Analysis method and device for start-stop operation strategy of nuclear power plant

Abstract

The invention discloses a method and a device for analyzing a start-stop operation strategy of a nuclear power plant. The method comprises the following steps: identifying an operation mode in a start-stop process of the nuclear power plant; determining the conversion relation of each operation mode in the start-stop process of the nuclear power plant; determining the operation state of the system function in each operation mode; performing demand analysis on the system function based on the conversion relation and the operation state of the system function; and determining a start-stop sequence control logic function group based on the demand analysis result, and forming a start-stop operation strategy of the nuclear power plant. Compared with the start-stop strategy design according to the step sequence, the method can better guarantee the integrity and normalization of the start-stop strategy, the operation parameters are calculated through the logic equation, the operation mode of the nuclear power plant can be automatically determined more quickly and more accurately, it is guaranteed that the start-stop operation strategy of the nuclear power plant better meets the actual operation requirement, and the operation efficiency is improved. Therefore, the operation efficiency and safety of the nuclear power plant are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power plant automation control, and in particular to a method and device for analyzing the start-stop operation strategy of a nuclear power plant. Background Art

[0002] Nuclear power units generally have the characteristics of a large number of equipment, high operating parameters, and complex control system structure. Especially during the startup and shutdown process of the unit, there are a lot of complex manual operations. Operators usually need to complete the startup of nuclear power plant equipment, the lifting of control rods, the criticality of the reactor, the power increase, the reactor coordination and other operations in the main control room. During the manual operation of the operator, human error may occur. With the continuous development of instrumentation and control technology, the automatic start and stop system (APS) of the unit has received more and more attention as an effective method to improve the level of automation. APS is a system that realizes the automation of the unit startup and shutdown process. Its advantage is that it can improve the correctness and standardization of the unit startup and shutdown, reduce the workload of operators, shorten the startup and shutdown time of the unit, and improve the overall level of automation of the unit. At present, APS is mainly used in thermal power units, while nuclear power units are not widely used due to the complexity and safety of their operation. Therefore, it is very important to study the automatic start and stop operation strategy of nuclear power plants. For nuclear power plants, if the automatic start-stop strategy is analyzed according to the conventional start-stop operation sequence, and the functional groups of the automatic start-stop system are divided according to the start-stop sequence, it is often impossible to complete a comprehensive and complete analysis due to the complex interactions between nuclear power unit systems, the numerous steps, and the many operating requirements and restrictions. It is difficult to fully and completely determine all the functional groups.

[0003] The existing patent CN114446502A discloses a design method for an automatic start-stop and intelligent monitoring system for a nuclear power plant. The scheme proposes how to specifically carry out the APS design and considers the relevant contents of intelligent monitoring. Specifically, the following steps are included: task analysis of the start-stop operation process of the nuclear power plant; determination of the design scope of the ANPS system of the nuclear power plant; functional group design of the ANPS control system of the nuclear power plant; sequential control function flow design of the ANPS of the nuclear power plant; closed-loop adjustment function design of the main process parameters of the ANPS system of the nuclear power plant; intelligent monitoring module design of the operation status of the unit start-stop process of the ANPS system of the nuclear power plant; integrated design of the ANPS system of the nuclear power plant; human-machine interface function design of the ANPS system of the nuclear power plant; verification and confirmation of the design scheme of the ANPS system of the nuclear power plant.

[0004] The existing patent CN116705367A discloses a method for setting interruption points of an automatic start and stop system of a nuclear power plant, which is used for setting interruption points of an automatic start and stop system of a nuclear power plant. The method comprises: S1, obtaining the start and stop operation of the unit of the automatic start and stop system of the nuclear power plant and the initial parameters of the nuclear power plant; S2, judging whether the start and stop operation of the unit meets the interruption point setting principle according to the initial parameters of the nuclear power plant; S3, if the start and stop operation of the unit meets the interruption point setting principle, setting interruption points before and after the start and stop operation of the unit to obtain a preliminary list of interruption points; S4, based on the preliminary list of interruption points, setting the start and stop operations of the unit between adjacent interruption points as a breakpoint sequence to obtain a breakpoint sequence list of the automatic start and stop system of the nuclear power plant.

[0005] In summary, the above two existing patents have not solved the problems faced by the prior art in determining the automatic start and stop strategy of nuclear power units according to step analysis, such as unclear hierarchy, omitted steps, incomplete functional group analysis and confusing operating restrictions. Summary of the invention

[0006] Based on the above technical problems, the present invention proposes a method and device for analyzing the start-stop operation strategy of a nuclear power plant, which solves the problems faced by the prior art in determining the automatic start-stop strategy of nuclear power units by step analysis, such as unclear hierarchy, missing steps, incomplete function group analysis and confusion of operation restriction conditions.

[0007] A method for analyzing the start-up and shutdown operation strategy of a nuclear power plant, comprising:

[0008] Identify the operating modes during the startup and shutdown of nuclear power plants;

[0009] Determine the conversion relationship between various operating modes during the start-up and shutdown process of the nuclear power plant;

[0010] Determine the operating status of system functions in each operating mode;

[0011] Based on the conversion relationship and the operating status of the system functions, the system functions are required to be analyzed;

[0012] Based on the demand analysis results, the start-stop sequence control logic function group is determined, and the start-stop operation strategy of the nuclear power plant is formed.

[0013] Furthermore, it also includes:

[0014] Use the simulation platform to determine whether the start-stop operation strategy is reasonable;

[0015] If the start-stop operation strategy is unreasonable, the operating status of the system functions in each operating mode will be re-determined.

[0016] Furthermore, the operation mode of the nuclear power plant during startup and shutdown is identified, including:

[0017] Set corresponding logic equations for each operating mode;

[0018] Obtaining operating parameters during the start-up and shutdown process of the nuclear power plant, the operating parameters including one or more of reactivity, thermal power, and average core temperature;

[0019] The operating parameters are input into the logistic equations to identify the operating mode of the nuclear power plant.

[0020] Furthermore, the operation modes include power operation, hot standby, hot shutdown, cold shutdown and maintenance shutdown.

[0021] The logic equation corresponding to the power operation is, M1 = thermal power > 30%;

[0022] The logic equation corresponding to hot standby is: Where, “·” represents the AND operator, T1 is the minimum critical temperature, P6 represents the intermediate range neutron flux > 10-5% Pn, is the non-value of the thermal shutdown signal value, is the non-value of the cold shutdown signal value, It is the non-value of the maintenance trip signal value;

[0023] The logic equation corresponding to the thermal shutdown is: Among them, T2 is the lowest average temperature that provides sufficient residual reactivity in the core for a rod ejection accident. For the intermediate range neutron flux ≤10-5%Pn;

[0024] The logic equation corresponding to the cold shutdown is:

[0025] The logic equation corresponding to the maintenance outage is: T3 is the upper limit temperature at which material replacement and maintenance operations can be performed.

[0026] Furthermore, the conversion relationship between each operation mode during the startup process of the nuclear power plant is determined, including:

[0027] Starting a nuclear power plant unit from a cold shutdown state to a power operation state will experience a transition from cold shutdown to hot standby to power operation mode;

[0028] Starting a nuclear power plant unit from a hot shutdown state to a power operation state will experience a transition from hot shutdown to hot standby to power operation mode.

[0029] Furthermore, the conversion relationship between each operation mode during the shutdown process of the nuclear power plant is determined, including:

[0030] Shutting down a nuclear power plant unit from a power operation state to a hot shutdown state will involve a transition from a power operation mode directly to a hot shutdown mode;

[0031] Shutting down a nuclear power plant unit from a power operation state to a cold shutdown state will involve a transition from a power operation mode directly to a cold shutdown mode.

[0032] Furthermore, before determining the operating status of the system functions under the various operating modes, it includes: determining the system and the corresponding system functions under the various operating modes according to the start-stop operation sequence, the system including one or more of a heat trap system, a main loop system, an auxiliary system, and a reactor control system, the system function corresponding to the heat trap system is a heat trap function, the system functions corresponding to the main loop system include a helium filling and exhaust function and a helium turbine function, the system functions corresponding to the auxiliary system include a helium sampling and monitoring function and a purification function, and the system function corresponding to the reactor control system is a control rod adjustment function.

[0033] Furthermore, the operating status of the system functions in each operating mode is determined, including:

[0034] In the cold shutdown operation mode, the heat sink function and the helium turbine function are in shutdown state, and the control rod adjustment function is in the cold shutdown rod position;

[0035] In the hot shutdown operation mode, the heat sink function and the helium turbine function are in shutdown state, and the control rod adjustment function is in the hot shutdown rod position;

[0036] The hot standby operation modes include critical state, low power state, self-sustaining state and auxiliary power state. In the critical state, the heat sink function is in the start-up state, the helium turbine function is in the state of starting the turbine to the preset target speed, and the control rod adjustment function is in the critical rod position of the critical rod lifting mode.

[0037] In the low power state and the auxiliary power state, the heat sink function is in the automatic control state, the helium turbine function is in the preset target speed state, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve.

[0038] In the self-sustaining state, the heat sink function is in automatic control, the helium turbine function is in self-sustaining mode, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve.

[0039] In the power operation mode, the heat sink function is in automatic control, the helium turbine function is in load following mode, and the control rod adjustment function is in load following mode.

[0040] Furthermore, based on the demand analysis result, a sequential control logic function group in the critical state process from cold shutdown to hot standby mode is determined, including:

[0041] The first functional group is used to start the heat trap system, the second functional group is used to start the filling and exhaust system, the third functional group is used to start the helium turbine to a preset target speed state, the fourth functional group is used for helium sampling monitoring and purification, and the fifth functional group is used to raise the rod to a critical state.

[0042] The first functional group includes a first functional subgroup for starting a heat sink low-flow cycle, a second functional subgroup for operating a heat sink compressor circuit, a third functional subgroup for operating a heat sink vacuum pump circuit, a fourth functional subgroup for operating a heat sink intercooler and precooler circuit, and a fifth functional subgroup for operating a heat sink generator circuit.

[0043] Furthermore, after determining the start-stop sequence control logic function group, the method further includes: analyzing the logical relationship between each function group.

[0044] Furthermore, the first function group, the second function group, the third function group, the fourth function group and the fifth function group are in a logical relationship of sequential execution.

[0045] In order to achieve the same purpose as the above method, the present invention also proposes an analysis device for the start-up and shutdown operation strategies of a nuclear power plant.

[0046] An analysis device for the start-up and shutdown operation strategy of a nuclear power plant, comprising:

[0047] Identification module, used to identify the operation mode during the start-up and shutdown process of the nuclear power plant;

[0048] The first determination module is used to determine the conversion relationship between various operation modes during the start-up and shutdown process of the nuclear power plant;

[0049] The second determination module is used to determine the operating status of the system function in each operating mode;

[0050] The demand analysis module is used to analyze the demand of system functions based on the conversion relationship and the operating status of system functions;

[0051] The generation module is used to determine the start-stop sequence control logic function group based on the demand analysis results and form the start-stop operation strategy of the nuclear power plant.

[0052] Furthermore, it also includes:

[0053] Use the simulation platform to determine whether the start-stop operation strategy is reasonable;

[0054] If the start-stop operation strategy is unreasonable, the operating status of the system functions in each operating mode will be re-determined.

[0055] Furthermore, the identification module is used to:

[0056] Set corresponding logic equations for each operating mode;

[0057] Obtaining operating parameters during the start-up and shutdown process of the nuclear power plant, the operating parameters including one or more of reactivity, thermal power, and average core temperature;

[0058] The operating parameters are input into the logistic equations to identify the operating mode of the nuclear power plant.

[0059] Furthermore, the operation modes include power operation, hot standby, hot shutdown, cold shutdown and maintenance shutdown.

[0060] The logic equation corresponding to the power operation is, M1 = thermal power > 30%;

[0061] The logic equation corresponding to hot standby is: Where, “·” represents the AND operator, T1 is the minimum critical temperature, P6 represents the intermediate range neutron flux > 10-5% Pn, is the non-value of the thermal shutdown signal value, is the non-value of the cold shutdown signal value, It is the non-value of the maintenance trip signal value;

[0062] The logic equation corresponding to the thermal shutdown is: Among them, T2 is the lowest average temperature that provides sufficient residual reactivity in the core for a rod ejection accident. Indicates that the intermediate range neutron flux is ≤10-5%Pn;

[0063] The logic equation corresponding to the cold shutdown is:

[0064] The logic equation corresponding to the maintenance outage is: T3 is the upper limit temperature at which material replacement and maintenance operations can be performed.

[0065] Furthermore, the first determining module is used to:

[0066] Starting a nuclear power plant unit from a cold shutdown state to a power operation state will experience a transition from cold shutdown to hot standby to power operation mode;

[0067] Starting a nuclear power plant unit from a hot shutdown state to a power operation state will experience a transition from hot shutdown to hot standby to power operation mode.

[0068] Furthermore, the first determining module is used to:

[0069] Shutting down a nuclear power plant unit from a power operation state to a hot shutdown state will involve a transition from a power operation mode directly to a hot shutdown mode;

[0070] Shutting down a nuclear power plant unit from a power operation state to a cold shutdown state will involve a transition from a power operation mode directly to a cold shutdown mode.

[0071] Furthermore, before determining the operating status of the system functions under the various operating modes, it includes: determining the systems and corresponding functions under the various operating modes according to the start-stop operation sequence, the systems including one or more of a heat trap system, a main loop system, an auxiliary system, and a reactor control system, the system function corresponding to the heat trap system is a heat trap function, the system functions corresponding to the main loop system include a helium filling and exhaust function and a helium turbine function, the system functions corresponding to the auxiliary system include a helium sampling and monitoring function and a purification function, and the system function corresponding to the reactor control system is a control rod adjustment function.

[0072] Furthermore, the second determining module is used to:

[0073] In the cold shutdown operation mode, the heat sink function and the helium turbine function are in shutdown state, and the control rod adjustment function is in the cold shutdown rod position;

[0074] In the hot shutdown operation mode, the heat sink function and the helium turbine function are in shutdown state, and the control rod adjustment function is in the hot shutdown rod position;

[0075] The hot standby operation modes include critical state, low power state, self-sustaining state and auxiliary power state. In the critical state, the heat sink function is in the start-up state, the helium turbine function is in the state of starting the turbine to the preset target speed, and the control rod adjustment function is in the critical rod position of the critical rod lifting mode.

[0076] In the low power state and the auxiliary power state, the heat sink function is in the automatic control state, the helium turbine function is in the preset target speed state, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve.

[0077] In the self-sustaining state, the heat sink function is in automatic control, the helium turbine function is in self-sustaining mode, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve.

[0078] In the power operation mode, the heat sink function is in automatic control, the helium turbine function is in load following mode, and the control rod adjustment function is in load following mode.

[0079] Furthermore, based on the demand analysis result, a sequential control logic function group in the critical state process from cold shutdown to hot standby mode is determined, including:

[0080] The first functional group is used to start the heat trap system, the second functional group is used to start the filling and exhaust system, the third functional group is used to start the helium turbine to a preset target speed state, the fourth functional group is used for helium sampling monitoring and purification, and the fifth functional group is used to raise the rod to a critical state.

[0081] The first functional group includes a first functional subgroup for starting a heat sink low-flow cycle, a second functional subgroup for operating a heat sink compressor circuit, a third functional subgroup for operating a heat sink vacuum pump circuit, a fourth functional subgroup for operating a heat sink intercooler and precooler circuit, and a fifth functional subgroup for operating a heat sink generator circuit.

[0082] Furthermore, after determining the start-stop sequence control logic function group, the method further includes: analyzing the logical relationship between each function group.

[0083] Furthermore, the first function group, the second function group, the third function group, the fourth function group and the fifth function group are in a logical relationship of sequential execution.

[0084] Based on the above technical solution, the present invention has at least the following beneficial effects:

[0085] 1. The present invention determines the conversion relationship between various operating modes during the start-up and shutdown process of the nuclear power plant, and the operating status of the system functions under each operating mode. Based on the conversion relationship and the operating status of the system functions, the system functions are analyzed for demand and the start-up and shutdown sequential control logic function group is determined, and finally the start-up and shutdown operation strategy of the nuclear power plant is formed. Compared with designing the start-up and shutdown strategy according to the step sequence, this method can better ensure the integrity and standardization of the start-up and shutdown strategy.

[0086] 2. The present invention sets corresponding logic equations for the operating modes of nuclear power plants, calculates operating parameters using the logic equations, and automatically identifies and calculates the operating modes of nuclear power plants. Compared with designing start-stop strategies in sequence, the present invention can determine the operating modes of nuclear power plants more quickly and accurately, laying an important foundation for subsequent analysis of the conversion relationship of operating modes and analysis of the operating status of system functions, and can ensure that the start-stop operation strategies of nuclear power plants are more in line with actual operating requirements, thereby improving the operating efficiency and safety of nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0088] Figure 1 A flow chart of an analysis method for a start-up and shutdown operation strategy of a nuclear power plant according to an embodiment of the present invention;

[0089] Figure 2 A flow chart of an analysis method for a start-up and shutdown operation strategy of a nuclear power plant according to another embodiment of the present invention;

[0090] Figure 3 A schematic diagram of an analysis device for start-up and shutdown operation strategies of a nuclear power plant according to an embodiment of the present invention. DETAILED DESCRIPTION

[0091] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0092] The present invention is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed by the present invention.

[0093] Example

[0094] In order to solve the problems faced by the prior art in determining the automatic start and stop strategy of nuclear power units by step analysis, such as unclear hierarchy, missing steps, incomplete function group analysis and confusion of operation restriction conditions, the present invention proposes an analysis method and device for the start and stop operation strategy of a nuclear power plant.

[0095] To achieve the above object, the present invention proposes a method for analyzing the start-up and shutdown operation strategies of a nuclear power plant.

[0096] like Figure 1 FIG. 4 is a flow chart of a method for analyzing a start-up and shutdown operation strategy of a nuclear power plant according to an embodiment of the present invention. The method comprises the following steps:

[0097] S1, identify the operation mode during the startup and shutdown of the nuclear power plant.

[0098] There are multiple operating modes in the process of nuclear power plant startup and shutdown. Different operating modes have different requirements for the control functions and operating limits of power plant startup and shutdown. The startup and shutdown strategy of nuclear power plants depends on the full analysis of the mode, such as the most common power operation, hot standby, hot shutdown, cold shutdown, maintenance shutdown and other mode states. Different modes have different requirements for the state of the system and parameters. Only when they meet the requirements can the next mode conversion be carried out. Therefore, mode analysis and identification is the basis for the analysis of startup and shutdown strategies. The mode must cover all important conversion processes in the startup and shutdown process and all modes in the technical requirements for nuclear power plant operation. Furthermore, the principles that the unit mode of a nuclear power plant should have include: uniqueness, the nuclear power unit can only be in a unique operating mode state at any time; full coverage, all modes combined should be able to cover the entire range of modes contained in the unit during startup and shutdown and operation; consistency, the consistency of relevant process parameters should be met between the set modes.

[0099] Considering the inherent characteristics of high safety, simple structure and small number of systems of the air-cooled micro-reactor, the present invention uses a certain air-cooled micro-reactor as an example to explain the method more clearly and explicitly.

[0100] Furthermore, the operation mode of the nuclear power plant during startup and shutdown is identified, including:

[0101] S101, setting a corresponding logic equation for each operation mode.

[0102] The gas-cooled micro reactor in this embodiment includes the following five operating modes: power operation, hot standby, hot shutdown, cold shutdown and maintenance shutdown. The operating parameter states corresponding to each operating mode / operating condition in this embodiment are shown in Table 1. Taking the power operating condition as an example, the reactivity under this condition is greater than or equal to 0.99, and the thermal power is greater than 30% Pn.

[0103] Table 1 Operating parameter status corresponding to the gas-cooled micro-reactor operating mode / condition

[0104] Serial number Operating condition name Responsiveness Thermal power Average core temperature 1 Power operating conditions ≥0.99 >30%Pn not applicable 2 Hot standby condition ≥0.99 ≤30%Pn ≥T1 3 Hot shutdown condition <0.99 not applicable ≥T2 4 Cold shutdown condition <0.99 not applicable <T2 5 Maintenance shutdown condition not applicable not applicable ≤T3

[0105] Furthermore, the nuclear power unit automatically identifies the current operating mode of the nuclear power plant by setting a logic equation for each operating mode. The nuclear power plant operating condition logic equation refers to a logical calculation equation that combines specific operating parameters through signal logic such as "and", "or", and "not" to characterize the various operating states of the nuclear power plant. The output value of this type of equation is a logical value of "0" or "1", which can be used in the computer information and control system of the nuclear power plant to realize the function of automatically calculating the current operating condition. Specifically, the logic equations corresponding to the five operating modes of the gas-cooled micro-reactor in this embodiment are as follows:

[0106] (1) The logic equation corresponding to power operation is: M1 = thermal power > 30%. When thermal power > 30%, M1 = 1, indicating that the current nuclear power plant is in power operation mode.

[0107] (2) The logic equation corresponding to hot standby is:

[0108]

[0109] Where, “·” represents the AND operator, T1 is the minimum critical temperature, P6 represents the intermediate range neutron flux > 10-5% Pn, is the non-value of the thermal shutdown signal value, is the non-value of the cold shutdown signal value, A non-value representing the maintenance trip signal value.

[0110] (3) The logic equation corresponding to the thermal shutdown is: Among them, T2 is the lowest average temperature that provides sufficient residual reactivity in the core for a rod ejection accident. The intermediate range neutron flux is ≤10-5%Pn.

[0111] (4) The logic equation corresponding to the cold shutdown is:

[0112] (5) The logic equation corresponding to the maintenance shutdown is: T3 is the upper limit temperature at which material replacement and maintenance operations can be performed.

[0113] S102, obtaining operating parameters during the start-up and shutdown process of the nuclear power plant.

[0114] The operating parameters include one or more of reactivity, thermal power, and average core temperature. The operating parameters obtained in this embodiment include reactivity, thermal power, and average core temperature.

[0115] S103, inputting the operating parameters into the logic equation to identify the operating mode of the nuclear power plant.

[0116] After obtaining the above parameters, they are input into the logic equations, and the current operation mode of the nuclear power plant is identified according to the calculation results of each logic equation. According to the uniqueness principle of the nuclear power plant unit mode, the nuclear power unit can only be in a unique operation mode state at any time, that is, at the same time, only one result calculated by the above logic equation is 1.

[0117] S2, determining the conversion relationship between various operating modes during the start-up and shutdown process of the nuclear power plant.

[0118] The start-up and shutdown process of nuclear power plant units corresponds to different automatic start-up and shutdown strategies depending on the initial or final state of the start-up and shutdown. Therefore, analyzing and determining the conversion relationship between different modes is a prerequisite for analyzing the automatic start-up and shutdown strategy. Since maintenance shutdown can be considered as a special mode state of cold shutdown, the concept of cold shutdown can be directly used when analyzing the mode conversion of the start-up and shutdown process.

[0119] The startup process refers to the process of starting the unit from the shutdown state and increasing the power to the power operation state after criticality. Specifically, the conversion relationship between each operation mode during the startup process of a nuclear power plant is determined, including the following two situations:

[0120] Starting a nuclear power plant unit from a cold shutdown state to a power operation state will experience a transition from cold shutdown to hot standby to power operation mode.

[0121] Starting a nuclear power plant unit from a hot shutdown state to a power operation state will experience a transition from hot shutdown to hot standby to power operation mode.

[0122] The shutdown process refers to the process of reducing power from the power operation state to the shutdown state. Specifically, the conversion relationship between various operation modes during the shutdown process of the nuclear power plant is determined, including the following two situations:

[0123] Shutting down a nuclear power plant unit from a power operation state to a hot shutdown state will involve a transition from a power operation mode directly to a hot shutdown mode.

[0124] Shutting down a nuclear power plant unit from a power operation state to a cold shutdown state will involve a transition from a power operation mode directly to a cold shutdown mode.

[0125] S3, determining the operating status of the system functions in each operating mode.

[0126] Before determining the operating status of the system functions in each operating mode in step S3, the method further includes: determining the system and the corresponding system functions in each operating mode according to the start-stop operation sequence.

[0127] According to the start-stop operation sequence, the main system functions, similar functions, and parameters involved in the start-stop process of the unit can be combined. For example, for the control rod system, the control rod lifting / dropping operation will affect the unit temperature parameters and the unit thermal power level. Therefore, the operations related to the control rod and the related parameter adjustments that may be affected can be combined into the "control rod adjustment function".

[0128] Taking the gas-cooled micro-reactor in this embodiment as an example, the main system functions involved in the start-up and shutdown process of the gas-cooled micro-reactor include: the heat sink function corresponding to the heat sink system, the helium filling and exhaust function corresponding to the main loop system, the helium turbine function corresponding to the main loop system, the helium sampling, monitoring and purification function corresponding to the auxiliary system, and the control rod adjustment function corresponding to the reactor control system.

[0129] For each of the system functions determined in step S2, analyze and determine its operating status in each mode. Taking the startup process of the air-cooled micro reactor as an example, the operating status of the system functions in each operating mode is shown in Table 2 below:

[0130] Table 2 Operating status of system functions in each operating mode during the startup of the gas-cooled micro reactor

[0131]

[0132] In the cold shutdown mode, the heat sink function and the helium turbine function are in shutdown state, and the control rod adjustment function is in the cold shutdown rod position. In the hot shutdown mode, the heat sink function and the helium turbine function are in shutdown state, and the control rod adjustment function is in the hot shutdown rod position. The hot standby operation modes include critical state, low power state, self-sustaining state and auxiliary power state. In the critical state, the heat sink function is in the start-up state, the helium turbine function is in the state of starting the turbine to the preset target speed, and the control rod adjustment function is in the critical rod position of the critical rod lifting mode. In the low power state and the plant power state, the heat sink function is in the automatic control state, the helium turbine function is in the preset target speed state, and the control rod adjustment function is in the rod lifting mode according to the temperature-nuclear power curve. In the self-sustaining state, the heat sink function is in the automatic control state, the helium turbine function is in the self-sustaining mode, and the control rod adjustment function is in the rod lifting mode according to the temperature-nuclear power curve, and the rod position is changed according to the "temperature-nuclear power" curve; in the power operation mode, the heat sink function is in the automatic control state, the helium turbine function is in the load tracking mode, and the control rod adjustment function is in the load tracking mode.

[0133] S4, based on the conversion relationship and the operating status of the system functions, conduct demand analysis on the system functions.

[0134] Combined with the mode conversion relationship determined in step S2 and the operating status of the system function determined in step S3, specific functional requirements are proposed for the functional goals that the nuclear power plant should achieve during startup and shutdown in different modes. For example, during the period from cold shutdown to power operation, the adjustment function of the control rod has the following requirements:

[0135] In the cold shutdown mode, the control rods should maintain the cold shutdown rod position; in the hot shutdown mode, the control rods should maintain the hot shutdown rod position; during the conversion from hot shutdown to hot standby mode, the control rods should have the ability to automatically lift the rods. First, the rods need to be automatically lifted to the critical level, and then they are gradually lifted to the rod position corresponding to the plant power according to the rod lifting procedure to reach the plant power state; during the conversion from hot standby to power operation mode, the control rods should have the ability to automatically adjust the control rod position according to the requirements of the coordinated control system; during the conversion from hot shutdown mode to cold shutdown mode during the shutdown process, the control rods should be dropped from the hot shutdown rod position to the cold shutdown rod position accordingly.

[0136] S5, based on the demand analysis results, determine the start-stop sequence control logic function group and form the start-stop operation strategy of the nuclear power plant.

[0137] The above steps S1 to S4 determine the basic operation strategy of the nuclear power plant start-up and shutdown process. In order to achieve the goal of automatic start-up and shutdown, the APS sequential control logic is used to set the start-up and shutdown process, and the entire start-up and shutdown process is set into several functional groups. Functional groups often represent the control or monitoring of a class of functions. Based on the functional analysis of each system function in different mode conversion processes in S4, various functional requirements are sorted out and corresponding functional groups are set.

[0138] For example, in the process from cold shutdown to the critical state in hot standby mode in this embodiment, according to the operation strategy objectives, it is necessary to first start the heat sink system to provide an overall cold source for starting the machine, and then fill the main circuit with an appropriate amount of helium as a medium, and then start the helium turbine to promote the circulation of helium. At this time, it should also be considered to determine whether the purity of the helium medium meets the requirements through sampling, and purify it according to needs. After the above steps are ready, it is considered that the relevant operations of lifting the rod to criticality can be performed, thereby achieving hot standby mode. The functional groups set at this stage include: a first functional group for starting the heat sink system, a second functional group for starting the filling and exhausting system, a third functional group for starting the helium turbine to a preset target speed state, a fourth functional group for helium sampling monitoring and purification, and a fifth functional group for lifting the rod to a critical state. Among them, the first functional group includes five functional subgroups, namely, the first functional subgroup for starting the heat sink small flow cycle, the second functional subgroup for operating the heat sink compressor circuit, the third functional subgroup for operating the heat sink vacuum pump circuit, the fourth functional subgroup for operating the heat sink intercooler and precooler circuit, and the fifth functional subgroup for operating the heat sink generator circuit.

[0139] Furthermore, after determining the start-stop sequence control logic function group, the method further includes: analyzing the logical relationship between each function group.

[0140] Combined with the function group setting in step S5, the logical execution relationship of each function group in the start-stop process is further analyzed according to the basic operation strategy to construct the overall APS sequential control logic framework of the self-start-stop strategy. The specific process is as follows:

[0141] First, according to the start-stop strategy, determine the execution order relationship between the functional groups. For example, the core will not become reactive and have reactor power until the control rod reaches criticality, so that nuclear heating can be performed to provide a heat source. Therefore, the execution order of the "rod raising and nuclear heating" functional group should be after the "rod raising and reaching criticality" functional group. Secondly, determine the execution relationship of the functional groups. For example, analyze the permissible conditions, completion conditions, and possible skip conditions for the execution of each functional group. Finally, improve the logical relationship between the functional groups. For example, the completion conditions of the previous functional group should be a necessary condition for the permissible conditions of the next functional group, and the skip conditions should specifically indicate the jump target functional group.

[0142] Taking the critical state process from cold shutdown to hot standby mode in this embodiment as an example, according to the start-stop strategy, it can be analyzed that the five functional groups are executed in sequence. Specifically, the first functional group is the first functional group in the startup process, and its permission conditions include the completion of the preliminary self-check, the issuance of the self-start and stop permission command, the reactor is subcritical, the control rod is in the shutdown rod position, the turbine is shut down, and the temperature and pressure of the main circuit are within the specified range; this functional group is realized by sequentially starting the heat sink small flow cycle, putting the heat sink compressor circuit into operation, putting the heat sink vacuum pump circuit into operation, putting the heat sink intercooler into operation, the precooler circuit, and putting the heat sink generator circuit into operation; the final functional group completion condition is that the valves of each branch of the heat sink system have been opened and the heat sink system has been put into operation. The permission condition of the second functional group is the completion condition of the first functional group; this functional group realizes the goal of automatically adjusting the main system pressure value to the required value by starting the charging and discharging system and setting the charging and discharging valves to the automatic mode; the final functional group completion condition is that the pressure of the first circuit reaches the initial pressure value. The permissible conditions of the third functional group are the completion conditions of the second functional group and the helium turbine should be in the shutdown state; this functional group is realized by putting electromagnetic bearings into operation, opening the anti-surge valve and putting it into automatic operation, executing the speed start curve to increase the speed to N1, etc.; the completion condition of the final functional group is that the speed of the helium turbine reaches the N1 value. The permissible conditions of the fourth functional group are the completion conditions of the third functional group and the helium purity does not meet the system design requirements; this functional group is realized by performing helium sampling monitoring and starting the relevant valves of the purification circuit; the completion condition of the final functional group is that the helium purity meets the system requirements. If the helium purity meets the requirements when executing the fourth functional group, then the step can be skipped at this time, skipping this functional group and directly executing the subsequent functional groups. The permissible conditions of the fifth functional group are the completion conditions of the fourth functional group and the control rod is in the shutdown rod position; this functional group is realized by lifting the control rod to the critical rod position; the completion condition of the final functional group is that the reactor reaches the critical state.

[0143] According to the above analysis logic, the execution logic of each functional group in the entire start-up and shutdown process of the nuclear power plant can be analyzed to form a preliminary start-up and shutdown design plan.

[0144] like Figure 2 As shown, in another embodiment of the present invention, after executing step S5 to form the start-stop operation strategy of the nuclear power plant, step S6 is continued to be executed to determine whether the start-stop operation strategy is reasonable through the simulation platform.

[0145] Specifically, based on the relevant simulation platform, the sequential control logic of the above-mentioned functional groups is simulated and tested to determine whether the start-stop operation strategy is reasonable. During the execution process, the equipment status changes corresponding to each step of each functional group and the curve changes of related parameters are checked to determine whether the start-stop operation strategy meets the expected requirements. If it meets the requirements, the scheme is considered reasonable, which proves that the start-stop operation strategy analysis method is effective and feasible; if it does not meet the requirements, the start-stop operation strategy is considered unreasonable, and step S7 is executed to re-determine the operating status of the system and the corresponding system functions under each operating mode. The process includes: re-checking and determining the operating status of the system and functions under each operating mode, checking whether the original design has omissions or design errors; proposing new demand analysis for the transformation of the system and functions between different operating states; adjusting the operation content of the functional group, and verifying and confirming again until it meets the expected requirements.

[0146] This method automatically determines the operating mode by establishing a logical equation, and ensures the comprehensiveness of the function group setting and the consistency of the system analysis by analyzing the system status and functional requirements in each mode conversion process in detail. In addition, the APS instructions are used to automate the strategy steps to achieve automatic start and stop of the unit and optimize the operation process. This method can be applied to newly built nuclear power units, and can also be used to guide the design and modification of existing nuclear power units in terms of automatic start and stop operation.

[0147] In order to achieve the same purpose as the above method, the present invention proposes an analysis device for the start-up and shutdown operation strategies of a nuclear power plant.

[0148] like Figure 3 Schematic diagram of an analysis device for the start-stop operation strategy of a nuclear power plant according to an embodiment of the present invention is shown in FIG. 1 , the device comprises: an identification module 31 , a first determination module 32 , a second determination module 33 , a demand analysis module 34 and a generation module 35 .

[0149] The identification module 31 is used to identify the operation mode during the start-up and shutdown process of the nuclear power plant.

[0150] Furthermore, the identification module 31 is used to:

[0151] Set the corresponding logic equation for each operation mode.

[0152] The operating parameters of the nuclear power plant during startup and shutdown are obtained, and the operating parameters include one or more of reactivity, thermal power, and average core temperature.

[0153] The operating parameters are input into the logistic equations to identify the operating mode of the nuclear power plant.

[0154] Furthermore, the operation modes include power operation, hot standby, hot shutdown, cold shutdown and maintenance shutdown.

[0155] The logic equation corresponding to the power operation is: M1 = thermal power > 30%.

[0156] The logic equation corresponding to hot standby is: Where, “·” represents the AND operator, T1 is the minimum critical temperature, P6 represents the intermediate range neutron flux > 10-5% Pn, is the non-value of the thermal shutdown signal value, is the non-value of the cold shutdown signal value, A non-value representing the maintenance trip signal value.

[0157] The logic equation corresponding to the thermal shutdown is: Among them, T2 is the lowest average temperature that provides sufficient residual reactivity in the core for a rod ejection accident. Indicates that the mid-range neutron flux is ≤10-5%Pn.

[0158] The logic equation corresponding to the cold shutdown is:

[0159] The logic equation corresponding to the maintenance outage is: T3 is the upper limit temperature at which material replacement and maintenance operations can be performed.

[0160] The first determination module 32 is used to determine the conversion relationship between various operation modes during the start-up and shutdown process of the nuclear power plant.

[0161] Furthermore, the first determining module 32 is used to:

[0162] Starting a nuclear power plant unit from a cold shutdown state to a power operation state will experience a transition from cold shutdown to hot standby to power operation mode.

[0163] Starting a nuclear power plant unit from a hot shutdown state to a power operation state will experience a transition from hot shutdown to hot standby to power operation mode.

[0164] Furthermore, the first determining module 32 is used to:

[0165] Shutting down a nuclear power plant unit from a power operation state to a hot shutdown state will involve a transition from a power operation mode directly to a hot shutdown mode.

[0166] Shutting down a nuclear power plant unit from a power operation state to a cold shutdown state will involve a transition from a power operation mode directly to a cold shutdown mode.

[0167] Furthermore, before determining the operating status of the system functions under each operating mode, it includes: determining the system and the corresponding system functions under each operating mode according to the start-stop operation sequence, the system including one or more of a heat trap system, a main loop system, an auxiliary system, and a reactor control system, the system function corresponding to the heat trap system is a heat trap function, the system functions corresponding to the main loop system include a helium filling and exhaust function and a helium turbine function, the system functions corresponding to the auxiliary system include a helium sampling and monitoring function and a purification function, and the system function corresponding to the reactor control system is a control rod adjustment function.

[0168] The second determination module 33 is used to determine the operating status of the system function in each operating mode.

[0169] Furthermore, the second determining module 33 is used to:

[0170] In the cold shutdown operation mode, the heat sink function and the helium turbine function are in a shutdown state, and the control rod adjustment function is in the cold shutdown rod position.

[0171] In the hot shutdown operation mode, the heat sink function and the helium turbine function are in a shutdown state, and the control rod adjustment function is in the hot shutdown rod position.

[0172] The hot standby operation modes include critical state, low power state, self-sustaining state and auxiliary power state. In the critical state, the heat sink function is in the start-up state, the helium turbine function is in the state of starting the turbine to the preset target speed, and the control rod adjustment function is in the critical rod position of the critical rod lifting mode.

[0173] In the low power state and the auxiliary power state, the heat sink function is in the automatic control state, the helium turbine function is in the preset target speed state, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve.

[0174] In the self-sustaining state, the heat sink function is in automatic control, the helium turbine function is in self-sustaining mode, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve.

[0175] In the power operation mode, the heat sink function is in automatic control, the helium turbine function is in load following mode, and the control rod adjustment function is in load following mode.

[0176] The demand analysis module 34 is used to perform demand analysis on system functions based on the conversion relationship and the operating status of the system functions.

[0177] The generation module 35 is used to determine the start-stop sequence control logic function group based on the demand analysis result and form the start-stop operation strategy of the nuclear power plant.

[0178] Furthermore, it also includes:

[0179] The simulation platform is used to determine whether the start-stop operation strategy is reasonable.

[0180] If the start-stop operation strategy is unreasonable, the operating status of the system functions in each operating mode will be re-determined.

[0181] Furthermore, based on the demand analysis result, a sequential control logic function group in the critical state process from cold shutdown to hot standby mode is determined, including:

[0182] The first functional group is used to start the heat trap system, the second functional group is used to start the filling and exhaust system, the third functional group is used to start the helium turbine to a preset target speed state, the fourth functional group is used for helium sampling monitoring and purification, and the fifth functional group is used to raise the rod to a critical state.

[0183] The first functional group includes a first functional subgroup for starting a heat sink low-flow cycle, a second functional subgroup for operating a heat sink compressor circuit, a third functional subgroup for operating a heat sink vacuum pump circuit, a fourth functional subgroup for operating a heat sink intercooler and precooler circuit, and a fifth functional subgroup for operating a heat sink generator circuit.

[0184] Furthermore, after determining the start-stop sequence control logic function group, the method further includes: analyzing the logical relationship between each function group.

[0185] Furthermore, the first function group, the second function group, the third function group, the fourth function group and the fifth function group are in a logical relationship of sequential execution.

[0186] It should be understood that the description of an analysis device for a start-stop operation strategy of a nuclear power plant is consistent with the description of a corresponding analysis method for a start-stop operation strategy of a nuclear power plant, so this embodiment will not be repeated.

[0187] In summary, it can be seen from the above description that the above embodiments of the present invention achieve the following technical effects:

[0188] 1. The present invention determines the conversion relationship between various operating modes during the start-up and shutdown process of the nuclear power plant, and the operating status of the system functions under each operating mode. Based on the conversion relationship and the operating status of the system functions, the system functions are analyzed for demand and the start-up and shutdown sequential control logic function group is determined, and finally the start-up and shutdown operation strategy of the nuclear power plant is formed. Compared with designing the start-up and shutdown strategy according to the step sequence, this method can better ensure the integrity and standardization of the start-up and shutdown strategy.

[0189] 2. The present invention sets corresponding logic equations for the operating modes of nuclear power plants, calculates operating parameters using the logic equations, and automatically identifies and calculates the operating modes of nuclear power plants. Compared with designing start-stop strategies in sequence, the present invention can determine the operating modes of nuclear power plants more quickly and accurately, laying an important foundation for subsequent analysis of the conversion relationship of operating modes and analysis of the operating status of system functions, and can ensure that the start-stop operation strategies of nuclear power plants are more in line with actual operating requirements, thereby improving the operating efficiency and safety of nuclear power plants.

[0190] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0191] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0192] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, which can be embodied in any computer-readable medium for use by an instruction execution system, apparatus or device (such as a computer-based system, a system including a processor or other system that can fetch instructions from an instruction execution system, apparatus or device and execute instructions), or used in combination with these instruction execution systems, apparatuses or devices.

[0193] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0194] It should be noted that, in the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

Claims

1. A method for analyzing the start-up and shutdown operation strategy of a nuclear power plant, characterized in that: include: Identify the operating modes during the startup and shutdown of nuclear power plants; Determine the conversion relationship between various operating modes during the start-up and shutdown process of the nuclear power plant; Determine the operating status of the system functions in each of the operating modes; Based on the conversion relationship and the operating status of the system function, performing demand analysis on the system function; Based on the demand analysis result, a start-stop sequential control logic function group is determined, and a start-stop operation strategy of the nuclear power plant is formed.

2. The method according to claim 1, characterized in that: Also includes: Determine whether the start-stop operation strategy is reasonable through the simulation platform; If the start-stop operation strategy is unreasonable, the operation status of the system functions in each operation mode is re-determined.

3. The method according to claim 1, characterized in that Identify the operation modes during the startup and shutdown of nuclear power plants, including: Setting corresponding logic equations for each operation mode; Acquiring operating parameters during the start-up and shutdown process of the nuclear power plant, wherein the operating parameters include one or more of reactivity, thermal power, and average core temperature; The operating parameters are input into the logic equation to identify an operating mode of the nuclear power plant.

4. The method according to claim 3, characterized in that The operation modes include power operation, hot standby, hot shutdown, cold shutdown and maintenance shutdown. The logic equation corresponding to the power operation is: M1 = thermal power > 30%; The logic equation corresponding to the hot standby is: Where "·" represents the AND operator, T1 is the minimum critical temperature, and P6 represents the intermediate range neutron flux > 10 -5 %Pn, is the non-value of the thermal shutdown signal value, is the non-value of the cold shutdown signal value, It is the non-value of the maintenance trip signal value; The logic equation corresponding to the thermal shutdown is: Among them, T2 is the lowest average temperature that provides sufficient residual reactivity in the core for a rod ejection accident. For the intermediate range neutron flux ≤ 10 -5 %Pn; The logic equation corresponding to the cold shutdown is: The logic equation corresponding to the maintenance shutdown is: T3 is the upper limit temperature at which material replacement and maintenance operations can be performed.

5. The method according to claim 4, characterized in that Determine the conversion relationship between various operating modes during the startup process of the nuclear power plant, including: Starting the nuclear power plant unit from the cold shutdown state to the power operation state will experience a transition from the cold shutdown mode to the hot standby mode to the power operation mode; Starting the nuclear power plant unit from the hot shutdown state to the power operation state will experience a transition from the hot shutdown mode to the hot standby mode to the power operation mode.

6. The method according to claim 4, characterized in that Determine the conversion relationship between various operating modes during the shutdown of the nuclear power plant, including: Shutting down the nuclear power plant unit from the power operation state to the hot shutdown state will experience a transition directly from the power operation mode to the hot shutdown mode; Shutting down the nuclear power plant unit from the power operation state to the cold shutdown state will experience a transition directly from the power operation mode to the cold shutdown mode.

7. The method according to any one of claims 4 to 6, characterized in that: Before determining the operating status of the system functions under the various operating modes, the method includes: determining the systems and corresponding system functions under the various operating modes according to the start-stop operation sequence, the systems including one or more of a heat trap system, a main loop system, an auxiliary system, and a reactor control system, the system function corresponding to the heat trap system is a heat trap function, the system functions corresponding to the main loop system include a helium filling and exhaust function and a helium turbine function, the system functions corresponding to the auxiliary system include a helium sampling and monitoring function and a purification function, and the system function corresponding to the reactor control system is a control rod adjustment function.

8. The method according to claim 7, characterized in that Determining the operating status of the system functions in each operating mode includes: In the cold shutdown operation mode, the heat sink function and the helium turbine function are in a shutdown state, and the control rod adjustment function is in a cold shutdown rod position; In the thermal shutdown operation mode, the heat sink function and the helium turbine function are in a shutdown state, and the control rod adjustment function is in a thermal shutdown rod position; The hot standby operation mode includes a critical state, a low power state, a self-sustaining state and an auxiliary power state. In the critical state, the heat sink function is in a startup state, the helium turbine function is in a state of starting the turbine to a preset target speed, and the control rod adjustment function is in a critical rod position of a critical rod lifting mode. In the low power state and the auxiliary power state, the heat sink function is in the automatic control state, the helium turbine function is in the preset target speed state, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve. In the self-sustaining state, the heat sink function is in an automatic control state, the helium turbine function is in a self-sustaining mode, and the control rod adjustment function is in a rod raising mode according to a temperature-nuclear power curve. In the power operation mode, the heat sink function is in automatic control state, the helium turbine function is in load following mode, and the control rod adjustment function is in the load following mode.

9. The method according to claim 8, characterized in that Determining a sequential control logic function group in a process from the cold shutdown to the critical state in the hot standby mode based on the demand analysis result includes: a first functional group for starting the heat trap system, a second functional group for starting the filling and exhausting system, a third functional group for starting the helium turbine to the preset target speed state, a fourth functional group for helium sampling monitoring and purification, and a fifth functional group for raising the rod to a critical state, The first functional group includes a first functional subgroup for starting a heat sink low-flow cycle, a second functional subgroup for operating a heat sink compressor circuit, a third functional subgroup for operating a heat sink vacuum pump circuit, a fourth functional subgroup for operating a heat sink intercooler and precooler circuit, and a fifth functional subgroup for operating a heat sink generator circuit.

10. The method according to claim 9, characterized in that After determining the start-stop sequence control logic function group, it also includes: analyzing the logical relationship between each function group.

11. The method according to claim 10, characterized in that The first function group, the second function group, the third function group, the fourth function group and the fifth function group are in a logical relationship of sequential execution.

12. An analysis device for the start-up and shutdown operation strategy of a nuclear power plant, characterized in that: include: Identification module, used to identify the operation mode during the start-up and shutdown process of the nuclear power plant; The first determination module is used to determine the conversion relationship between various operation modes during the start-up and shutdown process of the nuclear power plant; A second determination module is used to determine the operating status of the system function in each operating mode; A demand analysis module, used for performing demand analysis on the system function based on the conversion relationship and the operating status of the system function; The generation module is used to determine the start-stop sequence control logic function group based on the demand analysis result and form the start-stop operation strategy of the nuclear power plant.

13. The device according to claim 12, characterized in that Also includes: Determine whether the start-stop operation strategy is reasonable through the simulation platform; If the start-stop operation strategy is unreasonable, the operation status of the system functions in each operation mode is re-determined.

14. The device according to claim 12, characterized in that The identification module is used to: Setting corresponding logic equations for each operation mode; Acquiring operating parameters during the start-up and shutdown process of the nuclear power plant, wherein the operating parameters include one or more of reactivity, thermal power, and average core temperature; The operating parameters are input into the logic equation to identify an operating mode of the nuclear power plant.

15. The device according to claim 14, characterized in that The operation modes include power operation, hot standby, hot shutdown, cold shutdown and maintenance shutdown. The logic equation corresponding to the power operation is: M1 = thermal power > 30%; The logic equation corresponding to the hot standby is: Where "·" represents the AND operator, T1 is the minimum critical temperature, and P6 represents the intermediate range neutron flux > 10 -5 %Pn, is the non-value of the thermal shutdown signal value, is the non-value of the cold shutdown signal value, It is the non-value of the maintenance trip signal value; The logic equation corresponding to the thermal shutdown is: Among them, T2 is the lowest average temperature that provides sufficient residual reactivity in the core for a rod ejection accident. Indicates that the intermediate range neutron flux is ≤10 -5 %Pn; The logic equation corresponding to the cold shutdown is: The logic equation corresponding to the maintenance shutdown is: T3 is the upper limit temperature at which material replacement and maintenance operations can be performed.

16. The device according to claim 15, characterized in that The first determining module is used to: Starting the nuclear power plant unit from the cold shutdown state to the power operation state will experience a transition from the cold shutdown mode to the hot standby mode to the power operation mode; Starting the nuclear power plant unit from the hot shutdown state to the power operation state will experience a transition from the hot shutdown mode to the hot standby mode to the power operation mode.

17. The device according to claim 15, characterized in that The first determining module is used to: Shutting down the nuclear power plant unit from the power operation state to the hot shutdown state will experience a transition directly from the power operation mode to the hot shutdown mode; Shutting down the nuclear power plant unit from the power operation state to the cold shutdown state will experience a transition directly from the power operation mode to the cold shutdown mode.

18. The device according to any one of claims 15 to 17, characterized in that Before determining the operating status of the system functions under the various operating modes, the method includes: determining the systems and corresponding system functions under the various operating modes according to the start-stop operation sequence, the systems including one or more of a heat trap system, a main loop system, an auxiliary system, and a reactor control system, the system function corresponding to the heat trap system is a heat trap function, the system functions corresponding to the main loop system include a helium filling and exhaust function and a helium turbine function, the system functions corresponding to the auxiliary system include a helium sampling and monitoring function and a purification function, and the system function corresponding to the reactor control system is a control rod adjustment function.

19. The device according to claim 18, characterized in that The second determining module is used to: In the cold shutdown operation mode, the heat sink function and the helium turbine function are in a shutdown state, and the control rod adjustment function is in a cold shutdown rod position; In the thermal shutdown operation mode, the heat sink function and the helium turbine function are in a shutdown state, and the control rod adjustment function is in a thermal shutdown rod position; The hot standby operation mode includes a critical state, a low power state, a self-sustaining state and an auxiliary power state. In the critical state, the heat sink function is in a startup state, the helium turbine function is in a state of starting the turbine to a preset target speed, and the control rod adjustment function is in a critical rod position of a critical rod lifting mode. In the low power state and the auxiliary power state, the heat sink function is in the automatic control state, the helium turbine function is in the preset target speed state, and the control rod adjustment function is in the rod raising mode according to the temperature-nuclear power curve. In the self-sustaining state, the heat sink function is in an automatic control state, the helium turbine function is in a self-sustaining mode, and the control rod adjustment function is in a rod raising mode according to a temperature-nuclear power curve. In the power operation mode, the heat sink function is in automatic control state, the helium turbine function is in load following mode, and the control rod adjustment function is in the load following mode.

20. The device according to claim 19, characterized in that Determining a sequential control logic function group in a process from the cold shutdown to the critical state in the hot standby mode based on the demand analysis result includes: a first functional group for starting the heat trap system, a second functional group for starting the filling and exhausting system, a third functional group for starting the helium turbine to the preset target speed state, a fourth functional group for helium sampling monitoring and purification, and a fifth functional group for raising the rod to a critical state, The first functional group includes a first functional subgroup for starting a heat sink low-flow cycle, a second functional subgroup for operating a heat sink compressor circuit, a third functional subgroup for operating a heat sink vacuum pump circuit, a fourth functional subgroup for operating a heat sink intercooler and precooler circuit, and a fifth functional subgroup for operating a heat sink generator circuit.

21. The device according to claim 20, characterized in that After determining the start-stop sequence control logic function group, it also includes: analyzing the logical relationship between each function group.

22. The device according to claim 21, characterized in that The first function group, the second function group, the third function group, the fourth function group and the fifth function group are in a logical relationship of sequential execution.

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