High temperature gas cooled reactor unit nuclear-thermal-electric coupling modeling simulation method

Abstract

The application provides a high-temperature gas cooled reactor unit nuclear-thermal-electric coupling modeling simulation method, relates to the network-involved dynamic simulation technical field of a nuclear power unit, and comprises the following steps: dividing a high-temperature gas cooled reactor unit into multiple main dynamic modules, and determining equivalent non-main details in a nuclear-thermal-electric coupling process of the high-temperature gas cooled reactor unit; regarding the equivalent non-main details as modeling granularity constraints, respectively performing simulation modeling on each main dynamic module, constructing a simulation model corresponding to each main dynamic module, and forming a sub-model set of the high-temperature gas cooled reactor unit model; regarding standardized interface variables of nuclear-thermal-electric as a link, circularly connecting each sub-model of the high-temperature gas cooled reactor unit model according to a forward energy transmission link and a reverse control feedback link of the high-temperature gas cooled reactor unit, and forming a nuclear-thermal-electric coupling integrated simulation model of the high-temperature gas cooled reactor unit. The application can construct the nuclear-thermal-electric coupling integrated simulation model of the high-temperature gas cooled reactor unit through the above scheme.

Description

Technical Field

[0001] This application relates to the field of dynamic simulation technology for nuclear power units connected to the grid, and in particular to a nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units. Background Technology

[0002] High-temperature gas-cooled reactor nuclear power units use helium as the primary cooling medium, and are characterized by large core heat capacity, strong thermal inertia, and a long coupling chain between nuclear thermal processes and power generation processes. During grid-connected operation, the core neutron dynamics, primary helium thermal processes, steam generator heat exchange processes, secondary loop pressure and temperature processes, turbine speed regulation processes, generator electromagnetic transient processes, and excitation control processes interact with each other, forming a coupled dynamic between the nuclear side, thermal side, mechanical side, and electrical side.

[0003] In existing power system simulation models, nuclear power units are often simplified to conventional steam turbine generator sets, and the reactor and primary loop processes are typically represented as fixed heat sources, power input signals, or simple inertial elements. While these models can be used for some electrical transient analysis, they struggle to reflect the dynamic relationships unique to high-temperature gas-cooled reactors, including neutron power, helium flow rate, hot helium temperature, cold helium temperature, core temperature, reflector temperature, main steam pressure, turbine mechanical power, and generator electromagnetic power. The simulated dynamic response deviates significantly from actual unit operating conditions, resulting in poor simulation performance. This hinders the optimization of unit operating control parameters and makes it difficult to improve unit operating stability and overall power generation efficiency. Summary of the Invention

[0004] In view of this, this application proposes a nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units.

[0005] Firstly, this application provides a nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units, including: Based on the principle of module selection, the high-temperature gas-cooled reactor unit is divided into multiple dominant dynamic modules, and the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit are determined. Using the equivalent non-dominant details as modeling granularity constraints, simulation modeling is performed separately for each dominant dynamic module, and simulation models corresponding to each dominant dynamic module are constructed to form a set of sub-models for the high-temperature gas-cooled reactor unit model. Using the standardized interface variables of nuclear-thermal-electricity as a link, the sub-models of the high-temperature gas-cooled reactor unit model are connected in a closed loop according to the forward energy transfer link and the reverse control feedback link of the high-temperature gas-cooled reactor unit, forming an integrated simulation model of nuclear-thermal-electricity coupling of the high-temperature gas-cooled reactor unit.

[0006] In one embodiment, the high-temperature gas-cooled reactor unit is divided into multiple dominant dynamic modules based on the module selection principle, and the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit are determined, including: Based on the dominant roles of the dynamic processes on the nuclear side, thermal side, mechanical side, and electric side of the high-temperature gas-cooled reactor unit, the high-temperature gas-cooled reactor unit is divided into a nuclear side module, a thermal side module, a mechanical side module, and an electric side module. The nuclear side module includes a reactor power control module and a core neutron dynamics module. The thermal side module includes a primary loop helium thermal temperature module and a steam generator and secondary loop module. The mechanical side module includes a grid-connected speed control system module, a main steam valve actuator module, a bypass system module, and a turbine module. The electric side module includes a synchronous generator and grid module, an excitation system, and a power system stabilizer module. The core three-dimensional power distribution, local flow channel heat transfer details, detailed valve hydraulic servo process, and actual power grid detailed grid structure are simplified by equivalent means to determine the corresponding equivalent point reactor dynamics, lumped heat capacity nodes, actuator functions, and equivalent power grid boundaries.

[0007] In one embodiment, the step of using the equivalent non-dominant details as modeling granularity constraints, performing simulation modeling for each dominant dynamic module separately, and constructing a simulation model corresponding to each dominant dynamic module includes: Based on the particle size constraints of the aforementioned point-pile dynamics, a core-side simulation model of a high-temperature gas-cooled reactor unit is constructed. Based on the granularity constraints of the lumped heat capacity nodes, a hot-side simulation model of a high-temperature gas-cooled reactor unit is constructed. Based on the granularity constraints of the actuator function, a mechanical-side simulation model of the high-temperature gas-cooled reactor unit is constructed. Based on the granularity constraints of the equivalent power grid boundary, an electric-side simulation model of a high-temperature gas-cooled reactor unit is constructed.

[0008] In one embodiment, constructing a core-side simulation model of a high-temperature gas-cooled reactor unit based on the granularity constraints of the point reactor dynamics includes: Using the relative neutron power, characterized by lumped characteristics under point reactor dynamics constraints, as the control object, the deviation between the given relative neutron power and the actual relative neutron power is taken as the input. The input is used to perform proportional-integral calculation to generate the initial external reactivity. The external reactivity output by setting the amplitude limit constraint on the initial external reactivity is taken as the output to construct a reactor power control sub-model. Following the granular simplification rules of point reactor dynamics, the main body of the model is constructed using six sets of delayed neutron point reactor dynamics equations. The total reactivity obtained by superimposing the external reactivity and the temperature feedback reactivity is used as the driving input of the core neutron dynamics sub-model, and the relative neutron power is used as the output to construct the core neutron dynamics sub-model. The temperature feedback reactivity is jointly determined by the core temperature deviation and the reflector temperature deviation.

[0009] In one embodiment, constructing a hot-side simulation model of a high-temperature gas-cooled reactor unit based on the granularity constraints of the lumped heat capacity nodes includes: The core structure, reflector, and primary loop helium are respectively represented as lumped heat capacity nodes. The core thermal power is used as the driving input to establish the thermal balance differential equations of each node to construct the main body of the model. The core temperature, reflector temperature and primary loop hot helium outlet temperature are used as the outputs to construct the primary loop helium thermal temperature sub-model. The heat exchange metal wall and the secondary loop steam-water working fluid are equivalent to lumped heat capacity nodes. The primary loop hot helium outlet temperature is used as the driving input. The dynamic calculation relationship is established in the form of deviation equations to construct the main body of the model. The main steam pressure and main steam temperature state variables are used as outputs to construct the steam generator and secondary loop sub-model.

[0010] In one embodiment, constructing the mechanical-side simulation model of the high-temperature gas-cooled reactor unit based on the granularity constraints of the actuator function includes: Using the unit speed deviation and power deviation as inputs, and the main steam valve opening given signal generated by the speed control law as output, a sub-model of the grid-connected speed control system is constructed. Following the granular simplification rules of the actuator function, ignoring the fine process of hydraulic servo inside the valve, the main body of the model is constructed using the given signal of the main steam valve opening as input and a first-order inertial actuator function containing opening limit and rate of change limit. The main steam valve actuator sub-model is constructed using the actual main steam valve opening as output. Following the granular simplification rules of the actuator function, ignoring the fine process of hydraulic servo inside the valve, the main steam pressure deviation is used as input, and the bypass opening given signal is generated through bypass control logic. The main body of the model is constructed using a first-order inertial actuator function that includes opening limit and rate of change limit, and the bypass system sub-model is constructed using the actual bypass opening as output. Using the main steam pressure, actual main steam valve opening, and actual bypass opening as inputs, the main model is constructed by establishing power calculation relationships based on steam flow characteristics, and the turbine sub-model is constructed by using the unit mechanical power as output.

[0011] In one embodiment, constructing the electric-side simulation model of the high-temperature gas-cooled reactor unit based on the granularity constraints of the equivalent power grid boundary includes: Following the granular simplification rules of the equivalent power grid boundary, the external power grid is equivalent to an infinite power grid and an equivalent impedance boundary. The main body of the model is constructed based on the electromechanical transient equations of the synchronous generator, with the unit terminal electrical quantities and rotor operating parameters as inputs. The active power, reactive power, and terminal voltage of the unit are used as outputs to construct the synchronous generator and power grid sub-models. Using the unit speed deviation, terminal voltage deviation and power fluctuation as inputs, the excitation regulation given signal is generated through the power system stabilizer damping regulation logic and excitation control law calculation. The main body of the model is constructed based on the dynamic response equation of the excitation system, and the excitation system and power system stabilizer sub-models are constructed with the actual excitation voltage and excitation current as outputs.

[0012] In one embodiment, the nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units further includes: The integrated simulation model of nuclear-thermal-electric coupling is simulated and verified under various preset working conditions, and simulation verification results are generated.

[0013] In one embodiment, the preset operating conditions include zero-disturbance steady-state holding condition, power increase step condition, power decrease step condition, inlet helium temperature disturbance condition, thermal power and mechanical power coordinated disturbance condition, speed regulation small disturbance condition, power system stabilizer switching comparison condition, and complete coupled model and fixed heat source boundary model comparison condition.

[0014] Secondly, this application also provides a nuclear-thermal-electric coupling modeling and simulation system for high-temperature gas-cooled reactor units, including: The module division is used to divide the high-temperature gas-cooled reactor unit into multiple dominant dynamic modules based on the module selection principle, and to determine the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit. The first modeling module is used to take the equivalent non-dominant details as modeling granularity constraints, perform simulation modeling for each dominant dynamic module, construct simulation models corresponding to each dominant dynamic module, and form a set of sub-models for the high-temperature gas-cooled reactor unit model. The second modeling module is used to connect the sub-models of the high-temperature gas-cooled reactor unit model in a closed loop according to the forward energy transfer link and the reverse control feedback link of the high-temperature gas-cooled reactor unit, using the nuclear-thermal-electric standardized interface variables as the link, to form an integrated simulation model of the nuclear-thermal-electric coupling of the high-temperature gas-cooled reactor unit.

[0015] The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units proposed in this application has the following advantages over related technologies: 1. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units proposed in this application divides the dominant dynamic modules of the high-temperature gas-cooled reactor unit based on the principle of module selection and clarifies the equivalent non-dominant details. The equivalent non-dominant details are used as modeling granularity constraints to simulate and model each dominant dynamic module separately, forming a set of sub-models. This approach not only fully preserves the physical characteristics of core dynamic processes such as neutron dynamics, primary loop helium thermal engineering, secondary loop heat transfer, and electromechanical transients, but also accurately characterizes the dynamic changes of key parameters such as neutron power, helium temperature, core and reflector temperatures, and main steam pressure. Furthermore, by reasonably simplifying the non-dominant details through granular constraints, it avoids the problem of excessive computation caused by fully detailed modeling, thus balancing simulation fidelity and computational efficiency.

[0016] 2. By using standardized interface variables for nuclear-thermal-electricity as a link, each sub-model is connected in a closed loop along the forward energy transfer link and the reverse control feedback link, thus constructing a nuclear-thermal-electricity coupled integrated simulation model. This model opens up the entire energy transfer path from nuclear fission energy release to primary loop heat exchange, secondary loop steam work, and generator grid connection. It also covers reverse interaction mechanisms such as temperature reactive feedback and power closed-loop regulation, fully reproducing the dynamic coupling relationship between neutron power, thermal parameters, turbine mechanical power, and generator electromagnetic power. This effectively solves the problem that existing simplified models cannot reflect the dynamic interaction characteristics of multiple physics fields in high-temperature gas-cooled reactors. It can support more comprehensive system dynamic characteristic analysis and control strategy verification, which is conducive to the optimization of unit operation control parameters, thereby improving unit operation stability and overall power generation efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating the nuclear-thermal-electric coupling modeling and simulation method for a high-temperature gas-cooled reactor unit in one embodiment of this application. Figure 2 This is a schematic diagram of the integrated nuclear-thermal-electric coupling topology and module selection of a high-temperature gas-cooled reactor unit in one embodiment of this application; Figure 3 This is a diagram of the nuclear thermal closed-loop coupling structure of the reactor body in one embodiment of this application; Figure 4 This is a structural diagram of the calculation of neutron dynamics and reactivity in the reactor core according to one embodiment of this application; Figure 5This is a simplified boundary structure diagram of the heat power transfer of a primary loop helium-steam generator in one embodiment of this application; Figure 6 This is a diagram illustrating the coupling structure of the main steam valve / bypass—grid-connected speed regulation—steam turbine—generator—excitation system in one embodiment of this application. Figure 7 This is a comparison of the operating condition response curves of the fully coupled model and the fixed heat source boundary model in one embodiment of this application; Figure 8 This is a diagram showing the response curves of the main state variables under the zero-disturbance steady-state holding condition in one embodiment of this application. Figure 9 This is a diagram showing the coordinated response curves of the nuclear thermal side and the electromechanical side under the power step-up condition in one embodiment of this application. Figure 10 This is a diagram showing the response curves of the main state variables under the power reduction step condition in one embodiment of this application. Figure 11 This is a temperature feedback response curve under inlet helium temperature disturbance conditions in one embodiment of this application; Figure 12 This is a diagram showing the valve and electromechanical power response curves under small speed disturbance conditions in one embodiment of this application. Figure 13 This is a diagram showing the electrical side response curves under the power system stabilizer switching comparison condition in one embodiment of this application. Figure 14 This is a schematic diagram of the structure of the nuclear-thermal-electric coupling modeling and simulation system for a high-temperature gas-cooled reactor unit in one embodiment of this application. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] In some embodiments, such as Figure 1 As shown, the present application provides a nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units, which includes the following steps S101 to S103.

[0021] S101: Based on the principle of module selection, the high-temperature gas-cooled reactor unit is divided into multiple dominant dynamic modules, and the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit are determined.

[0022] Among them, such as Figure 2As shown, the module selection principles are as follows: the core side retains reactive feedback and six sets of delayed neutron point reactor dynamics, with equivalent core space power distribution; the thermal side retains main helium flow rate, hot helium temperature, cold helium temperature, main steam pressure and intermediate heat capacity temperature, with equivalent local flow channels and three-dimensional heat transfer details; the mechanical side retains the main steam valve, intermediate steam valve, bypass, OPC (overspeed protection signal) and turbine power transmission relationship, with equivalent detailed hydraulic servo and valve internal structure; the electrical side retains the main dynamics of synchronous generator, equivalent grid, excitation system and power system stabilizer, with equivalent detailed actual grid structure.

[0023] Understandably, guided by the core requirements of unit system-level dynamic simulation, and based on the weight of each physical process's impact on the overall dynamic characteristics of the unit, differences in time scale, and the hierarchical role in the energy transfer chain, the core physical processes that determine the unit's macroscopic dynamic response are divided into independent dominant dynamic modules. These include the nuclear-side dynamic module carrying neutron fission energy release and power regulation, the thermal-side dynamic module carrying helium heat exchange and steam generation, the mechanical-side dynamic module carrying steam flow and power conversion, and the electrical-side dynamic module carrying electromechanical energy conversion and grid connection interaction. Simultaneously, details with low impact on the overall dynamic characteristics of the system, strong locality, and significant differences in time scale from the dominant processes are selected as equivalent non-dominant details. These include differences in the three-dimensional power distribution of the reactor core, the uneven heat transfer characteristics of the primary loop's local flow channels, the fine-grained motion processes of hydraulic servos within valves, and the complex branch topology of the external power grid. This clarifies the simplification boundaries and granularity benchmarks for modeling.

[0024] S102: Using equivalent non-dominant details as modeling granularity constraints, simulation modeling is performed separately for each dominant dynamic module, and simulation models corresponding to each dominant dynamic module are constructed to form a set of sub-models for the high-temperature gas-cooled reactor unit model.

[0025] It is understandable that by using the equivalent non-dominant details identified in the previous screening as the simplified boundaries and accuracy benchmarks for modeling each module, each sub-model fully retains the physical essence and core characteristics of the dominant dynamic process under the corresponding granularity constraints, while eliminating local details that have a negligible impact on the overall dynamic simulation of the system. Ultimately, they together constitute a set of high-temperature gas-cooled reactor unit sub-models with clear hierarchy, well-defined boundaries, and appropriate granularity, providing standardized independent model units for subsequent nuclear-thermal-electric full-link coupling integration.

[0026] S103: Using the nuclear-thermal-electric standardized interface variables as a link, the sub-models of the high-temperature gas-cooled reactor unit model are connected in a closed loop according to the forward energy transfer link and the reverse control feedback link of the high-temperature gas-cooled reactor unit, forming an integrated simulation model of nuclear-thermal-electric coupling of the high-temperature gas-cooled reactor unit.

[0027] In the application, a standardized set of interactive physical quantities between each sub-model is predefined as standardized interface variables. Then, the energy transfer sub-models of the core side, thermal side, mechanical side, and electrical side are sequentially connected along the forward energy transfer link. The core relative neutron power is used as the energy input interface for energy transfer from the core side to the thermal side. The core temperature and reflector temperature are used as the thermal interface for feedback from the thermal side to the core side. The primary loop hot helium outlet temperature is used as the heat exchange interface for heat transfer from the primary loop side to the steam generator side. The main steam pressure and main steam temperature are used as the steam parameter interface for heat transfer from the thermal side to the mechanical side. The unit mechanical power is used as the power input interface for power transfer from the mechanical side to the electrical side. This fully establishes the forward energy flow transfer path from nuclear fission energy release, helium heat transfer, steam work drive to electromechanical energy conversion.

[0028] Simultaneously, the various control and regulation sub-models and energy transfer sub-models are connected along the reverse control feedback link. Speed ​​deviation and power deviation signals are input to the grid-connected speed regulation and reactor power control links, valve opening signals are output to the turbine flow calculation link, excitation regulation signals are output to the synchronous generator electrical calculation link, and core and reflector temperature signals are fed back to the neutron dynamics reactivity calculation link, forming a reverse control closed loop covering power closed-loop regulation, temperature reactivity feedback, and grid-connected coordinated control. Standardized interface variables ensure consistency and standardization of data interaction between sub-models. Based on the bidirectional closed-loop connection of the forward energy link and the reverse feedback link, the dispersed sub-models are integrated into a physically logically complete and logically interconnected nuclear-thermal-electric multiphysics integrated simulation model, fully reproducing the dynamic coupling and interaction characteristics of the entire high-temperature gas-cooled reactor unit system.

[0029] The aforementioned nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units divides the unit into dominant dynamic modules based on the principle of module selection and clarifies equivalent non-dominant details. These equivalent non-dominant details are then used as modeling granularity constraints to simulate and model each dominant dynamic module separately, forming a set of sub-models. This approach fully preserves the physical characteristics of core dynamic processes such as neutron dynamics, primary loop helium thermal processes, secondary loop heat transfer, and electromechanical transients, accurately depicting the dynamic changes of key parameters such as neutron power, helium temperature, core and reflector temperatures, and main steam pressure. Furthermore, by reasonably simplifying non-dominant details through granular constraints, it avoids the excessive computational burden caused by fully detailed modeling, thus balancing simulation fidelity and computational efficiency. By using standardized interface variables for nuclear-thermal-electricity as a link, the sub-models are connected in a closed loop along the forward energy transfer link and the reverse control feedback link to construct an integrated simulation model of nuclear-thermal-electricity coupling. This model opens up the entire energy transfer path from nuclear fission energy release to primary loop heat exchange, secondary loop steam work, and generator grid connection. It also covers reverse interaction mechanisms such as temperature reactive feedback and power closed-loop regulation, and fully reproduces the dynamic coupling relationship between neutron power, thermal parameters, turbine mechanical power, and generator electromagnetic power. This effectively solves the problem that existing simplified models cannot reflect the dynamic interaction characteristics of multi-physics fields in high-temperature gas-cooled reactors. It can support more comprehensive system dynamic characteristic analysis and control strategy verification, which is conducive to the optimization of unit operation control parameters, thereby improving unit operation stability and overall power generation efficiency.

[0030] In some embodiments, the high-temperature gas-cooled reactor unit is divided into multiple dominant dynamic modules based on the module selection principle, and the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit are determined. This includes: dividing the high-temperature gas-cooled reactor unit into a nuclear-side module, a thermal-side module, a mechanical-side module, and an electric-side module according to the dominant role of the dynamic processes on the nuclear side, thermal side, mechanical side, and electric side of the high-temperature gas-cooled reactor unit; and performing equivalent simplification on the three-dimensional power distribution of the reactor core, local flow channel heat transfer details, detailed valve hydraulic servo processes, and actual grid detailed network structure to determine the corresponding equivalent point reactor dynamics, lumped heat capacity nodes, actuator functions, and equivalent grid boundaries.

[0031] The nuclear-side modules include a reactor power control module and a core neutron dynamics module; the thermal-side modules include a primary loop helium thermal temperature module and a steam generator and secondary loop module; the mechanical-side modules include a grid-connected speed control system module, a main steam valve actuator module, a bypass system module, and a turbine module; and the electrical-side modules include a synchronous generator and grid module, an excitation system, and a power system stabilizer module. The reactor power control module outputs external reactivity; the core neutron dynamics module outputs relative neutron power; the primary loop helium thermal temperature module outputs hot helium temperature, cold helium temperature, core temperature, and reflector temperature; the steam generator and secondary loop module outputs main steam pressure and steam flow rate; the grid-connected speed control system and valve bypass module outputs valve control signals and bypass steam flow rate; the turbine module outputs mechanical power; the synchronous generator and grid module outputs electromagnetic power, rotor angular velocity, and terminal voltage signals; and the excitation system and power system stabilizer module outputs excitation voltage and stabilization auxiliary signals.

[0032] Based on the principle of module selection, and considering the complete energy transfer chain of a high-temperature gas-cooled reactor unit—including nuclear fission energy release, helium heat transfer, steam power generation, and electromechanical energy conversion—the multi-physics coupled system can be divided into four main dynamic modules according to the influence weight and functional attributes of each physical process on the overall dynamic characteristics of the system. The nuclear-side module corresponds to the core processes of neutron dynamics and power regulation, further subdivided into the reactor power control module responsible for closed-loop power regulation and the core neutron dynamics module responsible for the dynamic characteristics of core neutron fission. The thermal-side module corresponds to the core processes of heat transfer and steam generation, further subdivided into the primary loop helium thermal temperature module for core heat removal and temperature feedback, and the steam generator and secondary loop module for primary and secondary heat exchange and steam parameter regulation. The mechanical-side module corresponds to the core processes of steam flow and mechanical power output, further subdivided into the module responsible for grid connection frequency and... The system comprises a power regulation module for grid-connected speed control, a main steam valve actuator module for regulating the main steam valve opening, a bypass system module for releasing excess steam, and a turbine module for converting steam thermal energy into mechanical work. The electric side module corresponds to the core process of electromechanical energy conversion and grid interaction, and is further subdivided into a synchronous generator and grid module that carries the interaction between the synchronous generator's electromechanical transient characteristics and the grid boundary, and an excitation system and power system stabilizer module that undertakes terminal voltage regulation and system damping support, forming a modular architecture with clear functional boundaries and well-defined hierarchical divisions.

[0033] Based on this, non-dominant details within each module that have a low impact on the overall dynamic response of the system, strong locality, and significant differences in time scale from the dominant process are simplified by equivalent processing. Specifically, this includes lumped equivalence of the differences in three-dimensional power distribution in the core on the nuclear side, homogenization of the fine heat transfer non-uniformity characteristics of the local flow channels on the thermal side, functionalization of the detailed hydraulic servo action process inside the valves on the mechanical side, and equivalence of the detailed grid topology and branch parameters of the actual power grid on the electric side. This leads to the determination of four types of modeling granularity constraints: point reactor dynamics, lumped heat capacity nodes, actuator functions, and equivalent power grid boundaries. This provides a clear simplified boundary and accuracy control basis for the subsequent granular simulation modeling of each module.

[0034] In some embodiments, equivalent non-dominant details are used as modeling granularity constraints, and simulation modeling is performed separately for each dominant dynamic module to construct a simulation model corresponding to each dominant dynamic module. This includes the following steps: constructing a core-side simulation model of the high-temperature gas-cooled reactor unit based on granular constraints of point reactor dynamics; constructing a thermal-side simulation model of the high-temperature gas-cooled reactor unit based on granular constraints of lumped heat capacity nodes; constructing a mechanical-side simulation model of the high-temperature gas-cooled reactor unit based on granular constraints of actuator functions; and constructing an electrical-side simulation model of the high-temperature gas-cooled reactor unit based on granular constraints of equivalent grid boundaries.

[0035] It is understandable that, for the core-side module, point-pile dynamics is used as the granular constraint, the neutron fission process in the core is lumped parameterized, the local differences in the three-dimensional power distribution are ignored, and a simulation model is built around the core physical relationship of neutron density, reactivity and temperature feedback, so as to accurately reproduce the overall characteristics of the core power dynamic response.

[0036] For the hot-side module, the lumped heat capacity node is used as the granular constraint. The thermal processes such as primary loop heat exchange and steam generator heat exchange are equivalent to homogenized lumped heat capacity units. The uneven heat exchange in local flow channels and the local differences caused by fine structure are ignored. Based on the relationship between energy conservation and thermal balance, a simulation model is constructed to fully characterize the macroscopic dynamic law of heat transfer and steam parameter changes.

[0037] For the mechanical side module, the actuator function is used as the granular constraint. The dynamic characteristics of actuators such as valve regulation are equivalent to a standardized transfer function model. The fine motion process of internal hydraulic servo and mechanical transmission is ignored. The simulation model is built around the core logic of steam flow and power conversion, which effectively characterizes the dominant response characteristics of valve opening regulation and mechanical power output.

[0038] For the electrical side modules, the equivalent grid boundary is used as the granular constraint. The external grid-connected grid is equivalent to a simplified equivalent boundary model, ignoring the detailed network topology and branch parameter differences of the actual grid. A simulation model is constructed around the core mechanism of synchronous generator electro-electrical energy conversion and grid-connected interaction, accurately reflecting the coupling dynamic characteristics of the unit's electrical output and the grid boundary. By using equivalent non-dominant details as modeling granular constraints, simulation modeling is performed separately for each dominant dynamic module. Ultimately, a domain-specific simulation model system with clear module boundaries, adaptable granularity, and complete core physical characteristics can be formed, reasonably controlling model complexity while ensuring simulation accuracy.

[0039] In some embodiments, a core-side simulation model of a high-temperature gas-cooled reactor unit is constructed based on the granular constraints of point reactor dynamics. This includes: using the relative neutron power, lumped in character under point reactor dynamics constraints, as the control object; taking the deviation between the given relative neutron power and the actual relative neutron power as input; performing proportional-integral calculations on the input to generate initial external reactivity; and using the external reactivity output by setting a limiting constraint on the initial external reactivity as the output to construct a reactor power control sub-model; following the granular simplification rules of point reactor dynamics, using six sets of delayed neutron point reactor dynamics equations to construct the main body of the model; using the total reactivity obtained by superimposing the external reactivity and the temperature feedback reactivity as the driving input of the core neutron dynamics sub-model; and using the relative neutron power as the output to construct the core neutron dynamics sub-model. The temperature feedback reactivity is jointly determined by the core temperature deviation and the reflector temperature deviation.

[0040] In application, the applied reactivity is generated by the reactor power control system based on the deviation between the given relative neutron power and the actual relative neutron power, and a limiting constraint is applied to the applied reactivity. The formula corresponding to the reactor power control sub-model is:

[0041] in, This is the relative neutron power deviation signal. Given a relative neutron power value, This represents the actual relative neutron power. For added reactivity, and These are the proportional and integral coefficients for reactor power control, respectively. This is the external reactive limit value.

[0042] The core neutron dynamics sub-model is established using six sets of delayed neutron point reactor dynamics equations, the expressions of which are as follows: in, Relative neutron power, For total reactivity, For the total delayed neutron share, The neutron generation time constant, Let i be the concentration of the delayed neutron precursor nuclei in the i-th group. Let be the decay constant of the i-th group of delayed neutron precursor nuclei. Let be the share of the i-th delayed neutron emission group.

[0043] The total reactivity is obtained by superimposing the externally applied reactivity and the temperature feedback reactivity. The temperature feedback reactivity is determined by both the core temperature deviation and the reflector temperature deviation. The corresponding formula is as follows:

[0044] in, For added reactivity, For temperature feedback responsiveness, Core temperature, Temperature of the reflective layer and These are the corresponding initial temperature values. and These are the core temperature reactivity coefficient and the reflector temperature reactivity coefficient, respectively.

[0045] It should be noted that, as Figure 3 As shown, the reactor's nuclear thermal closed loop consists of a core neutron dynamics sub-model and a primary loop helium thermal operating temperature sub-model. Relative neutron power acts on the primary loop helium thermal operating temperature sub-model, causing changes in hot helium temperature, cold helium temperature, core temperature, and reflector temperature; the core temperature and reflector temperature are fed back to the core neutron dynamics sub-model, participating in temperature feedback reactivity calculations. For example... Figure 4 As shown, the core neutron dynamics and reactivity calculation structure includes power deviation calculation, reactor power control, temperature feedback reactivity calculation, total reactivity superposition, and six sets of delayed neutron point reactor dynamics calculations. Through this structure, the model can simultaneously reflect the effects of applied reactivity control and temperature feedback reactivity.

[0046] In some embodiments, a thermal-side simulation model of a high-temperature gas-cooled reactor unit is constructed based on the granularity constraints of lumped heat capacity nodes. This includes: equating the core structure, reflector layer, and primary loop helium gas to lumped heat capacity nodes, establishing thermal balance differential equations for each node as the driving input to construct the main body of the model, and constructing a primary loop helium gas thermal temperature sub-model with core temperature, reflector layer temperature, and primary loop hot helium outlet temperature as outputs; equating the heat exchange metal wall and secondary loop steam-water working fluid to lumped heat capacity nodes, establishing dynamic calculation relationships using deviation equations as the driving input to construct the main body of the model, and constructing a steam generator and secondary loop sub-model with main steam pressure and main steam temperature state variables as outputs.

[0047] The primary loop helium thermal temperature sub-model includes a dynamic component for the main helium flow rate. This component calculates the actual main helium flow rate based on a given value or a normalized value for the main helium blower frequency. The corresponding formula is as follows:

[0048] in, The time constant of the main helium flow dynamic link. This represents the actual main helium flow rate. The setpoint for the main helium flow rate. The frequency normalization quantity of the main helium blower.

[0049] In the primary loop helium thermal temperature sub-model, the core heat output is proportional to the relative neutron power, while the helium heat absorption power is related to the main helium flow rate, the temperature difference between hot and cold helium, and the core heat output matches the helium heat absorption power at steady state. The corresponding formulas are as follows:

[0050] in, To release thermal power to the reactor core, To release the rated core heat power, Relative neutron power, The heat absorption power of helium gas. Main helium flow rate, The specific heat capacity of helium at constant pressure. The temperature of hot helium. This is the temperature of cold helium.

[0051] The hot helium temperature is established by coupling the power to the main helium flow rate ratio. The reference value for the hot helium temperature is the sum of the inlet helium temperature and the rated temperature rise multiplied by the ratio of the relative neutron power to the main helium flow rate, and is output through a first-order inertial element. in, This is a reference value for the temperature of hot helium. For the inlet helium temperature, For rated temperature rise, Relative neutron power, The lower limit for calculating the main helium flow rate. is the time constant of the first-order inertial element at the thermal helium temperature.

[0052] like Figure 5 As shown, the heat power transfer and simplified boundary structure of the primary loop helium-steam generator include the core heat source, main helium flow dynamics, primary loop helium thermal temperature model, and steam generator and secondary loop models. The core heat power is first transferred to the helium coolant, and then transferred to the secondary loop steam side via the steam generator; the local heat transfer details are equivalent to lumped heat capacity nodes and deviation equations, while hot helium temperature, cold helium temperature, main steam pressure, and steam flow rate are retained as interface variables for the transfer of nuclear thermal disturbances to the mechanical side.

[0053] In some embodiments, a mechanical-side simulation model of a high-temperature gas-cooled reactor unit is constructed based on the granularity constraints of the actuator function. This includes: constructing a grid-connected speed control system sub-model using the unit speed deviation and power deviation as inputs and the main steam valve opening given signal generated by the speed control law as output; following the granularity simplification rules of the actuator function, ignoring the fine hydraulic servo process inside the valve, constructing the main body of the model using the main steam valve opening given signal as input and employing a first-order inertial actuator function that includes opening limit and rate of change limit, and constructing the main steam valve actuator with the actual main steam valve opening as output. The model is constructed by following the granular simplification rules of the actuator function, ignoring the fine hydraulic servo process inside the valve, taking the main steam pressure deviation as input, generating the bypass opening given signal through bypass control logic, using a first-order inertial actuator function that includes opening limit and rate of change limit to construct the main model, and using the actual bypass opening as output to construct the bypass system sub-model; taking the main steam pressure, actual main steam valve opening and actual bypass opening as input, establishing the power calculation relationship based on the steam flow characteristics to construct the main model, and using the unit mechanical power as output to construct the turbine sub-model.

[0054] The steam generator and secondary loop sub-model employs deviation equations to establish dynamic equations for the relevant state variables, including main steam pressure, cold helium temperature, intermediate heat capacity temperature, and secondary loop temperature, ensuring that the integrator inputs are zero under rated standard operating conditions. The corresponding formulas are as follows:

[0055] in, This is the set of state variables for the steam generator and its secondary loop sub-model. State variables The corresponding function on the right-hand side of the dynamic equation; and These are the state variable vector and the input variable vector, respectively; and These are the initial value vectors of the state variables and the initial value vectors of the input variables under the rated standard operating conditions, respectively. This refers to the equivalent temperature state quantity on the second loop side. This is the temperature of cold helium. This refers to the intermediate heat capacity temperature of the steam generator. Main steam pressure.

[0056] The main steam pressure dynamic equation includes at least a heat input compensation term, a steam flow deviation term, a feedwater flow deviation term, and a temperature difference deviation term, with the corresponding formulas as follows: in, The comprehensive pressure drive deviation term of the main steam pressure dynamic equation; This is the thermal input compensation coefficient corresponding to the relative neutron power deviation; This is the temperature difference deviation compensation coefficient; This refers to the intermediate heat capacity temperature of the steam generator. The main steam temperature is calculated from the main steam pressure. This is the rated steam mass flow rate; The main steam specific enthalpy; For specific enthalpy of water supply; This is a relative value for steam flow rate; This is a relative value of the water supply flow rate. This represents the relative value of the water supply flow rate under rated standard operating conditions. The main steam pressure dynamic gain coefficient.

[0057] The grid-connected speed control system sub-model generates the main steam valve opening and regulating steam valve opening based on speed and power deviations; the main steam valve actuator sub-model calculates the effective steam flow entering the turbine based on main steam pressure, main steam valve opening, and overspeed protection signal; the bypass system sub-model generates bypass steam flow based on main steam pressure deviation and bypass control commands, and limits valve opening, opening change rate, and bypass flow through actuator functions. The corresponding formulas are as follows:

[0058] in, This is a speed deviation signal. The given value for the rotational speed, This refers to the rotor angular velocity; This is a power deviation signal. For the power setpoint, This refers to the electromagnetic power of the generator. To adjust the opening of the main steam valve or high-pressure regulating valve. This refers to the opening degree of the intermediate steam valve or intermediate pressure regulating valve. This is an overspeed protection signal; For bypass steam flow rate, This is a bypass control command. Main steam pressure reference value; , , and These are the calculation functions for the main steam valve opening, intermediate steam valve opening, bypass steam flow, and effective steam flow of the main steam valve, respectively. and It includes at least first-order inertia, opening limit, and opening rate of change limit components; It should include at least the main steam pressure deviation calculation, bypass control command limiting, and bypass flow limiting steps; Based on the main steam pressure, main steam valve opening, and The signal is used to calculate the effective steam flow rate entering the turbine.

[0059] The turbine sub-model calculates the turbine mechanical power based on steam flow rate, main steam pressure, main steam valve opening, and regulating valve opening. In steady state, the turbine mechanical power matches the generator electromagnetic power. In steady state: in, For steam turbine mechanical power; This is a function for calculating the mechanical power of a steam turbine. This is a relative value of steam flow rate. Main steam pressure, To adjust the opening of the main steam valve or high-pressure regulating valve. This refers to the opening degree of the intermediate steam valve or intermediate pressure regulating valve. This refers to the electromagnetic power of the generator.

[0060] In some embodiments, a simulation model of the electric side of a high-temperature gas-cooled reactor unit is constructed based on the granularity constraints of the equivalent grid boundary. This includes: following the granularity simplification rules of the equivalent grid boundary, the external grid is equivalent to an infinite grid and an equivalent impedance boundary; the main body of the model is constructed based on the electromechanical transient equations of the synchronous generator, with the unit terminal electrical quantities and rotor operating parameters as inputs; the active power, reactive power, and terminal voltage of the unit are used as outputs to construct a sub-model of the synchronous generator and the grid; the excitation regulation given signal is generated by the power system stabilizer damping regulation logic and excitation control law calculations, with the unit speed deviation, terminal voltage deviation, and power fluctuation as inputs; the main body of the model is constructed based on the dynamic response equation of the excitation system; and the excitation system and power system stabilizer sub-model are constructed with the actual excitation voltage and excitation current as outputs.

[0061] The synchronous generator and grid sub-model uses electromechanical dynamic equations to describe the relationship between the turbine mechanical power, generator electromagnetic power, and rotor angular velocity: in, The generator rotor power angle, This is the reference value for synchronous angular velocity. The rotor angular velocity, The inertial time constant, For the mechanical power of the steam turbine, For the electromagnetic power of the generator, is the damping coefficient.

[0062] The power system stabilizer sub-model generates a stabilization supplementary signal based on the rotor angular velocity deviation signal, the electromagnetic power deviation signal, or a combination of both. When the power system stabilizer gain is zero, the power system stabilizer is out of operation; when the power system stabilizer gain is greater than zero, the power system stabilizer is in operation. The corresponding formulas are as follows:

[0063] in, To provide a stable additional signal for the output of the power system stabilizer; For power system stabilizer gain; For the transfer function of the power system stabilizer; The input deviation signal is used to stabilize the power system. The input deviation signal includes the rotor angular velocity deviation signal, the electromagnetic power deviation signal, or a combination of the two.

[0064] like Figure 6 As shown, in the coupled structure of main steam valve / bypass—grid-connected speed regulation—steam turbine—generator—excitation system, the grid-connected speed regulation system generates main steam valve opening, regulating steam valve opening, and overspeed protection signals based on power command, speed feedback, electromagnetic power feedback, and main steam pressure feedback. The main steam valve actuator generates the steam flow rate entering the steam turbine based on the main steam pressure, valve opening, and OPC signal. The bypass system generates the bypass steam flow rate based on the main steam pressure deviation or bypass control command. The steam turbine outputs mechanical power based on the steam flow rate and valve opening. The synchronous generator and grid model output electromagnetic power and rotor angular velocity based on the mechanical power and excitation voltage. The excitation system and power system stabilizer output excitation voltage and stabilization auxiliary signals based on the electrical side feedback signal.

[0065] The main steam valve actuator sub-model calculates the effective steam flow entering the turbine based on the main steam valve opening command, main steam pressure, and overspeed protection signal. The bypass system sub-model calculates the bypass steam flow based on the main steam pressure deviation and bypass control command, and influences the effective steam flow entering the turbine through flow diversion. Through these settings, changes in main steam pressure, speed regulating valve operation, and bypass steam diversion can collectively affect the turbine's mechanical power.

[0066] In some embodiments, the nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units further includes the step of performing simulation verification on the integrated nuclear-thermal-electric coupling simulation model under each preset operating condition and generating simulation verification results.

[0067] The preset operating conditions can include zero-disturbance steady-state holding condition, power increase step condition, power decrease step condition, inlet helium temperature disturbance condition, thermal power and mechanical power coordinated disturbance condition, speed regulation small disturbance condition, power system stabilizer switching comparison condition, and comparison condition between the complete coupled model and the fixed heat source boundary model. The zero-disturbance steady-state holding condition is used to verify that relative neutron power, external reactivity, main helium flow rate, hot helium temperature, cold helium temperature, intermediate heat capacity temperature, main steam pressure, feedwater flow rate, steam flow rate, turbine mechanical power, and generator electromagnetic power remain stable under rated operating conditions.

[0068] The power increase / decrease step conditions are used to verify the coordinated response of relative neutron power, main helium flow rate, steam flow rate, feedwater flow rate, turbine mechanical power, and generator electromagnetic power to changes in power setpoint, respectively. The inlet helium temperature disturbance condition is used to verify the dynamic impact of inlet helium temperature changes on relative neutron power via hot helium temperature, core temperature, reflector temperature, and temperature feedback reactivity. The power system stabilizer switching comparison condition is used to set the power system stabilizer to be deactivated and activated under the same disturbance, comparing the responses of electromagnetic power, rotor angular velocity, excitation voltage, and stabilization auxiliary signals. The comparison between the fully coupled model and the fixed heat source boundary model is used to compare the responses of hot helium temperature, main steam pressure, generator electromagnetic power, and rotor angular velocity under the same reactor power command disturbance, in order to verify the role of retaining the slow nuclear-side thermal variables and the dynamic state of the steam generator in the characterization of nuclear-thermal-electric disturbance transmission. The fixed heat source boundary model is a comparison model in which at least one of the hot helium temperature, main steam pressure, or steam flow rate is set to a rated value, an externally given value, or a first-order inertial boundary value, and at least some of the dynamic feedback relationships between the boundary variables and the relevant sub-models on the nuclear and thermal sides are severed.

[0069] This embodiment uses various operating conditions, including zero-disturbance steady-state maintenance, power step increase, power step decrease, inlet helium temperature disturbance, coordinated disturbance of thermal power and mechanical power, small speed regulation disturbance, power system stabilizer switching comparison, and comparison between the complete coupled model and the fixed heat source boundary model, to simulate and verify the integrated nuclear-thermal-electric coupling model.

[0070] In a comparative operating condition between the fully coupled model and the fixed heat source boundary model, the same reactor power command step disturbance was set, and simulations were performed on both models. The fully coupled model preserved the dynamic connections between the nuclear thermal side, primary loop, steam generator, turbine, synchronous generator, excitation system, and power system stabilizer. The fixed heat source boundary model kept the turbine, synchronous generator, excitation system, power system stabilizer, and equivalent grid parameters unchanged, treating the nuclear thermal side and secondary loop side as fixed heat source boundaries, and fixing the hot helium temperature and main steam pressure.

[0071] Simulation results are as follows Figure 7 As shown, under the step change of reactor power command, the hot helium temperature, main steam pressure, generator electromagnetic power, and rotor angular velocity in the complete coupled model all undergo corresponding dynamic changes. The fixed heat source boundary model, due to the fixed boundaries of hot helium temperature and main steam pressure, struggles to represent the process of reactor power disturbances being transmitted from the nuclear thermal side and the secondary loop to the electromechanical side. This comparison demonstrates that retaining the slow nuclear-side thermal variables and the dynamic state of the steam generator is beneficial for characterizing the nuclear-thermal-electric disturbance transmission relationship in high-temperature gas-cooled reactor units.

[0072] In the zero-disturbance steady-state maintenance condition, the relative neutron power setpoint, power setpoint, main helium flow rate setpoint, feedwater flow rate, and steam flow rate are all set to their rated values: in, Given a relative neutron power value, For the power setpoint, The setpoint for the main helium flow rate. This is a relative value of steam flow rate. This is a relative value of the water supply flow rate.

[0073] Simulation results are as follows Figure 8 As shown, the relative neutron power, main helium flow rate, main steam pressure, feedwater flow rate, turbine mechanical power, and electromagnetic power all remain near their rated steady-state values, indicating that the established model does not experience continuous drift under undisturbed conditions.

[0074] In the power step-up operation, the relative neutron power setpoint and the power setpoint are set from 1 to 1.02: Simulation results are as follows Figure 9 As shown, the relative neutron power, main helium flow rate, main steam pressure, feedwater flow rate, turbine mechanical power, and electromagnetic power all converge to near the new steady-state values. The thermal helium temperature recovers to the corresponding thermal equilibrium state after a short-term change, indicating that the model can characterize the coordinated response of the nuclear thermal side and the electromechanical side during the power increase process.

[0075] In the power reduction step condition, the relative neutron power setpoint and the power setpoint are set from 1 to 0.98: Simulation results are as follows Figure 10 As shown, the relative neutron power, main helium flow rate, main steam pressure, feedwater flow rate, turbine mechanical power, and electromagnetic power decrease and stabilize to the corresponding levels as the power setpoint decreases, indicating that the model can maintain the consistent response direction of each subsystem during the power reduction process.

[0076] In the inlet helium temperature disturbance condition, a step disturbance is set for the inlet helium temperature: in, For the inlet helium temperature, This is the initial value of the inlet helium temperature. This represents the inlet helium temperature disturbance.

[0077] Simulation results are as follows Figure 11As shown, changes in the inlet helium temperature cause changes in the hot helium temperature, core temperature, and reflector temperature. These temperature changes affect the overall reactivity through temperature feedback reactivity, causing a short-term shift in the relative neutron power before it recovers to near the given value. This indicates that the temperature-side coupling direction is correct.

[0078] In a disturbance condition coordinating thermal and mechanical power, at least one of the following setpoints—relative neutron power, main helium flow rate, steam flow rate, or power—was set to undergo a step change. The coordinated responses of hot helium temperature, cold helium temperature, main steam pressure, steam flow rate, turbine mechanical power, and generator electromagnetic power were observed. Simulation results show that the thermal-side state variables can correspond to changes in main steam pressure and steam flow rate with changes in nuclear-side power. The turbine mechanical power and generator electromagnetic power can re-achieve a matching state after the disturbance, indicating that the model can characterize the dynamic coordination relationship during the transfer of thermal power to mechanical power.

[0079] In the case of small speed disturbance, the power setpoint is set to increase briefly and then return to normal: Simulation results are as follows Figure 12 As shown, the main steam valve opening and regulating steam valve opening change with the power setpoint in a short time. The turbine mechanical power and generator electromagnetic power generate a short-time response and recover to near the rated value after the disturbance is removed. The reactor body and main helium flow do not show a continuous deviation, indicating that the coupling relationship between the grid-connected speed control system and the turbine generator is correct.

[0080] In the power system stabilizer switching comparison scenario, the power system stabilizer is set to be deactivated and activated for the same small speed regulation disturbance: in, For power system stabilizer gain, The gain setting value for when the power system stabilizer is put into operation.

[0081] Simulation results are as follows Figure 13 As shown, the generator electromagnetic power, rotor angular velocity, and excitation voltage can all recover to stability after disturbance under both operating conditions. When the power system stabilizer is activated, the stabilization auxiliary signal participates in the excitation regulation and eventually returns to near zero, indicating that the excitation system and the power system stabilizer can be connected to the nuclear-thermal-electric coupling integrated model and used for electrical side stability analysis.

[0082] In some embodiments, please refer to Figure 14 The present application provides a nuclear-thermal-electric coupling modeling and simulation system 140 for a high-temperature gas-cooled reactor unit, comprising: a partitioning module 141, a first modeling module 142, and a second modeling module 143.

[0083] The partitioning module 141 is used to divide the high-temperature gas-cooled reactor unit into multiple dominant dynamic modules based on the module selection principle, and to determine the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit.

[0084] The first modeling module 142 is used to use the equivalent non-dominant details as modeling granularity constraints, perform simulation modeling for each dominant dynamic module, construct simulation models corresponding to each dominant dynamic module, and form a set of sub-models for the high-temperature gas-cooled reactor unit model.

[0085] The second modeling module 143 is used to connect the sub-models of the high-temperature gas-cooled reactor unit model in a closed loop according to the forward energy transfer link and the reverse control feedback link of the high-temperature gas-cooled reactor unit, using the nuclear-thermal-electric standardized interface variables as the link, to form a nuclear-thermal-electric coupling integrated simulation model of the high-temperature gas-cooled reactor unit.

[0086] It should be noted that the high-temperature gas-cooled reactor nuclear-thermal-electric coupling modeling and simulation system provided in this application embodiment and the high-temperature gas-cooled reactor nuclear-thermal-electric coupling modeling and simulation method provided in this application embodiment are based on the same inventive concept. Therefore, the specific implementation of this embodiment can refer to the implementation of the aforementioned high-temperature gas-cooled reactor nuclear-thermal-electric coupling modeling and simulation method, and the repeated parts will not be described again.

[0087] In some embodiments, an electronic device provided in this application includes a processor and a memory; the memory stores a computer program, wherein the computer program, when executed by the processor, implements the above-described nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units.

[0088] This application also provides a non-transitory computer storage medium storing a computer program that, when executed by a processor, implements the aforementioned nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units. This computer-readable medium may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into that device / apparatus / system. The aforementioned computer-readable medium carries one or more programs, which, when executed, implement the method as described in the embodiments of this application.

[0089] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0090] Those skilled in the art will understand that the features described in the various embodiments of this application can be combined and / or combined in various ways without departing from the spirit and teachings of this application, even if such combinations or combinations are not explicitly described in this application. All such combinations and / or combinations fall within the scope of this application. Therefore, the scope of this application should not be limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for modeling and simulating the nuclear-thermal-electric coupling of a high-temperature gas-cooled reactor unit, characterized in that, include: Based on the principle of module selection, the high-temperature gas-cooled reactor unit is divided into multiple dominant dynamic modules, and the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit are determined. Using the equivalent non-dominant details as modeling granularity constraints, simulation modeling is performed separately for each dominant dynamic module, and simulation models corresponding to each dominant dynamic module are constructed to form a set of sub-models for the high-temperature gas-cooled reactor unit model. Using the standardized interface variables of nuclear-thermal-electricity as a link, the sub-models of the high-temperature gas-cooled reactor unit model are connected in a closed loop according to the forward energy transfer link and the reverse control feedback link of the high-temperature gas-cooled reactor unit, forming an integrated simulation model of nuclear-thermal-electricity coupling of the high-temperature gas-cooled reactor unit.

2. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 1, characterized in that, The module selection principle divides the high-temperature gas-cooled reactor unit into multiple dominant dynamic modules and identifies the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit, including: Based on the dominant roles of the dynamic processes on the nuclear side, thermal side, mechanical side, and electric side of the high-temperature gas-cooled reactor unit, the high-temperature gas-cooled reactor unit is divided into a nuclear side module, a thermal side module, a mechanical side module, and an electric side module. The nuclear side module includes a reactor power control module and a core neutron dynamics module. The thermal side module includes a primary loop helium thermal temperature module and a steam generator and secondary loop module. The mechanical side module includes a grid-connected speed control system module, a main steam valve actuator module, a bypass system module, and a turbine module. The electric side module includes a synchronous generator and grid module, an excitation system, and a power system stabilizer module. The core three-dimensional power distribution, local flow channel heat transfer details, detailed valve hydraulic servo process, and actual power grid detailed grid structure are simplified by equivalent means to determine the corresponding equivalent point reactor dynamics, lumped heat capacity nodes, actuator functions, and equivalent power grid boundaries.

3. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 2, characterized in that, The step of using the equivalent non-dominant details as modeling granularity constraints, performing simulation modeling for each dominant dynamic module separately, and constructing a simulation model corresponding to each dominant dynamic module includes: Based on the particle size constraints of the aforementioned point-pile dynamics, a core-side simulation model of a high-temperature gas-cooled reactor unit is constructed. Based on the granularity constraints of the lumped heat capacity nodes, a hot-side simulation model of a high-temperature gas-cooled reactor unit is constructed. Based on the granularity constraints of the actuator function, a mechanical-side simulation model of the high-temperature gas-cooled reactor unit is constructed. Based on the granularity constraints of the equivalent power grid boundary, an electric-side simulation model of a high-temperature gas-cooled reactor unit is constructed.

4. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 3, characterized in that, The core-side simulation model of the high-temperature gas-cooled reactor unit, based on the particle size constraints of the point reactor dynamics, includes: Using the relative neutron power, characterized by lumped characteristics under point reactor dynamics constraints, as the control object, the deviation between the given relative neutron power and the actual relative neutron power is taken as the input. The input is used to perform proportional-integral calculation to generate the initial external reactivity. The external reactivity output by setting the amplitude limit constraint on the initial external reactivity is taken as the output to construct a reactor power control sub-model. Following the granular simplification rules of point reactor dynamics, the main body of the model is constructed using six sets of delayed neutron point reactor dynamics equations. The total reactivity obtained by superimposing the external reactivity and the temperature feedback reactivity is used as the driving input of the core neutron dynamics sub-model, and the relative neutron power is used as the output to construct the core neutron dynamics sub-model. The temperature feedback reactivity is jointly determined by the core temperature deviation and the reflector temperature deviation.

5. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 3, characterized in that, The construction of a hot-side simulation model for a high-temperature gas-cooled reactor unit based on the granularity constraints of the lumped heat capacity nodes includes: The core structure, reflector, and primary loop helium are respectively represented as lumped heat capacity nodes. The core thermal power is used as the driving input to establish the thermal balance differential equations of each node to construct the main body of the model. The core temperature, reflector temperature and primary loop hot helium outlet temperature are used as the outputs to construct the primary loop helium thermal temperature sub-model. The heat exchange metal wall and the secondary loop steam-water working fluid are equivalent to lumped heat capacity nodes. The primary loop hot helium outlet temperature is used as the driving input. The dynamic calculation relationship is established in the form of deviation equations to construct the main body of the model. The main steam pressure and main steam temperature state variables are used as outputs to construct the steam generator and secondary loop sub-model.

6. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 3, characterized in that, The mechanical-side simulation model of the high-temperature gas-cooled reactor unit, constructed based on the granular constraints of the actuator function, includes: Using the unit speed deviation and power deviation as inputs, and the main steam valve opening given signal generated by the speed control law as output, a sub-model of the grid-connected speed control system is constructed. Following the granular simplification rules of the actuator function, ignoring the fine process of hydraulic servo inside the valve, the main body of the model is constructed using the given signal of the main steam valve opening as input and a first-order inertial actuator function containing opening limit and rate of change limit. The main steam valve actuator sub-model is constructed using the actual main steam valve opening as output. Following the granular simplification rules of the actuator function, ignoring the fine process of hydraulic servo inside the valve, the main steam pressure deviation is used as input, and the bypass opening given signal is generated through bypass control logic. The main body of the model is constructed using a first-order inertial actuator function that includes opening limit and rate of change limit, and the bypass system sub-model is constructed using the actual bypass opening as output. Using the main steam pressure, actual main steam valve opening, and actual bypass opening as inputs, the main model is constructed by establishing power calculation relationships based on steam flow characteristics, and the turbine sub-model is constructed by using the unit mechanical power as output.

7. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 3, characterized in that, The electric-side simulation model of the high-temperature gas-cooled reactor unit, based on the granular constraints of the equivalent power grid boundary, includes: Following the granular simplification rules of the equivalent power grid boundary, the external power grid is equivalent to an infinite power grid and an equivalent impedance boundary. The main body of the model is constructed based on the electromechanical transient equations of the synchronous generator, with the unit terminal electrical quantities and rotor operating parameters as inputs. The active power, reactive power, and terminal voltage of the unit are used as outputs to construct the synchronous generator and power grid sub-models. Using the unit speed deviation, terminal voltage deviation and power fluctuation as inputs, the excitation regulation given signal is generated through the power system stabilizer damping regulation logic and excitation control law calculation. The main body of the model is constructed based on the dynamic response equation of the excitation system, and the excitation system and power system stabilizer sub-models are constructed with the actual excitation voltage and excitation current as outputs.

8. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 1, characterized in that, The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units also includes: The integrated simulation model of nuclear-thermal-electric coupling is simulated and verified under various preset working conditions, and simulation verification results are generated.

9. The nuclear-thermal-electric coupling modeling and simulation method for high-temperature gas-cooled reactor units as described in claim 8, characterized in that, The preset operating conditions include zero-disturbance steady-state maintenance condition, power increase step condition, power decrease step condition, inlet helium temperature disturbance condition, thermal power and mechanical power coordinated disturbance condition, speed regulation small disturbance condition, power system stabilizer switching comparison condition, and complete coupled model and fixed heat source boundary model comparison condition.

10. A nuclear-thermal-electric coupling modeling and simulation system for a high-temperature gas-cooled reactor unit, characterized in that, include: The module division is used to divide the high-temperature gas-cooled reactor unit into multiple dominant dynamic modules based on the module selection principle, and to determine the equivalent non-dominant details in the nuclear-thermal-electric coupling process of the high-temperature gas-cooled reactor unit. The first modeling module is used to take the equivalent non-dominant details as modeling granularity constraints, perform simulation modeling for each dominant dynamic module, construct simulation models corresponding to each dominant dynamic module, and form a set of sub-models for the high-temperature gas-cooled reactor unit model. The second modeling module is used to connect the sub-models of the high-temperature gas-cooled reactor unit model in a closed loop according to the forward energy transfer link and the reverse control feedback link of the high-temperature gas-cooled reactor unit, using the nuclear-thermal-electric standardized interface variables as the link, to form an integrated simulation model of the nuclear-thermal-electric coupling of the high-temperature gas-cooled reactor unit.

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