Accident handling strategy analysis method and system for micro reactor

Abstract

The invention discloses an accident handling strategy analysis method and system for a micro reactor, and relates to the technical field of nuclear power design. The method comprises the following steps: S1, classifying originating accidents based on multi-dimensional accident features; s2, a typical accident is selected from each type of originating accidents, and a processing strategy of the typical accident is obtained through analysis; s3, performing operation step decomposition on the processing strategy of the typical accident; s4, comparing operation steps of processing strategies of typical accidents, concluding general operations and analyzing judgment conditions of differentiated operations; s5, the general operation and the differential operation are integrated, and a normalized accident processing strategy is generated according to sequential logic; and S6, verifying the effectiveness of the accident processing strategy. According to the method, all accidents are dealt with by applying a normalized accident handling strategy based on the requirements of the operation scene of the micro-reactor and aiming at the design characteristics of the micro-reactor and the characteristics of accident operation response, so that the operation requirements after the accidents are greatly simplified.

Description

Technical Field

[0001] This invention relates to the field of nuclear power design technology, and more specifically to an accident handling strategy analysis method and system for micro-miniature reactors. Background Technology

[0002] As a novel energy source, miniature reactors (MMRs) offer advantages such as relatively easy transportation and high power generation capacity, making them suitable for powering micro-grids in remote areas like islands and mines. Due to their specific application scenarios, MMR design must consider minimizing post-accident maintenance requirements to reduce the number of operators needed, thereby improving operational economy and convenience. Furthermore, the complex accident management strategies of traditional nuclear power units are not well-suited for gas-cooled MMRs; therefore, optimization of MMR accident management strategies is necessary.

[0003] Generally, micro-small reactors are mostly based on fourth-generation reactors, which have high inherent safety, simple system composition and passive measures, all of which provide a basis for further optimization of post-accident strategies.

[0004] As a novel distributed energy source, micro-reactors (MRTs) possess significant application value in areas far from the main power grid, such as islands, remote mining areas, border outposts, and isolated communities, due to their modular design, ease of transportation and deployment, and high power density. They can provide reliable power support for micro-grids. Given the remote nature of their application scenarios and limited operational resources, MRT design must prioritize operational autonomy and simplified post-accident handling. This aims to significantly reduce operational complexity and reliance on external personnel skills during accident scenarios, thereby improving overall operational economy, convenience, and long-term deployment feasibility.

[0005] Traditional large nuclear power unit accident handling strategies typically rely on complex operating procedures, multiple redundant systems, and immediate intervention by highly skilled operators. However, this complex system is ill-suited to the actual needs of micro-small reactors (MS Reactors): on the one hand, remote environments make it difficult to guarantee the permanent presence and rapid response of highly skilled operators; on the other hand, overly cumbersome strategies may introduce operational risks, contradicting the "near-unmanned" or "simplified operation and maintenance" goals pursued by MS Reactors. Therefore, systematically optimizing and simplifying the accident handling strategies for MS Reactors, especially gas-cooled MS Reactors, is one of the key technical challenges driving their practical application.

[0006] Most currently developed micro-reactors are based on fourth-generation nuclear energy system technologies (such as high-temperature gas-cooled reactors), and their design inherently possesses significant safety characteristics: for example, negative temperature reactivity coefficients, low power density, high-temperature resistant fuel cladding, and large heat capacity. Simultaneously, the system structure is highly simple, and passive safety systems are widely adopted (such as relying on physical principles like natural circulation cooling, gravity injection, and negative feedback mechanisms to achieve safety functions). These inherent safety characteristics, simple configuration, and passive design philosophy provide a solid physical and engineering foundation for significantly simplifying or even partially automating accident handling procedures and reducing reliance on external intervention, making the optimization of post-accident strategies not only necessary but also practically feasible.

[0007] Existing patent CN113972019A provides a method, device and electronic device for generating nuclear power plant accident handling strategies. This method only achieves static classification by merging and grouping the initiating events. It does not extract the dynamic temporal characteristics in the accident evolution, which makes the classification results unable to accurately reflect the essential differences of the accident. Safety measures need to be manually implemented and safety factor demand analysis needs to be performed, which is difficult to adapt to the needs of automated execution.

[0008] Existing patent CN117524526A provides a method, apparatus, computer equipment and storage medium for handling nuclear power plant accidents. This method selects the target mode only according to the highest accident level principle, ignoring the characteristics of extreme operating conditions and probabilistic safety indicators, which may result in the omission of low-frequency high-risk events. At the same time, the strategy reuse lacks intelligence and the direct reuse of the original strategy leads to strategy redundancy.

[0009] In summary, all the existing patents mentioned above address the operational complexity and reliance on external intervention in simplifying accident handling strategies for micro-small reactors in existing technologies. Summary of the Invention

[0010] Based on the above-mentioned technical problems, this invention proposes an accident handling strategy analysis method and system for micro-miniature stacks. The purpose is to address all accidents by applying a normalized accident handling strategy, based on the requirements of micro-miniature stack operation scenarios, the design characteristics of micro-miniature stacks, and the characteristics of accident operation response, thereby greatly simplifying the post-accident operation requirements.

[0011] To achieve the above objectives, this invention proposes a method and system for analyzing accident handling strategies for micro-miniature reactors. The specific technical solution is as follows:

[0012] An analysis method for accident handling strategies in micro-miniature stacks includes the following steps: S1. Classify the initiating accidents based on multidimensional accident characteristics; S2. Select typical accidents from each type of initiating accident and analyze them to derive the handling strategies for the typical accidents; S3. Decompose the handling strategies for each type of typical accident into operational steps. S4. Compare the operational steps of the handling strategies for various typical accidents, summarize the general operations, and analyze the judgment conditions for differentiated operations. S5. Integrate general operations and differentiated operations, and generate normalized accident handling strategies according to time sequence logic; S6. Verify the effectiveness of the incident handling strategy. If it fails to meet the standard, return to step S2 for iterative optimization until all initial incidents are covered.

[0013] Furthermore, S1 specifically includes: using time-series feature extraction technology to analyze the evolution process and time sequence of each initiating accident in the accident analysis file, and classifying the initiating accidents based on the obtained accident features; The accident characteristics include physical process characteristics, system response characteristics, severity of consequences characteristics, and time window characteristics.

[0014] Furthermore, S2 includes: selecting typical accidents from each type of initiating accident based on the degree of change of one or more key thermal-hydraulic parameters; The evolution process of the typical accidents is analyzed, and envelope analysis is performed in conjunction with the system design of micro-miniature stacks to derive the handling strategies for the typical accidents.

[0015] Furthermore, the selection of typical accidents specifically involves identifying accidents in which the rate or magnitude of change of the key thermal-hydraulic parameters exceeds a preset threshold as typical accidents for each type of initiating accident.

[0016] Furthermore, S3 includes: decomposing the operation process of the handling strategies for various typical accidents obtained in step S2 into steps, and decomposing the operation of each accident handling strategy into four stages: diagnosis, immediate action, delayed action, and retreat state.

[0017] Further, S4 includes: By comparing the immediate actions of typical accidents, we can extract common operations, identify differentiated operations and their causes and judgment conditions, and summarize the immediate actions, accident characteristics and warning signals of typical accidents in micro-small reactors. By comparing the delayed actions of typical accidents, we extract the common operations, identify the differentiated operations and their causes and judgment conditions, and summarize the delayed actions, strategy characteristics and judgment signals of typical accidents of micro-small reactors. By comparing the retreat requirements of typical accidents, we summarize the different types of retreat states and the accident characteristics and judgment signals that lead to different retreat state requirements.

[0018] Furthermore, S5 includes: using general operations as general processing strategies, selecting and executing differentiated operations based on typical symptoms or judgment signals, selecting appropriate backoff states based on accident characteristics, and arranging the timing of accident processing strategies according to the accident process to obtain a normalized accident processing strategy for the micro-relay.

[0019] Furthermore, S6 includes: using simulation verification to perform qualitative analysis on the process of operating the normalized accident handling strategy after each accident occurs according to the micro-miniature stack initiation accident list. If the accidents in the initiation accident list cannot be handled or the process parameters cannot meet the acceptance criteria, then return to step S2 for iterative optimization until the handling and mitigation requirements of all initiation accidents of the micro-miniature stack are met.

[0020] This invention also provides an accident handling strategy analysis system for micro-mini-heaps, used to implement the above-described normalized accident handling strategy analysis method for micro-mini-heaps, the system comprising: The accident classification module extracts multi-dimensional accident features by analyzing accident report files and classifies the initiating accidents based on these features. The typical accident selection module is used to screen typical accidents in each type of initiation accident, analyze the evolution process of typical accidents, and combine the system design of micro-miniature reactors to derive the handling strategies for various typical accidents. The handling strategy decomposition module is used to break down the handling strategies for various typical accidents into four stages: diagnosis, immediate action, delayed action, and retreat status, and outputs a handling strategy decomposition table. The handling strategy comparison module is used to compare and analyze the similarities and differences between different accident handling strategies, summarize the common operation combinations and delayed action pattern groupings, construct a decision tree to locate the root cause of the operational differences, and output a comparative analysis report. The processing strategy normalization module is used to integrate and optimize processing strategies, solidify general operations as basic strategies, attach differentiated operations to corresponding symptom signals, and arrange the action execution sequence and constraints to generate normalized processing strategies. The processing strategy verification module is used to simulate accidents and execute normalized processing strategies synchronously, verify the acceptance results of process parameters in real time, automatically mark and optimize non-compliant accidents and trigger strategy reconstruction iterations, and output normalized processing strategies covering all initiating accidents.

[0021] Furthermore, the accident classification module includes: The report parsing unit is used to read the design baseline accident analysis report, probabilistic safety analysis report and system safety analysis report from the accident report database, and extract accident sequence information; The accident classification unit is used to integrate physical features, system response features, consequence severity features, and time window features using time-series feature extraction technology, and classifies the initiating accident based on the classification results.

[0022] Furthermore, the processing strategy comparison module includes: Operation mining unit is used to analyze the set of immediate actions to mine high-frequency common operation combinations; The clustering analysis unit is used to perform clustering analysis on the set of delayed actions to identify different operation pattern groups; The differential diagnosis unit is used to locate the root cause of operational differences by building analytical models.

[0023] Furthermore, the processing strategy verification module includes: Digital twin simulation unit, used to drive simulation models to simulate the evolution of an accident; The rule execution unit is used to execute the normalization strategy in real time through the rule engine.

[0024] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to execute the above-described incident handling strategy analysis method for micro-miniature heaps through the computer program.

[0025] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the above-described method for analyzing incident handling strategies for micro-miniature heaps.

[0026] The present invention also provides a computer-readable storage medium comprising a stored computer program, wherein the computer program can be executed by an electronic device to perform the above-described method for analyzing incident handling strategies for micro-miniature heaps.

[0027] Based on the above technical solution, compared with the prior art, the present invention has at least the following beneficial effects: 1. This invention proposes a normalized accident handling strategy analysis method and system for micro-small reactors (MSDs). It breaks through the complex framework of traditional nuclear power units that rely on event-oriented or symptom-oriented approaches. By constructing an integrated master operation strategy, it condenses hundreds of previously scattered accident procedures into a single logical flow, significantly reducing strategy complexity. This method simplifies the accident response process for MSDs by more than 70%, reduces reliance on the professional experience of operators, shortens the training cycle, and improves the overall economic efficiency of the power plant.

[0028] 2. This invention proposes a normalized accident handling strategy analysis method and system for micro-miniature reactors. Based on a normalized strategy architecture, the accident handling process fundamentally reduces the need for dynamic symptom judgment and manual strategy switching. Through a smart mapping mechanism that solidifies general operations and differentiated branches, it provides a complete technical path for automated execution. This design can directly interface with digital control systems, achieving autonomous response across the entire chain from diagnosis to retreat, laying a core safety foundation for unattended miniature reactors.

[0029] 3. This invention proposes a normalized accident handling strategy analysis method and system for micro-miniature reactors. The normalized strategy significantly simplifies the decision-making burden of operators through clear operational phase divisions and timing constraint design. The diagnostic phase clarifies the entry signals, and the action phase pre-sets the execution logic. The standardized process ensures accurate execution of key actions within the golden response period for accidents.

[0030] 4. The present invention proposes a normalized accident handling strategy analysis method and system for micro-miniature reactors. Through physical simulation and rule engine, the adaptability of the handling strategy to all initial scenarios can be verified, thereby increasing the coverage of micro-miniature reactor accident handling strategies to nearly 100%, eliminating blind spots in traditional manual analysis, and providing support for the safety certification of new nuclear energy systems. Attached Figure Description

[0031] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a flowchart illustrating an accident handling strategy analysis method for micro-miniature reactors proposed in this invention. Figure 2 This is a schematic diagram of the framework of an accident handling strategy analysis system for micro-miniature stacks proposed in this invention. Figure 3 This is a schematic diagram of an electronic device proposed in this invention. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] The present invention will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed by the present invention.

[0034] To address the operational complexity and reliance on external intervention in simplifying accident handling strategies for micro-small reactors in existing technologies, this invention proposes an accident handling strategy analysis method for micro-small reactors. Applying this method, an integrated event-based master operation strategy is formed, which greatly simplifies the accident handling strategy for micro-small reactors, reduces the professional requirements for operators, and improves operational economy.

[0035] The present invention will now be described with reference to specific embodiments.

[0036] Example 1

[0037] See Figure 1 As shown in the figure, this embodiment provides a normalized accident handling strategy analysis method for micro-miniature stacks, which includes the following steps: S1. Classify the initiating accidents based on multidimensional accident characteristics; S2. Select typical accidents from each type of initiating accident and analyze them to derive the handling strategies for the typical accidents; S3. Decompose the handling strategies for each type of typical accident into operational steps. S4. Compare the operational steps of the handling strategies for various typical accidents, summarize the general operations, and analyze the judgment conditions for differentiated operations. S5. Integrate general operations and differentiated operations, and generate normalized accident handling strategies according to time sequence logic; S6. Verify the effectiveness of the incident handling strategy. If it fails to meet the standard, return to step S2 for iterative optimization until all initial incidents are covered.

[0038] Specifically, step S1 above includes: By referring to relevant accident analysis documents, including the list of initiating accidents, probabilistic safety analysis reports, and system safety analysis reports, the evolution process and timing of each initiating accident are analyzed. Based on the accident characteristics obtained, the initiating accidents are classified. The accident characteristics include: physical process characteristics, such as coolant loss rate and pressure change gradient; and system response characteristics, such as protection system trigger time.

[0039] In a specific implementation process, for example, the classification of an initiation accident in a microreactor is as follows: ① Emergency shutdown (including reactive accidents): Initiating accidents that cause a significant increase in reactivity, such as misinsertion of control rods, misinsertion of control rods, or loss of control rod synchronism. ② Main circuit pressure loss accident: The initial accident caused by pressure drop is caused by leakage of hot gas duct shell, accidental opening of main circuit safety valve combined with air intrusion control failure, and simultaneous rupture of hot gas duct and shell; ③ Main circuit cooling cycle abnormality accident: Accidents such as the main circuit safety valve being opened by mistake, the blades of the helium turbine or compressor being damaged, or the rotor of the helium turbine or compressor being stuck, which lead to a reduction in coolant flow; ④ Heat sink malfunction: Accidents such as rupture of circulating water pipes, increased speed of circulating pumps and circulating water flow control valve stuck in the fully open position, which lead to a reduction in the heat dissipation capacity of the secondary circuit; ⑤ Main circuit water ingress accident: Accidents such as rupture of the heat transfer part of the regenerator or the heat transfer part of the intercooler leading to increased humidity in the main circuit; ⑥ATWS accident: A composite accident in which the protection signal is triggered but the reactor fails due to the accidental insertion of the control rod and the failure of the emergency shutdown, or the failure of the emergency shutdown due to the loss of external load.

[0040] Specifically, step S2 above includes: Based on the accident classification, accidents with more drastic changes in accident characteristic parameters and more severe consequences are selected as typical accidents in each category. By analyzing the accident evolution process of typical accidents and combining it with the system design of micro-miniature reactors, the handling strategies for each type of typical accident are derived.

[0041] In a specific implementation process, the selection criteria for typical accidents are those where the rate or magnitude of change of key parameters exceeds a preset threshold. This threshold is determined through statistical analysis of similar accidents, aiming to screen out the most severe and rapidly progressing conditions. Subsequently, by analyzing the evolution of these typical accidents and combining the system design and thermal-hydraulic simulation of the micro-reactor, the handling strategies for various typical accidents are finally derived.

[0042] Specifically, step S3 above includes: Based on the handling strategies for various typical accidents derived in step S2 above, the operations are broken down. An accident handling strategy is divided into four parts: diagnosis, immediate action, delayed action, and retreat state. "Diagnosis" guides operators through the inspection and judgment process of specific accident handling guidelines, generally using specific phenomena and signals of an accident as the entry conditions for the guidelines. "Immediate action" is the initial inspection and operation of the accident handling guidelines, including automatic action checks and emergency action operations. "Delayed action" is the main body of accident handling, including stabilizing the unit, accident response, retreating to a safe state, and necessary unit recovery operations. "Retreat state" is the ultimate goal of the accident handling strategy, which can also be described as the state of exiting the accident handling strategy or the reactor state at the end of the delayed action. Different retreat states are determined based on the location, equipment, and cause of the accident to facilitate maintenance work on the faulty equipment.

[0043] In a specific implementation process, the operational strategy for handling reactive accidents is divided into: Immediate actions include confirming an abnormal power range signal to trigger reactor protection shutdown, confirming an emergency shutdown signal to cause an emergency shutdown of the helium turbine, and confirming that the energy management system automatically switches to supply power to all systems of the unit from the energy storage system. Delayed actions include confirming the passive exhaust system to operate naturally, and if a rapid retreat to a lower state is required, restarting the helium turbine for forced cooling. Retreat state includes natural cooling in a cold state.

[0044] For main circuit cooling cycle anomaly accidents, heat sink anomaly accidents, and ATWS accidents, there are no particularly special procedures. The handling strategies can be divided into: Immediate actions include confirming the corresponding protection signal triggering reactor protection shutdown, confirming the emergency shutdown signal causing an emergency shutdown of the helium turbine, and confirming the energy management system automatically switches to supplying power to all unit systems from the energy storage system. Delayed actions include confirming the passive residual exhaust system operates naturally; if a rapid retreat to a lower state is required, the helium turbine can be restarted for forced cooling. The retreat state includes natural cooling from a cold state. The handling strategies are basically the same as for reactive accidents.

[0045] The operational strategy for handling a main circuit depressurization accident is divided into the following steps: Immediate actions include confirming a high negative rate of change in main circuit pressure, high outlet temperature, or low main circuit pressure to trigger an emergency reactor shutdown; confirming an emergency shutdown signal to cause an emergency shutdown of the helium turbine; and confirming that the energy management system automatically switches to supply power to all unit systems from the energy storage system. Delayed actions include confirming the passive exhaust system operates naturally; and, if necessary, activating the helium charging and venting system to pressurize the main circuit slightly to prevent air from entering the reactor core. The retreat phase includes natural cooling in a cold state.

[0046] The operational strategy for handling a main circuit water ingress accident is divided into the following steps: Immediate actions include confirming a high humidity signal in the main circuit triggering an emergency reactor shutdown, confirming an emergency shutdown signal causing an emergency shutdown of the helium turbine, confirming that the energy management system automatically switches to supplying power to all unit systems from the energy storage system, and confirming that the isolation valves on the precooler branch are closed. Delayed actions include confirming that the passive exhaust system operates naturally. A fallback state includes natural cooling in a cold state. Based on the above analysis, a typical accident handling strategy analysis table is obtained.

[0047] Specifically, step S4 above includes: Based on the typical accident handling strategy analysis table, the "immediate actions" for various typical accidents in the table are compared and summarized. The general operations of the "immediate actions" in the handling strategies of various typical accidents are summarized, and the differentiated operations, the reasons for the differentiated operations, and the judgment conditions are found. Finally, the immediate actions, accident characteristics, and symptom signals of various typical accidents of micro-small reactors are summarized.

[0048] In a specific implementation process, the common "immediate action" procedures in handling typical accidents of micro-small reactors mainly involve automatic action checks and confirmations, including: confirming emergency shutdown, confirming emergency shutdown, and confirming automatic switching of the energy management system. In addition, different accidents involve specific other operations, i.e., differentiated operations. For example, the main cause of a main circuit depressurization accident is leakage, rupture, or accidental opening of equipment components in contact with radioactive coolant in the main circuit, all of which can lead to the release of radioactive materials. Therefore, once such an accident occurs, after confirming shutdown, it is also necessary to confirm isolation from the helium charging and venting system. The main cause of a main circuit water ingress accident is the rupture of heat transfer components related to the main circuit in the heat sink system, causing circulating water from the heat sink system to enter the main circuit, affecting normal unit operation. Once such an accident occurs, after confirming shutdown as quickly as possible, it is also necessary to isolate the branches related to the heat sink to reduce the ingress of circulating water into the heat sink. The main reason for the failure to shut down the expected transient accident is the failure to shut down the reactor in time after the accident, such as the shutdown rods getting stuck. The gas-cooled miniature reactor system is designed with two independent shutdown systems. When the normal shutdown system fails and cannot operate normally, the second shutdown system needs to be manually activated (manually inserting the center rod group) to ensure that the reactor can reach a safe shutdown state.

[0049] Based on the typical accident handling strategy analysis table, the "delayed actions" for various typical accidents in the table are compared and summarized. The common operations of "delayed actions" in the handling strategies of various typical accidents are summarized, and the differentiated operations, their causes, and judgment conditions are identified. Finally, the delayed actions, accident strategy characteristics, and judgment signals for various typical accidents in micro-reactors are summarized. After the "immediate action" handling of the accident, the reactor will tend to be stable and safe. To ensure the safety of the reactor and main circuit, and to reduce the impact of transients on system equipment, the accident handling at this time mainly involves optimal recovery operations, including adjustments to system operation, protection of some system equipment, and coordinated operation of auxiliary systems. To facilitate subsequent recovery and maintenance, the unit needs to be withdrawn to the required mode. Withdrawal can be achieved using helium turbine forced cooling or passive exhaust system natural cooling. For some accidents, such as helium turbine and compressor rotor jamming, or loss of heat sinks, the helium turbine cannot be started after the accident, and only passive exhaust system cooling can be relied upon to achieve and maintain a cold shutdown. Based on the possible process, subsequent mitigation actions can be divided into three types: ① restarting the helium turbine, forcibly cooling, retreating to a cold shutdown, and repairing damaged equipment; ② waiting in a safe shutdown state, cooling to a cold shutdown state through a passive residual discharge system, and then repairing damaged equipment; ③ maintaining the current shutdown state.

[0050] Based on the analysis table of typical accident handling strategies, the "retreat state requirements" of various types of typical accidents in the table are compared, and the characteristics and judgment signals of different types of retreat states and the accidents that lead to different retreat state requirements are summarized.

[0051] Based on the operating conditions of gas-cooled miniature reactors (MSRs), there are generally three retreat states for accident handling, corresponding to the states required for reactor safety and fault recovery: cold shutdown, hot shutdown, and maintaining the current state. If the accident occurs in the main circuit or core-related systems of the gas-cooled MSR, the reactor needs to be retreated to cold shutdown after confirming the shutdown to allow the main circuit to be opened and the faulty equipment to be repaired. If the accident occurs in a non-main circuit or non-core-related system of the gas-cooled MSR, but the faulty equipment will affect the safe operation of the reactor, the reactor needs to be retreated to hot shutdown after confirming the shutdown to allow for the repair of the faulty equipment.

[0052] Specifically, step S5 above includes: Based on the summary results of step S4 above, further comprehensive analysis is conducted, mainly analyzing the universality and differences of various typical accident handling strategies, as well as the logical relationships and levels of accident handling. Common operations are designated as universal handling strategies, while differentiated operations are selected and executed based on typical symptoms or judgment signals. Simultaneously, appropriate retreat states are selected according to accident characteristics. Following the accident progression, the timing of accident handling strategies is rationally arranged to obtain a normalized accident handling strategy encompassing the small reactor accident.

[0053] In a specific implementation process, the normalized accident handling strategy obtained from the analysis is shown in Table 1 below: Table 1: Normalized Accident Handling Strategy for Micro-Small Reactor Accidents

[0054] Specifically, step S6 above includes: The normalized accident handling strategy is validated through simulation. Qualitative simulation analysis is performed on the evolution of the normalized accident handling strategy after each accident occurs, according to the micro-mini-relay initiation accident list, to confirm whether the normalized accident handling strategy can handle all accidents in the initiation accident list. If it does not meet the requirements, the process returns to step S2 for modification until the obtained normalized accident handling strategy meets the requirements for handling and mitigating all initiation accidents of the micro-mini-relay.

[0055] In a specific implementation process, a simulation modeling platform (such as MWORKS, RELAP5, etc.) is used to conduct full-coverage simulation verification according to the list of initiating accidents of the micro-miniature reactor. The acceptance criterion is that the highest core temperature does not exceed 1600℃. If the requirement is not met, the characteristic parameters of the non-compliant accident are marked, and the process returns to step S2 to expand the typical accident library and reconstruct the handling strategy until the obtained normalized accident handling strategy meets the handling and mitigation requirements of all initiating accidents of the micro-miniature reactor.

[0056] Example 2

[0057] See Figure 2 As shown in the figure, this embodiment provides an accident handling strategy analysis system for micro-miniature reactors. The system sequentially includes an initiation accident classification module, a typical accident selection module, a handling strategy decomposition module, a handling strategy comparison module, a handling strategy normalization module, and a handling strategy verification module.

[0058] The accident classification module includes a report parsing unit and an accident classification unit. The report parsing unit reads documents such as design baseline accident analysis reports, probabilistic safety analysis reports, and system safety analysis reports stored in a database or file server, and extracts the accident sequence information described therein. The core operation of the accident classification unit is to apply a time-series feature extraction algorithm to analyze the accident evolution process, identify and integrate key physical features, system response features, consequence severity features, and time window features. Based on a trained classification model, this unit automatically classifies the initiating accident into a preset standard accident type.

[0059] The typical accident selection module includes a feature distribution calculation unit, a high-consequence screening unit, and a list generation unit. The feature distribution calculation unit, for each type of initiating accident, calls historical or simulated data from the database to calculate the rate of change distribution of its key characteristic parameters. The high-consequence screening unit queries the probabilistic safety analysis database to filter out high-risk accident cases. The list generation unit combines the results of the first two units—that is, those with the highest rate of change or magnitude of change in that type of accident—to generate a typical accident list. This list records the path to the high-fidelity simulation model file corresponding to each typical accident, integrates the design parameters of the micro-miniature reactor-specific passive safety system extracted from the design parameter database, and ultimately constructs a set of typical accident handling strategies.

[0060] The handling strategy decomposition module includes a text parsing unit and a strategy decomposition unit. The text parsing unit uses natural language processing technology to analyze typical accident handling strategy texts. Based on the parsing results, the strategy decomposition unit intelligently decomposes the complex strategy text into four standardized stages: the diagnosis stage identifies and extracts the guiding entry signal features required to initiate the strategy; the immediate action stage identifies and extracts the operation instructions executed by the automatic protection system; the delayed action stage parses and extracts the system recovery operations that require manual operation by the operator and their triggering conditions; and the retreat state stage maps and confirms the target safety state that the accident handling ultimately needs to achieve. This module ultimately outputs a handling strategy decomposition table, clearly defining the operation content, execution conditions, and key parameter thresholds for each stage, stored in a database or file system.

[0061] The handling strategy comparison module includes an operation mining unit, a clustering analysis unit, and a difference diagnosis unit. The operation mining unit applies the Apriori association rule mining algorithm to the immediate action sets from different typical accident handling strategies to identify frequently occurring operation combinations, such as common operations like reactor shutdown confirmation and emergency power switching. The clustering analysis unit similarly uses the K-means clustering algorithm on the delayed action sets, grouping them according to operation content and conditions, for example, identifying operation clusters that primarily rely on natural cooling and those requiring forced cooling. The difference diagnosis unit constructs an accident symptom-differentiated operation decision tree model to analyze the root causes of operational differences between different accident handling strategies, i.e., specific symptom signals or operating conditions. This module ultimately generates a comparative analysis report, clearly listing the common operation set, differentiated operation branches, and their corresponding judgment conditions.

[0062] The normalization module for handling incidents comprises a strategy integration unit and a timing orchestration unit. The strategy integration unit solidifies high-frequency, general operations obtained from comparative analysis into a basic strategy layer. Based on rules revealed by the decision tree model, it assigns differentiated operations to their corresponding specific incident symptom signal nodes. The timing orchestration unit utilizes timing modeling tools such as Petri nets to rigorously orchestrate the execution sequence and logical dependencies of all actions. It enforces constraints on key timing requirements and activates delayed actions in stages based on set process parameter thresholds such as temperature, while ensuring that the execution result of the entire action sequence dynamically matches the final retreat state target. This module ultimately outputs a normalized incident handling strategy for mini-heaps, optimized and orchestrated through integration, and stored in the form of structured data or configuration files.

[0063] The processing strategy verification module comprises a digital twin simulation unit, a rule execution unit, and a closed-loop optimization unit. The digital twin simulation unit drives a high-fidelity thermal-hydraulic simulation model, simulating the complete evolution of all accidents in the typical accident list. The rule execution unit loads the normalized processing strategy into the Drools rule engine, executing the rules and operational instructions in the strategy in real time during simulation. The closed-loop optimization unit monitors key safety indicators in the simulation output in real time, such as calculating the core damage frequency (CDF) value. For accident cases that fail to meet preset safety targets, this unit automatically analyzes and marks the key characteristic parameters leading to the problem, generates detailed optimization work orders, triggers a strategy refactoring process, feeds back defective accident cases to the typical accident library for expansion, and initiates a new round of processing strategy generation iterations. Finally, this module outputs a fully validated and iteratively optimized normalized processing strategy covering all initiating accident types.

[0064] The system can automate the entire process from "accident input" to "strategy output", with human involvement only required in the initial configuration and final acceptance stages.

[0065] Example 3

[0066] This embodiment provides an electronic device, and this embodiment uses the electronic device as a terminal device as an example for illustration. For example... Figure 3 As shown, the electronic device includes a memory 302 and a processor 304. The memory 302 stores a computer program, and the processor 304 is configured to execute the steps of the accident handling strategy analysis method for micro-small stacks in Embodiment 1 above through the computer program.

[0067] Optionally, in this embodiment, the aforementioned electronic device may be located in at least one of a plurality of network devices in a computer network.

[0068] Alternatively, as those skilled in the art will understand, Figure 3 The structure shown is for illustrative purposes only. Figure 3 This does not limit the structure of the aforementioned electronic devices. For example, the electronic device may also include components that are more... Figure 3 The more or fewer components shown (such as network interfaces, etc.), or having the same Figure 3 The different configurations shown.

[0069] The memory 302 can be used to store software programs and modules, such as the program instructions / modules corresponding to the method in Embodiment 1 of this application. The processor 304 executes various functional applications and data processing by running the software programs and modules stored in the memory 302, thereby implementing the accident handling strategy analysis method for micro-small heaps in Embodiment 1. The memory 302 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 302 may further include memory remotely located relative to the processor 304, and these remote memories can be connected to the terminal via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof. Specifically, the memory 302 may be used, but is not limited to, for storing data information. As an example, such as Figure 3 As shown, the memory 302 may include, but is not limited to, the initiation accident classification module, typical accident selection module, processing strategy decomposition module, processing strategy comparison module, processing strategy normalization module, and processing strategy verification module of the above system. Furthermore, it may include, but is not limited to, other module units in the above device, which will not be elaborated upon in this example.

[0070] Optionally, the aforementioned electronic device further includes a transmission device 306 for receiving or sending data via a network. Specific examples of the network described above may include wired and wireless networks. In one example, the transmission device 306 includes a Network Interface Controller (NIC), which can be connected to other network devices and a router via a network cable to communicate with the Internet or a local area network. In another example, the transmission device 306 is a radio frequency (RF) module used for wireless communication with the Internet.

[0071] In addition, the above-mentioned electronic device also includes a display 308 and a connection bus 310, which is used to connect the various module components in the above-mentioned electronic device.

[0072] Example 4

[0073] This embodiment provides a computer program product, which includes a computer program that is executed by an electronic device to perform the incident handling strategy analysis method for micro-miniature heaps in Embodiment 1.

[0074] Example 5

[0075] This embodiment provides a computer-readable storage medium from which the processor of an electronic device reads computer instructions. The processor executes the computer instructions, causing the electronic device to perform the accident handling strategy analysis method for micro-miniature stacks described in Embodiment 1 above.

[0076] Optionally, in this embodiment, the computer-readable storage medium may be configured to store the incident handling strategy analysis method for micro-miniature heaps in Embodiment 1 of this application.

[0077] Optionally, in this embodiment, those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing the hardware related to the terminal device. The program can be stored in a computer-readable storage medium, which may include: flash drive, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0078] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0079] 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 one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0080] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus or device (such as a computer-based system, a processor-included system or other system that can fetch and execute instructions from, an instruction execution system, apparatus or device).

[0081] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0082] It should be noted that, in the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. A method for analyzing accident handling strategies for micro-miniature reactors, characterized in that, Includes the following steps: S1. Classify the initiating accidents based on multidimensional accident characteristics; S2. Select typical accidents from each type of initiating accident and analyze them to derive the handling strategies for the typical accidents; S3. Decompose the handling strategies for each type of typical accident into operational steps. S4. Compare the operational steps of the handling strategies for various typical accidents, summarize the general operations, and analyze the judgment conditions for differentiated operations. S5. Integrate general operations and differentiated operations, and generate normalized accident handling strategies according to time sequence logic; S6. Verify the effectiveness of the incident handling strategy. If it fails to meet the standard, return to step S2 for iterative optimization until all initial incidents are covered.

2. The accident handling strategy analysis method for micro-miniature reactors according to claim 1, characterized in that, S1 specifically includes: using time-series feature extraction technology to analyze the evolution process and time sequence of each initiating accident in the accident analysis file, and classifying the initiating accidents based on the obtained accident features; The accident characteristics include physical process characteristics, system response characteristics, severity of consequences characteristics, and time window characteristics.

3. The accident handling strategy analysis method for micro-miniature reactors according to claim 2, characterized in that, S2 includes: selecting typical accidents from each type of initiating accident based on the degree of change of one or more key thermal-hydraulic parameters; The evolution process of the typical accidents is analyzed, and envelope analysis is performed in conjunction with the system design of micro-miniature stacks to derive the handling strategies for the typical accidents.

4. The accident handling strategy analysis method for micro-miniature reactors according to claim 3, characterized in that, The selection of typical accidents specifically involves identifying accidents in which the rate or magnitude of change of the key thermal-hydraulic parameters exceeds a preset threshold as typical accidents for each type of initiating accident.

5. The accident handling strategy analysis method for micro-miniature reactors according to claim 4, characterized in that, S3 includes: decomposing the operation process of the handling strategies for various typical accidents obtained in step S2 into steps, and decomposing the operation of each accident handling strategy into four stages: diagnosis, immediate action, delayed action, and retreat state.

6. The accident handling strategy analysis method for micro-miniature reactors according to claim 5, characterized in that, S4 includes: By comparing the immediate actions of typical accidents, we can extract common operations, identify differentiated operations and their causes and judgment conditions, and summarize the immediate actions, accident characteristics and warning signals of typical accidents in micro-small reactors. By comparing the delayed actions of typical accidents, we extract the common operations, identify the differentiated operations and their causes and judgment conditions, and summarize the delayed actions, strategy characteristics and judgment signals of typical accidents of micro-small reactors. By comparing the retreat requirements of typical accidents, we summarize the different types of retreat states and the accident characteristics and judgment signals that lead to different retreat state requirements.

7. The accident handling strategy analysis method for micro-miniature reactors according to claim 6, characterized in that, S5 includes: using general operations as general processing strategies, selecting and executing differentiated operations based on typical symptoms or judgment signals, selecting appropriate backoff states based on accident characteristics, and arranging the timing of accident processing strategies according to the accident process to obtain a normalized accident processing strategy for micro-relays.

8. The accident handling strategy analysis method for micro-miniature reactors according to claim 7, characterized in that, S6 includes: using simulation verification to perform qualitative analysis on the process of operating the normalized accident handling strategy after each accident occurs according to the micro-miniature stack initiation accident list. If the accidents in the initiation accident list cannot be handled or the process parameters cannot meet the acceptance criteria, then return to step S2 for iterative optimization until the handling and mitigation requirements of all initiation accidents of the micro-miniature stack are met.

9. An accident handling strategy analysis system for micro-miniature heaps, used to implement the normalized accident handling strategy analysis method for micro-miniature heaps as described in any one of claims 1-8, characterized in that, The system comprises, in sequence: The accident classification module extracts multi-dimensional accident features by analyzing accident report files and classifies the initiating accidents based on these features. The typical accident selection module is used to screen typical accidents in each type of initiation accident, analyze the evolution process of typical accidents, and combine the system design of micro-miniature reactors to derive the handling strategies for various typical accidents. The handling strategy decomposition module is used to break down the handling strategies for various typical accidents into four stages: diagnosis, immediate action, delayed action, and retreat status, and outputs a handling strategy decomposition table. The handling strategy comparison module is used to compare and analyze the similarities and differences between different accident handling strategies, summarize the common operation combinations and delayed action pattern groupings, construct a decision tree to locate the root cause of the operational differences, and output a comparative analysis report. The processing strategy normalization module is used to integrate and optimize processing strategies, solidify general operations as basic strategies, attach differentiated operations to corresponding symptom signals, and arrange the action execution sequence and constraints to generate normalized processing strategies. The processing strategy verification module is used to simulate accidents and execute normalized processing strategies synchronously, verify the acceptance results of process parameters in real time, automatically mark and optimize non-compliant accidents and trigger strategy reconstruction iterations, and output normalized processing strategies covering all initiating accidents.

10. The accident handling strategy analysis system for micro-miniature reactors according to claim 9, characterized in that, The accident classification module includes: The report parsing unit is used to read the design baseline accident analysis report, probabilistic safety analysis report and system safety analysis report from the accident report database, and extract accident sequence information; The accident classification unit is used to integrate physical features, system response features, consequence severity features, and time window features using time-series feature extraction technology, and classifies the initiating accident based on the classification results.

11. The accident handling strategy analysis system for micro-miniature reactors according to claim 9, characterized in that, The processing strategy comparison module includes: Operation mining unit is used to analyze the set of immediate actions to mine high-frequency common operation combinations; The clustering analysis unit is used to perform clustering analysis on the set of delayed actions to identify different operation pattern groups; The differential diagnosis unit is used to locate the root cause of operational differences by building analytical models.

12. The accident handling strategy analysis system for micro-miniature stacks according to claim 9, wherein the accident handling strategy analysis system for micro-miniature stacks is characterized in that, The processing strategy verification module includes: Digital twin simulation unit, used to drive simulation models to simulate the evolution of an accident; The rule execution unit is used to execute the normalization strategy in real time through the rule engine.

13. An electronic device comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to execute, through the computer program, the accident handling strategy analysis method for micro-miniature heaps as described in any one of claims 1 to 8.

14. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the steps of the accident handling strategy analysis method for micro-miniature heaps as described in any one of claims 1 to 8.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein the computer program can be executed by an electronic device to perform the incident handling strategy analysis method for micro-miniature stacks as described in any one of claims 1 to 8.

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