Supercritical carbon dioxide cycle power generation control system and method for metal cooling reactor

Abstract

The invention discloses a metal cooling reactor supercritical carbon dioxide cycle power generation control system and method. The system comprises an intermediate heat exchanger, a circulating pump, a reactor, a pressure reducing valve, a turbine, a heat regenerator, a compressor, a storage tank air inlet valve, a storage tank, a storage tank exhaust valve, a cooler, a buffer tank, a water pump, a water pool, a power generator and a control module. The control module comprises a turbine inlet temperature and pressure control module, a compressor inlet temperature and pressure control module, a reactor inlet temperature control module, a rotating speed control module, a flow control module and the like; and the control modules are respectively used for accurately regulating and controlling turbine inlet conditions, compressor working states, reactor operating temperatures, working medium flows of turbines and compressors and working medium flows from compressor outlets to heat regenerator hot side outlets. The wide-load, efficient and stable operation of the supercritical carbon dioxide cycle power generation process is achieved by finely regulating and controlling the working parameters of all the assemblies and controlling the load change of the system in a zoning mode.

Description

Technical Field

[0001] The present invention belongs to the technical field of new circulation system control, and relates to a supercritical carbon dioxide circulation power generation control system and method for a metal-cooled reactor. Background Art

[0002] With the increasing global demand for efficient, clean, and flexible energy solutions, the combined technology of liquid metal-cooled reactors and supercritical carbon dioxide ( ) circulation power generation systems is gradually becoming a research hotspot. This combination of cutting-edge technologies has significant advantages in improving energy conversion efficiency, reducing carbon emissions, and enhancing system flexibility, especially in special application scenarios with extremely high requirements for safety, response speed, and wide-load operation capabilities, such as nuclear submarine power systems, where its potential is particularly prominent.

[0003] As the core of deep-sea strategic forces, nuclear submarines have extremely demanding requirements for the compactness, reliability, and efficiency of their power systems. Traditional power generation systems often struggle to meet these conditions simultaneously, especially within the space-constrained interior of a nuclear submarine. Therefore, a supercritical carbon dioxide circulation power generation system with a coaxial arrangement of a turbine and a compressor has become an ideal solution. However, this design requires the turbine speed and the compressor speed to change synchronously, making it difficult to simultaneously meet the optimal speed requirements of both under different load, temperature, pressure, and other conditions, resulting in a poorer adaptability of the unit under complex and variable operating conditions; in addition, to ensure the stability and reliability of synchronous regulation, the operating range of the unit may be restricted, so it is difficult to adapt to the load requirements of nuclear submarines under different operating conditions. Summary of the Invention

[0004] The purpose of the present invention is to solve the technical problem of unstable system operation caused by complex operating conditions in the prior art, and to provide a supercritical carbon dioxide circulation power generation control system and method for a metal-cooled reactor.

[0005] To achieve the above object, the present invention adopts the following technical solutions: The first aspect of the present invention provides a supercritical carbon dioxide circulation power generation control system for a metal-cooled reactor, including an intermediate heat exchanger, a reactor, a turbine, a recuperator, a cooler, a compressor, a storage tank, a generator, and a control module; The hot-side outlet of the intermediate heat exchanger is connected to the reactor inlet, and the hot-side inlet of the intermediate heat exchanger is connected to the reactor outlet; The cold-side outlet of the intermediate heat exchanger is connected to the inlet of the turbine; the outlet of the turbine is connected to the hot-side inlet of the regenerator; the hot-side outlet of the regenerator is connected to the hot-side inlet of the cooler, and the hot-side outlet of the cooler is connected to the inlet of the compressor; the outlet of the compressor is respectively connected to the hot-side outlet of the regenerator and the cold-side inlet of the regenerator; the cold-side outlet of the regenerator is connected to the cold-side inlet of the intermediate heat exchanger; a storage tank is arranged between the outlet of the compressor and the connection to the hot-side outlet of the regenerator; The turbine, the generator and the compressor are arranged coaxially in sequence; The control module includes: A core inlet temperature control module for controlling the outlet temperature of the reactor; A turbine inlet temperature control module for controlling the turbine inlet temperature; A turbine inlet pressure control module for controlling the turbine inlet pressure; A compressor inlet temperature control module for controlling the compressor inlet temperature; A compressor inlet pressure control module for controlling the compressor inlet pressure; A reactor inlet temperature control module for controlling the reactor inlet temperature; A speed control module for controlling the working fluid flow rates of the turbine and the compressor; A flow control module for controlling the working fluid flow rates from the outlet of the compressor to the storage tank and from the storage tank to the hot-side inlet of the cooler.

[0006] Furthermore, a circulation pump is arranged between the hot-side outlet of the intermediate heat exchanger and the reactor inlet, and the turbine inlet temperature control module controls the turbine inlet temperature by adjusting the speed of the circulation pump.

[0007] Furthermore, a pressure reducing valve is arranged at the front section of the inlet of the turbine, and the turbine inlet pressure control module controls the turbine inlet pressure by adjusting the opening degree of the pressure reducing valve.

[0008] Furthermore, a buffer tank is arranged between the hot-side outlet of the cooler and the inlet of the compressor.

[0009] Furthermore, a water tank is connected to the cold-side outlet of the cooler; the water tank is connected to the cold-side inlet of the cooler.

[0010] Furthermore, a water pump is arranged between the water tank and the cold-side inlet of the cooler. Furthermore, the compressor inlet temperature control module controls the compressor inlet temperature by adjusting the speed of the water pump.

[0011] Furthermore, an intake valve is arranged at the inlet of the storage tank, and an exhaust valve is arranged at the outlet. The compressor inlet pressure control module controls the compressor inlet pressure by adjusting the opening and closing of the intake valve and the exhaust valve.

[0012] Furthermore, the flow control module controls the turbine inlet flow rate and the compressor inlet flow rate by adjusting the opening degrees of the intake valve and the exhaust valve.

[0013] The second aspect of the present invention provides a control method for supercritical carbon dioxide cycle power generation of a metal-cooled reactor, including the following steps: In the medium and high load regions, the load is adjusted by using the speed control method, specifically: Adjust the speed of the turbine to match the speed with the maximum turbine isentropic efficiency for the current flow rate; Reduce the speed so that the working fluid flow rate changes linearly, and keep the turbine inlet temperature constant by controlling the speed of the circulation pump to adjust the flow rate of the coolant in the reactor; Adjust the opening and closing states of the intake valve and the exhaust valve of the storage tank to keep the compressor inlet pressure constant; Control the speed of the water pump to adjust the cooling water flow rate to keep the compressor inlet temperature constant, and make the reactor inlet temperature decrease slightly first and then increase slightly by adjusting the depth of insertion of the control rods of the reactor into the core; In the low load region, the load can be adjusted by using the turbine inlet pressure control method, specifically: Keep the low speed of the turbine unchanged, and reduce the turbine inlet pressure by reducing the opening degree of the pressure reducing valve in front of the turbine; Adjust the opening degrees of the intake valve and the exhaust valve of the storage tank to control the working fluid flow rate in the system to decrease linearly; Adjust the speed of the circulation pump to change the coolant flow rate of the reactor to keep the turbine inlet temperature constant; Adjust the opening and closing states of the intake valve and the exhaust valve of the storage tank to keep the compressor inlet pressure constant; Adjust the speed of the water pump to change the cooling water flow rate to keep the compressor inlet temperature constant, and increase the reactor inlet temperature by adjusting the depth of insertion of the reactor control rods into the core.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a supercritical carbon dioxide cycle power generation control system for a metal-cooled reactor. The turbine inlet temperature control module and the turbine inlet pressure control module built into the system can precisely adjust the operating conditions of the turbine, optimize its performance, and extend its service life. At the same time, the compressor inlet temperature and pressure control module ensures the stable operation of the compressor, avoiding failures caused by compressor surges. The speed control module precisely controls the working fluid flow rate and the performance of the rotating machinery by adjusting the speeds of the turbine and the compressor. This function not only helps to maintain the pressure balance within the system but also enables flexible adjustment of the power generation according to actual needs, improving the response speed and flexibility of the system. The reactor inlet temperature control module can ensure the reactor operates under safe and stable conditions, effectively preventing a decrease in reaction efficiency or safety hazards caused by excessively high or low temperatures. The flow control module allows the system to flexibly adjust the working fluid flow rate from the compressor outlet to the inlet of the storage tank and from the outlet of the storage tank to the inlet of the hot side of the cooler according to external load changes or maintenance requirements, thereby changing the main circulation flow rate. This function not only improves the adaptability and flexibility of the system but also helps to optimize energy distribution and reduce unnecessary energy consumption.

[0015] Furthermore, the supercritical carbon dioxide cycle power generation control method for the metal-cooled reactor of the present invention ensures the wide-load operation of the power generation system by controlling the load changes of the system in zones. By using the speed control method in the medium and high load zones and using a speed control function with flow rate as a variable, it maintains the efficient work of the turbine and realizes the efficient power generation of the system in the medium and high load zones. By using the turbine inlet pressure control method in the low load zone, it solves the low efficiency problem of the turbine bypass control method and avoids the safety risk of coolant solidification of the turbine inlet temperature control method, realizing the efficient power generation of the system in the low load zone.

[0016] Furthermore, in the supercritical carbon dioxide cycle power generation control method of the metal cooling reactor of the present invention, by precisely adjusting the optimal matching of the turbine speed and the current flow rate, it ensures that the turbine operates at the maximum isentropic efficiency, thereby improving the energy conversion efficiency of the entire cycle system. Adjusting the turbine speed within the range of 40% - 110% of the rated speed realizes the linear change of the working fluid flow rate, which not only enhances the response speed of the system but also ensures the accuracy and stability of load regulation. By adjusting the speed of the circulation pump to maintain a constant turbine inlet temperature and by adjusting the inlet and exhaust valves of the storage tank to keep the compressor inlet pressure stable, it effectively avoids the influence of temperature and pressure fluctuations on the system performance. By adjusting the insertion depth of the reactor control rod, the inlet temperature of the reactor can be precisely controlled, further enhancing the adaptability and flexibility of the system to load changes. In the low-load area, keeping the turbine speed at 40% of the rated speed unchanged and controlling the turbine inlet pressure by adjusting the opening of the pressure-reducing valve in front of the turbine simplifies the control logic and reduces the instability of the system at low loads. By adjusting the opening of the inlet and exhaust valves of the storage tank, a linear decrease in the working fluid flow rate within the system is achieved, ensuring the stable operation of the system at low loads. Similarly, by adjusting the speed of the circulation pump and the water pump, the constant turbine inlet temperature and compressor inlet temperature are maintained respectively, and by adjusting the storage tank valve to keep the compressor inlet pressure stable, the stability of the system at low loads is further enhanced. In the low-load area, the turbine bypass control method and the turbine inlet temperature control method are not adopted. The main considerations are as follows: The turbine bypass control method adjusts the load by controlling the opening of the turbine bypass valve to change the ratio of the main path and branch flow rates. Although this method has the ability to quickly adjust the load, since the working fluid flow rate within the system remains unchanged and the turbine operates at a low speed in the low-load area, the isentropic efficiency of the turbine is low and the unit work of the turbine drops significantly. At the same time, this method causes the temperature of the coolant in the reactor to rise and the reactor power to increase. This change makes the power generation efficiency of the system lower than that of the turbine inlet pressure control method.

[0017] The turbine inlet temperature control method adjusts the load by controlling the speed of the circulation pump to change the reactor coolant flow rate and thus controlling the turbine inlet temperature. However, this method will cause the reactor coolant temperature to change violently, bringing a risk of thermal shock to the core equipment of the power generation system. At low loads, it may cause the reactor inlet temperature to drop to the freezing point temperature, posing a huge hidden danger to the safe operation of the reactor.

[0018] Adopting the method of the present invention not only enhances the response speed of the system, ensures the power generation efficiency, but also guarantees the accuracy and stability of load regulation. Description of the Drawings

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0020] Figure 1 This is a diagram of the supercritical carbon dioxide cycle power generation control system for the metal cooling reactor of the present invention.

[0021] Among them: 1 - Intermediate heat exchanger; 2 - Circulation pump; 3 - Reactor; 4 - Pressure reducing valve; 5 - Turbine; 6 - Regenerator; 7 - Cooler; 8 - Buffer tank; 9 - Compressor; 10 - Intake valve; 11 - Storage tank; 12 - Exhaust valve; 13 - Water pump; 14 - Water pool; 15 - Generator. Specific embodiments

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and marked in the following drawings can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0024] It should be noted that: Similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0025] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0026] In addition, when the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and it does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0027] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, when the terms "arranged", "installed", "connected", and "coupled" appear, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0028] The present invention will be further described in detail below with reference to the accompanying drawings: See Figure 1 , the present invention discloses a supercritical carbon dioxide cycle power generation control system for a metal cooling reactor, including: an intermediate heat exchanger 1, a circulation pump 2, a reactor 3, a pressure reducing valve 4, a turbine 5, a recuperator 6, a cooler 7, a buffer tank 8, a compressor 9, a storage tank inlet valve 10, a storage tank 11, a storage tank exhaust valve 12, a water pump 13, a water pool 14, a generator 15 and a control module; The hot side outlet of the intermediate heat exchanger 1 is connected to the inlet of the reactor 3, and the hot side inlet of the intermediate heat exchanger 1 is connected to the outlet of the reactor 3; the intermediate heat exchanger 1 is used as a heat exchange device, and its hot side is used for heat transfer of the reactor coolant, and the cold side is used for heating the working medium (supercritical carbon dioxide) entering the turbine.

[0029] The cold-side outlet of the intermediate heat exchanger 1 is connected to the inlet of the turbine 5; the outlet of the turbine 5 is connected to the hot-side inlet of the recuperator 6; the hot-side outlet of the recuperator 6 is connected to the inlet of the compressor 9; the outlet of the compressor 9 is respectively connected to the hot-side inlet of the cooler 7 and the cold-side inlet of the recuperator 6; the cold-side outlet of the recuperator 6 is connected to the cold-side inlet of the intermediate heat exchanger 1; a circulation pump 2 is provided between the hot-side outlet of the intermediate heat exchanger 1 and the inlet of the reactor 3; a pressure-reducing valve 4 is provided in the front section of the inlet of the turbine 5; a buffer tank 8 is provided between the hot-side outlet of the recuperator 6 and the inlet of the compressor 9. A cooler 7 is provided between the hot-side outlet of the recuperator 6 and the buffer tank 8; the hot-side outlet of the recuperator 6 is connected to the hot-side inlet of the cooler 7; the hot-side outlet of the cooler 7 is connected to the buffer tank 8. The cold-side outlet of the cooler 7 is connected to a water tank 14; the water tank 14 is connected to the cold-side inlet of the cooler 7. A water pump 13 is provided between the water tank 14 and the cold-side inlet of the cooler 7, and a storage tank 11 is provided between the outlet of the compressor 9 and the hot-side inlet of the cooler. An intake valve 10 is provided at the inlet of the storage tank 11, and an exhaust valve 12 is provided at the outlet; the turbine 5, the generator 15, and the compressor 9 are coaxially arranged in sequence; The control module includes: A core inlet temperature control module for controlling the core inlet temperature of the reactor 3 by adjusting the depth of insertion of the control rods into the core; A turbine inlet temperature control module for controlling the turbine 5 inlet temperature by adjusting the rotational speed of the circulation pump 2; A turbine inlet pressure control module for controlling the turbine 5 inlet pressure by adjusting the opening of the pressure-reducing valve 4; A compressor inlet temperature control module for controlling the compressor 9 inlet temperature by adjusting the rotational speed of the water pump 13; A compressor inlet pressure control module for controlling the compressor 9 inlet pressure by adjusting the opening and closing of the intake valve 10 and the exhaust valve 12; A reactor inlet temperature control module for controlling the reactor 3 inlet temperature by adjusting the depth of insertion of the control rods into the core in the reactor 3; A rotational speed control module for controlling the working fluid flow rates of the turbine 5 and the compressor 9 by adjusting the rotational speeds of the turbine 5 and the compressor 9; A flow control module for controlling the working fluid flow rate from the outlet of the compressor 9 to the inlet of the storage tank 11 or the working fluid flow rate from the outlet of the storage tank 11 to the hot-side inlet of the cooler 7 by adjusting the opening of the intake valve 10 and the exhaust valve 12.

[0030] The working process / working principle of the present invention is as follows: Low-pressure and low-temperature supercritical carbon dioxide enters compressor 9 and is compressed into a high-pressure and low-temperature fluid. Subsequently, it successively enters the cold side of regenerator 6 and the cold side of intermediate heat exchanger 1, absorbs heat and becomes a high-pressure and high-temperature fluid, and then enters pressure-reducing valve 4. The working medium that has passed through pressure-reducing valve 4 enters turbine 5, expands rapidly, and drives turbine 5 to rotate. The rotational motion of turbine 5 drives generator 15 to generate electrical energy through a mechanical transmission device, realizing the conversion from thermal energy to electrical energy. The low-pressure and high-temperature fluid after doing work enters the hot side of regenerator 6 and the hot side of precooler 7 to cool down to the initial state, preparing to enter the next cycle.

[0031] According to the power load demand, the inlet pressure of turbine 5 is controlled by adjusting the opening degree of pressure-reducing valve 4. Reducing the opening degree of pressure-reducing valve 4 increases the pressure drop across pressure-reducing valve 4, thereby reducing the inlet pressure of turbine 5; increasing the opening degree of pressure-reducing valve 4 decreases the pressure drop across pressure-reducing valve 4, thereby increasing the inlet pressure of turbine 5.

[0032] According to the power load demand, the working medium flow rate of the system is controlled by adjusting the rotational speeds of coaxial turbine 5 and compressor 9. Reducing the rotational speed reduces the working medium flow rate within the system, and increasing the rotational speed increases the working medium flow rate within the system.

[0033] According to the power load demand, the working medium flow rate within the system is controlled by adjusting the opening degrees of inlet valve 10 and exhaust valve 12 of storage tank 11. Reducing the opening degree of inlet valve 10 of storage tank 11 and increasing the opening degree of exhaust valve 12 of the storage tank, by discharging high-density working medium into the system, increases the main cycle working medium flow rate; increasing the opening degree of inlet valve 10 of the storage tank and reducing the opening degree of exhaust valve 12 of the storage tank, by collecting low-density working medium into storage tank 11, reduces the main cycle working medium flow rate.

[0034] According to the power load demand, the inlet pressure of compressor 9 is controlled by adjusting the opening and closing states of inlet valve 10 and exhaust valve 12 of the storage tank. Opening inlet valve 10 of the storage tank and closing exhaust valve 12 of the storage tank increases the inlet pressure of compressor 9; closing inlet valve 10 of the storage tank and opening exhaust valve 12 of the storage tank reduces the inlet pressure of compressor 9.

[0035] According to the power load demand, the inlet temperature of reactor 3 is controlled by adjusting the height of the control rod inserted into the reactor core within reactor 3. Raising the height of the control rod increases the inlet temperature of reactor 3; lowering the height of the control rod reduces the inlet temperature of reactor 3.

[0036] According to the power load demand, the cooling water flow rate in water tank 14 is changed by adjusting the rotational speed of water pump 13, thereby controlling the inlet temperature of compressor 9. Reducing the rotational speed of water pump 13 decreases the cooling water flow rate; increasing the rotational speed of water pump 13 increases the cooling water flow rate.

[0037] According to the power load demand, the coolant flow rate in the core of the reactor 3 is changed by adjusting the rotational speed of the circulation pump 2, thereby controlling the inlet temperature of the turbine 5. Reducing the rotational speed of the circulation pump 2 decreases the coolant flow rate; increasing the rotational speed of the circulation pump 2 increases the coolant flow rate.

[0038] According to the power load demand, the working fluid flow rate from the compressor outlet to the inlet of the storage tank and the mass of the working fluid from the outlet of the storage tank to the inlet of the hot side of the cooler are respectively controlled by adjusting the opening degrees of the intake valve 10 and the exhaust valve 12 of the storage tank. Increasing the opening degree of the intake valve 10 reduces the flow rate entering the inlet of the turbine 5; decreasing the opening degree of the intake valve 10 increases the flow rate entering the inlet of the turbine 5; increasing the opening degree of the exhaust valve 12 increases the flow rate entering the inlet of the compressor 9, and decreasing the opening degree of the exhaust valve 12 decreases the flow rate entering the inlet of the compressor 9.

[0039] The present invention provides a control method for supercritical carbon dioxide cycle power generation of a metal-cooled reactor, including: The present invention can achieve full-load regulation from 0% to 100% through load zoning control.

[0040] In the medium and high load regions, the load is regulated by the rotational speed control method. Specifically: adjusting the rotational speed of the turbine 5 to match the rotational speed with the maximum turbine isentropic efficiency for the current flow rate can ensure the efficient work of the turbine 5, thereby achieving a high system power generation efficiency; the rotational speed control is within the range of 40% - 110% of the rated value to prevent resonance problems and unstable operation of the unit. At this time, the working fluid flow rate is linearly changed by adjusting the rotational speed, the coolant flow rate in the reactor 3 is adjusted by controlling the rotational speed of the circulation pump 2 to keep the inlet temperature of the turbine 5 unchanged, the opening and closing states of the intake valve 10 and the exhaust valve 12 of the storage tank 11 are adjusted to keep the inlet pressure of the compressor 9 unchanged, the cooling water flow rate is adjusted by controlling the rotational speed of the water pump 13 to keep the inlet temperature of the compressor 9 unchanged, and the depth of insertion of the control rod of the reactor 3 into the core is adjusted to adjust the inlet temperature of the reactor 3.

[0041] In the low load region, the load can be regulated by the turbine inlet pressure control method. Keeping the rotational speed of the turbine 5 at 40% unchanged, the turbine inlet pressure is reduced by reducing the opening degree of the pressure reducing valve 4 in front of the turbine 5, the working fluid flow rate in the system is linearly decreased by adjusting the opening degrees of the intake valve 10 and the exhaust valve 12 of the storage tank 11, the coolant flow rate of the reactor 3 is changed by adjusting the rotational speed of the circulation pump 2 to keep the inlet temperature of the turbine 5 unchanged, the opening and closing states of the intake valve 10 and the exhaust valve 12 of the storage tank 11 are adjusted to keep the inlet pressure of the compressor 9 unchanged, the cooling water flow rate is changed by adjusting the rotational speed of the water pump 13 to keep the inlet temperature of the compressor 9 unchanged, and the inlet temperature of the reactor 3 is increased by raising the height of the control rod of the reactor 3 inserted into the core.

[0042] A method for reducing the load based on the control method for supercritical carbon dioxide cycle power generation of a metal-cooled reactor in an embodiment of the present invention is as follows: According to the relationship curves of efficiency with flow rate and rotational speed in the turbine performance curve atlas, obtain the turbine rotational speed data points corresponding to the highest turbine isentropic efficiency at each flow rate, fit the data points to establish the optimal rotational speed control function RS = f(m), and input this function as a control signal into the rotational speed control module.

[0043] Starting from 100% load, use the rotational speed control method to reduce the load: Based on the RS = f(m) function, control the rotational speeds of the turbine and the compressor to decrease from 100% rated rotational speed, so that the working fluid flow rate in the system decreases linearly; reduce the rotational speed of the circulation pump to decrease the coolant flow rate in the reactor, and maintain the turbine inlet temperature at 480°C; control the opening and closing states of the intake valve and exhaust valve of the storage tank to maintain the compressor inlet pressure at 7.6 MPa; reduce the rotational speed of the water pump to decrease the cooling water flow rate and maintain the compressor inlet temperature at 32°C; first slowly lower and then slowly raise the height of the control rod inserted into the reactor core to increase the coolant inlet temperature.

[0044] When the rotational speed drops to 40% of the rated rotational speed, the load decreases to 38%, and the rotational speed remains unchanged.

[0045] Switch to the turbine inlet pressure control method to reduce the load: Adjust the opening of the pressure reducing valve to be smaller, increase the pressure drop across the pressure reducing valve, and reduce the turbine inlet pressure; adjust the intake valve of the storage tank to be larger and the exhaust valve to be smaller to control the linear decrease of the working fluid flow rate; reduce the rotational speed of the circulation pump to decrease the coolant flow rate, maintain the turbine inlet temperature at 480°C, adjust the opening and closing states of the intake valve and exhaust valve of the storage tank to maintain the compressor inlet pressure at 7.6 MPa; reduce the rotational speed of the water pump to decrease the cooling water flow rate and maintain the compressor inlet temperature at 32°C; slowly raise the height of the control rod inserted into the reactor core to increase the coolant inlet temperature until the load drops to 0%.

[0046] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A supercritical carbon dioxide cycle power generation control system for a metal cooling reactor, characterized in that It includes an intermediate heat exchanger (1), a reactor (3), a turbine (5), a recuperator (6), a cooler (7), a compressor (9), a storage tank (11), a generator (15) and a control module; The hot-side outlet of the intermediate heat exchanger (1) is connected to the inlet of the reactor (3), and the hot-side inlet of the intermediate heat exchanger (1) is connected to the outlet of the reactor (3); The cold-side outlet of the intermediate heat exchanger (1) is connected to the inlet of the turbine (5); the outlet of the turbine (5) is connected to the hot-side inlet of the recuperator (6); the hot-side outlet of the recuperator (6) is connected to the hot-side inlet of the cooler (7), and the hot-side outlet of the cooler (7) is connected to the inlet of the compressor (9); the outlet of the compressor (9) is respectively connected to the hot-side outlet of the recuperator (6) and the cold-side inlet of the recuperator (6); the cold-side outlet of the recuperator (6) is connected to the cold-side inlet of the intermediate heat exchanger (1); a storage tank (11) is provided between the outlet of the compressor (9) and the connection to the hot-side outlet of the recuperator (6); The turbine (5), the generator (15) and the compressor (9) are coaxially arranged in sequence; The control module includes: A core inlet temperature control module for controlling the outlet temperature of the reactor (3); A turbine inlet temperature control module for controlling the inlet temperature of the turbine (5); A turbine inlet pressure control module for controlling the inlet pressure of the turbine (5); A compressor inlet temperature control module for controlling the inlet temperature of the compressor (9); A compressor inlet pressure control module for controlling the inlet pressure of the compressor (9); A reactor inlet temperature control module for controlling the inlet temperature of the reactor (3); A speed control module for controlling the working fluid flow rates of the turbine (5) and the compressor (9); A flow control module for controlling the working fluid flow rates from the outlet of the compressor (9) to the storage tank (11) and from the storage tank (11) to the hot-side inlet of the cooler (7).

2. The supercritical carbon dioxide cycle power generation control system of the metal cooling reactor according to claim 1, wherein A circulation pump (2) is provided between the hot-side outlet of the intermediate heat exchanger (1) and the inlet of the reactor (3), and the turbine inlet temperature control module controls the inlet temperature of the turbine (5) by adjusting the speed of the circulation pump (2).

3. The supercritical carbon dioxide cycle power generation control system for a metal cooling reactor according to claim 1, wherein A pressure reducing valve (4) is provided in the front section of the inlet of the turbine (5), and the turbine inlet pressure control module controls the inlet pressure of the turbine (5) by adjusting the opening degree of the pressure reducing valve (4).

4. The supercritical carbon dioxide cycle power generation control system for a metal cooling reactor according to claim 1, characterized in that, A buffer tank (8) is provided between the hot-side outlet of the cooler (7) and the inlet of the compressor (9).

5. The supercritical carbon dioxide cycle power generation control system of the metal cooling reactor according to claim 1, wherein The cold-side outlet of the cooler (7) is connected to a water pool (14); the water pool (14) is connected to the cold-side inlet of the cooler (7).

6. The supercritical carbon dioxide cycle power generation control system for a metal cooling reactor according to claim 5, wherein A water pump (13) is provided between the water pool (14) and the cold-side inlet of the cooler (7).

7. The supercritical carbon dioxide cycle power generation control system for a metal cooling reactor according to claim 6, characterized in that, The compressor inlet temperature control module controls the inlet temperature of the compressor (9) by adjusting the speed of the water pump (13).

8. The supercritical carbon dioxide cycle power generation control system of the metal cooling reactor according to claim 1, wherein An air inlet valve (10) is provided at the inlet of the storage tank (11), and an air exhaust valve (12) is provided at the outlet. The compressor inlet pressure control module controls the inlet pressure of the compressor (9) by adjusting the opening and closing of the air inlet valve (10) and the air exhaust valve (12).

9. The supercritical carbon dioxide cycle power generation control system for a metal cooling reactor according to claim 8, characterized in that, The flow control module controls the inlet flow rate of the turbine (5) and the inlet flow rate of the compressor (9) by adjusting the opening degrees of the air inlet valve (10) and the air exhaust valve (12).

10. A control method for supercritical carbon dioxide cycle power generation in a metal-cooled reactor, based on the supercritical carbon dioxide cycle power generation control system of the metal-cooled reactor according to any one of claims 1-9, characterized in that, It includes the following steps: In the medium and high load regions, the load is adjusted by the speed control method, specifically: Adjust the speed of the turbine (5) to match the speed with the maximum turbine isentropic efficiency for the current flow rate; Reduce the speed to make the working fluid flow rate change linearly, and keep the inlet temperature of the turbine (5) constant by controlling the speed of the circulation pump (2) to adjust the coolant flow rate in the reactor (3); Adjust the opening and closing states of the inlet valve (10) and the exhaust valve (12) of the storage tank (11) to keep the inlet pressure of the compressor (9) constant; Control the speed of the water pump (13) to adjust the cooling water flow rate to keep the inlet temperature of the compressor (9) constant, and make the inlet temperature of the reactor (3) decrease slightly first and then increase slightly by adjusting the depth of insertion of the control rods of the reactor (3) into the core; In the low load region, the load can be adjusted by the turbine inlet pressure control method, specifically: Keep the low speed of the turbine (5) constant, and reduce the turbine inlet pressure by reducing the opening of the pressure reducing valve (4) in front of the turbine (5); Adjust the opening of the inlet valve (10) and the exhaust valve (12) of the storage tank (11) to control the linear decrease of the working fluid flow rate in the system; Adjust the speed of the circulation pump (2) to change the coolant flow rate of the reactor (3) to keep the inlet temperature of the turbine (5) constant; Adjust the opening and closing states of the inlet valve (10) and the exhaust valve (12) of the storage tank (11) to keep the inlet pressure of the compressor (9) constant; Adjust the speed of the water pump (13) to change the cooling water flow rate to keep the inlet temperature of the compressor (9) constant, and increase the inlet temperature of the reactor (3) by adjusting the depth of insertion of the control rods of the reactor (3) into the core.

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