Safety assessment method and device for nuclear power system
By constructing a correlation between fault trees and dynamic event trees, and dynamically updating the failure probability in conjunction with equipment parameters, the problem of the disconnect between static probability and dynamic evolution in the safety assessment of nuclear power systems is solved, thereby improving the accuracy and reliability of the assessment.
Patent Information
- Application Number
- CN202511338544.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-18
- Publication Date
- 2026-01-23
AI Technical Summary
In existing safety assessment methods for nuclear power systems, fault trees and dynamic event trees cannot reflect the dynamic changes in the probability of equipment failure, leading to discrepancies between safety assessment results and actual accident scenarios.
By constructing the association between fault trees and dynamic event trees, and combining equipment parameters such as failure rate and maintenance rate, the failure probability of branch events is dynamically updated, thereby simulating the accident evolution process of nuclear power systems and obtaining a more realistic failure probability assessment.
It has improved the accuracy of safety assessments of nuclear power systems, reduced the deviation between risk assessment results and actual accident scenarios, and enhanced the credibility of safety assessments.
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Figure CN121389712A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of safety assessment technology, and in particular relates to a safety assessment method and apparatus for nuclear power systems. Background Technology
[0002] The core of nuclear power system safety lies in quantifying the associated risks of equipment failure and accident evolution. Probabilistic Safety Assessment (PSA) is the mainstream method. Its core objective is to quantitatively assess the probability of accidents occurring in complex engineering systems and the possible consequences of such accidents, thereby identifying system weaknesses and optimizing safety design.
[0003] Existing PSA relies on fault trees (FT) or dynamic event trees (DET). Fault trees are static tools that calculate the probability of the top event of the system based on a fixed failure probability; dynamic event trees combine simulation to simulate accident path branches, but the probability of branch events is calculated using static values.
[0004] Fault trees cannot reflect the dynamic changes in equipment failure probability over time or as the accident progresses; dynamic event trees ignore the impact of real-time operating status on probability. The above methods have the problem of being disconnected from static probability assessment and dynamic accident evolution, resulting in insufficient accuracy of safety assessment results and deviations between risk assessment results and actual accident scenarios. Summary of the Invention
[0005] This application provides a method and apparatus for safety assessment of a nuclear power system, which can associate event trees and fault trees to solve the problem of the disconnect between static probability and dynamic evolution, making the failure path probability more realistic, improving the accuracy of safety assessment results, and effectively reducing the deviation between risk assessment results and actual accident scenarios.
[0006] In a first aspect, embodiments of this application provide a safety assessment method for a nuclear power system, the method comprising:
[0007] Obtain first information about the nuclear power system to be analyzed, the first information including multiple component identifiers in the nuclear power system, the state type of the nuclear power system, and the equipment parameters of the components identified by the multiple component identifiers;
[0008] Based on the first information of the nuclear power system, a fault tree is constructed, the fault tree including the connection relationship between the basic events corresponding to the component and the top event corresponding to the nuclear power system;
[0009] Based on the device parameters of the components corresponding to the multiple basic events, a first correspondence is determined. The first correspondence includes multiple first runtimes of the components corresponding to each basic event and a first failure probability corresponding to each first runtime.
[0010] The accident evolution process of the nuclear power system is simulated according to the first correspondence to obtain simulation information. The simulation information includes a dynamic event tree and the total failure probability of each accident path in the dynamic event tree. The dynamic event tree includes multiple accident paths, and each accident path includes multiple branch events. The total failure probability of each accident path is determined according to the second failure probability of the multiple branch events in each accident path. The second failure probability of the branch events is determined according to the first failure probability in the first correspondence.
[0011] The safety of the nuclear power system is assessed based on the simulation information, and the assessment results are obtained.
[0012] In one embodiment of this application, determining the first correspondence based on the device parameters of the components corresponding to the plurality of basic events includes:
[0013] For each component corresponding to the basic event, a first failure probability corresponding to each first runtime is determined based on the component's device parameters and each first runtime.
[0014] The first correspondence is obtained by associating multiple first runtimes of the component corresponding to each basic event with the first failure probability corresponding to each first runtime, and the multiple first runtimes are different.
[0015] In one embodiment of this application, the device parameters include failure rate and maintenance rate;
[0016] For each component corresponding to the basic event, determining the first failure probability corresponding to each first runtime based on the component's device parameters and each first runtime includes:
[0017] For each component corresponding to the basic event, if the component is a non-repairable component, the first failure probability corresponding to each first runtime of the component is determined based on the failure rate of the component and each first runtime.
[0018] or,
[0019] For each component corresponding to the basic event, if the component is a repairable component, the first failure probability corresponding to each first runtime of the component is determined based on the component's repair rate, the component's failure rate, and each first runtime.
[0020] In one embodiment of this application, the step of simulating the accident evolution process of the nuclear power system according to the first correspondence to obtain simulation information includes:
[0021] Obtain second information, which includes the structural parameters, initial conditions, boundary conditions, physical equation-related parameters, and control logic of the nuclear power system;
[0022] The simulation tool is invoked to simulate the accident evolution process of the nuclear power system based on the first correspondence and the second information. During the simulation, if the current conditions meet the preset simulation termination conditions, a dynamic event tree is obtained.
[0023] The simulation information is obtained based on the dynamic event tree.
[0024] In one embodiment of this application, the simulation information further includes a second runtime corresponding to each branch event, and the second failure probability of the branch event is determined according to the following method:
[0025] For each branch event, the branch event is matched with the basic event in the first correspondence to determine the basic event that matches the branch event;
[0026] The second runtime corresponding to the branch event is matched with the first runtime corresponding to the matching basic event to determine the first runtime that matches the second runtime.
[0027] The first failure probability corresponding to the first matching runtime is used as the second failure probability of the branch event.
[0028] In one embodiment of this application, the total failure probability of each accident path is determined as follows:
[0029] For each of the aforementioned incident paths, the second failure probabilities corresponding to multiple branch events in the incident path are multiplied together to obtain a first value;
[0030] The first value is taken as the total failure probability of the accident path.
[0031] In one embodiment of this application, obtaining the first information of the nuclear power system to be analyzed includes:
[0032] Receive simulation request;
[0033] The simulation request is parsed to obtain the first information of the nuclear power system to be analyzed.
[0034] Secondly, embodiments of this application provide a safety assessment apparatus for a nuclear power system, the apparatus comprising:
[0035] The acquisition module is used to acquire first information of the nuclear power system to be analyzed. The first information includes multiple component identifiers in the nuclear power system, the state type of the nuclear power system, and the equipment parameters of the components identified by the multiple component identifiers.
[0036] A construction module is used to construct a fault tree based on the first information of the nuclear power system. The fault tree includes the connection relationship between the basic events corresponding to the component and the top event corresponding to the nuclear power system.
[0037] The determining module is configured to determine a first correspondence relationship based on the device parameters of the components corresponding to the multiple basic events. The first correspondence relationship includes multiple first runtimes of the components corresponding to each basic event and a first failure probability corresponding to each first runtime.
[0038] The simulation module is used to simulate the accident evolution process of the nuclear power system according to the first correspondence relationship to obtain simulation information. The simulation information includes a dynamic event tree and the total failure probability of each accident path in the dynamic event tree. The dynamic event tree includes multiple accident paths, and each accident path includes multiple branch events. The total failure probability of each accident path is determined according to the second failure probability of the multiple branch events in each accident path. The second failure probability of the branch events is determined according to the first failure probability in the first correspondence relationship.
[0039] The evaluation module is used to evaluate the safety of the nuclear power system based on the simulation information and obtain the evaluation results.
[0040] In one embodiment of this application, the determining module includes a first determining submodule and a second determining submodule;
[0041] The first determining submodule is used to determine, for each component corresponding to each basic event, a first failure probability corresponding to each first runtime based on the device parameters of the component and each first runtime.
[0042] The second determining submodule is used to associate multiple first runtimes of the component corresponding to each basic event with a first failure probability corresponding to each first runtime to obtain the first correspondence relationship, wherein the multiple first runtimes are different.
[0043] In one embodiment of this application, the first determining submodule includes a first determining subunit and a second determining subunit;
[0044] The first determining subunit is configured to, for each component corresponding to the basic event, determine the first failure probability corresponding to each first runtime of the component, based on the failure rate of the component and each first runtime, in the case that the component is a non-repairable component;
[0045] The second determining subunit is configured to, for each component corresponding to the basic event, and if the component is a repairable component, determine the first failure probability corresponding to each first runtime of the component based on the component's repair rate, the component's failure rate, and each first runtime.
[0046] Thirdly, embodiments of this application provide an electronic device, including: a processor and a memory storing computer program instructions;
[0047] When the processor executes the computer program instructions, it implements the safety assessment method for nuclear power systems as described in the first aspect.
[0048] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer program instructions, which, when executed by a processor, implement the safety assessment method for a nuclear power system as described in the first aspect.
[0049] Fifthly, embodiments of this application provide a computer program product in which instructions, when executed by a processor of an electronic device, cause the electronic device to perform the safety assessment method for a nuclear power system as described in the first aspect.
[0050] This embodiment provides a safety assessment method and apparatus for a nuclear power system. The method involves acquiring first information about the nuclear power system to be analyzed, including multiple component identifiers, the state type of the nuclear power system, and equipment parameters of the components identified by the component identifiers. Based on the first information, a fault tree is constructed, comprising the connection relationships between basic events corresponding to each component and the top event corresponding to the nuclear power system. A first correspondence is determined based on the equipment parameters of the components corresponding to the multiple basic events, including multiple first runtimes of the components corresponding to each basic event and a first failure probability corresponding to each first runtime. The accident evolution process of the nuclear power system is simulated based on the first correspondence. The simulation information includes a dynamic event tree and the total failure probability of each accident path in the dynamic event tree. The dynamic event tree includes multiple accident paths, and each accident path includes multiple branch events. The total failure probability of each accident path is determined based on the second failure probabilities of the multiple branch events in each accident path. The second failure probabilities of the branch events are determined based on the first failure probabilities in the first correspondence relationship. The safety of the nuclear power system is evaluated based on the simulation information to obtain the evaluation results. The event tree and fault tree are correlated to solve the problem of the disconnect between static probability and dynamic evolution, making the failure path probabilities more realistic, improving the accuracy of the safety assessment results, and effectively reducing the deviation between the risk assessment results and the actual accident scenario. Attached Figure Description
[0051] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0052] Figure 1 This is a flowchart illustrating a safety assessment method for a nuclear power system provided in an embodiment of this application;
[0053] Figure 2 This is another flowchart illustrating the safety assessment method for nuclear power systems provided in this application embodiment;
[0054] Figure 3 This is a schematic diagram of the structure of the safety assessment device for a nuclear power system provided in the embodiments of this application;
[0055] Figure 4 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation
[0056] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.
[0057] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.
[0058] To address the problems of the prior art, embodiments of this application provide a method and apparatus for safety assessment of nuclear power systems. The safety assessment method for nuclear power systems provided in this application embodiment is described below.
[0059] Figure 1 A flowchart illustrating a safety assessment method for a nuclear power system according to an embodiment of this application is shown. Figure 1 As shown, the safety assessment method for nuclear power systems provided in this application embodiment, applied to electronic equipment, includes the following steps 101-105, wherein:
[0060] Step 101: Obtain first information of the nuclear power system to be analyzed. The first information includes multiple component identifiers in the nuclear power system, the state type of the nuclear power system, and the equipment parameters of the components identified by the multiple component identifiers.
[0061] In this embodiment, the first information of the nuclear power system to be analyzed is obtained. The first information includes multiple component identifiers in the nuclear power system, the state type of the nuclear power system, and the equipment parameters of the components identified by the multiple component identifiers. The equipment parameters include maintenance rate and failure rate. The state type of the nuclear power system is divided into normal operation, complete failure, and partial failure.
[0062] Step 102: Based on the first information of the nuclear power system, construct a fault tree, wherein the fault tree includes the connection relationship between the basic events corresponding to the component and the top event corresponding to the nuclear power system.
[0063] In this embodiment, a fault tree is constructed based on the first information of the nuclear power system. For example, the failure mode of the system or equipment is taken as the top event, and Boolean logic gates (AND gate, OR gate, etc.) are used to decompose it layer by layer to the directly quantifiable basic events. The failure behavior of the basic events is usually represented by the failure rate or maintenance rate of the equipment / component as statistical parameters, which respectively reflect the probability of the equipment transitioning from normal to failure and the probability of the equipment recovering from failure to normal.
[0064] For example, first, define the top event: clearly define the failure mode of the system or equipment as the top event, such as the failure of the cooling system in a nuclear power system; event decomposition and logic modeling: decompose the top event layer by layer into intermediate events and basic events, and connect them through logic gates (AND / OR). For example: pump failure, power supply failure, valve jamming, etc.; parameterize basic events: for each basic event, determine the failure probability using the failure rate or maintenance rate corresponding to the component of the basic event; quantitatively calculate the top event probability: for a static fault tree, the failure probability of the top event can be expressed as a function of the failure probabilities of the basic events through the minimum cut set method.
[0065] The fault tree is obtained in the above manner. The fault tree includes the connection relationship between the basic events corresponding to the component and the top event corresponding to the nuclear power system.
[0066] Step 103: Determine a first correspondence relationship based on the device parameters of the components corresponding to the multiple basic events. The first correspondence relationship includes multiple first runtimes of the components corresponding to each basic event and a first failure probability corresponding to each first runtime.
[0067] In this embodiment, a first correspondence is determined based on the device parameters of the components corresponding to multiple basic events, such as failure rate or maintenance rate. The first correspondence includes multiple first running times of the components corresponding to each basic event and a first failure probability corresponding to each first running time. The multiple first running times are all different.
[0068] Step 104: Simulate the accident evolution process of the nuclear power system according to the first correspondence relationship to obtain simulation information. The simulation information includes a dynamic event tree and the total failure probability of each accident path in the dynamic event tree. The dynamic event tree includes multiple accident paths, and each accident path includes multiple branch events. The total failure probability of each accident path is determined based on the second failure probability of the multiple branch events in each accident path. The second failure probability of the branch events is determined based on the first failure probability in the first correspondence relationship.
[0069] In this embodiment, the accident evolution process of the nuclear power system is simulated according to the first correspondence to obtain simulation information. The simulation information includes a dynamic event tree and the total failure probability of each accident path in the dynamic event tree. The dynamic event tree includes multiple accident paths, and each accident path includes multiple branch events. For each accident path, the total failure probability of the accident path is determined according to the second failure probability of the multiple branch events included in the accident path. The second failure probability of each branch event is determined according to the first failure probability in the first correspondence.
[0070] Step 105: Evaluate the safety of the nuclear power system based on the simulation information and obtain the evaluation results.
[0071] In this embodiment, the safety of the nuclear power system is assessed based on simulation information. This assessment is achieved using simulation tools, and the results are used to analyze potential accidents in the nuclear power system.
[0072] In this embodiment, first information about the nuclear power system to be analyzed is obtained. This first information includes multiple component identifiers of the nuclear power system, the state type of the nuclear power system, and equipment parameters of the components identified by the multiple component identifiers. A fault tree is constructed based on the first information of the nuclear power system. The fault tree includes the connection relationship between basic events corresponding to components and top events corresponding to the nuclear power system. A first correspondence is determined based on the equipment parameters of the components corresponding to multiple basic events. The first correspondence includes multiple first runtimes of the components corresponding to each basic event and a first failure probability corresponding to each first runtime. The accident evolution process of the nuclear power system is simulated based on the first correspondence to obtain simulation information. The simulation information includes a dynamic event tree and the dynamic event tree. The total failure probability of each accident path in the dynamic event tree is determined based on the second failure probability of the multiple branch events in each accident path. The second failure probability of the branch events is determined based on the first failure probability in the first correspondence. Furthermore, the safety of the nuclear power system is evaluated based on simulation information to obtain evaluation results. The event tree and fault tree are associated to solve the problem of the disconnect between static probability and dynamic evolution, making the failure path probability more realistic, improving the accuracy of safety assessment results, and effectively reducing the deviation between risk assessment results and actual accident scenarios.
[0073] In one embodiment of this application, determining the first correspondence based on the device parameters of the components corresponding to the plurality of basic events includes:
[0074] For each component corresponding to the basic event, a first failure probability corresponding to each first runtime is determined based on the component's device parameters and each first runtime.
[0075] The first correspondence is obtained by associating multiple first runtimes of the component corresponding to each basic event with the first failure probability corresponding to each first runtime, and the multiple first runtimes are different.
[0076] In this embodiment, for each component corresponding to a basic event, the first failure probability corresponding to each first runtime is calculated based on the component's device parameters and each first runtime. The multiple first runtimes are different, such as 3h, 6h, 12h, 24h, etc. The multiple first runtimes of the component corresponding to each basic event and the first failure probability corresponding to each first runtime are associated to obtain a first correspondence.
[0077] As shown in Table 1, Table 1 is an example of a first correspondence relationship. The component is an injection pump, the state type is running, the component's basic event is running failure, and the running time includes 3h, 12h and 24h. Each running time corresponds to a failure probability. The first failure probability corresponding to 3h is 0.0003, the first failure probability corresponding to 12h is 0.0012, and the first failure probability corresponding to 24h is 0.0025.
[0078] Table 1
[0079]
[0080] By setting the first correspondence, a mapping relationship between runtime and failure probability is provided for subsequent event trees.
[0081] In one embodiment of this application, the device parameters include failure rate and maintenance rate;
[0082] For each component corresponding to the basic event, determining the first failure probability corresponding to each first runtime based on the component's device parameters and each first runtime includes:
[0083] For each component corresponding to the basic event, if the component is a non-repairable component, the first failure probability corresponding to each first runtime of the component is determined based on the failure rate of the component and each first runtime.
[0084] or,
[0085] For each component corresponding to the basic event, if the component is a repairable component, the first failure probability corresponding to each first runtime of the component is determined based on the component's repair rate, the component's failure rate, and each first runtime.
[0086] In this embodiment, the equipment parameters of the component include maintenance rate and failure rate. When determining the first failure probability, it is necessary to determine which type of component the component belongs to, which is divided into repairable or non-repairable components. Non-repairable components refer to components that are not designed to be disassembled and repaired, or whose repair costs far exceed replacement costs, and whose original performance and safety cannot be restored after repair. The core logic of these components is to replace rather than repair, that is, after a failure, the whole component needs to be replaced, rather than repairing the internal sub-parts. On the other hand, repairable components refer to components that are designed to support disassembly and replacement of internal sub-parts, and whose repair costs are lower than replacement costs, and whose original performance and safety can be restored after repair. The core logic of these components is repair and reuse, and they usually have reserved maintenance interfaces, and the sub-parts can be purchased separately.
[0087] If the component is non-repairable, the first probability of failure is determined based on the failure rate; if the component is repairable, the first probability of failure is determined based on both the repair rate and the failure rate.
[0088] Specifically, for each component corresponding to a basic event, if the component is a non-repairable component, the first failure probability corresponding to each first runtime of the component is calculated based on the component's failure rate and each first runtime. Specifically:
[0089] P fail (t)=1-e -λt (1)
[0090] Among them, P fail (t) represents the first failure probability during the first runtime, λ represents the failure rate, and t represents the first runtime.
[0091] Specifically, for each component corresponding to a basic event, assuming the component is a repairable component, the first failure probability corresponding to each first runtime of the component is calculated based on the component's repair rate, failure rate, and each first runtime. Specifically:
[0092]
[0093] Where Q(t) is the first failure probability during the first runtime, λ is the failure rate, and μ is the maintenance rate.
[0094] By distinguishing whether a component is repairable, two methods for calculating the probability of failure are provided, applicable to different components.
[0095] In one embodiment of this application, the step of simulating the accident evolution process of the nuclear power system according to the first correspondence to obtain simulation information includes:
[0096] Obtain second information, which includes the structural parameters, initial conditions, boundary conditions, physical equation-related parameters, and control logic of the nuclear power system;
[0097] The simulation tool is invoked to simulate the accident evolution process of the nuclear power system based on the first correspondence and the second information. During the simulation, if the current conditions meet the preset simulation termination conditions, a dynamic event tree is obtained.
[0098] The simulation information is obtained based on the dynamic event tree.
[0099] In this embodiment, second information is obtained, including the structural parameters, initial conditions, boundary conditions, physical equation parameters, and control logic of the nuclear power system. A simulation tool is invoked to simulate the accident evolution process of the nuclear power system based on the first correspondence and the second information. During the simulation, if the current conditions meet preset simulation termination conditions, such as the current time reaching a preset termination time, or each path being in a stable state, or the probability value being less than a threshold (e.g., 1e-6), the simulation stops, and a dynamic event tree is obtained. Further, simulation information is obtained based on the dynamic event tree.
[0100] Alternatively, the simulation tool can be a nuclear reactor system thermal-hydraulic analysis program.
[0101] Optionally, whenever a branch condition of a node in the event tree is reached, such as the water level in the tank dropping to a threshold, the cumulative runtime of this node is obtained, i.e., the second runtime. Based on the second runtime, the failure probability is extracted from the first correspondence and used as the second failure probability.
[0102] The branching conditions of an event tree refer to the criteria for determining whether an uncertain event may occur in a nuclear power system at a specific time or under a specific condition. It is often related to the operating status (success / failure), operation actions (executed / not executed), and safety protection logic triggering (action / not action) of the nuclear power system or its subsystems.
[0103] Optionally, the DET evolution and termination phase includes: generating branch paths based on simulation results: each node is generated step by step according to the physical simulation and fault tree probability feedback of the simulation tool; after the current node evolves, the next generation node is generated according to the branching rules; each node is generated step by step according to the physical simulation and fault tree probability feedback of RELAP5; continuous simulation and determination of termination conditions: the system continues to execute the simulation until the preset simulation termination conditions are met; outputting simulation information: when the current conditions meet the preset simulation termination conditions, the dynamic event tree and the failure probability of each path are obtained. The dynamic event tree is a dynamic event tree with time as the axis and state as the branch.
[0104] By combining the second information (the information required for simulation) with the first correspondence, more accurate simulation information can be obtained.
[0105] In one embodiment of this application, the simulation information further includes a second runtime corresponding to each branch event, and the second failure probability of the branch event is determined according to the following method:
[0106] For each branch event, the branch event is matched with the basic event in the first correspondence to determine the basic event that matches the branch event;
[0107] The second runtime corresponding to the branch event is matched with the first runtime corresponding to the matching basic event to determine the first runtime that matches the second runtime.
[0108] The first failure probability corresponding to the first matching runtime is used as the second failure probability of the branch event.
[0109] In this embodiment, a failure probability, i.e., a second failure probability, needs to be determined for each branch event. For each branch event, the branch event is matched with the basic events in the first correspondence to determine the basic events that match the branch event. Further, the second runtime corresponding to the branch event is matched with the first runtime corresponding to the matched basic event to determine the first runtime that matches the second runtime. The first failure probability corresponding to the matched first runtime is used as the failure probability of the branch event, i.e., the second failure probability.
[0110] The failure probability of each branch event can be accurately determined through the first correspondence, so as to obtain a more accurate total failure probability of the accident path in the future.
[0111] In one embodiment of this application, the total failure probability of each accident path is determined as follows:
[0112] For each of the aforementioned incident paths, the second failure probabilities corresponding to multiple branch events in the incident path are multiplied together to obtain a first value;
[0113] The first value is taken as the total failure probability of the accident path.
[0114] In this embodiment, for each incident path, the second failure probabilities corresponding to multiple branch events in the incident path are multiplied together. For example, if an incident path includes n branch events, their probabilities are:
[0115]
[0116] Where: P Branch.i It is the second failure probability of the i-th branch event, where n is the number of branch events.
[0117] The above scheme can calculate a more accurate total failure probability of the accident path, making the accident path probability more realistic and improving the credibility of the simulation results.
[0118] In one embodiment of this application, obtaining the first information of the nuclear power system to be analyzed includes:
[0119] Receive simulation request;
[0120] The simulation request is parsed to obtain the first information of the nuclear power system to be analyzed.
[0121] In this embodiment, a simulation request is received, the simulation request is interpreted, and the first information of the nuclear power system to be analyzed is obtained. The first information includes multiple component identifiers in the nuclear power system, the state type of the nuclear power system, and the equipment parameters of the components identified by the multiple component identifiers.
[0122] Optionally, the execution entity is an analysis platform, see [link to relevant documentation]. Figure 2 Users can customize multiple component identifiers, state types, and simulation durations of a nuclear power system in the terminal. Based on these component identifiers, the terminal obtains the equipment parameters of the components identified by those identifiers. The terminal sends a simulation request to the analysis platform. The analysis platform receives the simulation request and obtains the first information of the nuclear power system, including the simulation duration, which is used to determine multiple first runtimes. The analysis platform calls the fault tree engine to construct a fault tree. The analysis platform sends a request to the fault tree engine requesting failure probability calculation, which includes the multiple component identifiers, state types, and simulation durations of the nuclear power system. Upon receiving the request, the fault tree engine calls the equipment parameters and constructs a fault tree based on the equipment parameters, the multiple component identifiers, the state types, the equipment parameters of the components identified by those identifiers, and the simulation duration. The fault tree engine determines the first correspondence based on the equipment parameters of the components corresponding to multiple basic events and returns this first correspondence to the analysis platform. The analysis platform stores this first correspondence in a database as a dynamic probability data source for dynamic event tree simulation.
[0123] Furthermore, the analysis platform simulates the accident evolution process of the nuclear power system based on the first correspondence, obtaining simulation information. Specifically, it acquires second information, which includes the structural parameters, initial conditions, boundary conditions, physical equation-related parameters, and control logic of the nuclear power system; see [link to relevant documentation]. Figure 2 The analysis platform initiates a simulation, which involves calling simulation tools to simulate the accident evolution process of the nuclear power system based on the first correspondence and the second information. During the simulation, if the current conditions meet the preset simulation termination conditions, a dynamic event tree is obtained; simulation information is then obtained based on the dynamic event tree. The analysis platform assesses the safety of the nuclear power system based on the simulation information, obtains the assessment results, and provides support for safety margin assessment or emergency decision-making based on the assessment results.
[0124] This embodiment can correlate the simulation progress of fault tree and accident tree, solving the problem of disconnect between static probability and dynamic evolution; the probability of branch events is dynamically updated with the running time, making the accident path probability more realistic and improving the credibility of simulation results; the entire process from probability pre-calculation to branch assignment is executed automatically, reducing manual intervention; and it supports docking with fault tree engines and simulation tools.
[0125] Figure 3 A structural diagram of a safety assessment apparatus for a nuclear power system provided in an embodiment of this application is shown. Figure 3 As shown, the safety assessment device 300 for nuclear power systems includes:
[0126] The acquisition module 301 is used to acquire first information of the nuclear power system to be analyzed. The first information includes multiple component identifiers in the nuclear power system, the state type of the nuclear power system, and the equipment parameters of the components identified by the multiple component identifiers.
[0127] The construction module 302 is used to construct a fault tree based on the first information of the nuclear power system. The fault tree includes the connection relationship between the basic events corresponding to the component and the top event corresponding to the nuclear power system.
[0128] The determining module 303 is used to determine a first correspondence relationship based on the device parameters of the components corresponding to the multiple basic events. The first correspondence relationship includes multiple first runtimes of the components corresponding to each basic event and a first failure probability corresponding to each first runtime.
[0129] The simulation module 304 is used to simulate the accident evolution process of the nuclear power system according to the first correspondence relationship to obtain simulation information. The simulation information includes a dynamic event tree and the total failure probability of each accident path in the dynamic event tree. The dynamic event tree includes multiple accident paths, and each accident path includes multiple branch events. The total failure probability of each accident path is determined according to the second failure probability of the multiple branch events in each accident path. The second failure probability of the branch events is determined according to the first failure probability in the first correspondence relationship.
[0130] The evaluation module 305 is used to evaluate the safety of the nuclear power system based on the simulation information and obtain the evaluation results.
[0131] In one embodiment of this application, the determining module 303 includes a first determining submodule and a second determining submodule;
[0132] The first determining submodule is used to determine, for each component corresponding to the basic event, a first failure probability corresponding to each first runtime based on the device parameters of the component and each first runtime.
[0133] The second determining submodule is used to associate multiple first runtimes of the component corresponding to each basic event with a first failure probability corresponding to each first runtime to obtain the first correspondence relationship, wherein the multiple first runtimes are different.
[0134] In one embodiment of this application, the first determining submodule is specifically configured to, for each component corresponding to the basic event, determine the first failure probability corresponding to each first runtime of the component based on the failure rate of the component and each first runtime when the component is a non-repairable component; or, for each component corresponding to the basic event, determine the first failure probability corresponding to each first runtime of the component based on the repair rate of the component, the failure rate of the component, and each first runtime when the component is a repairable component.
[0135] In one embodiment of this application, the simulation module 304 includes a first acquisition submodule, a simulation submodule, and a third determination submodule;
[0136] The first acquisition submodule is used to acquire second information, which includes the structural parameters, initial conditions, boundary conditions, physical equation-related parameters, and control logic of the nuclear power system.
[0137] The simulation submodule is used to call the simulation tool to simulate the accident evolution process of the nuclear power system according to the first correspondence and the second information. During the simulation, if the current conditions meet the preset simulation termination conditions, a dynamic event tree is obtained.
[0138] The third determining submodule is used to obtain the simulation information based on the dynamic event tree.
[0139] In one embodiment of this application, the safety assessment device for a nuclear power system further includes a first determining module;
[0140] The first determining module is configured to, for each branch event, match the branch event with the basic event in the first correspondence relationship to determine the basic event that matches the branch event; match the second runtime corresponding to the branch event with the first runtime corresponding to the matched basic event to determine the first runtime that matches the second runtime; and use the first failure probability corresponding to the matched first runtime as the second failure probability of the branch event.
[0141] In one embodiment of this application, the safety assessment device for a nuclear power system further includes a second determining module;
[0142] The second determining module is used to multiply the second failure probabilities corresponding to multiple branch events in each accident path to obtain a first value.
[0143] The first value is taken as the total failure probability of the accident path.
[0144] In one embodiment of this application, the safety assessment device for a nuclear power system further includes a transceiver module;
[0145] The transceiver module is used to receive simulation requests;
[0146] The acquisition module 301 is also used to parse the simulation request and acquire the first information of the nuclear power system to be analyzed.
[0147] The nuclear power system safety assessment device provided in this application embodiment can realize all the processes implemented in the aforementioned nuclear power system safety assessment method embodiment and achieve the same technical effect. To avoid repetition, it will not be described again here.
[0148] Figure 4 A schematic diagram of the hardware structure of the electronic device provided in an embodiment of this application is shown.
[0149] The electronic device may include a processor 401 and a memory 402 storing computer program instructions.
[0150] Specifically, the processor 401 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this application.
[0151] Memory 402 may include mass storage for data or instructions. For example, and not limitingly, memory 402 may include a hard disk drive (HDD), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 402 may include removable or non-removable (or fixed) media. Where appropriate, memory 402 may be internal or external to the integrated gateway disaster recovery device. In a particular embodiment, memory 402 is non-volatile solid-state memory.
[0152] Memory may include read-only memory (ROM), random access memory (RAM), disk storage media devices, optical storage media devices, flash memory devices, and electrical, optical, or other physical / tangible memory storage devices. Therefore, typically, memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the methods according to the first or second aspect of this disclosure.
[0153] The processor 401 implements any of the methods described above in the above embodiments by reading and executing computer program instructions stored in the memory 402.
[0154] In one example, the electronic device may also include a communication interface 403 and a bus 410. For example, Figure 4 As shown, the processor 401, memory 402, and communication interface 403 are connected through bus 410 and complete communication with each other.
[0155] The communication interface 403 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of this application.
[0156] Bus 410 includes hardware, software, or both, that couples components of a method or electronic device as described above together. For example, and not as a limitation, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Microchannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 410 may include one or more buses. Although specific buses are described and illustrated in embodiments of this application, any suitable bus or interconnect is contemplated herein.
[0157] Alternatively, embodiments of this application may be implemented using a computer storage medium. This computer storage medium stores computer program instructions; when these computer program instructions are executed by a processor, they implement any of the nuclear power system safety assessment methods described in the above embodiments.
[0158] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described as examples. However, the method process of this application is not limited to the specific steps described. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.
[0159] The functional blocks shown in the above-described structural diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. Programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.
[0160] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.
[0161] The aspects of this disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block in the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by special-purpose hardware performing the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.
[0162] The above description is merely a specific implementation of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.
Claims
1. A method of safety assessment of a nuclear power system, characterized by, The method comprises: obtaining first information of a nuclear power system to be analyzed, the first information comprising a plurality of component identifiers in the nuclear power system, a state type of the nuclear power system, and device parameters of components identified by the plurality of component identifiers; constructing a fault tree according to the first information of the nuclear power system, the fault tree comprising a connection relationship between basic events corresponding to the components and a top event corresponding to the nuclear power system; determining a first correspondence relationship according to the device parameters of the components corresponding to a plurality of the basic events, the first correspondence relationship comprising a plurality of first running durations of the components corresponding to each of the basic events and a first failure probability corresponding to each of the first running durations; simulating an accident evolution process of the nuclear power system according to the first correspondence relationship to obtain simulation information, the simulation information comprising a dynamic event tree and a total failure probability of each accident path in the dynamic event tree, the dynamic event tree comprising a plurality of accident paths, each of the accident paths comprising a plurality of branch events, and the total failure probability of each of the accident paths being determined according to second failure probabilities of the branch events in each of the accident paths, the second failure probability of the branch event being determined according to the first failure probability in the first correspondence relationship; evaluating the safety of the nuclear power system according to the simulation information to obtain an evaluation result.
2. The safety assessment method of a nuclear power system according to claim 1, characterized by, The determining of the first correspondence relationship according to the device parameters of the components corresponding to a plurality of the basic events comprises: for each of the components corresponding to the basic events, determining the first failure probability corresponding to each of the first running durations according to the device parameters of the component and each of the first running durations; associating the plurality of first running durations of each of the components corresponding to the basic events and the first failure probability corresponding to each of the first running durations to obtain the first correspondence relationship, the plurality of first running durations being different from each other.
3. The safety assessment method of a nuclear power system according to claim 2, characterized by, The device parameters comprise a failure rate and a repair rate; The determining of the first failure probability corresponding to each of the first running durations according to the device parameters of the component and each of the first running durations for each of the components corresponding to the basic events comprises: for each of the components corresponding to the basic events, in a case where the component is an unrepairable component, determining the first failure probability corresponding to each of the first running durations of the component according to the failure rate of the component and each of the first running durations; or, for each of the components corresponding to the basic events, in a case where the component is a repairable component, determining the first failure probability corresponding to each of the first running durations of the component according to the repair rate of the component, the failure rate of the component, and each of the first running durations.
4. The safety assessment method of a nuclear power system according to claim 1, characterized by, The simulating of the accident evolution process of the nuclear power system according to the first correspondence relationship to obtain simulation information comprises: obtaining second information, the second information comprising structural parameters, initial conditions, boundary conditions, physical equation related parameters, and control logic of the nuclear power system; The simulation tool is invoked to simulate an accident evolution process of the nuclear power system according to the first correspondence and the second information, and in the simulation process, a dynamic event tree is obtained when a current condition meets a preset simulation termination condition; The simulation information is obtained according to the dynamic event tree.
5. The safety assessment method of a nuclear power system according to claim 1, characterized by, The simulation information further includes a second running duration corresponding to each branch event, and a second failure probability of the branch event is determined in the following manner: For each branch event, the branch event is matched with the basic events in the first correspondence to determine a basic event matched with the branch event; The second running duration corresponding to the branch event is matched with a first running duration corresponding to the matched basic event to determine a first running duration matched with the second running duration; A first failure probability corresponding to the matched first running duration is taken as the second failure probability of the branch event.
6. The safety assessment method of a nuclear power system according to Claim 1, wherein, A total failure probability of each accident path is determined in the following manner: For each accident path, the second failure probabilities corresponding to the branch events in the accident path are multiplied to obtain a first value; The first value is taken as the total failure probability of the accident path.
7. The safety assessment method of a nuclear power system according to any one of claims 1 to 6, characterized in that, The first information of the nuclear power system to be analyzed is obtained in the following manner: A simulation request is received; The simulation request is parsed to obtain the first information of the nuclear power system to be analyzed.
8. A safety assessment device for a nuclear power system, characterized by, The apparatus includes: An obtaining module is configured to obtain first information of a nuclear power system to be analyzed, the first information including a plurality of component identifiers in the nuclear power system, a state type of the nuclear power system, and device parameters of components identified by the plurality of component identifiers; A constructing module is configured to construct a fault tree according to the first information of the nuclear power system, the fault tree including a connection relationship between basic events corresponding to the components and a top event corresponding to the nuclear power system; A determining module is configured to determine a first correspondence according to the device parameters of the components corresponding to the plurality of basic events, the first correspondence including a plurality of first running durations of the components corresponding to each basic event and a first failure probability corresponding to each first running duration; A simulation module is configured to simulate an accident evolution process of the nuclear power system according to the first correspondence to obtain simulation information, the simulation information including a dynamic event tree and a total failure probability of each accident path in the dynamic event tree, the dynamic event tree including a plurality of accident paths, each accident path including a plurality of branch events, and the total failure probability of each accident path being determined according to second failure probabilities of the branch events in each accident path, the second failure probabilities of the branch events being determined according to the first failure probabilities in the first correspondence; An evaluating module is configured to evaluate the safety of the nuclear power system according to the simulation information to obtain an evaluation result.
9. The safety assessment apparatus of a nuclear power system according to claim 8, characterized by, The determining module includes a first determining submodule and a second determining submodule; The first determining sub-module is configured to determine, for each component corresponding to each basic event, a first failure probability corresponding to each first operation duration according to the equipment parameter of the component and each first operation duration. The second determining sub-module is configured to associate the first operation durations of the component corresponding to each basic event and the first failure probabilities corresponding to each first operation duration to obtain the first corresponding relationship, and the first operation durations are different from each other.
10. The safety assessment apparatus of a nuclear power system according to claim 9, wherein The first determining sub-module includes a first determining subunit and a second determining subunit. The first determining subunit is configured to, for each component corresponding to each basic event, determine, in a case where the component is an unrepairable component, the first failure probability corresponding to each first operation duration of the component according to the failure rate of the component and each first operation duration. The second determining subunit is configured to, for each component corresponding to each basic event, determine, in a case where the component is a repairable component, the first failure probability corresponding to each first operation duration of the component according to the repair rate of the component, the failure rate of the component and each first operation duration.