Online protection method, device, medium and equipment for reactor core

Abstract

The invention discloses an online protection method and device for a reactor core, a medium and equipment, and the method comprises the steps: obtaining the rod position information of each control rod in a reactor in a current state, and obtaining a whole reactor power reconstruction coefficient in the current state according to the rod position information and a preset rod state database; based on the whole reactor power reconstruction coefficient, the detector current signal and the power plant working condition signal in the current state, the fuel assembly line power density and the deviation nucleation boiling ratio of each channel and the fuel assembly line power density and the deviation nucleation boiling ratio of the whole reactor are obtained through calculation; and comparing the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole reactor with a preset linear power density threshold value, the deviation nucleation boiling ratio of each channel, the deviation nucleation boiling ratio of the whole reactor and a preset boiling ratio threshold value, and determining and outputting a pre-protection signal and protection information. The reactor power reconstruction coefficient participates in protection parameter calculation, so that the accuracy and reliability of a protection signal are improved, and the safety of a power plant is improved.

Description

Technical Field

[0001] The present invention relates to the field of nuclear power technology, and in particular to an online protection method, device, medium and equipment for a reactor core. Background Art

[0002] A nuclear power plant is a power plant that uses the energy released by nuclear fission or nuclear fusion reactions to generate electricity. The reactor in a nuclear power plant is a device that starts, controls and maintains the nuclear fission or nuclear fusion chain reaction. The core is the heart of the reactor and the source of its power.

[0003] During the operation of the reactor, the state of the reactor core is directly related to the reactor safety. Therefore, the state parameters of the reactor core are the most fundamental and important parameters to characterize the reactor safety. Among them, the fuel assembly linear power density (LPD) and deviation from nucleate boiling ratio (DNBR) are the two most critical parameters.

[0004] When a pressurized water reactor is in operation, the core is required to work in the nucleate boiling heat transfer mode, at which the heat transfer efficiency is the highest. However, when certain transients occur and cause the local heat flux in the reactor to increase to a certain extent, the bubbles generated on the cladding wall will connect together before leaving the wall to form a vapor film, which increases the thermal resistance and reduces the heat transfer coefficient, causing the cladding temperature to rise sharply, and eventually leading to excessive fuel temperature and meltdown. This situation is called deviation from nucleate boiling (DNB). To ensure the safety of the reactor, the design requires that the maximum heat flux on the surface of the fuel element is less than the critical heat flux. To quantitatively express this requirement, the deviation from nucleate boiling ratio (DNBR) is introduced. In order to avoid excessively high core linear power density, the linear power density (LPD) of the fuel assembly is introduced. The linear power density refers to the power borne by the fuel assembly per unit length. It is an important parameter for measuring the power distribution of the reactor fuel assembly and has a direct impact on the thermal hydraulics and safe operation of the reactor.

[0005] The deviation from nucleate boiling and the linear power density of the fuel assembly are usually calculated by using the measured current of the self-powered neutron detector of the core measurement system and the measured operating parameters of the main coolant system of the reactor. The measured current of the detector and the measured operating parameters of the main coolant system used in this method are not real-time parameters. After obtaining the measured current and the measured operating parameters of the coolant system at a certain moment, the deviation from nucleate boiling and the linear power density of the fuel assembly within a period of time are calculated based on these parameters. Therefore, the deviation from nucleate boiling and the linear power density of the fuel assembly calculated by the existing method have relatively low accuracy. Summary of the invention

[0006] In view of this, the present invention provides an online protection method, device, medium and equipment for a reactor core, the main purpose of which is to solve the problem of low accuracy of deviation from nucleate boiling and fuel assembly linear power density calculated by existing methods.

[0007] According to one aspect of the present application, there is provided an online protection method for a reactor core, the method comprising:

[0008] Obtaining rod position information of each control rod in the reactor in the current state, and obtaining a full-stack power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database;

[0009] Acquire the detector current signal and the power plant operating condition signal of the reactor, and calculate the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the full stack power reconstruction coefficient in the current state, the detector current signal and the power plant operating condition signal;

[0010] Based on the power plant operating condition signal, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack, respectively calculating the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire stack;

[0011] The linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole stack and a preset linear power density threshold are compared, and a pre-protection signal and protection information of the linear power density are determined and output; the deviation from the nucleate boiling ratio of each channel, the deviation from the nucleate boiling ratio of the whole stack and a preset boiling ratio threshold are compared, and a pre-protection signal and protection information of the deviation from the nucleate boiling ratio are determined and output.

[0012] Optionally, obtaining the full stack power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database includes:

[0013] According to the rod position information of each control rod, traverse each preset rod state in a preset rod state database to obtain two preset rod states that are close to the rod position information of the control rod in the current state;

[0014] The power reconstruction coefficients of the two preset rod states are obtained, and interpolation calculation is performed based on the power reconstruction coefficients of the two preset rod states to obtain the power reconstruction coefficient of the whole stack in the current state.

[0015] Optionally, the calculating of the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the whole stack power reconstruction coefficient, the detector current signal and the power plant operating condition signal in the current state includes:

[0016] Obtaining the detector current signal and the power plant operating condition signal corresponding to each channel, and obtaining the power reconstruction coefficient corresponding to the node included in each channel from the full stack power reconstruction coefficient;

[0017] Based on the power reconstruction coefficient corresponding to the nodes contained in each channel, the detector current signal corresponding to each channel and the power plant operating condition signal, the linear power density of the fuel assembly of each channel is calculated by the node weighted power calculation method;

[0018] The total detector current signal and the total power plant operating condition signal corresponding to all channels are obtained, and based on the full-stack power reconstruction coefficient, the total detector current signal and the total power plant operating condition signal, the fuel assembly linear power density of the full-stack is calculated through a block weighted power calculation method.

[0019] Optionally, the power plant operating condition signal includes: fuel data, cooling data, reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed; the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack are calculated based on the power plant operating condition signal, the fuel assembly linear power density of each channel, and the fuel assembly linear power density of the whole stack, respectively, including:

[0020] Obtaining fuel data and total cooling data, calculating the average fuel enrichment based on the fuel data, and calculating based on the total cooling data and the linear power density of the fuel assembly of the entire stack to obtain the axial hot spot distribution and the nuclear enthalpy rise factor;

[0021] Based on the average fuel enrichment, the axial hot spot distribution, the nuclear enthalpy rise factor, the total detector current signal and the total power plant operating condition signal, a physical-thermal coupling calculation method is used to obtain the core thermal power;

[0022] Acquire reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed, and calculate thermal hydraulic parameters based on the reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed;

[0023] Acquire cooling data of each channel, calculate based on the cooling data of each channel and the linear power density of the fuel assembly to obtain the nuclear enthalpy rise of each channel, obtain the mass flow rate correction factor of each channel, and calculate the deviation from nucleate boiling ratio of each channel based on the core thermal power, thermal hydraulic parameters, the nuclear enthalpy rise and mass flow rate correction factor of each channel and the boiling curve relationship;

[0024] The total nuclear enthalpy rise is calculated based on the total cooling data and the linear power density of the fuel assembly of the whole stack, and the total mass flow rate correction factor is obtained. The deviation from nucleate boiling ratio of the whole stack is calculated based on the core thermal power, thermal-hydraulic parameters, the total nuclear enthalpy rise and the total mass flow rate correction factor and the boiling curve relationship.

[0025] Optionally, the preset linear power density threshold comprises a first linear power density threshold and a second linear power threshold; the comparing the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the entire stack and the preset linear power density threshold, determining and outputting the pre-protection signal and protection information of the linear power density comprises:

[0026] Performing a logical OR calculation on the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack to obtain a first calculation result;

[0027] When the first calculation result is greater than or equal to the first line power density threshold and less than the second line power density threshold, a line power density pre-protection signal is output; when the first calculation result is greater than or equal to the second line power density threshold, a line power density protection signal is output.

[0028] Optionally, the preset boiling ratio threshold includes a first boiling ratio threshold and a second boiling ratio threshold; the comparing the deviation from nucleate boiling ratio of each channel, the deviation from nucleate boiling ratio of the whole stack and the preset boiling ratio threshold, determining and outputting the pre-protection signal and protection information of the deviation from nucleate boiling ratio, comprises:

[0029] Performing a logical OR calculation on the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire reactor to obtain a second calculation result;

[0030] When the second calculation result is greater than or equal to the first boiling ratio threshold and less than the second boiling ratio threshold, a pre-protection signal deviating from the nucleate boiling ratio is output; when the second calculation result is greater than or equal to the boiling ratio threshold, a protection signal deviating from the nucleate boiling ratio is output.

[0031] Optionally, before obtaining the rod position information of each control rod in the reactor in the current state, the online protection method of the reactor core further includes:

[0032] Divide the entire reactor into multiple grids in radial and axial directions;

[0033] Obtaining rod position information, detector current signals, and power plant operating condition signals corresponding to control rods in multiple rod states, and obtaining a power reconstruction coefficient of each grid in each rod state by using an online power distribution algorithm based on the detector current signals and the power plant operating condition signals;

[0034] Based on the rod position information under each rod state and the power reconstruction coefficient of each grid, a preset rod state database is generated.

[0035] According to another aspect of the present application, there is provided an online protection device for a reactor core, comprising:

[0036] A full-stack power reconstruction coefficient acquisition module is used to obtain the rod position information of each control rod in the reactor in the current state, and obtain the full-stack power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database;

[0037] A fuel assembly linear power density calculation module is used to obtain the detector current signal of the reactor and the power plant operating signal, and calculate the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the full stack power reconstruction coefficient in the current state, the detector current signal and the power plant operating signal;

[0038] a deviation from nucleate boiling ratio calculation module, for calculating the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack respectively based on the power plant operating condition signal, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack;

[0039] The protection signal determination module is used to compare the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole stack and a preset linear power density threshold, determine and output a pre-protection signal and protection information of the linear power density, compare the deviation from the nucleate boiling ratio of each channel, the deviation from the nucleate boiling ratio of the whole stack and a preset boiling ratio threshold, determine and output a pre-protection signal and protection information of the deviation from the nucleate boiling ratio.

[0040] Optionally, the full stack power reconstruction coefficient acquisition module is further used for:

[0041] According to the rod position information of each control rod, traverse each preset rod state in a preset rod state database to obtain two preset rod states that are close to the rod position information of the control rod in the current state;

[0042] The power reconstruction coefficients of the two preset rod states are obtained, and interpolation calculation is performed based on the power reconstruction coefficients of the two preset rod states to obtain the power reconstruction coefficient of the whole stack in the current state.

[0043] Optionally, the fuel assembly line power density calculation module is further used for:

[0044] Obtaining the detector current signal and the power plant operating condition signal corresponding to each channel, and obtaining the power reconstruction coefficient corresponding to the node included in each channel from the full stack power reconstruction coefficient;

[0045] Based on the power reconstruction coefficient corresponding to the nodes contained in each channel, the detector current signal corresponding to each channel and the power plant operating condition signal, the linear power density of the fuel assembly of each channel is calculated by the node weighted power calculation method;

[0046] The total detector current signal and the total power plant operating condition signal corresponding to all channels are obtained, and based on the full-stack power reconstruction coefficient, the total detector current signal and the total power plant operating condition signal, the fuel assembly linear power density of the full-stack is calculated through a block weighted power calculation method.

[0047] Optionally, the deviation from nucleate boiling ratio calculation module is further used for:

[0048] Obtaining fuel data and total cooling data, calculating the average fuel enrichment based on the fuel data, and calculating based on the total cooling data and the linear power density of the fuel assembly of the entire stack to obtain the axial hot spot distribution and the nuclear enthalpy rise factor;

[0049] Based on the average fuel enrichment, the axial hot spot distribution, the nuclear enthalpy rise factor, the total detector current signal and the total power plant operating condition signal, a physical-thermal coupling calculation method is used to obtain the core thermal power;

[0050] Acquire reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed, and calculate thermal hydraulic parameters based on the reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed;

[0051] Acquire cooling data of each channel, calculate based on the cooling data of each channel and the linear power density of the fuel assembly to obtain the nuclear enthalpy rise of each channel, obtain the mass flow rate correction factor of each channel, and calculate the deviation from nucleate boiling ratio of each channel based on the core thermal power, thermal hydraulic parameters, the nuclear enthalpy rise and mass flow rate correction factor of each channel and the boiling curve relationship;

[0052] The total nuclear enthalpy rise is calculated based on the total cooling data and the linear power density of the fuel assembly of the whole stack, and the total mass flow rate correction factor is obtained. The deviation from nucleate boiling ratio of the whole stack is calculated based on the core thermal power, thermal-hydraulic parameters, the total nuclear enthalpy rise and the total mass flow rate correction factor and the boiling curve relationship.

[0053] Optionally, the protection signal determination module is further used to:

[0054] Performing a logical OR calculation on the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack to obtain a first calculation result;

[0055] When the first calculation result is greater than or equal to the first line power density threshold and less than the second line power density threshold, a line power density pre-protection signal is output; when the first calculation result is greater than or equal to the second line power density threshold, a line power density protection signal is output.

[0056] Optionally, the protection signal determination module is further used to:

[0057] Performing a logical OR calculation on the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire reactor to obtain a second calculation result;

[0058] When the second calculation result is greater than or equal to the first boiling ratio threshold and less than the second boiling ratio threshold, a pre-protection signal deviating from the nucleate boiling ratio is output; when the second calculation result is greater than or equal to the boiling ratio threshold, a protection signal deviating from the nucleate boiling ratio is output.

[0059] Optionally, the online protection device for the reactor core further comprises:

[0060] A preset rod state database generation module is used to divide the entire reactor into multiple grids from the radial and axial directions; obtain the rod position information, detector current signals and power plant operating condition signals corresponding to the control rods in multiple rod states, and based on the detector current signals and the power plant operating condition signals, use an online power distribution algorithm to obtain the power reconstruction coefficient of each grid in each rod state; based on the rod position information in each rod state and the power reconstruction coefficient of each grid, generate a preset rod state database.

[0061] According to another aspect of the present application, a storage medium is provided, in which at least one executable instruction is stored, and the executable instruction enables a processor to execute operations corresponding to the above-mentioned online protection method for the reactor core.

[0062] According to another aspect of the present application, a computer device is provided, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus;

[0063] The memory is used to store at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the above-mentioned online protection method for the reactor core.

[0064] By means of the above technical solution, the technical solution provided by the embodiment of the present invention has at least the following advantages:

[0065] The present application provides an online protection method, device, medium and equipment for a reactor core, which obtains the rod position information of each control rod in the reactor in real time under the current state, obtains the reactor power reconstruction coefficient under the current state according to the rod position information of each control rod, calculates according to the reactor power reconstruction coefficient under the current state and the measured detector current signal and the power plant operating condition signal, obtains the fuel assembly linear power density of each channel, the fuel assembly linear power density of the whole stack, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack, realizes the protection of the reactor based on the fuel assembly linear power density and the deviation from nucleate boiling ratio, involves the reactor power reconstruction coefficient in the protection parameter calculation, improves the accuracy and reliability of the protection signal, and improves the safety of the power plant.

[0066] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Also, the same reference symbols are used throughout the accompanying drawings to indicate the same components. In the accompanying drawings:

[0068] Figure 1 A flow chart of an online protection method for a reactor core provided in an embodiment of the present application is shown;

[0069] Figure 2 A flow chart of another online protection method for a reactor core provided in an embodiment of the present application is shown;

[0070] Figure 3 A schematic diagram showing a control rod placement area of ​​an online reactor core protection method provided by an embodiment of the present application;

[0071] Figure 4 A schematic diagram of a detector placement area for an online reactor core protection method provided by an embodiment of the present application is shown;

[0072] Figure 5 A schematic diagram showing the connection between an upper computing device and a lower computing device of an online protection method for a reactor core provided by an embodiment of the present application is shown;

[0073] Figure 6 A block diagram of the composition of an online protection device for a reactor core provided in an embodiment of the present application is shown.

[0074] in,

[0075] Figure 6 In the middle: 602-full stack power reconstruction coefficient acquisition module; 604-fuel assembly linear power density calculation module; 606-deviation from nucleate boiling ratio calculation module; 608-protection signal determination module. DETAILED DESCRIPTION

[0076] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0077] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention application are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0078] In view of the problem that the deviation from nucleate boiling and the linear power density of fuel assemblies calculated by the existing methods are of low accuracy, the embodiment of the present application provides an online protection method for the reactor core, such as Figure 1 As shown, the method includes:

[0079] 102: Obtain rod position information of each control rod in the reactor in the current state, and obtain a full-reactor power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database;

[0080] 104: Obtaining a detector current signal and a power plant operating signal of the reactor, and calculating a fuel assembly linear power density of each channel and a fuel assembly linear power density of the entire stack based on a full stack power reconstruction coefficient, the detector current signal and the power plant operating signal in a current state;

[0081] 106: Based on the power plant operating condition signal, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack are calculated respectively;

[0082] 108: Compare the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole stack and the preset linear power density threshold, determine and output the pre-protection signal and protection information of the linear power density, compare the deviation from the nucleate boiling ratio of each channel, the deviation from the nucleate boiling ratio of the whole stack and the preset boiling ratio threshold, determine and output the pre-protection signal and protection information of the deviation from the nucleate boiling ratio.

[0083] Specifically, the online protection method of the present application consists of two major parts: upper-level fine calculation and lower-level fast calculation. The upper-level calculation compares the rod position of each control rod inserted in the reactor in the current state with the preset rod state database to obtain the full-stack power reconstruction coefficient in the current state, and provides the core power reconstruction coefficient for the lower-level protection calculation; the lower-level calculation is responsible for the detector microcurrent acquisition and the power plant operating condition signal acquisition, and calculates the fuel assembly linear power density of each channel, the fuel assembly linear power density of the whole stack, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack according to the full-stack power reconstruction coefficient, the detector current signal, the power plant operating condition signal, etc., and compares the fuel assembly linear power density of each channel, the fuel assembly linear power density of the whole stack and the preset linear power density threshold, determines the pre-protection signal and protection information of the linear power density, compares the deviation from nucleate boiling ratio of each channel, the deviation from nucleate boiling ratio of the whole stack and the preset boiling ratio threshold, determines the pre-protection signal and protection information of the deviation from nucleate boiling ratio, and provides a protection basis for the operation of the reactor.

[0084] Compared with the prior art, the present application provides an online protection method for a reactor core, which obtains the rod position information of each control rod in the reactor in real time under the current state, obtains the reactor power reconstruction coefficient under the current state according to the rod position information of each control rod, and calculates according to the reactor power reconstruction coefficient under the current state and the measured detector current signal and the power plant operating condition signal to obtain the fuel assembly linear power density of each channel, the fuel assembly linear power density of the entire stack, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire stack, realizes the protection of the reactor based on the fuel assembly linear power density and the deviation from nucleate boiling ratio, involves the reactor power reconstruction coefficient in the protection parameter calculation, improves the accuracy and reliability of the protection signal, and improves the safety of the power plant.

[0085] In one embodiment of the present invention, Figure 2 As shown, according to the rod position information of each control rod and the preset rod state database, the full reactor power reconstruction coefficient in the current state is obtained, including:

[0086] 202: traverse each preset rod state in a preset rod state database according to the rod position information of each control rod, and obtain two preset rod states that are close to the rod position information of the control rod in the current state;

[0087] 204: Obtain power reconstruction coefficients of two preset rod states, perform interpolation calculation based on the power reconstruction coefficients of the two preset rod states, and obtain a full stack power reconstruction coefficient in a current state.

[0088] Specifically, the control rods are inserted into the reactor at a preset position, for example Figure 3As shown. Obtain the rod position information of each control rod inserted in the reactor in the current state, that is, obtain the rod state information of the current state, traverse the preset rod state database, and obtain two preset rod states similar to the rod state information of the current state, such as two preset rod states Ri and Rj adjacent to the current rod state. Then, obtain the full stack power reconstruction coefficients of the two preset rod states, interpolate according to the full stack power reconstruction coefficients corresponding to the two adjacent preset rod states, and interpolate to obtain the full stack power reconstruction coefficient under the current rod state. As a preferred implementation of this embodiment, mean interpolation method or weight interpolation method, etc. are used during interpolation.

[0089] Each preset rod state in the preset rod state database realizes variable state fine tracking calculation based on nuclear power, boron concentration, rod position state, etc. within a set time to obtain the full stack power reconstruction coefficient corresponding to the preset rod state.

[0090] In one embodiment of the present invention, based on the full stack power reconstruction coefficient, the detector current signal and the power plant operating condition signal in the current state, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack are calculated, including:

[0091] Obtain the detector current signal and the power plant operating condition signal corresponding to each channel, and obtain the power reconstruction coefficient corresponding to the node included in each channel from the full stack power reconstruction coefficient;

[0092] Based on the power reconstruction coefficient corresponding to the nodes contained in each channel, the detector current signal corresponding to each channel and the power plant operating condition signal, the linear power density of the fuel assembly of each channel is calculated by the node weighted power calculation method;

[0093] The total detector current signal and the total power plant operating condition signal corresponding to all channels are obtained. Based on the full-stack power reconstruction coefficient, the total detector current signal and the total power plant operating condition signal, the linear power density of the fuel assembly of the whole stack is calculated through the block weighted power calculation method.

[0094] Specifically, the detector is set at a preset position to collect the current signal of the sampling point in the reactor. The setting position of the detector is as follows: Figure 4 As shown. Receive the original current signal of the core detector, perform a smoothing filter combining hardware and software, use the correction filter to eliminate the lag, perform a validity judgment, and obtain a standard detector current signal. Collect the power plant operating signal and rod position signal, perform normalized signal processing, and perform validity judgment to obtain standard power plant operating signals; according to the collected rod position signal, traverse the preset rod state database provided by the upper-level fine calculation to obtain the full-reactor power reconstruction coefficient of the current state.

[0095] According to the standard detector current signal, standard power plant operating condition signal and power reconstruction coefficient of the node contained in the channel in the whole stack power reconstruction coefficient, the LPD-OWN value (fuel assembly linear power density of the channel) of the channel is calculated by the node weighted power calculation technology;

[0096] The standard detector current signals, standard power plant operating condition signals and whole-stack power reconstruction coefficients of all channels of the whole stack are synchronously utilized, and the LPD-AVE value (linear power density of the whole-stack fuel assembly) of each block of the whole stack is calculated through the block weighted power calculation technology.

[0097] In one embodiment of the present invention, the power plant operating condition signal includes: fuel data, cooling data, reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed; based on the power plant operating condition signal, the fuel assembly linear power density of each channel, and the fuel assembly linear power density of the entire stack, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire stack are calculated respectively, including:

[0098] Obtain fuel data and total cooling data, calculate the average fuel enrichment based on the fuel data, and calculate based on the total cooling data and the linear power density of the fuel assembly of the entire stack to obtain the axial hot spot distribution and the nuclear enthalpy rise factor;

[0099] Based on the average fuel enrichment, axial hot spot distribution, nuclear enthalpy rise factor, total detector current signal and total power plant operating condition signal, the core thermal power is obtained by using the physical-thermal coupling calculation method.

[0100] The reactor inlet and outlet temperatures, the pressurizer pressure and the main pump speed are obtained, and the thermal hydraulic parameters are calculated based on the reactor inlet and outlet temperatures, the pressurizer pressure and the main pump speed;

[0101] The cooling data of each channel is obtained, and the nuclear enthalpy rise of each channel is calculated based on the cooling data of each channel and the linear power density of the fuel assembly, and the mass flow rate correction factor of each channel is obtained. Based on the core thermal power, thermal hydraulic parameters, the nuclear enthalpy rise and mass flow rate correction factor of each channel and the boiling curve relationship, the deviation from nucleate boiling ratio of each channel is calculated;

[0102] The total nuclear enthalpy rise is calculated based on the total cooling data and the linear power density of the fuel assemblies of the whole reactor, and the total mass flow rate correction factor is obtained. Based on the core thermal power, thermal-hydraulic parameters, the total nuclear enthalpy rise and the total mass flow rate correction factor and the boiling curve relationship, the deviation from nucleate boiling ratio of the whole reactor is calculated.

[0103] Specifically, the average fuel enrichment refers to the average concentration of fissile materials (such as uranium-235 or plutonium-239) in nuclear fuel. Enrichment is usually expressed as a mass percentage, that is, the ratio of the mass of fissile material to the total mass of fuel. The average fuel enrichment is an important parameter for measuring nuclear fuel performance and reactor operation safety. The mass of fissile material and the total mass of fuel are obtained to calculate the average fuel enrichment.

[0104] The calculation of axial hot spot distribution usually involves multiple steps, including data collection, model building, calculation and iteration, result analysis and display, etc. The following is a simplified calculation process:

[0105] Collect real-time data from various sensors in the reactor (such as thermocouples, detectors, etc.), including temperature, pressure, flow, neutron flux, etc. Build a mathematical model of the reactor core, which usually includes the thermal-hydraulic properties of the fuel rods, the neutron physical properties, and the interactions between them. The model can be a simplified model based on empirical formulas or a more complex numerical model, such as a three-dimensional finite element model, to obtain the full-core power reconstruction coefficient in the core. Input the collected data and the full-core power reconstruction coefficient into the mathematical model to calculate the temperature distribution and coolant density distribution in the core height direction. Since the actual operating conditions may differ from the model assumptions, iterative calculations are required to continuously adjust the model parameters to match the real-time data, obtain the temperature distribution, analyze the temperature distribution, and find the hot spot location and temperature value in the fuel rods.

[0106] The nuclear enthalpy rise factor refers to the ratio of the nuclear enthalpy rise of the coolant when it passes through the core to its specific heat capacity and temperature rise. It is a dimensionless parameter used to characterize the heat exchange efficiency of the coolant and reflects the relationship between the heat exchange efficiency of the coolant when it passes through the core relative to its specific heat capacity and temperature rise.

[0107] The calculation formula of the nuclear enthalpy rise factor (eta) is: eta = H / c_p / T, where: H is the nuclear enthalpy rise, c_p is the specific heat capacity of the coolant (J / kg·K) and T is the temperature rise of the coolant (K).

[0108] Nuclear enthalpy rise refers to the amount of heat absorbed by a unit mass of coolant when it passes through the reactor core. It reflects the heat exchange efficiency of the coolant when it passes through the core. Nuclear enthalpy rise directly represents the increase in heat energy of the coolant when it passes through the core. The calculation formula for nuclear enthalpy rise (H) is: H = Q / m, where: Q is the total heat absorbed by the coolant when it passes through the core. The coolant flow rate is obtained from the operating data of the reactor, and the total heat absorbed by the coolant when it passes through the core is calculated using the channel or full-stack fuel assembly linear power density and the coolant flow path. m is the mass of the coolant (kg), and the nuclear enthalpy rise of each channel or the total nuclear enthalpy rise of the whole stack is obtained.

[0109] Based on the average fuel enrichment, axial hot spot distribution, nuclear enthalpy rise factor, total detector current signal and total power plant operating condition signal, the physical-thermal coupling calculation method is used to obtain the core thermal power; based on the reactor inlet and outlet temperatures, pressurizer pressure and main pump speed, the thermal-hydraulic parameters are calculated; the calculation of core thermal power and thermal-hydraulic parameters are both existing technologies and will not be elaborated here.

[0110] The deviation from nucleate boiling ratio of each channel is calculated based on the core thermal power, thermal-hydraulic parameters, nuclear enthalpy rise and mass flow rate correction factor of each channel and the boiling curve relationship. The deviation from nucleate boiling ratio of the whole reactor is calculated based on the core thermal power, thermal-hydraulic parameters, total nuclear enthalpy rise and total mass flow rate correction factor and the boiling curve relationship. Calculation of the deviation from nucleate boiling ratio is an existing technology and will not be elaborated here.

[0111] In one embodiment, the preset linear power density threshold includes a first linear power density threshold and a second linear power threshold; comparing the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the entire stack, and the preset linear power density threshold, determining and outputting a pre-protection signal and protection information of the linear power density, including:

[0112] Performing a logical OR calculation on the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack to obtain a first calculation result;

[0113] When the first calculation result is greater than or equal to the first line power density threshold and less than the second line power density threshold, a line power density pre-protection signal is output; when the first calculation result is greater than or equal to the second line power density threshold, a line power density protection signal is output.

[0114] Specifically, the linear power density of the fuel assembly of each channel and the linear power density of the entire stack fuel assembly are logically processed to obtain a calculation result, and based on the comparison result between the linear power density protection limit and the calculation result, a pre-protection signal and a protection signal of the linear power density are output.

[0115] Each channel calculates the corresponding fuel assembly linear power density according to a certain method based on a set of detector current values ​​it receives. On the other hand, each channel calculates the linear power density protection limit parameters of the other three channels based on the detector current signal transmitted by another channel, and finally weightedly averages the linear power density protection limit parameters of the four channels into an average value to obtain the protection threshold of the linear power density.

[0116] When the failure rate of core detectors exceeds the limit, the signal processing cabinet fails, the measured rod position signal transmission fails, etc., resulting in the failure of key parameters, the protection threshold of the line power density is adaptively adjusted to ensure that the setting of the protection threshold can keep the core in a safe state.

[0117] In one embodiment, the preset boiling ratio thresholds include a first boiling ratio threshold and a second boiling ratio threshold; comparing the deviation from nucleate boiling ratio of each channel, the deviation from nucleate boiling ratio of the entire stack and the preset boiling ratio thresholds, determining and outputting a pre-protection signal and protection information of the deviation from nucleate boiling ratio, including:

[0118] Performing a logical OR calculation on the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire reactor to obtain a second calculation result;

[0119] When the second calculation result is greater than or equal to the first boiling ratio threshold and less than the second boiling ratio threshold, a pre-protection signal deviating from the nucleate boiling ratio is output; when the second calculation result is greater than or equal to the boiling ratio threshold, a protection signal deviating from the nucleate boiling ratio is output.

[0120] Specifically, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack are logically processed to obtain a calculation result, and based on the comparison result between the boiling ratio protection limit and the calculation result, a pre-protection signal and a protection signal of the boiling ratio are output.

[0121] Each channel calculates the corresponding deviation from the nucleate boiling ratio according to a certain method based on a set of detector current values ​​it receives. On the other hand, each channel calculates the boiling ratio protection limit parameters of the other three channels according to the detector current signal transmitted by another channel, and finally weightedly averages the boiling ratio protection limit parameters of the four channels into an average value to obtain the boiling ratio protection threshold.

[0122] When the failure rate of the core detector exceeds the limit, the signal processing cabinet fails, the measured rod position signal transmission fails, etc., resulting in the failure of key parameters, the protection threshold of the boiling ratio is adaptively adjusted to ensure that the setting of the protection threshold can keep the core in a safe state.

[0123] In one embodiment, before obtaining the rod position information of each control rod in the reactor in the current state, the online protection method of the reactor core further includes:

[0124] Divide the entire reactor into multiple grids in radial and axial directions;

[0125] Obtain the rod position information, detector current signal and power plant operating condition signal corresponding to the control rod in various rod states. Based on the detector current signal and power plant operating condition signal, an online power distribution algorithm is used to obtain the power reconstruction coefficient of each grid in each rod state.

[0126] Based on the rod position information under each rod state and the power reconstruction coefficient of each grid, a preset rod state database is generated.

[0127] Specifically, in a preset rod state, after the whole stack is divided into several grids radially and axially, the fine power peak factor, component power distribution, power conversion coefficient of detector current to component block (calculated by theoretical power distribution and theoretical current), detector theoretical current, hottest rod power factor, etc. of each grid are calculated according to the detector current signal and power plant operating condition signal in the rod state. Based on the fine power peak factor, component power distribution, power conversion coefficient of detector current to component block, detector theoretical current, hottest rod power factor, etc. of each grid, the power reconstruction coefficient of each grid is calculated to obtain the power reconstruction coefficient of the whole stack in the rod state. The upper system regularly calculates the power reconstruction coefficient of the whole stack in each rod state through an online power distribution algorithm based on small grids, and regularly transmits it to the rod state database.

[0128] The full stack power reconstruction coefficients of various preset rod states are obtained by the above method.

[0129] The rod-state database undergoes multiple verifications before being used in lower-level protection calculations: at the upper level, two different redundant algorithms are used to run on different platforms to verify the fine calculation results, it is verified in the fast monitoring calculation link, it is verified in the fast protection calculation link, and it is verified by comparing the fast monitoring calculation with the fast protection calculation, thus ensuring the reliability of the signal calculation used for protection.

[0130] In one embodiment, Figure 5 As shown, it consists of two parts: upper-layer fine calculation and lower-layer fast calculation. The upper-layer system (non-safety level) realizes upper-layer fine calculation, and the lower-layer system (safety level) realizes lower-layer fast calculation, taking into account both the response time and accuracy of the protection channel.

[0131] The upper-level fine calculation mainly performs core physical simulation calculation (including simulator calculation, detector theoretical current calculation, detector layer measured power, detector layer component power distribution, core fuel assembly axial power distribution, core three-dimensional fine power, calculation of LPD and DNBR and other parameters), and uses the simulator to calculate the multi-rod state database according to the preset rod state.

[0132] The cabinet for fast protection calculation in the lower layer is designed to be safe, and a 4-channel method is used to ensure the redundancy of the protection signal. The upper layer fine calculation regularly or irregularly updates the parameters required for the lower layer protection calculation to ensure that the calculation results of the protection signal are consistent with the core status. The upper and lower layers of the system fully interact with each other, and at the same time strictly ensure the isolation requirements of the safe level and the non-safe level.

[0133] The core detectors and control rod core quadrant topology are arranged in the core with regional redundancy. The signal of each protection channel can represent the core status information of the whole reactor, ensuring the redundancy of the protection signal. In the premise of failure of one or two protection channels, the LPD / DNBR protection function can still be executed.

[0134] The reconstructed parameters used for LPD / DNBR protection signal calculation have been subjected to multiple calibration verifications: mutual verification of the two upper-layer sophisticated calculation algorithms / platforms, verification of the upper-layer rapid monitoring calculation, verification of the lower-layer protection calculation, and mutual verification of the upper-layer rapid monitoring calculation and the lower-layer protection calculation have been designed. A quadruple redundant calibration method is used to ensure the reliability and accuracy of the protection signal calculation.

[0135] The system adopts a highly reliable network design: the four cabinets on the lower level exchange information through a redundant ring network, the lower level and the upper level transmit data through a redundant unidirectional network, and the transmission of data such as the upper and lower level downlink reconstruction parameters is achieved through a maintenance network. The downlink maintenance network design ensures full signal interaction and isolation requirements while meeting high-reliability transmission. The entire network architecture ensures highly reliable information transmission while strictly enforcing isolation criteria.

[0136] Furthermore, as a response to the above Figure 1 The embodiment of the present invention provides an online protection device for a reactor core, such as Figure 6 As shown, the device comprises:

[0137] The whole-stack power reconstruction coefficient acquisition module 602 is used to acquire the rod position information of each control rod in the reactor under the current state, and obtain the whole-stack power reconstruction coefficient under the current state according to the rod position information of each control rod and a preset rod state database;

[0138] The fuel assembly linear power density calculation module 604 is used to obtain the detector current signal of the reactor and the power plant operating signal, and calculate the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the full stack power reconstruction coefficient, the detector current signal and the power plant operating signal in the current state;

[0139] The deviation from nucleate boiling ratio calculation module 606 is used to calculate the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack based on the power plant operating condition signal, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack;

[0140] The protection signal determination module 608 is used to compare the linear power density of the fuel assemblies of each channel, the linear power density of the fuel assemblies of the entire stack and a preset linear power density threshold, determine and output the pre-protection signal and protection information of the linear power density, compare the deviation from the nucleate boiling ratio of each channel, the deviation from the nucleate boiling ratio of the entire stack and a preset boiling ratio threshold, determine and output the pre-protection signal and protection information of the deviation from the nucleate boiling ratio.

[0141] The present application provides an online protection device for a reactor core. Compared with the prior art, the device can obtain the rod position information of each control rod in the reactor in the current state in real time, obtain the reactor power reconstruction coefficient in the current state according to the rod position information of each control rod, calculate according to the reactor power reconstruction coefficient in the current state and the measured detector current signal and the power plant operating condition signal, obtain the fuel assembly linear power density of each channel, the fuel assembly linear power density of the whole stack, the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack, realize the protection of the reactor based on the fuel assembly linear power density and the deviation from nucleate boiling ratio, involve the reactor power reconstruction coefficient in the protection parameter calculation, improve the accuracy and reliability of the protection signal, and improve the safety of the power plant.

[0142] In one embodiment, the full stack power reconstruction coefficient acquisition module is further used for:

[0143] According to the rod position information of each control rod, each preset rod state in the preset rod state database is traversed to obtain two preset rod states that are close to the rod position information of the control rod in the current state;

[0144] The power reconstruction coefficients of the two preset rod states are obtained, and the power reconstruction coefficient of the whole stack in the current state is obtained by performing interpolation calculation based on the power reconstruction coefficients of the two preset rod states.

[0145] In one embodiment, the fuel assembly line power density calculation module is further used to:

[0146] Obtain the detector current signal and the power plant operating condition signal corresponding to each channel, and obtain the power reconstruction coefficient corresponding to the node included in each channel from the full stack power reconstruction coefficient;

[0147] Based on the power reconstruction coefficient corresponding to the nodes contained in each channel, the detector current signal corresponding to each channel and the power plant operating condition signal, the linear power density of the fuel assembly of each channel is calculated by the node weighted power calculation method;

[0148] The total detector current signal and the total power plant operating condition signal corresponding to all channels are obtained. Based on the full-stack power reconstruction coefficient, the total detector current signal and the total power plant operating condition signal, the linear power density of the fuel assembly of the whole stack is calculated through the block weighted power calculation method.

[0149] In one embodiment, the deviation from nucleate boiling ratio calculation module is further configured to:

[0150] Obtain fuel data and total cooling data, calculate the average fuel enrichment based on the fuel data, and calculate based on the total cooling data and the linear power density of the fuel assembly of the entire stack to obtain the axial hot spot distribution and the nuclear enthalpy rise factor;

[0151] Based on the average fuel enrichment, axial hot spot distribution, nuclear enthalpy rise factor, total detector current signal and total power plant operating condition signal, the core thermal power is obtained by using the physical-thermal coupling calculation method.

[0152] The reactor inlet and outlet temperatures, the pressurizer pressure and the main pump speed are obtained, and the thermal hydraulic parameters are calculated based on the reactor inlet and outlet temperatures, the pressurizer pressure and the main pump speed;

[0153] The cooling data of each channel is obtained, and the nuclear enthalpy rise of each channel is calculated based on the cooling data of each channel and the linear power density of the fuel assembly, and the mass flow rate correction factor of each channel is obtained. Based on the core thermal power, thermal hydraulic parameters, the nuclear enthalpy rise and mass flow rate correction factor of each channel and the boiling curve relationship, the deviation from nucleate boiling ratio of each channel is calculated;

[0154] The total nuclear enthalpy rise is calculated based on the total cooling data and the linear power density of the fuel assemblies of the whole reactor, and the total mass flow rate correction factor is obtained. Based on the core thermal power, thermal-hydraulic parameters, the total nuclear enthalpy rise and the total mass flow rate correction factor and the boiling curve relationship, the deviation from nucleate boiling ratio of the whole reactor is calculated.

[0155] In one embodiment, the protection signal determination module is further configured to:

[0156] Performing a logical OR calculation on the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack to obtain a first calculation result;

[0157] When the first calculation result is greater than or equal to the first line power density threshold and less than the second line power density threshold, a line power density pre-protection signal is output; when the first calculation result is greater than or equal to the second line power density threshold, a line power density protection signal is output.

[0158] In one embodiment, the protection signal determination module is further configured to:

[0159] Performing a logical OR calculation on the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire reactor to obtain a second calculation result;

[0160] When the second calculation result is greater than or equal to the first boiling ratio threshold and less than the second boiling ratio threshold, a pre-protection signal deviating from the nucleate boiling ratio is output; when the second calculation result is greater than or equal to the boiling ratio threshold, a protection signal deviating from the nucleate boiling ratio is output.

[0161] In one embodiment, the online protection device for the reactor core further comprises:

[0162] The preset rod state database generation module is used to divide the entire reactor into multiple grids from the radial and axial directions; obtain the rod position information, detector current signals and power plant operating condition signals corresponding to the control rods in multiple rod states, and based on the detector current signals and power plant operating condition signals, use an online power distribution algorithm to obtain the power reconstruction coefficient of each grid in each rod state; based on the rod position information in each rod state and the power reconstruction coefficient of each grid, generate a preset rod state database.

[0163] According to one embodiment of the present invention, a storage medium is provided, wherein the storage medium stores at least one executable instruction, and the computer executable instruction can execute the online protection method for the reactor core in any of the above method embodiments.

[0164] According to an embodiment of the present invention, a computer device is provided. The specific embodiment of the present invention does not limit the specific implementation of the computer device.

[0165] The computer device may include: a processor, a communication interface, a memory, and a communication bus.

[0166] Wherein: the processor, the communication interface, and the memory communicate with each other via a communication bus.

[0167] Communication interface, used to communicate with other devices such as client or other server network elements.

[0168] The processor is used to execute the program, and specifically can execute the relevant steps in the above-mentioned embodiment of the online protection method for the reactor core.

[0169] Specifically, the program may include program codes including computer operation instructions.

[0170] The processor may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention. The one or more processors included in the computer device may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0171] The memory is used to store programs. The memory may include a high-speed RAM memory, and may also include a non-volatile memory, such as at least one disk memory.

[0172] The program can be specifically used to enable a processor to execute the online protection method for a reactor core in any of the above method embodiments.

[0173] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices. In one embodiment, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0174] The above embodiments are only exemplary embodiments of the present application and are not intended to limit the present application. The protection scope of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and protection scope of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present application.

Claims

1. A method for online protection of a reactor core, characterized in that: include: Obtaining rod position information of each control rod in the reactor in the current state, and obtaining a full-stack power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database; Acquire the detector current signal and the power plant operating condition signal of the reactor, and calculate the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the full stack power reconstruction coefficient in the current state, the detector current signal and the power plant operating condition signal; Based on the power plant operating condition signal, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack, respectively calculating the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire stack; The linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole stack and a preset linear power density threshold are compared, and a pre-protection signal and protection information of the linear power density are determined and output; the deviation from the nucleate boiling ratio of each channel, the deviation from the nucleate boiling ratio of the whole stack and a preset boiling ratio threshold are compared, and a pre-protection signal and protection information of the deviation from the nucleate boiling ratio are determined and output.

2. The online protection method for a reactor core according to claim 1, characterized in that: The step of obtaining the full stack power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database includes: According to the rod position information of each control rod, traverse each preset rod state in a preset rod state database to obtain two preset rod states that are close to the rod position information of the control rod in the current state; The power reconstruction coefficients of the two preset rod states are obtained, and interpolation calculation is performed based on the power reconstruction coefficients of the two preset rod states to obtain the power reconstruction coefficient of the whole stack in the current state.

3. The online protection method for a reactor core according to claim 1, characterized in that: The step of calculating the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the whole stack power reconstruction coefficient, the detector current signal and the power plant operating condition signal in the current state includes: Obtaining the detector current signal and the power plant operating condition signal corresponding to each channel, and obtaining the power reconstruction coefficient corresponding to the node included in each channel from the full stack power reconstruction coefficient; Based on the power reconstruction coefficient corresponding to the nodes contained in each channel, the detector current signal corresponding to each channel and the power plant operating condition signal, the linear power density of the fuel assembly of each channel is calculated by the node weighted power calculation method; The total detector current signal and the total power plant operating condition signal corresponding to all channels are obtained, and based on the full-stack power reconstruction coefficient, the total detector current signal and the total power plant operating condition signal, the fuel assembly linear power density of the full-stack is calculated through a block weighted power calculation method.

4. The online protection method for a reactor core according to claim 3, characterized in that: The power plant operating condition signal includes: fuel data, cooling data, reactor inlet and outlet temperatures, pressurizer pressure and main pump speed; the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack are calculated based on the power plant operating condition signal, the linear power density of the fuel assembly of each channel and the linear power density of the fuel assembly of the whole stack, respectively, including: Obtaining fuel data and total cooling data, calculating the average fuel enrichment based on the fuel data, and calculating based on the total cooling data and the linear power density of the fuel assembly of the entire stack to obtain the axial hot spot distribution and the nuclear enthalpy rise factor; Based on the average fuel enrichment, the axial hot spot distribution, the nuclear enthalpy rise factor, the total detector current signal and the total power plant operating condition signal, a physical-thermal coupling calculation method is used to obtain the core thermal power; Acquire reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed, and calculate thermal hydraulic parameters based on the reactor inlet and outlet temperatures, pressurizer pressure, and main pump speed; Acquire cooling data of each channel, calculate based on the cooling data of each channel and the linear power density of the fuel assembly to obtain the nuclear enthalpy rise of each channel, obtain the mass flow rate correction factor of each channel, and calculate the deviation from nucleate boiling ratio of each channel based on the core thermal power, thermal hydraulic parameters, the nuclear enthalpy rise and mass flow rate correction factor of each channel and the boiling curve relationship; The total nuclear enthalpy rise is calculated based on the total cooling data and the linear power density of the fuel assembly of the whole stack, and the total mass flow rate correction factor is obtained. The deviation from nucleate boiling ratio of the whole stack is calculated based on the core thermal power, thermal-hydraulic parameters, the total nuclear enthalpy rise and the total mass flow rate correction factor and the boiling curve relationship.

5. The online protection method for a reactor core according to claim 1, characterized in that: The preset linear power density threshold comprises a first linear power density threshold and a second linear power threshold; the comparing the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole stack and the preset linear power density threshold, determining and outputting the pre-protection signal and protection information of the linear power density comprises: Performing a logical OR calculation on the fuel assembly linear power density of each channel and the fuel assembly linear power density of the entire stack to obtain a first calculation result; When the first calculation result is greater than or equal to the first line power density threshold and less than the second line power density threshold, a line power density pre-protection signal is output; when the first calculation result is greater than or equal to the second line power density threshold, a line power density protection signal is output.

6. The online protection method for a reactor core according to claim 1, characterized in that: The preset boiling ratio threshold includes a first boiling ratio threshold and a second boiling ratio threshold; the comparison of the deviation from nucleate boiling ratio of each channel, the deviation from nucleate boiling ratio of the whole stack and the preset boiling ratio threshold, determining and outputting the pre-protection signal and protection information of the deviation from nucleate boiling ratio, includes: Performing a logical OR calculation on the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the entire reactor to obtain a second calculation result; When the second calculation result is greater than or equal to the first boiling ratio threshold and less than the second boiling ratio threshold, a pre-protection signal deviating from the nucleate boiling ratio is output; when the second calculation result is greater than or equal to the boiling ratio threshold, a protection signal deviating from the nucleate boiling ratio is output.

7. The online protection method for a reactor core according to any one of claims 1 to 6, characterized in that: Before obtaining the rod position information of each control rod in the reactor in the current state, the online protection method of the reactor core further includes: Divide the entire reactor into multiple grids in radial and axial directions; Obtaining rod position information, detector current signals, and power plant operating condition signals corresponding to control rods in multiple rod states, and obtaining a power reconstruction coefficient of each grid in each rod state by using an online power distribution algorithm based on the detector current signals and the power plant operating condition signals; Based on the rod position information under each rod state and the power reconstruction coefficient of each grid, a preset rod state database is generated.

8. An online protection device for a reactor core, characterized in that: include: A full-stack power reconstruction coefficient acquisition module is used to obtain the rod position information of each control rod in the reactor in the current state, and obtain the full-stack power reconstruction coefficient in the current state according to the rod position information of each control rod and a preset rod state database; A fuel assembly linear power density calculation module is used to obtain the detector current signal of the reactor and the power plant operating signal, and calculate the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack based on the full stack power reconstruction coefficient in the current state, the detector current signal and the power plant operating signal; a deviation from nucleate boiling ratio calculation module, for calculating the deviation from nucleate boiling ratio of each channel and the deviation from nucleate boiling ratio of the whole stack respectively based on the power plant operating condition signal, the fuel assembly linear power density of each channel and the fuel assembly linear power density of the whole stack; The protection signal determination module is used to compare the linear power density of the fuel assembly of each channel, the linear power density of the fuel assembly of the whole stack and a preset linear power density threshold, determine and output a pre-protection signal and protection information of the linear power density, compare the deviation from the nucleate boiling ratio of each channel, the deviation from the nucleate boiling ratio of the whole stack and a preset boiling ratio threshold, determine and output a pre-protection signal and protection information of the deviation from the nucleate boiling ratio.

9. A storage medium storing at least one executable instruction, wherein the executable instruction enables a processor to execute the operation of the online protection method for a reactor core as described in any one of claims 1 to 7.

10. A computer device comprising: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform operations corresponding to the online protection method for a reactor core according to any one of claims 1-7.

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