability assessment of the power distribution information - physical system to obtain the state transition rate matrices of all subsystems in the power distribution information - physical system.

3. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 1, wherein The power distribution information - physical system includes three systems: a physical subsystem, a network subsystem, and a decision - making subsystem.

4. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 1, wherein Before judging whether the fault state of the intermediate state transition rate matrix belongs to a high - order fault, it further includes: Judging whether the subsystem is a physical subsystem. When the subsystem is a physical subsystem, changing all elements representing state jumps in the intermediate state transition rate matrix to 0; otherwise, no processing is required.

5. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 1, wherein The pre - processing is: changing the diagonal elements of the state transition rate matrix to 1.

6. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 1, wherein The pre - processing of the state transition rate matrix of the i - th component of the subsystem starts from the first component.

7. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 1, wherein Judging whether the fault state of the intermediate state transition rate matrix belongs to a high - order fault specifically includes: judging the number of faulty components in the intermediate state transition rate matrix. When the number of faulty components is greater than 2, the fault state of the intermediate state transition rate matrix belongs to a high - order fault.

8. According to the method for generating the state transition rate matrix for the reliability assessment of the power distribution information - physical system according to claim 1, performing diagonal value processing on the intermediate state transition rate matrix to obtain the state transition rate matrix of the subsystem.

9. The method for generating the state transition rate matrix of the reliability evaluation of the distribution information-physical system according to claim 8, characterized in that, The diagonal value processing includes: changing the values of the diagonal elements in each row of the intermediate state transition rate matrix to the negative of the sum of the other elements in that row.

10. The method for generating the state transition rate matrix of the reliability evaluation of the power distribution cyber-physical system according to claim 9, wherein The expression for changing the values of the diagonal elements in each row of the intermediate state transition rate matrix to the negative of the sum of the other elements in that row is: In the above formula, q ij is an element in the intermediate state transition rate matrix, and q ii is an element in the state transition rate matrix of the system.

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