Accident handling method and device for nuclear power station and terminal equipment

Abstract

The invention relates to an accident handling method and device of a nuclear power plant, terminal equipment and a computer readable storage medium, a safety function of the nuclear power plant comprises safety shell integrity, and the accident handling method of the nuclear power plant comprises the following steps: detecting whether a reactor core of the nuclear power plant is melted or not; if the reactor core melts, the priority of the containment integrity in a preset first control strategy is adjusted, a second control strategy is obtained, and in the second control strategy, the priority of the containment integrity in the safety function of the nuclear power plant is the highest, so that the containment integrity is firstly maintained after the nuclear power plant has an accident; and executing an accident handling program based on the second control strategy. According to the invention, a basis can be provided for an operator to adopt a proper accident processing program in different accident scenes of the nuclear power station, so that the accident processing of the nuclear power station is more purposeful and higher in efficiency, meanwhile, the human error probability is reduced, and the safe operation of the nuclear power station after the accident is ensured.

Description

Technical Field

[0001] The present application belongs to the field of nuclear power safety technology, and in particular, relates to a method, device, terminal equipment and computer-readable storage medium for handling accidents in a nuclear power plant. Background Art

[0002] In order to prevent the release of radioactive materials into the environment, nuclear power plants generally have multiple safety barriers. After a nuclear power plant accident occurs, if the integrity of these safety barriers is good, the radioactive materials produced by the accident can be effectively limited. For pressurized water reactor nuclear power plants, there are generally three safety barriers: fuel cladding, primary pressure boundary, and containment. For each safety barrier, its integrity is maintained by maintaining the corresponding key safety functions.

[0003] If a critical safety function is degraded, an appropriate critical safety function repair strategy needs to be implemented to repair it. Since there may be conflicts between different critical safety functions, it is necessary to define the priority of critical safety function control to deal with the situation where multiple critical safety functions are degraded at the same time.

[0004] At present, the priority of critical safety functions is often determined based on the order of safety barriers encountered when radioactive materials are released. This priority determination method gives the priority of critical safety functions that is consistent in any accident scenario. However, in different accident scenarios, considering the physical impact caused by the accident, this consistent priority of critical safety functions may not be suitable for the current accident scenario.

[0005] Currently, no effective solution has been proposed for the problem that related technologies cannot adjust the priority of safety functions according to different nuclear power plant accident scenarios. Summary of the invention

[0006] The embodiments of the present application provide a method, apparatus, terminal device and computer-readable storage medium for handling an accident in a nuclear power plant, so as to at least solve the problem in the related art that it is impossible to adjust the priority of safety functions for different nuclear power plant accident scenarios.

[0007] In a first aspect, an embodiment of the present application provides an accident handling method for a nuclear power plant, wherein the safety function of the nuclear power plant includes the integrity of the containment vessel, and the method comprises: detecting whether a core of the nuclear power plant has melted; if the core has melted, adjusting the priority of the containment vessel integrity in a preset first control strategy to obtain a second control strategy, wherein, in the second control strategy, the containment vessel integrity has the highest priority among the safety functions of the nuclear power plant to indicate that the containment vessel integrity is maintained first after an accident occurs in the nuclear power plant; and executing an accident handling procedure based on the second control strategy.

[0008] In some embodiments, the safety functions of the nuclear power plant also include primary loop integrity, heat sink and water loading. After detecting whether the core of the nuclear power plant has melted, the method also includes: if the core has not melted, determining whether the main pump of the nuclear power plant is in operation; if the main pump is in operation, detecting the subcooling of the outlet coolant of the core; if the subcooling is greater than a preset first threshold, adjusting the priority of primary loop integrity, heat sink, containment integrity and water loading in the first control strategy to obtain a third control strategy, wherein in the third control strategy, primary loop integrity has the highest priority among the safety functions of the nuclear power plant, and the priority of primary loop integrity is higher than that of heat sink, the priority of heat sink is higher than that of containment integrity, and the priority of containment integrity is higher than that of water loading; based on the third control strategy, executing the accident handling procedure.

[0009] In some embodiments, after detecting the subcooling of the outlet coolant of the core, the method further includes: if the subcooling is less than a first threshold and greater than a measurement uncertainty of the subcooling, executing an accident handling procedure based on a first control strategy.

[0010] In some embodiments, after detecting the subcooling of the outlet coolant of the core, the method further includes: if the subcooling is less than the measurement uncertainty of the subcooling, shutting down the main pump.

[0011] In some embodiments, after determining whether the main pump of the nuclear power plant is in operation, the method further includes: if the main pump is in a shutdown state, detecting the degree of subcooling of the outlet coolant of the core and the water level of the pressure vessel; if the degree of subcooling is greater than a preset second threshold and the water level is greater than a preset third threshold, adjusting the priority of the integrity of a loop, the heat sink, the integrity of the containment and the water loading in the first control strategy to obtain a third control strategy; based on the third control strategy, executing the accident handling procedure.

[0012] In some embodiments, after detecting the subcooling of the outlet coolant of the core and the water level of the pressure vessel, the method also includes: if the subcooling is less than a second threshold and greater than the measurement uncertainty of the subcooling, and the water level is greater than a third threshold, then based on the first control strategy, executing an accident handling procedure.

[0013] In some embodiments, the safety functions of the nuclear power plant also include subcriticality and core cooling. After detecting the supercooling of the outlet coolant of the core and the water level of the pressure vessel, the method also includes: if the supercooling is less than the measurement uncertainty of the supercooling and greater than the negative value of the measurement uncertainty, and the water level is greater than a third threshold, then judging whether the heat sink of the nuclear power plant is in an available state; if the heat sink is in an unavailable state, adjusting the priority of the first-loop integrity, the heat sink, the containment integrity, the water loading, the subcriticality and the core cooling in the first control strategy to obtain a fourth control strategy, wherein in the fourth control strategy, the heat sink has the highest priority in the safety functions of the nuclear power plant, and the priority of the heat sink is higher than the priority of core cooling, the priority of core cooling is higher than the priority of subcriticality, the priority of subcriticality is higher than the priority of the first-loop integrity, the priority of the first-loop integrity is higher than the priority of the containment integrity, and the priority of the containment integrity is higher than the priority of the water loading; based on the fourth control strategy, executing the accident handling procedure.

[0014] In some embodiments, after determining whether the heat sink of the nuclear power plant is in an available state, the method further includes: if the heat sink is in an available state, executing an accident handling procedure based on a first control strategy.

[0015] In some embodiments, the safety functions of the nuclear power plant also include core cooling. After detecting the subcooling of the outlet coolant of the core and the water level of the pressure vessel, the method also includes: if the subcooling is less than the negative value of the measurement uncertainty of the subcooling or the water level is less than a third threshold, then adjusting the priority of core cooling and containment integrity in the first control strategy to obtain a fifth control strategy, wherein in the fifth control strategy, core cooling has the highest priority in the safety functions of the nuclear power plant, and the priority of core cooling is higher than the priority of containment integrity; based on the fifth control strategy, executing the accident handling procedure.

[0016] In a second aspect, an embodiment of the present application provides an accident handling device for a nuclear power plant, wherein the safety functions of the nuclear power plant include containment integrity, and the accident handling device for the nuclear power plant includes: a detection module for detecting whether a core of the nuclear power plant has melted; an adjustment module for adjusting the priority of the containment integrity in a preset first control strategy when the core has melted, to obtain a second control strategy, wherein in the second control strategy, the containment integrity has the highest priority among the safety functions of the nuclear power plant, to indicate that the containment integrity is maintained first after an accident occurs in the nuclear power plant; and an execution module for executing the accident handling procedure based on the second control strategy.

[0017] In a third aspect, an embodiment of the present application provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the accident handling method for a nuclear power plant described in any one of the first aspects above is implemented.

[0018] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the accident handling method for a nuclear power plant described in any one of the first aspects above.

[0019] In a fifth aspect, an embodiment of the present application provides a computer program product, which, when executed on a terminal device, enables the terminal device to execute the accident handling method for a nuclear power plant described in any one of the above-mentioned first aspects.

[0020] Compared with the related art, the accident handling method, device, terminal equipment and computer-readable storage medium of the nuclear power plant provided in the embodiment of the present application determine the cooling state of the core by detecting whether the core of the nuclear power plant has melted, determine that a serious accident has occurred in the nuclear power plant when the core has melted, and adjust the priority of the integrity of the containment to the highest, so as to give the highest priority to maintaining the integrity of the containment as a safety barrier after the accident. Through this application, the problem that the priority of safety functions cannot be adjusted for different nuclear power plant accident scenarios in the related art is solved. By dividing the cooling state of the core and adjusting the priority of safety functions for different cooling states of the core, it can provide a basis for operators to adopt appropriate accident handling procedures in different nuclear power plant accident scenarios, making the accident handling of nuclear power plants more purposeful and efficient, while reducing the probability of human error and ensuring safe operation after nuclear power plant accidents.

[0021] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 is a flow chart of a method for handling an accident in a nuclear power plant according to an embodiment of the present application;

[0024] Figure 2is a flow chart of a method for handling an accident in a nuclear power plant according to another embodiment of the present application;

[0025] Figure 3 is a schematic diagram of a safety function priority control strategy in a main pump operating state according to an embodiment of the present application;

[0026] Figure 4 is a flow chart of a method for handling an accident in a nuclear power plant according to another embodiment of the present application;

[0027] Figure 5 is a schematic diagram of a safety function priority control strategy when the main pump is out of service according to an embodiment of the present application;

[0028] Figure 6 is a schematic diagram of an application scenario according to an embodiment of the present application;

[0029] Figure 7 It is a structural schematic diagram of an accident handling device of a nuclear power plant according to an embodiment of the present application;

[0030] Figure 8 It is a structural diagram of a terminal device according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0032] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0033] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0034] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0035] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0036] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0037] In order to prevent the release of radioactive materials into the environment, nuclear power plants generally have multiple safety barriers. After a nuclear power plant accident occurs, if the integrity of these safety barriers is good, the radioactive materials produced by the accident can be effectively limited. For pressurized water reactor nuclear power plants, three safety barriers are generally set up: fuel cladding, primary circuit pressure boundary, and containment. For each safety barrier, its integrity is maintained by maintaining the corresponding critical safety function (hereinafter referred to as safety function). The safety functions defined in a pressurized water reactor nuclear power plant and the corresponding relationship between these safety functions and safety barriers are shown in Table 1.

[0038]

[0039]

[0040] Table 1

[0041] If a safety function is degraded, it is necessary to implement an appropriate safety function repair strategy to repair it. Since there may be conflicts between different safety functions, it is necessary to define the priority of safety function control to deal with the situation where multiple safety functions are degraded at the same time. In fact, there may be conflicts between different safety functions. For example, the primary loop integrity control requires the shutdown of all potential pressurization sources including the safety injection system, while the core cooling control requires the start-up of the safety injection system. Therefore, the control of multiple safety functions must be based on the corresponding priority principle.

[0042] After a nuclear power plant accident occurs, since the first safety barrier encountered when radioactive materials are released is the fuel assembly / cladding, the safety functions related to this safety barrier are given the highest priority. The potential threat to the first safety barrier may come from inside or outside the barrier. The threat inside the barrier lies in the excessive generation of core heat due to the increase in core nuclear power. The heat generated by the core exceeds the capacity of the core heat removal system, which is the most serious threat to the first safety barrier. At the same time, if the core power is too high, the generation of energy means a potential threat to other safety barriers. Therefore, subcriticality is defined as the safety function with the highest priority. The external threat to the fuel assembly / cladding lies in the insufficient residual heat removal capacity caused by insufficient reactor coolant or secondary circuit coolant. Therefore, core cooling and heat sink are defined as the second and third priorities respectively.

[0043] For the second safety barrier, the primary pressure boundary, although the threat may come from inside or outside the barrier, only the threat from inside the barrier needs to be considered when determining the priority of the safety function (the threat from outside the barrier is beyond the operator's management scope). The internal threat to the primary pressure boundary lies in the pressurization thermal shock of the pressure vessel, which occurs when thermal stress acts on the pressure vessel embrittled by irradiation under low reactor coolant temperature conditions. Therefore, the integrity of the reactor coolant system (also called the primary loop integrity) is defined as the fourth priority.

[0044] The third safety barrier, the containment, is similar to the second safety barrier in that only the threats from within the barrier need to be considered when determining the priority of the safety functions associated with it. Similarly, the integrity of the containment is considered the fifth priority.

[0045] The sixth priority safety function is the reactor coolant charge (also called water charge). This safety function is actually a supplement to the core cooling safety function. This safety function is mainly applicable to the situation where the reactor coolant charge can meet the core cooling safety function, but exceeds the normal operating limit. Therefore, the water charge is set as the lowest priority among the six safety functions.

[0046] Therefore, the relevant technology determines the priority of key safety functions based on the order of safety barriers encountered when radioactive materials are released. This priority determination method gives the priority of safety functions that are consistent under any accident scenario. The priority order of the consistent safety functions is as follows: 1. Subcriticality; 2. Core cooling; 3. Heat sink; 4. Primary circuit integrity; 5. Containment integrity; 6. Water loading.

[0047] However, in different accident scenarios, considering the physical impact caused by the accident, the priority of this consistent safety function may not be suitable for the current accident scenario. For example, in the case of a large primary rupture accident that poses a serious threat to core cooling, since the core coolant is in the vapor phase, the existence of the cavitation effect makes subcriticality control unnecessary, and core cooling should be controlled first. If the operator handles it according to the safety function priority provided by the relevant technology, it will waste precious response time under the accident condition, causing trouble and obstacles to the operator's accident handling.

[0048] Currently, no effective solution has been proposed for the problem that related technologies cannot adjust the priority of safety functions according to different nuclear power plant accident scenarios.

[0049] In view of this, the embodiment of the present application provides an accident handling method for a nuclear power plant, which determines the cooling state of the core by detecting whether the core of the nuclear power plant has melted, determines that a serious accident has occurred in the nuclear power plant when the core has melted, and adjusts the priority of the integrity of the containment to the highest level, thereby giving the highest priority to maintaining the integrity of the containment as a safety barrier after the accident. Through this application, the problem that the priority of safety functions cannot be adjusted for different nuclear power plant accident scenarios in the related art is solved. By dividing the cooling state of the core and adjusting the priority of safety functions for different cooling states of the core, it can provide a basis for operators to adopt appropriate accident handling procedures in different nuclear power plant accident scenarios, making the accident handling of nuclear power plants more purposeful and efficient, while reducing the probability of human error and ensuring safe operation after nuclear power plant accidents.

[0050] The following will be combined Figure 1 For an explanation of a method for handling an accident in a nuclear power plant provided by an embodiment of the present application, see Figure 1 , Figure 1 is a flow chart of a method for handling an accident in a nuclear power plant according to an embodiment of the present application, such as Figure 1 As shown, the method includes:

[0051] Step S101, detecting whether the core of the nuclear power plant has melted.

[0052] In one embodiment, the nuclear power plant may be a pressurized water reactor nuclear power plant. In other embodiments, the accident handling method for a nuclear power plant provided in this embodiment may also be applied to other types of nuclear power plants, such as a boiling water reactor nuclear power plant, a heavy water reactor nuclear power plant, and a graphite gas-cooled reactor nuclear power plant.

[0053] In one embodiment, the safety function of the nuclear power plant includes at least containment integrity. Specifically, the safety function of the nuclear power plant may include one or more of containment integrity, subcriticality, core cooling, heat sink, primary loop integrity, and water loading.

[0054] In one embodiment, whether the nuclear power plant accident has transitioned to a severe accident can be determined by detecting whether the nuclear power plant core has melted. When it is detected that the nuclear power plant core has melted, it is determined that the nuclear power plant accident has transitioned to a severe accident.

[0055] In one embodiment, the core outlet temperature, the containment metering rate, and the containment spray operation status may be obtained, and based on the above parameters, it is determined whether the core has melted.

[0056] Specifically, if the core outlet temperature exceeds 650°C, or the containment dose rate exceeds 10 GY / h when the containment spray is in operation, or the containment dose rate exceeds 50 GY / h when the containment spray is not in operation, it can be considered that the core has melted and the nuclear power plant accident has transitioned to a severe accident.

[0057] Step S102, if the core melts, the priority of the containment integrity in the preset first control strategy is adjusted to obtain a second control strategy, wherein in the second control strategy, the containment integrity has the highest priority among the safety functions of the nuclear power plant, indicating that the containment integrity is maintained first after an accident occurs in the nuclear power plant.

[0058] The containment is the third safety barrier of a nuclear power plant. Before a nuclear power plant accident develops into a serious accident, the integrity of the containment is often given a lower priority. This is because before a nuclear power plant accident develops into a serious accident, the purpose of accident handling is to prevent (or delay) core melting. However, when a nuclear power plant accident has developed into a serious accident, that is, when the core melts, it generally means that the first and second safety barriers have been lost. At this time, ensuring the integrity of the containment will become the primary goal. Therefore, in the priority control strategy of the safety function of a serious accident, the priority of the containment integrity needs to be adjusted to the highest among the safety functions of the nuclear power plant, to indicate that the integrity of the containment is maintained first after an accident occurs in the nuclear power plant.

[0059] In one embodiment, the preset first control strategy includes priorities of multiple safety functions, and the priorities of the multiple safety functions can be arranged in the following order: 1. subcriticality; 2. core cooling; 3. heat sink; 4. primary loop integrity; 5. containment integrity; 6. water loading.

[0060] Specifically, in the first control strategy, subcriticality has the highest priority, core cooling has a priority second only to subcriticality, heat sink has a priority lower than core cooling and higher than primary loop integrity, and containment integrity has a priority lower than primary loop integrity and higher than water loading.

[0061] In other embodiments, the first control strategy may be changed according to the type and actual operating conditions of the nuclear power plant to which the accident handling method for a nuclear power plant provided in the embodiment of the present application is to be applied, and the present application does not limit this.

[0062] In one embodiment, the second control strategy may not include the priority of other safety functions, but only include the priority of containment integrity, thereby indicating that containment integrity should be maintained first after an accident occurs in a nuclear power plant.

[0063] In other embodiments, the second control strategy may also include the priority of one or more safety functions among the multiple safety functions as above, but the priority of containment integrity is always the highest among the multiple safety functions included in the second control strategy.

[0064] Step S103: executing the accident handling procedure based on the second control strategy.

[0065] In one embodiment, after the core melt is detected, the priority of the containment integrity in the first control strategy is adjusted to obtain the second control strategy, so that the priority of the containment integrity is the highest among the multiple safety functions included in the second control strategy. After obtaining the second control strategy, the accident handling procedure can be executed according to the second control strategy, and the accident handling procedure will maintain the highest priority goal of the containment integrity.

[0066] Specifically, the accident handling procedure can use the safety injection system, the containment spray system and the steam generator auxiliary water supply system to directly or indirectly control the temperature and pressure of the containment. In other embodiments, the accident handling procedure can be changed according to the type and actual working conditions of the nuclear power plant to which the accident handling method of the nuclear power plant provided in the embodiment of the present application is to be applied, and the present application does not limit it here.

[0067] Through the above steps S101 to S103, the cooling state of the core is determined by detecting whether the core of the nuclear power plant has melted. When the core melts, it is determined that a serious accident has occurred in the nuclear power plant, and the priority of the integrity of the containment is adjusted to the highest, so as to give the highest priority to maintaining the integrity of the containment as a safety barrier after the accident. Through this application, the problem that the priority of safety functions cannot be adjusted for different nuclear power plant accident scenarios in the related technology is solved. By dividing the cooling state of the core and adjusting the priority of safety functions for different cooling states of the core, it can provide a basis for operators to adopt appropriate accident handling procedures in different nuclear power plant accident scenarios, making the accident handling of nuclear power plants more purposeful and efficient, while reducing the probability of human error and ensuring safe operation after nuclear power plant accidents.

[0068] The following will be combined Figure 2 Another embodiment of the present invention provides a method for handling an accident in a nuclear power plant. Figure 2 , Figure 2 is a flow chart of a method for handling an accident in a nuclear power plant according to another embodiment of the present application, such as Figure 2 As shown, in another embodiment of the present application, after step S101, the method further includes steps S201 to S204:

[0069] Step S201: If the core has not melted, it is determined whether the main pump of the nuclear power plant is in operation.

[0070] In the safety control of a nuclear power plant, the operating state of the main pump has a great influence on the core cooling. When the main pump is in operation, the primary coolant can be regarded as a uniformly turbid state, and the core coolant exists in the form of a vapor-liquid two-phase mixture, and there is no obvious vapor-liquid interface. When the main pump is in a shutdown state, the core coolant vapor-liquid two-phase separation. Therefore, the accident handling method of a nuclear power plant provided in another embodiment of the present application can adjust the priority of the safety function according to the operating state of the main pump.

[0071] Step S202: If the main pump is in operation, the subcooling degree of the outlet coolant of the core is detected.

[0072] In one embodiment, when the main pump is in operation, the priority of the safety function can be adjusted according to the safety function priority control strategy in the main pump operation state. Figure 3 , Figure 3 It is a schematic diagram of a safety function priority control strategy when the main pump is in operation according to an embodiment of the present application.

[0073] like Figure 3As shown, when the main pump is in operation, the supercooling of the outlet coolant of the core (abbreviated as ΔTsat) can be detected, and the priority of the safety function can be adjusted by comparing the size relationship between ΔTsat and a preset first threshold (abbreviated as SS1) and the measurement uncertainty of ΔTsat (abbreviated as ε).

[0074] Step S203, if the degree of subcooling is greater than a preset first threshold value, the priorities of the primary loop integrity, heat sink, containment integrity and water loading in the first control strategy are adjusted to obtain a third control strategy, wherein in the third control strategy, the primary loop integrity has the highest priority in the safety functions of the nuclear power plant, and the priority of the primary loop integrity is higher than the priority of the heat sink, the priority of the heat sink is higher than the priority of the containment integrity, and the priority of the containment integrity is higher than the priority of the water loading.

[0075] In one embodiment, SS1 can be determined based on the thermal stress risk of the primary system equipment of the primary circuit (including but not limited to the surge pipe of the pressurizer and the pressure vessel) in the operating state of the main pump, and can typically be 180° C. In other embodiments, the first threshold value can be changed according to the type and actual working conditions of the nuclear power plant to which the accident handling method of the nuclear power plant is to be applied, and the present application does not limit this.

[0076] like Figure 3 As shown, in Figure 3 In region 1, ΔTsat>SS1, in which the primary circuit main system equipment may be in danger of thermal stress. At this time, it is necessary to reduce the primary circuit pressure as soon as possible to reduce ΔTsat. Therefore, in region 1, there is no need to pay attention to subcriticality and core cooling, and it is necessary to adjust the priority of primary circuit integrity, heat sink, containment integrity and water loading in the first control strategy to obtain a third control strategy, in which the primary circuit integrity has the highest priority in the safety functions of the nuclear power plant, and the priority of primary circuit integrity is higher than that of heat sink, the priority of heat sink is higher than that of containment integrity, and the priority of containment integrity is higher than that of water loading.

[0077] Step S204: executing the accident handling procedure based on the third control strategy.

[0078] In one embodiment, in addition to detecting whether the core of the nuclear power plant is melted, it is also possible to detect whether the main pump of the nuclear power plant is in operation, and adjust the priority of the safety function based on the cooling state of the core and the operating state of the main pump.

[0079] Specifically, when it is detected that the reactor core has melted, a severe accident safety function priority control strategy is adopted, that is, the priority of the containment integrity is adjusted to the highest; when it is detected that the reactor core has not melted and the main pump is in the operating state, a safety function priority control strategy under the operating state of the main pump is adopted to adjust the priority of the safety function, so as to be able to guide the operator to timely change the control strategy for the safety function at different stages of accident handling.

[0080] Please continue to refer to Figure 2 , such as Figure 2 shown, in another embodiment of the present application, after step S201, the method further includes steps S205 and S206:

[0081] Step S205, if the subcooling degree is less than the first threshold and greater than the measurement uncertainty of the subcooling degree, then based on the first control strategy, execute the accident handling procedure.

[0082] Please refer to Figure 3 , in Figure 3 region 2 of, ε < ΔTsat < SS1, in this region, the coolant in the primary loop is in the subcooled state, and the unit state is relatively stable, and the first control strategy can continue to be used to execute the accident handling procedure.

[0083] Step S206, if the subcooling degree is less than the measurement uncertainty of the subcooling degree, then shut down the main pump.

[0084] Please refer to Figure 3 , in Figure 3 region 3 of, ΔTsat < ε, in this region, the coolant in the primary loop has degraded to the saturated state, and in this working condition, it is necessary to shut down the main pump as soon as possible to separate the two phases of the coolant in the primary loop, limit the liquid phase discharge time through the break, and avoid further loss of coolant, which is very critical for accident mitigation. Therefore, in region 3, the primary task is to confirm the shutdown of the main pump as soon as possible. Once the main pump has been shut down, the priority of the safety function will be adjusted according to the safety function priority control strategy under the shutdown state of the main pump.

[0085] Next, the accident handling method of the nuclear power plant provided by another embodiment of the present application will be described in conjunction with Figure 4 Please refer to Figure 4 , such as Figure 4 shown, in another embodiment of the present application, after step S201, the method further includes steps S407 to S409:

[0086] Step S407, if the main pump is in the shutdown state, then detect the subcooling degree of the outlet coolant of the reactor core and the water level of the pressure vessel.

[0087] In one embodiment, when the main pump is in a stopped state, the priority of the safety function can be adjusted according to the safety function priority control strategy in the main pump stopped state, see Figure 5 , Figure 5 It is a schematic diagram of a safety function priority control strategy when the main pump is stopped according to an embodiment of the present application.

[0088] like Figure 5 As shown, when the main pump is in a shutdown state, ΔTsat and the pressure vessel water level (ReactorPressure Vessel water Level, RPVL) can be detected, and the priority of the safety function can be adjusted by comparing the size relationship between ΔTsat and a preset second threshold (abbreviated as SS2) and ε, and by comparing the size relationship between RPVL and a preset third threshold (abbreviated as SS3).

[0089] Step S408, if the degree of subcooling is greater than the preset second threshold and the water level is greater than the preset third threshold, the priority of the primary loop integrity, heat sink, containment integrity and water loading in the first control strategy is adjusted to obtain the third control strategy.

[0090] In one embodiment, SS2 can be determined based on the thermal stress risk of the primary system equipment of the primary circuit (including but not limited to the surge pipe of the pressurizer and the pressure vessel) when the main pump is out of service, and can typically be 140° C. In other embodiments, the second threshold value can be changed according to the type and actual working conditions of the nuclear power plant to which the accident handling method of the nuclear power plant is to be applied, and the present application does not limit this.

[0091] In one embodiment, SS3 may represent the water level of the pressure vessel that will seriously threaten the core cooling when the main pump is out of service, and may typically be the water level at the bottom of the hot leg (BHL), the water level at the top of the core (ToC), etc. In other embodiments, the third threshold value may be changed according to the type and actual working conditions of the nuclear power plant to which the accident handling method of the nuclear power plant is to be applied, and the present application does not limit this.

[0092] See also Figure 5 ,exist Figure 5 In region 1, ΔTsat>SS2 and RPVL>SS3, with Figure 3 Similar to region 1, Figure 5 In area 1, the primary circuit main system equipment may also be in danger of thermal stress. At this time, it is necessary to reduce the primary circuit pressure as soon as possible to reduce ΔTsat. Figure 5In region 1, the subcriticality and core cooling do not need to be concerned about. It is necessary to adjust the priorities of primary loop integrity, heat sink, containment integrity, and water inventory in the first control strategy to obtain the third control strategy. In this third control strategy, the priority of primary loop integrity is the highest among the safety functions of the nuclear power plant, and the priority of primary loop integrity is higher than that of the heat sink, the priority of the heat sink is higher than that of the containment integrity, and the priority of the containment integrity is higher than that of the water inventory.

[0093] Step S409: Based on the third control strategy, execute the accident handling procedure.

[0094] In one embodiment, in addition to detecting whether the core of the nuclear power plant has melted, it is also possible to detect whether the main pump of the nuclear power plant is in an operating state, and adjust the priority of the safety function by comprehensively considering the cooling state of the core and the operating state of the main pump.

[0095] Specifically, when it is detected that the core has melted, a severe accident safety function priority control strategy is adopted, that is, the priority of containment integrity is adjusted to the highest; when it is detected that the core has not melted and the main pump is in an operating state, a safety function priority control strategy under the operating state of the main pump is adopted to adjust the priority of the safety function; when it is detected that the core has not melted and the main pump is in a shutdown state, a safety function priority control strategy under the shutdown state of the main pump is adopted to adjust the priority of the safety function. By classifying the cooling state of the core and the operating state of the main pump, and adjusting the priority of the safety function according to different cooling states of the core and different operating states of the main pump, it is possible to provide a basis for the operator to adopt appropriate accident handling procedures in different nuclear power plant accident scenarios, making the accident handling of the nuclear power plant more purposeful and efficient, while reducing the probability of human error and ensuring the safe operation of the nuclear power plant after an accident.

[0096] Please continue to refer to Figure 4 as Figure 4 shown, in another embodiment of the present application, after step S407, the method further includes step S410:

[0097] Step S410: If the subcooling degree is less than the second threshold and greater than the measurement uncertainty of the subcooling degree, and the water level is greater than the third threshold, then based on the first control strategy, execute the accident handling procedure.

[0098] Please refer to Figure 5 In Figure 5 region 2, ε < ΔTsat < SS2 and RPVL > SS3. In this region, the coolant in the primary loop is in an undersaturated state, and the unit state is relatively stable. The first control strategy can continue to be used to execute the accident handling procedure.

[0099] Please continue to refer to Figure 4,like Figure 4 As shown, in another embodiment of the present application, after step S407, the method further includes steps S411 to S413:

[0100] Step S411: if the supercooling degree is less than the measurement uncertainty of the supercooling degree and greater than the negative value of the measurement uncertainty, and the water level is greater than the third threshold, it is determined whether the heat sink of the nuclear power plant is in an available state.

[0101] See also Figure 5 ,exist Figure 5 In area 3, -ε<ΔTsat<ε and RPVL>SS3, in this area, the coolant in the primary circuit is in a saturated state. At this time, it is necessary to check whether the heat sink of the nuclear power plant is in an available state. If the heat sink is in an available state, it means that the heat conduction means on the secondary side of the steam generator is available. Whether the heat sink is in an available state will affect the adjustment of the safety function priority.

[0102] Step S412, if the heat sink is in an unavailable state, the priorities of the first-loop integrity, the heat sink, the containment integrity, the water loading, the subcriticality and the core cooling in the first control strategy are adjusted to obtain a fourth control strategy, wherein in the fourth control strategy, the heat sink has the highest priority in the safety functions of the nuclear power plant, and the priority of the heat sink is higher than the priority of core cooling, the priority of core cooling is higher than the priority of subcriticality, the priority of subcriticality is higher than the priority of the first-loop integrity, the priority of the first-loop integrity is higher than the priority of the containment integrity, and the priority of the containment integrity is higher than the priority of the water loading.

[0103] In one embodiment, if the coolant of a primary circuit is in a saturated state and the heat sink is in an unavailable state, the heat sink is controlled first, and the residual heat extraction means are restored as soon as possible, that is, the heat sink has the highest priority in the safety function of the nuclear power plant. Under this condition, considering that with the generation of steam, a certain amount of cavitation will appear in the core, which is helpful for subcriticality control, therefore, under this condition, the priority of subcriticality is lower than that of core cooling, that is, the priority of core cooling is second only to the heat sink, and the priority of subcriticality is second to that of core cooling. Thereafter, the priority of safety functions is: primary circuit integrity → containment integrity → water loading.

[0104] Step S413, executing the accident handling procedure based on the fourth control strategy.

[0105] Please continue to see Figure 4 ,like Figure 4 As shown, in another embodiment of the present application, after step S411, the method further includes step S414:

[0106] Step S414, if the heat sink is in an available state, then execute the accident handling procedure based on the first control strategy.

[0107] In one embodiment, although the primary coolant is in a saturated state, but the heat sink is in an available state, at this time the stability of the unit is still controllable, so the first control strategy can continue to be used to execute the accident handling procedure.

[0108] Please continue to refer to Figure 4 , such as Figure 4 shown, in another embodiment of the present application, after step S407, the method further includes steps S415 and S416:

[0109] Step S415, if the subcooling degree is less than the negative value of the measurement uncertainty of the subcooling degree or the water level is less than the third threshold, then adjust the priority of core cooling and containment integrity in the first control strategy to obtain the fifth control strategy, wherein, in the fifth control strategy, the priority of core cooling in the safety functions of the nuclear power plant is the highest, and the priority of core cooling is higher than the priority of containment integrity.

[0110] Step S416, execute the accident handling procedure based on the fifth control strategy.

[0111] Please refer to Figure 5 , in Figure 5 region 4 of, ΔTsat < -ε or RPVL < SS3, in this region, ΔTsat < -ε means that superheated steam appears (i.e., the core has been partially uncovered), and RPVL < SS3 means that the core is about to be uncovered or has already started to be uncovered. First, core cooling control needs to be carried out to avoid core melting, and then control is carried out for the containment to ensure the integrity of the third safety barrier, that is, the priority of core cooling in the safety functions of the nuclear power plant is the highest, and the priority of core cooling is higher than the priority of containment integrity.

[0112] In this region, there may be a large void coefficient in the core. Considering the moderator effect brought by the voids, subcriticality control is not required under this condition. At the same time, considering that a large amount of the primary coolant is discharged through the break, the heat removal of the core is already dominated by the break, and the integrity of the primary pressure boundary has been lost. Therefore, control of safety functions such as the heat sink, primary integrity, and water inventory is not required.

[0113] Through the above steps S101 to S103, steps S201 to S206 and steps S407 to S416, the cooling state of the core is determined by detecting whether the core of the nuclear power plant has melted. When the core has melted, it is determined that a serious accident has occurred in the nuclear power plant, and the priority of the containment integrity is adjusted to the highest, so as to give top priority to maintaining the integrity of the containment as a safety barrier after the accident; and when the core has not melted, the operating state of the main pump is detected. When it is detected that the main pump is in an operating state, the priority of the safety function is adjusted by the safety function priority control strategy in the main pump operating state; when it is detected that the main pump is in a shutdown state, the priority of the safety function is adjusted by the safety function priority control strategy in the main pump shutdown state.

[0114] Specifically, by dividing the cooling state of the core and the operating state of the main pump, and adjusting the priority of the safety function according to the different cooling states of the core and the different operating states of the main pump, it can provide a basis for operators to adopt appropriate accident handling procedures in different nuclear power plant accident scenarios, making the accident handling of the nuclear power plant more purposeful and efficient, while reducing the probability of human errors and ensuring the safe operation of the nuclear power plant after the accident.

[0115] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0116] Corresponding to the accident handling method of the nuclear power plant described in the above embodiment, Figure 6 A schematic diagram of an application scenario according to an embodiment of the present application is shown. In this application scenario, a main steam line break (SLB) occurs in a nuclear power plant. The accident handling method of the nuclear power plant provided in the embodiment of the present application is described below in conjunction with the accident handling process in the application scenario.

[0117] An SLB accident will cause severe overcooling of the primary circuit. Although the nuclear power plant has automatically shut down at this time, the positive reactivity introduced into the core causes the core to return to criticality and significantly generate nuclear power. The cooling contraction of the coolant in the primary circuit also causes the water capacity to be degraded. If the safety injection system or the emergency boronization system is not shut down in time, the re-pressurization of the primary circuit will cause stress risks in the pressure vessel.

[0118] In this application scenario, if the accident handling procedure is executed according to the priority of the safety function that is consistent in any accident scenario, when ΔTsat is greater than SS2, if the operator performs the accident handling without adjusting the safety level, it will waste the precious response time under the accident condition, bringing difficulties and obstacles to the accident handling of the nuclear power plant.

[0119] See also Figure 6 In one embodiment, the accident handling method of the nuclear power plant provided by the present application can detect the supercooling ΔTsat of the outlet coolant of the core, and determine SS2 as 140°C. If ΔTsat is greater than 140°C, the accident handling target at this time is to reduce the supercooling of the primary circuit, and the accident handling is performed according to the third control strategy. After a period of accident handling according to the third control strategy, ΔTsat decreases. If ε<ΔTsat<140°C, the accident handling target at this time is to stabilize nuclear power control. Since the coolant of the primary circuit is in an undersaturated state, the unit state is relatively stable, and the first control strategy can continue to be used to execute the accident handling procedure.

[0120] In other embodiments, if ε<ΔTsat<140°C is detected after the SLB accident occurs, the accident handling target at this time is to retreat to the cold shutdown. Since the coolant in the primary circuit is in an undersaturated state, the unit state is relatively stable, and the first control strategy can still be used to execute the accident handling procedure. The priority of the safety function is adjusted according to different nuclear power plant accident scenarios to provide a basis for the operator to adopt appropriate accident handling procedures, making the accident handling of the nuclear power plant more purposeful and efficient, while reducing the probability of human error and ensuring the safe operation of the nuclear power plant after the accident.

[0121] Corresponding to the accident handling method of the nuclear power plant described in the above embodiment, Figure 7 A schematic structural diagram of an accident handling device of a nuclear power plant according to an embodiment of the present application is shown. For ease of explanation, only the parts related to the embodiment of the present application are shown.

[0122] See also Figure 7 The accident handling device 7 of the nuclear power plant includes: a detection module 70, which is used to detect whether the core of the nuclear power plant has melted; an adjustment module 71, which is used to adjust the priority of the containment integrity in the preset first control strategy when the core has melted, and obtain a second control strategy, wherein in the second control strategy, the containment integrity has the highest priority in the safety functions of the nuclear power plant, so as to indicate that the containment integrity is maintained first after an accident occurs in the nuclear power plant; an execution module 72, which is used to execute the accident handling procedure based on the second control strategy.

[0123] In some embodiments, the safety functions of the nuclear power plant also include primary loop integrity, heat sink and water loading. The detection module 70 is also used to determine whether the main pump of the nuclear power plant is in operation when the core has not melted; the detection module 70 is also used to detect the subcooling of the outlet coolant of the core when the main pump is in operation; the adjustment module 71 is also used to adjust the priority of primary loop integrity, heat sink, containment integrity and water loading in the first control strategy when the subcooling is greater than a preset first threshold value, to obtain a third control strategy, wherein in the third control strategy, primary loop integrity has the highest priority among the safety functions of the nuclear power plant, and the priority of primary loop integrity is higher than that of heat sink, the priority of heat sink is higher than that of containment integrity, and the priority of containment integrity is higher than that of water loading; the execution module 72 is also used to execute the accident handling procedure based on the third control strategy.

[0124] In some embodiments, the execution module 72 is further configured to execute an accident handling procedure based on the first control strategy when the degree of supercooling is less than a first threshold and greater than a measurement uncertainty of the degree of supercooling.

[0125] In some embodiments, the execution module 72 is further configured to shut down the main pump when the subcooling degree is less than the measurement uncertainty of the subcooling degree.

[0126] In some embodiments, the detection module 70 is also used to detect the subcooling of the outlet coolant of the core and the water level of the pressure vessel when the main pump is in a shutdown state; the adjustment module 71 is also used to adjust the priority of the first loop integrity, heat sink, containment integrity and water charge in the first control strategy to obtain the third control strategy when the subcooling is greater than a preset second threshold and the water level is greater than a preset third threshold, and the execution module 72 is also used to execute the accident handling procedure based on the third control strategy.

[0127] In some embodiments, the execution module 72 is further configured to execute an accident handling procedure based on the first control strategy when the degree of supercooling is less than a second threshold value and greater than a measurement uncertainty of the degree of supercooling, and the water level is greater than a third threshold value.

[0128] In some embodiments, the safety functions of the nuclear power plant also include subcriticality and core cooling. The detection module 70 is also used to determine whether the heat sink of the nuclear power plant is in an available state when the supercooling is less than the measurement uncertainty of the supercooling and greater than the negative value of the measurement uncertainty, and the water level is greater than a third threshold value; the adjustment module 71 is also used to adjust the priority of the first-loop integrity, the heat sink, the containment integrity, the water loading, the subcriticality and the core cooling in the first control strategy when the heat sink is in an unavailable state, to obtain a fourth control strategy, wherein in the fourth control strategy, the heat sink has the highest priority in the safety functions of the nuclear power plant, and the priority of the heat sink is higher than the priority of core cooling, the priority of core cooling is higher than the priority of subcriticality, the priority of subcriticality is higher than the priority of the first-loop integrity, the priority of the first-loop integrity is higher than the priority of the containment integrity, and the priority of the containment integrity is higher than the priority of the water loading; the execution module 72 is also used to execute the accident handling procedure based on the fourth control strategy.

[0129] In some embodiments, the execution module 72 is further configured to execute an accident handling procedure based on the first control strategy when the heat sink is in an available state.

[0130] In some embodiments, the safety functions of the nuclear power plant also include core cooling. After detecting the subcooling of the core's outlet coolant and the water level of the pressure vessel, the adjustment module 71 is also used to adjust the priority of core cooling and containment integrity in the first control strategy when the subcooling is less than the negative value of the measurement uncertainty of the subcooling or the water level is less than a third threshold, to obtain a fifth control strategy, wherein in the fifth control strategy, core cooling has the highest priority in the safety functions of the nuclear power plant, and the priority of core cooling is higher than the priority of containment integrity; the execution module 72 is also used to execute the accident handling procedure based on the fifth control strategy.

[0131] It should be noted that the information interaction, execution process, etc. between the above-mentioned devices / units are based on the same concept as the method embodiment of the present application. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0132] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0133] Figure 8 is a schematic diagram of the structure of a terminal device according to an embodiment of the present application. Figure 8 As shown, the terminal device 8 includes: at least one processor 80 ( Figure 8 Only one is shown in the figure) a processor, a memory 81, and a computer program 82 stored in the memory 81 and executable on at least one processor 80, and when the processor 80 executes the computer program 82, the steps in any of the above-mentioned accident handling method embodiments of the nuclear power plant are implemented.

[0134] The terminal device 8 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The terminal device 8 may include but is not limited to a processor 80 and a memory 81. It is understood by those skilled in the art that Figure 8 It is only an example of the terminal device 8 and does not constitute a limitation on the terminal device 8. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, it may also include input and output devices, network access devices, etc.

[0135] The processor 80 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0136] In some embodiments, the memory 81 may be an internal storage unit of the terminal device 8, such as a hard disk or memory of the terminal device 8. In other embodiments, the memory 81 may also be an external storage device of the terminal device 8, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the terminal device 8. In other embodiments, the memory 81 may also include both an internal storage unit and an external storage device of the terminal device 8. The memory 81 is used to store an operating system, an application program, a boot loader (BootLoader), data, and other programs, such as program codes of a computer program 82. The memory 81 may also be used to temporarily store data that has been output or is to be output.

[0137] The embodiment of the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it can implement the steps in the above-mentioned accident handling method embodiments of each nuclear power plant.

[0138] An embodiment of the present application provides a computer program product. When the computer program product runs on a mobile terminal, the mobile terminal can implement the steps in the above-mentioned accident handling method embodiments of each nuclear power plant when executing the computer program product.

[0139] The present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of each of the above-mentioned method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may at least include: any entity or device that can carry the computer program code to the camera device / terminal device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal and software distribution medium. For example, a USB flash drive, a mobile hard disk, a disk or an optical disk.

[0140] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0141] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0142] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0143] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0144] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for handling an accident in a nuclear power plant, wherein the safety function of the nuclear power plant includes containment integrity, characterized in that: The method comprises: Detecting whether a core of the nuclear power plant has melted; If the core melts, the priority of the containment integrity in the preset first control strategy is adjusted to obtain a second control strategy, wherein in the second control strategy, the containment integrity has the highest priority among the safety functions of the nuclear power plant, so as to indicate that the containment integrity is maintained first after an accident occurs in the nuclear power plant; Based on the second control strategy, an accident handling procedure is executed.

2. The method according to claim 1, characterized in that The safety functions of the nuclear power plant also include primary circuit integrity, heat sink and water charge, and after detecting whether the core of the nuclear power plant has melted, it also includes: If the core has not melted, determining whether the main pump of the nuclear power plant is in operation; If the main pump is in operation, detecting the subcooling degree of the outlet coolant of the core; If the degree of undercooling is greater than a preset first threshold, the priorities of the primary loop integrity, the heat sink, the containment integrity and the water loading in the first control strategy are adjusted to obtain a third control strategy, wherein, in the third control strategy, the primary loop integrity has the highest priority in the safety function of the nuclear power plant, and the priority of the primary loop integrity is higher than the priority of the heat sink, the priority of the heat sink is higher than the priority of the containment integrity, and the priority of the containment integrity is higher than the priority of the water loading; Based on the third control strategy, an accident handling procedure is executed.

3. The method according to claim 2, characterized in that After detecting the subcooling degree of the outlet coolant of the core, the method further comprises: If the degree of subcooling is less than the first threshold value and greater than the measurement uncertainty of the degree of subcooling, an accident handling procedure is executed based on the first control strategy.

4. The method according to claim 2 or 3, characterized in that: After detecting the subcooling degree of the outlet coolant of the core, the method further comprises: If the subcooling degree is less than the measurement uncertainty of the subcooling degree, the main pump is shut down.

5. The method according to claim 2, characterized in that: After determining whether the main pump of the nuclear power plant is in operation, the method further includes: If the main pump is in a shutdown state, detecting the subcooling degree of the outlet coolant of the core and the water level of the pressure vessel; If the degree of subcooling is greater than a preset second threshold and the water level is greater than a preset third threshold, adjusting the priorities of the primary loop integrity, the heat sink, the containment integrity and the water charge in the first control strategy to obtain a third control strategy; Based on the third control strategy, an accident handling procedure is executed.

6. The method according to claim 5, characterized in that After detecting the subcooling degree of the outlet coolant of the core and the water level of the pressure vessel, the method further includes: If the degree of subcooling is less than the second threshold and greater than the measurement uncertainty of the degree of subcooling, and the water level is greater than the third threshold, an accident handling procedure is executed based on the first control strategy.

7. The method according to claim 5 or 6, characterized in that: The safety functions of the nuclear power plant also include subcriticality and core cooling. After detecting the subcooling of the outlet coolant of the core and the water level of the pressure vessel, the following steps are also included: If the subcooling degree is less than the measurement uncertainty of the subcooling degree and greater than the negative value of the measurement uncertainty, and the water level is greater than the third threshold, determining whether the heat sink of the nuclear power plant is in an available state; If the heat sink is in an unavailable state, the priorities of the primary loop integrity, the heat sink, the containment integrity, the water loading, the subcriticality and the core cooling in the first control strategy are adjusted to obtain a fourth control strategy, wherein, in the fourth control strategy, the heat sink has the highest priority in the safety functions of the nuclear power plant, and the priority of the heat sink is higher than the priority of the core cooling, the priority of the core cooling is higher than the priority of the subcriticality, the priority of the subcriticality is higher than the priority of the primary loop integrity, the priority of the primary loop integrity is higher than the priority of the containment integrity, and the priority of the containment integrity is higher than the priority of the water loading; Based on the fourth control strategy, an accident handling procedure is executed.

8. The method according to claim 7, characterized in that After determining whether the heat sink of the nuclear power plant is in an available state, the method further includes: If the heat sink is in an available state, an accident handling procedure is executed based on the first control strategy.

9. The method according to claim 5 or 6, characterized in that: The safety function of the nuclear power plant also includes core cooling, and after detecting the subcooling degree of the outlet coolant of the core and the water level of the pressure vessel, it also includes: If the undercooling degree is less than the negative value of the measurement uncertainty of the undercooling degree or the water level is less than the third threshold value, the priorities of the core cooling and the containment integrity in the first control strategy are adjusted to obtain a fifth control strategy, wherein in the fifth control strategy, the core cooling has the highest priority in the safety function of the nuclear power plant, and the priority of the core cooling is higher than the priority of the containment integrity; Based on the fifth control strategy, an accident handling procedure is executed.

10. An accident handling device for a nuclear power plant, wherein the safety function of the nuclear power plant includes containment integrity, characterized in that: include: A detection module, used to detect whether the core of the nuclear power plant has melted; an adjustment module, configured to adjust the priority of the containment integrity in a preset first control strategy when the core melts, to obtain a second control strategy, wherein in the second control strategy, the containment integrity has the highest priority among the safety functions of the nuclear power plant, so as to indicate that the containment integrity is first maintained after an accident occurs in the nuclear power plant; An execution module is used to execute an accident handling procedure based on the second control strategy.

11. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 9 is implemented.

12. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 9 is implemented.

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