Power generation system with load regulation function, and adaptive load regulation method

Abstract

A power generation system with a load regulation function, and an adaptive load regulation method. The power generation system comprises: a reactor (1), a turbine (2), a heat regenerator (4), a cooler (5) and a compressor (6), wherein a power generation working medium returns to the reactor (1) from an outlet of the compressor (6) via the heat regenerator (4) to form a cycle in the power generation system; a compressor bypass (11) that connects the outlet of the compressor (6) and an inlet of the cooler (5) and is provided with a first valve group (21); and a turbine bypass (12) that connects an inlet and an outlet of the turbine (2) and is provided with a second valve group (22). The system further comprises a storage tank (7), wherein an inlet and an outlet of the storage tank (7) are respectively connected to the inlet of the cooler (5) and the outlet of the compressor (6) to form first and second storage tank bypasses (13, 14), which are respectively provided with a third valve group (23) and a fourth valve group (24). By means of the provision of the compressor bypass (11), the turbine bypass (12), heat regenerator bypasses (15, 16), the storage tank bypasses (13, 14) and the related valve groups (21, 22, 23, 24, 25, 26, 27), the amount of a working medium entering each unit in the power generation system can be regulated, thereby adjusting the power output of a generator (3) connected to the turbine (2), and effectively realizing adaptive load regulation, temperature control and working medium re-circulation by utilizing the design of the power generation system.

Description

Power generation system with load regulation function and adaptive load regulation method

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on April 1, 2024, with application number 2024103841587 and application name “Power generation system with load regulation function and adaptive load regulation method”, the entire contents of which are incorporated by reference into the application. Technical Field

[0002] The present application relates to the technical field, and in particular to a power generation system with a load regulation function and an adaptive load regulation method. Background Art

[0003] The Brayton cycle is a thermodynamic cycle whose circulating working fluids include air, steam, and novel supercritical gas media (such as carbon dioxide, helium, and nitrous oxide). The supercritical carbon dioxide Brayton cycle uses supercritical carbon dioxide as the working fluid for power generation. It is a novel power conversion and power generation system that scientifically designs and rationally matches the working fluid characteristics, thermodynamic processes, and system equipment. It boasts high efficiency, compactness, wide applicability, and environmental friendliness, making it a highly promising new energy conversion system. The novel supercritical carbon dioxide power generation system is a small, clean, efficient, and fast-responding closed-loop power generation system. It has multiple feedback loops, and its physical properties change dramatically near the critical point, exhibiting strong nonlinear characteristics. The system's operation is sensitive to these changes, making system behavior analysis and control complex. Its operating mode and control methods differ from those of traditional steam power generation systems, requiring the improvement and development of new system circulation and control operation methods based on the working fluid characteristics, system configuration, and demanding requirements. Comprehensive and systematic research on this topic is lacking in the industry. Therefore, it is necessary to improve the design according to the characteristics of this type of circulation system and propose a full-load load adjustment method to improve the system efficiency and response rate under partial load while ensuring system safety, so as to ensure safe, reliable and economical operation of the system.

[0004] Application Contents

[0005] The main purpose of this application is to provide a power generation system with load regulation function and an adaptive load regulation method to solve the problem of poor load regulation efficiency of the power generation system in the prior art.

[0006] To achieve the above objectives, the present application provides the following technical solutions: a power generation system with a load regulation function, wherein the power generation system includes a reactor, a turbine, a regenerator, a cooler, and a compressor through which a power generation medium flows in sequence, and the power generation medium returns to the reactor from the outlet of the compressor through the regenerator to form a circulation in the power generation system; the output end of the turbine is connected to a generator, and the compressor, the turbine, and the generator are coaxially arranged; and

[0007] a compressor bypass, the compressor bypass connecting the outlet of the compressor and the inlet of the cooler, the compressor bypass being provided with a first valve group;

[0008] a turbine bypass, the turbine bypass connecting the inlet of the turbine and the outlet of the turbine, the turbine bypass being provided with a second valve group;

[0009] The power generation system further includes a storage tank;

[0010] The outlet of the storage tank is connected to the inlet of the cooler to form a first bypass of the storage tank, and the first bypass of the storage tank is provided with a third valve group;

[0011] The storage tank inlet is connected to the compressor outlet to form a second storage tank bypass, and the second storage tank bypass is provided with a fourth valve group.

[0012] Optionally, the power generation system further includes:

[0013] a first bypass of the regenerator, the first bypass of the regenerator connecting the outlet of the compressor and the inlet of the reactor, and the first bypass of the regenerator being provided with a fifth valve group;

[0014] The second bypass of the regenerator is connected to the outlet of the turbine and the inlet of the reactor, and the second bypass of the regenerator is provided with a sixth valve group.

[0015] Optionally, a seventh valve group is provided on the connecting trunk line between the reactor and the turbine.

[0016] Optionally, the first valve group, the second valve group, the third valve group, the fourth valve group, the fifth valve group, the sixth valve group and the seventh valve group all include regulating valves and shut-off valves.

[0017] Optionally, the power generation system also includes a PID control module, which is electrically connected to each valve group. The PID control module is used to issue corresponding adjustment signals based on the speed signal of the turbine and the load signal, temperature, pressure, and flow of the generator to control the opening and closing of each valve group respectively.

[0018] On the other hand, the present application also provides an adaptive load regulation method, which is applied to the power generation system with load regulation function as described above, and the load regulation method includes:

[0019] generating a regulating signal based on a difference between the target load and the current load;

[0020] The first to seventh valve groups are controlled according to the adjustment signal to adjust the load of the power generation system.

[0021] Optionally, the step of controlling the first to seventh valve groups according to the adjustment signal to adjust the load of the power generation system includes:

[0022] When the current load is within a range of 90% to 100% of the full load of the power generation system, the opening and closing and opening degree of the third valve group and the fourth valve group are controlled by the adjustment signal to adjust the load of the power generation system;

[0023] When the current load is within a range of 40% to 90% of the full load of the power generation system, controlling the opening of the seventh valve group by the adjustment signal to adjust the load of the power generation system;

[0024] When the current load is within a range of 20% to 40% of the full load of the power generation system, controlling the openings of the first valve group and the seventh valve group by the adjustment signal to adjust the load of the power generation system;

[0025] When the current load is within the range of 0% to 20% of the full load of the power generation system, the openings of the first valve group and the second valve group are controlled by the adjustment signal to adjust the load of the power generation system.

[0026] Optionally, after the step of controlling the first to seventh valve groups according to the adjustment signal to adjust the load of the power generation system, the method further includes:

[0027] Determining whether the inlet temperature and the outlet temperature of the reactor are both within a preset range;

[0028] If the inlet temperature and the outlet temperature of the reactor are both outside the preset range, the inlet temperature and the outlet temperature of the reactor are adjusted by the fifth valve group and the sixth valve group.

[0029] Optionally, when the current load is within a range of 0% to 20% of the full load of the power generation system, the step of controlling the openings of the first valve group and the second valve group by the adjustment signal to adjust the load of the power generation system includes:

[0030] opening the second valve group or increasing the opening of the second valve group according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload;

[0031] determining whether surge occurs in the compressor;

[0032] If so, open the first valve group or increase the opening of the first valve group.

[0033] Optionally, when the current load is within a range of 20% to 40% of the full load of the power generation system, the step of controlling the openings of the first valve group and the seventh valve group by the adjustment signal to adjust the load of the power generation system includes:

[0034] closing the seventh valve group or reducing the opening of the seventh valve group according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload;

[0035] determining whether surge occurs in the compressor;

[0036] If so, open the first valve group or increase the opening of the first valve group.

[0037] Optionally, when the current load is within a range of 40% to 90% of the full load of the power generation system, the step of controlling the opening of the seventh valve group by the adjustment signal to adjust the load of the power generation system includes:

[0038] The opening of the seventh valve group is reduced according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload.

[0039] Optionally, when the current load is within a range of 90% to 100% of the full load of the power generation system, the step of controlling the opening and closing and the opening degree of the third valve group and the fourth valve group by the adjustment signal to adjust the load of the power generation system includes:

[0040] The third valve group is closed and the fourth valve group is opened or the opening of the fourth valve group is increased according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload.

[0041] Compared with the existing Brayton cycle power generation system, the power generation system of the present application has at least the following beneficial effects: the compressor bypass, turbine bypass, storage tank unit added to the system and the tank bypass established between the storage tank unit and the compressor and regenerator are formed by connecting in the form of branches. Combined with the valve group provided in the bypass, the volume of the working fluid flowing through each unit can be controlled, thereby avoiding the shortcomings and limitations of a single load regulation means when adjusting the load of the power generation system. Combining the characteristics of different regulation means, a load regulation means within the full operating range is proposed. The bypasses cooperate with each other to form a load regulation method that adaptively matches the regulation means according to different power regulation ranges, thereby achieving the effect of improving the system power generation efficiency, stabilizing system parameters, and quickly adjusting the load. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1 is a schematic diagram of the structural principle of an embodiment of a power generation system of the present application;

[0043] FIG2 is a flow chart of the adaptive load regulation method of the present application;

[0044] FIG3 is a control logic diagram of the power generation system of the present application for load regulation through volume control;

[0045] FIG4 is a control logic diagram of the power generation system of the present application for load regulation through speed control;

[0046] FIG5 is a control logic diagram of the power generation system of the present application for load regulation through throttling control;

[0047] FIG6 is a control logic diagram of the power generation system of the present application for load regulation through bypass flow control;

[0048] FIG7 is a control logic diagram of the power generation system of the present application for load regulation through temperature control;

[0049] Explanation of the serial numbers: 1. Reactor; 2. Turbine; 3. Generator; 4. Regenerator; 5. Cooler; 6. Compressor; 7. Storage tank; 11. Compressor bypass; 12. Turbine bypass; 13. First storage tank bypass; 14. Second storage tank bypass; 15. First regenerator bypass; 16. Second regenerator bypass; 21. First valve group; 22. Second valve group; 23. Third valve group; 24. Fourth valve group; 25. Fifth valve group; 26. Sixth valve group; 27. Seventh valve group.

[0050] The realization of the objectives, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0052] The terms "first," "second," and "third" in this application are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of such features. In the description of this application, "multiple" means at least two, for example, two, three, etc., unless otherwise specifically defined. All directional indications in the embodiments of this application (such as up, down, left, right, front, back...) are only used to explain the relative positional relationship, movement, etc. between the components under a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications also change accordingly. In addition, the terms "including" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products, or devices.

[0053] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0054] The Brayton cycle power generation system is a relatively mature form of thermal cycle and is widely used in the field of power generation and thermoelectric conversion. The circulating working fluid includes polymorphic media such as air, steam and supercritical gas. Currently, the power generation system using supercritical carbon dioxide as the circulating working fluid is the most common. The power generation system of this application is explained with supercritical carbon dioxide as the working fluid, but it should be stated that this is not a limitation. Any new working fluid that may be used in the power generation system of this application at present or in the future and achieves the same technical effect as this application without making substantial changes should be included in the scope of protection required by this application.

[0055] In the supercritical carbon dioxide Brayton cycle system, the system is sensitive to the physical property changes near the critical point of the working fluid and the characteristics of the Brayton cycle system itself, which makes it difficult to adjust the load of the system under different working conditions. Therefore,

[0056] One embodiment of the present application provides a power generation system with a load regulation function, the power generation system including a reactor 1, a turbine 2, a regenerator 4, a cooler 5, and a compressor 6 through which a power generation medium flows in sequence, the power generation medium returns to the reactor 1 from the outlet of the compressor 6 through the regenerator 4 to form a circulation in the power generation system; the output end of the turbine 2 is connected to the generator 3, and the compressor 6, the turbine 2, and the generator 3 are coaxially arranged; and a compressor bypass 11, the compressor bypass 11 connecting the outlet of the compressor 6 and the inlet of the cooler 5 and provided with a first valve group 21; a turbine bypass 12, the turbine bypass 12 connecting the inlet of the turbine 2 and the outlet of the turbine 2 and provided with a second valve group 22; the power generation system also includes a storage tank 7; the outlet of the storage tank 7 is connected to the inlet of the cooler 5 to form a first storage tank bypass 13 and provided with a third valve group 23; the inlet of the storage tank 7 is connected to the outlet of the compressor 6 to form a second storage tank bypass 14 and provided with a fourth valve group 24.

[0057] Referring to FIG. 1 , in the power generation system of this embodiment, a circulating working fluid, such as supercritical carbon dioxide, reacts and stores energy in a reactor 1 and flows through a pipeline to a turbine 2, causing the turbine 2 to perform mechanical work by rotating or otherwise. A generator 3 coaxially connected to the turbine 2 moves with the mechanical movement of the turbine 2 to generate electricity.

[0058] Furthermore, the circulation loop of the power generation system is as follows: the regenerator 4 has a cold side and a hot side, the hot side inlet of the regenerator 4 is connected to the outlet of the turbine 2 for circulating working medium to circulate in the power generation system, along the flow direction of the circulating working medium, the hot side outlet of the regenerator 4 is connected to the inlet of the cooler 5, the outlet of the cooler 5 is connected to the inlet of the compressor 6, the outlet of the compressor 6 is connected to the cold side inlet of the regenerator 4, and the compressor 6 is coaxial with the turbine 2 and the generator 3 to realize synchronous rotation, and the cold side outlet of the regenerator 4 is connected to the inlet of the reactor 1, thereby forming a complete closed loop.

[0059] In this embodiment, the outlet of the compressor 6 is also connected to the inlet of the cooler 5 to form a compressor bypass 11, and a first valve group 21 is provided on the bypass, and the inlet of the turbine 2 is connected to the outlet of the turbine 2 to form a turbine bypass 12, and a second valve group 22 is provided on the bypass; see Figure 1, the inlet of the cooler 5 and the inlet of the turbine 2 connected to the compressor bypass 11 and the turbine bypass 12 can be equivalent to the hot side outlet of the regenerator 4 and the outlet of the reactor 1, respectively; or, the bypass is connected to the corresponding position of the circulation trunk in the form of a branch access; at the same time, in this embodiment, a storage tank 7 is added, and the outlet of the storage tank 7 is connected to the inlet of the cooler 5 to form a first storage tank bypass 13, and a third valve group 23 is provided on the bypass, and the inlet of the storage tank 7 is connected to the outlet of the compressor 6 to form a second storage tank bypass 14, and a fourth valve group 24 is provided on the bypass; thereby, a power generation system with a load regulation function provided by the present application is formed, and its load regulation method and principle will be specifically introduced in conjunction with the subsequent implementation methods.

[0060] The above embodiment is the simplest technical solution provided by this application. The load that can be adjusted by this solution is limited and the effect is poor. Therefore, in some embodiments, this application further improves the above power generation system. Optionally, the power generation system further includes:

[0061] A seventh valve group 27 is provided on the main line connecting the reactor 1 and the turbine 2 .

[0062] The seventh valve assembly 27 enables throttling control of the turbine 2 inlet of the power generation system. When the opening of the regulating valve in the seventh valve assembly 27 decreases, the pressure drop across the valve increases. This, on the one hand, reduces the expansion ratio and output power of turbine 2; on the other hand, the overall system resistance increases, flow decreases, and the pressure ratio and outlet pressure of compressor 6 increase. To prevent compressor 6 from entering the surge zone, this requires coordination with the compressor bypass 11 control in the aforementioned embodiment to increase the load shedding depth and enable continued throttling.

[0063] Furthermore, the power generation system also includes: a first regenerator bypass 15, which is connected to the outlet of the compressor 6 and the inlet of the reactor 1 and is provided with a fifth valve group 25; a second regenerator bypass 16, which is connected to the inlet of the reactor 1 and the outlet of the turbine 2 and is provided with a sixth valve group 26.

[0064] The functions of the first bypass 15 and the second bypass 16 of the regenerator are as follows: during the entire load regulation process, each load adjustment needs to determine whether the core inlet and outlet temperatures are within the preset range. If they are not within the preset range, the temperature is regulated by adjusting the valve openings on the first bypass 15 and the second bypass 16 of the regenerator.

[0065] Optionally, each valve group of the first valve group 21 , the second valve group 22 , the third valve group 23 , the fourth valve group 24 , the fifth valve group 25 , the sixth valve group 26 and the seventh valve group 27 includes a regulating valve and a shut-off valve.

[0066] In this embodiment, the speed load of the turbine 2 can be directly controlled by setting the seventh valve group 27 on the connecting trunk line between the reactor 1 and the turbine 2. The first valve group 21 to the seventh valve group 27 are all set in the form of regulating valves and stop valves. The regulating valve can control the mass of the working fluid flowing through the pipeline by the size of the opening to achieve linear regulation of the load or control the regulation degree, while the stop valve is used in fully open or fully closed scenarios to facilitate the adjustment operation; in addition, with the mutual cooperation of the regulating valves, different circulation paths can be formed to meet the adjustment needs of the power generation system under different working conditions.

[0067] In some embodiments, in order to realize the automation of load regulation of the power generation system, optionally, the power generation system also includes a PID control module, which is electrically connected to each valve group and is used to send corresponding adjustment signals according to the speed signal of the turbine 2, the load signal, temperature, pressure, and flow of the generator 3 to control the opening and closing of each valve group respectively.

[0068] The PID control module is an integrated unit module in which the PID algorithm program is written, which includes at least a speed PID control submodule and a load PID control submodule, and can be applied in the power generation system of the present application with the core control unit of the power generation system as the carrier. As a relatively mature existing technology, its principles and control implementation methods will not be described in detail here. This embodiment is intended to indicate that automatic, convenient and high-precision load control can be achieved by applying the PID control module to the power generation system of the present application.

[0069] In summary of the aforementioned embodiments, the power generation system of the present application can achieve quality control of the working fluid circulating in the system by means of the branch formed by the compressor bypass 11, the turbine bypass 12, and the storage tank 7 unit, through the form of diversion and confluence, thereby adjusting the quality of the circulating working fluid acting on the turbine 2 to adjust the load of the power generation system. Furthermore, by setting the first regenerator bypass 15 and the second regenerator bypass 16, the working fluid temperature at the inlet and outlet of the reactor 1 can be adjusted to assist in load regulation. The setting of the first valve group 21 to the seventh valve group 27 on each circulation trunk and branch and their form (shut-off valve and regulating valve) facilitate the control of the power generation system path and cooperate with the use of the PID control module to achieve automation and efficiency in the load regulation of the power generation system.

[0070] The following describes in detail the load regulation control method and principle that can be achieved by the adaptive load regulation system of this application:

[0071] 1. Volume control. The working principle of volume control is to adjust the system load by increasing or decreasing the mass of the working fluid in the loop. The control logic flow diagram is shown in Figure 3. The compressor 6 of the supercritical carbon dioxide cycle operates near the critical point, where the working fluid density is more sensitive to the influence of pressure and temperature. When the system needs to reduce the load, keep the third valve group 23 closed, open the stop valve of the fourth valve group 24, and adjust the flow through the regulating valve on the pipeline, so as to remove a part of the working fluid from the loop and enter the storage tank 7 for storage, thereby achieving load reduction operation; when the system needs to increase the load, keep the fourth valve group 24 closed, open the stop valve of the third valve group 23, and adjust the flow through the regulating valve on the pipeline, so that the storage tank 7 replenishes a part of the working fluid into the loop, thereby achieving load increase operation. The advantage of this control method is that there is no waste of working fluid energy during the load change process, the system efficiency can be maintained, and the adjustment rate is fast.

[0072] 2. Speed ​​Control. Speed ​​control achieves load variation by changing the turbomachinery speed, thereby varying the system flow and pressure. A schematic diagram of the control logic flow is shown in Figure 4. For a circulation system with a coaxial arrangement of compressor 6 and turbine 2, speed control can only achieve the same percentage change in the speeds of compressor 6 and turbine 2. That is, compressor 6 and turbine 2 operate at the same speed and are regulated together; independent speed changes are not possible. In this application, load regulation through speed control is primarily achieved via the seventh valve group 27. Considering equipment lifespan and speed regulation accuracy, this regulation method is unsuitable for applications with frequent load variations. Based on the coaxial arrangement of the equipment, this application proposes a speed-shifting control method. This method maintains a constant speed within a certain load range, with secondary load regulation achieved via the seventh valve group 27. If the load exceeds this load range, the speed shift is changed. When the system target load changes and crosses the speed step corresponding to the load range, variable speed control is implemented. At this time, the speed feedback channel and the load feedback channel are simultaneously activated. The speed feedback channel generates a target speed based on the load range-speed step curve. This speed difference is then compared with the measured speed value, and the speed PID control submodule generates a speed-dependent valve position control signal. The load feedback channel, on the other hand, compares the target load with the measured power value to generate a load difference. The load PID control submodule then generates a load-related valve position control signal. This signal, combined with the speed-related valve position control signal, acts on the regulating valve of the seventh valve group 27 to switch turbine speed gears and track changes in the target load. During load reduction control, when the load is reduced to a certain depth, compressor 6 may experience surge due to reduced inlet flow. At this point, the regulating valve opening of the first valve group 21 of the compressor bypass 11 can be increased to increase the inlet flow of compressor 6, ensuring normal and stable system operation.

[0073] 3. Throttling control. Throttling control is a means of achieving load regulation by changing the circuit pressure drop. The control logic flow diagram is shown in Figure 5. The power generation system of the present application adopts turbine 2 inlet throttling control, that is, it is achieved through the throttling of the seventh valve group 27 of the present application. When the opening of the regulating valve of the seventh valve group 27 decreases, the pressure drop at both ends of the valve increases. On the one hand, the expansion ratio and output power of turbine 2 decrease; on the other hand, the resistance of the entire system increases, the flow decreases, the pressure ratio of compressor 6 increases, and the outlet pressure of compressor 6 increases. At this time, it is necessary to prevent compressor 6 from entering the surge zone, and it is necessary to cooperate with the bypass control method to jointly adjust and increase the load reduction depth so that throttling and load reduction can continue. When the system needs to reduce the load, the opening of the regulating valve in the seventh valve group 27 at the inlet of turbine 2 is reduced to reduce the intake volume of turbine 2 and thus reduce the output power, thereby achieving the purpose of reducing the load. Conversely, the opening of the regulating valve in the seventh valve group 27 at the inlet of turbine 2 is increased. When the load is reduced to a certain depth, the compressor 6 will surge due to the reduction in inlet flow. At this time, the opening of the regulating valve of the first valve group 21 of the compressor bypass 11 should be increased to increase the inlet flow of compressor 6 so that the system can operate normally and stably.

[0074] 4. Bypass control. Bypass control is a means of achieving load regulation by changing the mass flow entering the compressor 6 or turbine 2. The control logic flow diagram is shown in Figure 6. The power generation system of the present application is provided with a compressor bypass 11 and a turbine bypass 12 to achieve load regulation. When the system needs to reduce the load, the opening of the regulating valve of the second valve group 22 of the turbine bypass 12 is increased to reduce the working fluid entering the turbine 2 to do work, thereby achieving the purpose of reducing the load. Conversely, the opening of the regulating valve of the second valve group 22 of the turbine bypass 12 is reduced. When the load is reduced to a certain depth, the compressor 6 will surge due to the reduction in the inlet flow. At this time, the opening of the regulating valve of the first valve group 21 of the compressor bypass 11 should be increased to increase the inlet flow of the compressor 6 so that the system can operate normally and stably.

[0075] In addition, the power generation system of the present application is also provided with a first regenerator bypass 15 and a second regenerator bypass 16. As shown in FIG7 , by adjusting the valve openings of the fifth valve group 25 and the sixth valve group 26 on the pipeline, the temperature of the working fluid at the inlet and outlet of reactor 1 is regulated, thereby changing the temperature of the working fluid at the inlet of turbine 2, changing the work produced by turbine 2, and achieving the purpose of load regulation. The power generation system of the present application is provided with the first regenerator bypass 15 and the second regenerator bypass 16 primarily to stabilize the inlet temperature of reactor 1 and prevent excessive fluctuations in the inlet and outlet temperatures of reactor 1 during rapid load changes, which could affect the life of the core material.

[0076] Any load regulation method that can be implemented by the power generation system of the present application as described above has its own advantages, disadvantages and limitations, and it is impossible to achieve load regulation within the entire operating range by adopting a single load regulation method. During the implementation of volume control, it is necessary to change the amount of carbon dioxide working fluid in the device. The wider the range of load adjustment, the greater the change in the amount of carbon dioxide working fluid in the device, and the greater the volume requirement for the storage tank 7. The high-pressure, large-volume storage tank 7 involves the processing and manufacturing of large forgings, which is not only extremely difficult to process, but also very expensive. Therefore, it is suitable for use in high-load ranges and small-range load changes. Load change is achieved through speed control. The speed control has the highest efficiency in the entire load change process, but considering the equipment life and speed regulation accuracy, this regulation method is not suitable for application scenarios with frequent load changes. The throttling control method and the bypass control method have low regulation efficiency and are not suitable for use in high-load ranges. They have the advantages of simplicity and speed when used at startup or in low-load ranges.

[0077] Therefore, the present application further provides an adaptive load regulation method to comprehensively apply the above-mentioned various load regulation methods to the power generation system of the aforementioned embodiment of the present application. Referring to FIG. 2 , the load regulation method includes:

[0078] Step S1, generating the adjustment signal based on the difference between the target load and the current load;

[0079] Step S2: Control the first valve group 21 to the seventh valve group 27 according to the adjustment signal to adjust the load of the power generation system.

[0080] Furthermore, the step of controlling the first valve group 21 to the seventh valve group 27 according to the adjustment signal to adjust the load of the power generation system includes:

[0081] When the current load is within the range of 90% to 100% of the full load of the power generation system, the opening and closing and the opening degree of the third valve group 23 and the fourth valve group 24 are controlled by the regulating signal to adjust the load of the power generation system;

[0082] When the current load is within a range of 40% to 90% of the full load of the power generation system, the opening of the seventh valve group 27 is controlled by the regulating signal to adjust the load of the power generation system;

[0083] When the current load is within a range of 20% to 40% of the full load of the power generation system, the openings of the first valve group 21 and the seventh valve group 27 are controlled by the adjustment signal to adjust the load of the power generation system;

[0084] When the current load is within the range of 0% to 20% of the full load of the power generation system, the openings of the first valve group 21 and the second valve group 22 are controlled by the regulating signal to adjust the load of the power generation system.

[0085] Specifically, with reference to the logical principle diagrams of Figures 3 to 7, in the process of applying this method to load regulation of the power generation system, it is necessary to obtain the target load, feed it back to the core control part of the power generation system and compare it with the current load, calculate the load difference, and then generate a corresponding regulation signal according to the load difference by the PID control module. The regulation signal is expressed in the form of segmentation, positive and negative directions, and each regulation signal can correspondingly control the opening and closing and opening degree of the first valve group 21 to the seventh valve group 27 to achieve comprehensive load regulation;

[0086] In the load regulation of all working conditions, this application makes the following arrangements for the load regulation mode and regulation section for the proposed power generation system:

[0087] In the full load range of 90% to 100% (including 90%), the volume control method is adopted. In this range, rapid adjustment can be achieved through the storage tank 7 and the bypass formed by it, without the need for a large-volume storage tank 7 design, which is beneficial to the overall design optimization of the power generation system.

[0088] In the full load range of 40% to 90% (inclusive), the speed control method is adopted. In this range, frequent load adjustment is not required. By controlling the mechanical speed of turbine 2 and using the seventh valve group 27 to control the amount of working fluid transferred between reactor 1 and turbine 2, the equipment life can be extended and the adjustment is efficient.

[0089] In the full load range of 20% to 40% (including 20%), the throttling + bypass control method is adopted. The load of the power generation system in this range is in a relatively low state, and the load regulation degree is smaller or the accuracy requirement is higher. Therefore, the load is adjusted with the help of the cooperation of the seventh valve group 27 and the first valve group 21. When the load is reduced to a certain extent and the compressor 6 surges due to the reduction in inlet flow, the regulating valve of the first valve group 21 of the compressor bypass 11 is opened to increase the inlet flow of the compressor 6, so that the system can operate normally and stably.

[0090] Therefore, in some embodiments, when the current load is within a range of 20% to 40% of the full load of the power generation system, the step of adjusting the load of the power generation system by controlling the openings of the first valve group 21 and the seventh valve group 27 by the adjustment signal includes:

[0091] closing the seventh valve group 27 or reducing the opening of the seventh valve group 27;

[0092] Determining whether the compressor 6 experiences surge;

[0093] If so, open the first valve group 21 or increase the opening of the first valve group 21.

[0094] In the full load range of 0% to 20%, the bypass control method is adopted. The load of the power generation system in this range is at a very low state, and the accuracy of load regulation is required to be higher. Therefore, the working medium in the circulation trunk is slightly adjusted with the help of the compressor bypass 11 and the turbine bypass 12, that is, the load is adjusted with the help of the second valve group 22. When the load is reduced to a certain level and the compressor 6 surges due to the reduction in inlet flow, the regulating valve of the first valve group 21 of the compressor bypass 11 is opened to increase the inlet flow of the compressor 6, so that the system can operate normally and stably.

[0095] Therefore, in some embodiments, when the current load is within the range of 0% to 20% of the full load of the power generation system, the step of adjusting the load of the power generation system by controlling the openings of the first valve group 21 and the second valve group 22 by the adjustment signal includes:

[0096] Open the second valve group 22 or increase the opening of the second valve group 22;

[0097] Determining whether the compressor 6 experiences surge;

[0098] If so, open the first valve group 21 or increase the opening of the first valve group 21.

[0099] In some other embodiments, after the step of adjusting the load of the power generation system by controlling the first valve group 21 to the seventh valve group 27 according to the adjustment signal, the following steps are included:

[0100] Determining whether the inlet temperature and the outlet temperature of the reactor 1 are within a preset range;

[0101] If not, the inlet temperature and outlet temperature of the reactor 1 are adjusted through the fifth valve group 25 and the sixth valve group 26 .

[0102] In this embodiment, temperature control is achieved during the load regulation process of the power generation system through the first bypass 15 and the second bypass 16 of the regenerator. The PID control module may further include a temperature PID control submodule to achieve temperature feedback and regulation signal generation of the power generation system under the current temperature working conditions, thereby regulating the temperature of the inlet and outlet of the reactor 1 through the fifth valve group 25 and the sixth valve group 26.

[0103] The adaptive load regulation method provided in the present application is applied to a power generation system with a load regulation function. On the basis of fully considering the characteristics of the working medium and combining the structure of the power generation system, it can avoid the shortcomings and limitations of a single load regulation means, combine the characteristics of different regulation means, and then propose a load regulation means within the full operating range. The bypasses cooperate with each other to form a load regulation method that adaptively matches the regulation means according to different power regulation ranges, thereby achieving the effect of improving the system power generation efficiency, stabilizing system parameters, and quickly regulating the load.

[0104] The above detailed description of the specific implementation methods of the application is intended only as an example, and the present application is not limited to the specific implementation methods described above. For those skilled in the art, any equivalent modifications or substitutions made to the application are also within the scope of the present application. Therefore, equivalent changes, modifications, and improvements made without departing from the spirit and scope of the present application should be included within the scope of the present application.

Claims

1. A power generation system with load regulation function, wherein: The power generation system includes a reactor, a turbine, a regenerator, a cooler, and a compressor through which a power generation medium flows in sequence. The power generation medium returns to the reactor from the outlet of the compressor through the regenerator to form a cycle in the power generation system. The output end of the turbine is connected to a generator. The compressor, the turbine, and the generator are coaxially arranged. as well as, a compressor bypass, the compressor bypass connecting the outlet of the compressor and the inlet of the cooler, the compressor bypass being provided with a first valve group; a turbine bypass, the turbine bypass connecting the inlet of the turbine and the outlet of the turbine, the turbine bypass being provided with a second valve group; The power generation system further includes a storage tank; The outlet of the storage tank is connected to the inlet of the cooler to form a first bypass of the storage tank, and the first bypass of the storage tank is provided with a third valve group; The storage tank inlet is connected to the compressor outlet to form a second storage tank bypass, and the second storage tank bypass is provided with a fourth valve group.

2. The power generation system with load regulation function according to claim 1, wherein: The power generation system further comprises: a first bypass of the regenerator, the first bypass of the regenerator connecting the outlet of the compressor and the inlet of the reactor, and the first bypass of the regenerator being provided with a fifth valve group; The second bypass of the regenerator is connected to the outlet of the turbine and the inlet of the reactor, and the second bypass of the regenerator is provided with a sixth valve group.

3. The power generation system with load regulation function according to claim 2, wherein: A seventh valve group is provided on the connecting trunk line between the reactor and the turbine.

4. The power generation system with load regulation function according to claim 3, wherein: The first valve group, the second valve group, the third valve group, the fourth valve group, the fifth valve group, the sixth valve group, and the seventh valve group all include regulating valves and shut-off valves.

5. The power generation system with load regulation function according to claim 4, wherein: The power generation system also includes a PID control module, which is electrically connected to each valve group. The PID control module is used to issue corresponding adjustment signals based on the speed signal of the turbine and the load signal, temperature, pressure, and flow of the generator to control the opening and closing of each valve group respectively.

6. An adaptive load regulation method, wherein: The load regulation method is applied to the power generation system with load regulation function as claimed in claim 5, and the load regulation method includes: generating a regulating signal based on a difference between the target load and the current load; The first to seventh valve groups are controlled according to the adjustment signal to adjust the load of the power generation system.

7. The adaptive load regulation method according to claim 6, wherein: The step of controlling the first to seventh valve groups according to the adjustment signal to adjust the load of the power generation system includes: When the current load is within the range of 90% to 100% of the full load of the power generation system, The regulating signal controls the opening and closing and the opening degree of the third valve group and the fourth valve group to adjust the load of the power generation system; When the current load is within a range of 40% to 90% of the full load of the power generation system, controlling the opening of the seventh valve group by the adjustment signal to adjust the load of the power generation system; When the current load is within a range of 20% to 40% of the full load of the power generation system, controlling the openings of the first valve group and the seventh valve group by the adjustment signal to adjust the load of the power generation system; When the current load is within the range of 0% to 20% of the full load of the power generation system, the openings of the first valve group and the second valve group are controlled by the adjustment signal to adjust the load of the power generation system.

8. The adaptive load regulation method according to claim 7, wherein: After the step of controlling the first to seventh valve groups according to the adjustment signal to adjust the load of the power generation system, the method further includes: Determining whether the inlet temperature and the outlet temperature of the reactor are both within a preset range; If the inlet temperature and the outlet temperature of the reactor are both outside the preset range, the inlet temperature and the outlet temperature of the reactor are adjusted by the fifth valve group and the sixth valve group.

9. The adaptive load regulation method according to claim 7, wherein: The step of controlling the openings of the first valve group and the second valve group by the adjustment signal to adjust the load of the power generation system when the current load is within the range of 0% to 20% of the full load of the power generation system includes: opening the second valve group or increasing the opening of the second valve group according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload; determining whether surge occurs in the compressor; If so, open the first valve group or increase the opening of the first valve group.

10. The adaptive load regulation method according to claim 7, wherein: The step of controlling the openings of the first valve group and the seventh valve group by the adjustment signal to adjust the load of the power generation system when the current load is within a range of 20% to 40% of the full load of the power generation system includes: closing the seventh valve group or reducing the opening of the seventh valve group according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload; determining whether surge occurs in the compressor; If so, open the first valve group or increase the opening of the first valve group.

11. The adaptive load regulation method according to claim 7, wherein: The step of controlling the opening of the seventh valve group by the adjustment signal to adjust the load of the power generation system when the current load is within the range of 40% to 90% of the full load of the power generation system comprises: The opening of the seventh valve group is reduced according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload.

12. The adaptive load regulation method according to claim 7, wherein: The step of controlling the opening and closing and the opening degree of the third valve group and the fourth valve group by the adjustment signal to adjust the load of the power generation system when the current load is within the range of 90% to 100% of the full load of the power generation system includes: The third valve group is closed and the fourth valve group is opened or the opening of the fourth valve group is increased according to the regulating signal; wherein the regulating instruction of the regulating signal is to reduce the system workload.

Images