System fault tolerance estimation method based on system component structure

Abstract

The invention relates to a system fault tolerance estimation method based on a system component structure, belongs to the technical field of fault tolerance analysis, and solves the problems that in the prior art, a systematic evaluation method for fault tolerance is lacked, and an evaluation result is inaccurate. The system fault tolerance estimation method comprises the following specific steps: step 1, constructing a component structure-oriented system directed graph; and 2, based on the component structure-oriented system directed graph, the fault tolerance of the system structure is obtained, the system fault tolerance estimation method quantifies the influence of component errors on the fault tolerance of the system from the perspective of functional logic, and the fault tolerance of the system can be evaluated more accurately.

Description

Technical Field

[0001] This invention belongs to the field of fault tolerance analysis technology, specifically relating to a system fault tolerance estimation method based on system component structure. More particularly, it relates to a system fault tolerance estimation method based on the system component structure of a solar cell array. Background Technology

[0002] With technological advancements and increasing system complexity, high reliability and safety have become critical requirements in aerospace, battery, energy, and transportation industries. In these fields, the failure of any single component can lead to the loss of entire system functionality, causing catastrophic consequences. Ensuring continued system operation even when components fail is a key challenge in reliability engineering. The ability of a system to continue functioning despite component failures is known as its fault tolerance.

[0003] However, existing fault-tolerant technologies have some shortcomings. First, traditional fault prediction methods mainly focus on estimating the failure probability or predicting the remaining life of individual components, while performance prediction techniques focus on monitoring the degree to which key parameters deviate from normal thresholds. Although these two types of technologies can indirectly reflect the quality of a system to some extent, they cannot directly evaluate the system's fault tolerance capability, making it difficult to guide improvements in fault-tolerant design. On the other hand, existing fault-tolerant technologies lack a systematic quantitative evaluation system for fault tolerance capability, making them difficult to implement in engineering practice. Essentially, existing methodologies fail to establish a mapping relationship from micro-level fault characteristics to macro-level fault tolerance capability, and even more so, lack an evaluation model for the dynamic evolution of system-level fault tolerance capability. Summary of the Invention

[0004] In view of the above problems, the present invention provides a system fault tolerance estimation method based on system component structure, which solves the problems of lack of systematic evaluation method for fault tolerance capability and inaccurate evaluation results in the prior art.

[0005] This invention provides a system fault tolerance estimation method based on system component structure, the specific steps of which are as follows: Step 1. Construct a directed graph of the system based on a component-oriented architecture; The system includes a single-input single-output (SISO) system and a multiple-input multiple-output (MIMO) system; Step 2. Obtain the system structural fault tolerance based on the directed graph of the component-oriented system structure; For a single-input single-output system, based on the directed graph of the system, the redundancy between the starting point and the ending point of a single directed graph is obtained, and the redundancy is normalized to obtain the system structural fault tolerance. For a multiple-input multiple-output (MIMO) system, based on the directed graph of the MIMO system, the redundancy between multiple starting points and multiple ending points of the directed graph is obtained. This redundancy is used as an element of the fault tolerance matrix of the MIMO system. Valid start-end node pairs for the system's functional path are then selected, and the average structural fault tolerance of the valid start-end node pairs is used as the structural fault tolerance of the MIMO system.

[0006] Optionally, the expression for the structural fault tolerance of a single-input single-output (SISO) system is:

[0007] in, Indicates the system in state Structural tolerance; Indicates the system in state Lower system directed graph From the starting point s To the finish line e The total number of all unique function paths; Indicates the system in state The system is a directed graph; This indicates the system in its initial state. The system is a directed graph; Indicates the system's degradation time state of time The following is a directed graph of component structure.

[0008] Optionally, the structural fault tolerance of a multiple-input multiple-output (MIMO) system is expressed as:

[0009]

[0010] in, P This represents the structural tolerance matrix of the system; Indicates the first i The starting point and the first directed graph k The structural tolerance of the start and end nodes of a directed graph. , , m Indicates the total number of starting points. n Indicates the total number at the finish line; Indicates the first i A starting point of a directed graph, Indicates the first k The endpoint of a directed graph.

[0011] Optionally, a Boolean matrix can be used as the filtering matrix to filter and correct the redundancy matrix to obtain an effective redundancy matrix.

[0012] Optionally, the effective redundancy matrix U The expression is:

[0013] Where A represents a Boolean matrix, ; Indicates the first i The starting point and the first directed graph k A pair of start and end nodes for the endpoint of a directed graph; No. i The starting point and the first directed graph k Redundancy of valid start and end node pairs at the endpoint of a directed graph. satisfy:

[0014] in, This represents an invalid value.

[0015] Optionally, the structural tolerance of the multi-input multi-output system is obtained based on the effective start-end node pairs obtained by filtering and correcting the tolerance matrix. The expression is: .

[0016] Optionally, it also includes step 3, which quantifies the overall fault tolerance of the system based on the fault tolerance at the system structure level and the fault tolerance at the professional performance level.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: (1) The system fault tolerance estimation method of the present invention solves the problem of the lack of a quantitative evaluation system for fault tolerance capability, and has reference value for the establishment of an evaluation system for fault-tolerant systems; (2) The system fault tolerance estimation method of the present invention quantifies the impact of component errors on system fault tolerance from the perspective of functional logic, and can more accurately assess system fault tolerance. Attached Figure Description

[0018] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0019] Figure 1 This is a flowchart of the system fault tolerance estimation method based on system component structure according to the present invention. Detailed Implementation

[0020] To better understand the above-described objectives, features, and advantages of the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other. Furthermore, the present invention can be implemented in other ways different from those described herein; therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0021] A specific embodiment of the present invention, such as Figure 1 A system fault tolerance estimation method based on system component structure is disclosed, and the specific steps are as follows: Step 1. Construct a directed graph of the system based on a component-oriented architecture.

[0022] Specifically, the system includes a single-input single-output (SISO) system and a multiple-input multiple-output (MIMO) system.

[0023] For a single-input single-output (SSO) system, its directed graph has only one start point and one end point. The directed graph of a SSO system is as follows:

[0024] in, V Represents the set of nodes in a directed graph. , s The starting point of the directed graph represents the system's input. e The endpoint of the directed graph represents the system's output; For components Functional components; E This represents the set of edges in a directed graph.

[0025] It is understandable that the starting point of a directed graph is the first functional step that the system needs to go through to complete its function; the focus of a directed graph is the system's output.

[0026] For a multiple-input multiple-output system, the expression for its directed graph is:

[0027] in, , Represents the set of starting points of a directed graph. Represents the set of endpoints in a directed graph. , , Indicates the first m A starting point of a directed graph, Indicates the first n A directed graph endpoint; E This represents the set of edges in a directed graph.

[0028] Furthermore,E The elements in the text represent the interaction relationships between components, for example, the flow of matter, energy, and information between various functional links.

[0029] It is understandable that a function requires multiple functional components, and the function can only be realized when all functional components are complete.

[0030] Step 2. Obtain the system structure tolerance based on the directed graph of the component-oriented system structure.

[0031] Specifically, for a single-input single-output system, based on the directed graph of the system, the redundancy between the starting point and the ending point is obtained, the redundancy is normalized, and the fault tolerance of the system structure is obtained.

[0032] Furthermore, the redundancy between the start and end points refers to the redundant functional paths between the start and end points.

[0033] Furthermore, the structural tolerance of the system is obtained, expressed as:

[0034] in, Indicates the system in state Structural tolerance; Indicates the system in state Lower system directed graph From the starting point s To the finish line e The total number of all unique function paths; Indicates the system in state The system is a directed graph; This indicates the system in its initial state. The system is a directed graph; Indicates the system's degradation time state of time The following is a directed graph of component structure.

[0035] Understandably, when When this occurs, it means that the system initially lacks redundancy and therefore does not possess structural fault tolerance. ;and This indicates that the system currently does not have a functional path and cannot perform the function. In this case, the system's structural fault tolerance is 0.

[0036] Specifically, for a multiple-input multiple-output (MIMO) system, based on the directed graph of the MIMO system, the redundancy between the start and end points is obtained and used as an element of the MIMO system's fault tolerance matrix. Then, the effective start-end node pairs of the system's functional path are selected, and finally, the average structural fault tolerance of the effective start-end node pairs is used as the system fault tolerance of the MIMO system.

[0037] Furthermore, the structural tolerance of the system is obtained, expressed as:

[0038]

[0039] in, P This represents the structural tolerance matrix of the system; Indicates the first i The starting point and the first directed graph k The structural tolerance of the start and end nodes of a directed graph. , , m This represents the total number of starting points in a directed graph. n This represents the total number of endpoints in a directed graph; Indicates the first i A starting point of a directed graph, Indicates the first k The endpoint of a directed graph.

[0040] Furthermore, in MIMO systems, There are two scenarios: one is that the start and end node pairs of the directed graph are valid but there is no functional path, resulting in system failure; the other is that the start and end node pairs of the directed graph are invalid, and the lack of a functional path does not affect the system's functionality. For start and end node pairs that do not meet the requirements (i.e., the aforementioned system failure and invalid states), a Boolean matrix is ​​used. The redundancy matrix is ​​used as a filtering matrix to filter and correct it, and its first... i The starting point and the first directed graph k The start and end nodes of a directed graph. Satisfy: When the start and end nodes are paired When it is the start and end point of the system's functional path, A value of 1 indicates a valid start-end node pair; when the start-end node pair... When it is not the start or end point of the system's functional implementation path, A value of 0 indicates an invalid start-end node pair.

[0041] Based on the Boolean matrix, obtain the effective redundancy matrix. U , , No. i The starting point and the first directed graphk Redundancy of valid start and end node pairs at the endpoint of a directed graph. satisfy:

[0042] in, This represents an invalid value, which is not included in the calculation. All addition and multiplication calculations return the original value, that is, for ,have , ; This indicates the value used in the calculation. This process distinguishes between invalid and valid start / endpoints, thus accurately quantifying the overall structural fault tolerance of the system.

[0043] This invention, through this process, can distinguish between invalid and valid start and end points, thereby accurately quantifying the overall structural fault tolerance capability of the system.

[0044] Furthermore, after filtering and correcting the tolerance matrix, the average structural tolerance of effective start-end node pairs is obtained based on the redundancy of the multi-input multi-output system. The expression is:

[0045] It is understandable that when the fault tolerance between any valid start-end pair is greater than 0, it means that there are redundant functional paths between all inputs and outputs of the system at this moment. The average value of the structural fault tolerance of each valid node pair is used as the redundancy measure of the system. When there is no redundancy in the number of functional paths between a certain pair of valid start-end pairs, it is considered that the system no longer has structural fault tolerance, that is, the structural fault tolerance of the system is 0.

[0046] Step 3. Based on the system structure fault tolerance and professional performance fault tolerance, obtain the overall fault tolerance capability of the system, expressed as:

[0047] in, Indicates degradation time The overall fault tolerance of the system Indicates degradation time The corresponding system state at that time The system's structural fault tolerance. Indicates degradation time The system is in state The system's internal dependent variables and external variables The tolerance for errors in professional performance.

[0048] Understandably, internal variables are variables that affect the system and are related to the system itself, such as the system's design parameters, materials, and dimensions; external variables are factors outside the system that affect the system, such as ambient temperature, humidity, and vibration.

[0049] Furthermore, the specific steps of the method for estimating the professional performance tolerance are as follows: Step 11. Based on the interdisciplinary equation, degradation equation, and margin equation, construct the professional performance margin model of the system, expressed as:

[0050] in, For return / exchange time The professional performance margin of the timing system; It is an internal variable of the system; Indicates the system status; It is an external variable of the system.

[0051] For example, the internal variables are the system's design parameters, material properties, or geometric dimensions; the external variables are temperature, vibration, or voltage and current.

[0052] Furthermore, the interdisciplinary equation is:

[0053] in, P These are the system's performance parameters.

[0054] For example, for a mobile phone, the system's performance parameters include screen refresh rate, battery capacity, etc.

[0055] Furthermore, the degradation equation is:

[0056] in, P ( ) indicates the time of degradation System performance.

[0057] Furthermore, the margin equation is:

[0058] in, P th A threshold representing system performance.

[0059] Step 21. Based on the system's professional performance margin When retrieving the first pass, the expression is:

[0060] in, This indicates the moment when the system's performance margin first becomes less than 0; Indicates the infimum; Represent the set of positive real numbers; Indicates degradation time The system's professional performance margin.

[0061] Furthermore, based on a given discrete degradation time vector The transformation formula for obtaining the first penetration is:

[0062] in, Indicates the first j When a degeneration occurs The system's professional performance margin; Indicates the first j +1 degeneration time The system's professional performance margin; Understandably, First Passage Time refers to the time when a system or process first reaches a specific state or goal.

[0063] Step 31. Based on the reliable degradation time range of the system determined at the first crossing. To obtain the system's professional performance tolerance The expression is:

[0064] in, Indicates degradation time The professional performance tolerance of the time system; Indicates degradation time The differential; Indicates the initial degradation time.

[0065] Understandably, the professional performance tolerance of a system represents its fault tolerance capability, which is the integral of its professional performance margin over the remaining degradation time.

[0066] Step 41. Use the trapezoidal integral method to assess the system's performance tolerance. An approximate solution is performed to obtain the performance tolerance for degradation time in the discrete case, expressed as:

[0067] in, This indicates a focus on degradation time. Professional performance tolerance under discrete time conditions; q This represents the total number of elements in the degraded time series.

[0068] Furthermore, utilize specialized performance tolerances that focus on degradation time. Indicates system degradation time The approximate result of the professional performance tolerance of the system is expressed as:

[0069] in, Indicates degradation time The system is in state The system's internal dependent variables and external variables The approximate result of the professional performance tolerance under the given conditions.

[0070] Furthermore, the aforementioned professional performance tolerance of this invention refers to a single professional performance characteristic. For a system with multiple professional performance characteristics, the professional performance margins are respectively... The corresponding professional performance tolerance is Then the overall professional performance tolerance of the system is: .

[0071] It is understandable that the tolerance for all professional performance characteristics is set to a smaller value.

[0072] To illustrate the effectiveness of the method proposed in this invention, the following detailed description of the above technical solution of this invention is provided through a specific embodiment.

[0073] Based on the directed graph of the solar cell array's component structure, and considering that the solar cell array is a single-input single-output system, the number of functional paths of the solar cell array is obtained. Therefore, the structural tolerance of the solar cell array system is obtained as follows:

[0074] in, N j Indicates the first j The number of remaining cells in the battery string; Indicates the first j The total number of bypass diodes in the battery string; Indicates the total number of battery strings; Indicates the first j The first in the string of batteries i The total number of photovoltaic units connected to each bypass diode; The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for estimating system fault tolerance based on system component structure, characterized in that, The specific steps are as follows: Step 1. Construct a directed graph of the system based on a component-oriented architecture; The system includes a single-input single-output (SISO) system and a multiple-input multiple-output (MIMO) system; Step 2. Obtain the system structural fault tolerance based on the directed graph of the component-oriented system structure; For a single-input single-output system, based on the directed graph of the system, the redundancy between the starting point and the ending point of a single directed graph is obtained, and the redundancy is normalized to obtain the system structural fault tolerance. For a multiple-input multiple-output (MIMO) system, based on the directed graph of the MIMO system, the redundancy between multiple starting points and multiple ending points of the directed graph is obtained. This redundancy is used as an element of the fault tolerance matrix of the MIMO system. Valid start-end node pairs for the system's functional path are then selected, and the average structural fault tolerance of the valid start-end node pairs is used as the structural fault tolerance of the MIMO system.

2. The system fault tolerance estimation method according to claim 1, characterized in that, The expression for the structural fault tolerance of a single-input single-output (SISO) system is: in, Indicates the system in state Structural tolerance; Indicates the system in state Lower system directed graph From the starting point s To the finish line e The total number of all unique function paths; Indicates the system in state The system is a directed graph; This indicates the system in its initial state. The system is a directed graph; Indicates the system's degradation time state of time The following is a directed graph of component structure.

3. The system fault tolerance estimation method according to claim 1, characterized in that, The structural fault tolerance of a multiple-input multiple-output (MIMO) system is expressed as: in, P This represents the structural tolerance matrix of the system; Indicates the first i The starting point and the first directed graph k The structural tolerance of the start and end nodes of a directed graph. , , m Indicates the total number of starting points. n Indicates the total number at the finish line; Indicates the first i A starting point of a directed graph, Indicates the first k The endpoint of a directed graph.

4. The system fault tolerance estimation method according to claim 3, characterized in that, The redundancy matrix is ​​filtered and corrected using a Boolean matrix to obtain an effective redundancy matrix.

5. The system fault tolerance estimation method according to claim 4, characterized in that, Effective redundancy matrix U The expression is: Where A represents a Boolean matrix, ; Indicates the first i The starting point and the first directed graph k A pair of start and end nodes for the endpoint of a directed graph; No. i The starting point and the first directed graph k Redundancy of valid start and end node pairs at the endpoint of a directed graph. satisfy: in, This represents an invalid value.

6. The system fault tolerance estimation method according to claim 5, characterized in that, Based on the effective start-end node pairs obtained by filtering and correcting the tolerance matrix, the structural tolerance of the multi-input multi-output system is obtained. The expression is: 。 7. The system fault tolerance estimation method according to any one of claims 1-6, characterized in that, It also includes step 3, which quantifies the overall fault tolerance of the system based on the fault tolerance at the system structure level and the fault tolerance at the professional performance level.

Images