Phase modulation type fused salt Carnot battery system integrated with synchronous clutch and operation method

Abstract

The invention discloses a phase modulation type fused salt Carnot battery system integrated with a synchronous clutch and an operation method. The system comprises an electric heater, one end of the electric heater is connected with a high-temperature heat storage tank, the other end of the electric heater is connected with a low-temperature heat storage tank, one end of the high-temperature heat storage tank is connected with a superheater, and the other end of the high-temperature heat storage tank is connected with a reheater; one end of the superheater is connected with a steam generator, the other end of the superheater is connected with a high-pressure cylinder, one end of the steam generator is connected with a steam pocket, and the other end is connected with a preheater; one end of the high-pressure cylinder is connected with a medium-low pressure cylinder, the other end of the high-pressure cylinder is connected with a high-pressure heater, the medium-low pressure cylinder is connected with a synchronous motor through an SSS clutch, one end of the high-pressure heater is connected with a deaerator, and the other end of the high-pressure heater is connected with a preheater; and one end of the deaerator is connected with the medium-low pressure cylinder, and the other end of the deaerator is connected with the low-pressure heater, so that the Carnot battery system has a phase modulation function, and has important significance for stable operation of a power grid and improvement of electric energy quality.

Description

Technical Field

[0001] The present invention belongs to the technical field of generator sets, and in particular relates to a phase-modulated molten salt Carnot battery system with an integrated synchronous clutch and an operation method thereof. Background Art

[0002] With the rapid development of renewable energy power generation, problems such as low inertia, overvoltage, and broadband oscillation of high-proportion renewable energy are prominent, hindering the expansion of renewable energy power generation. Compared with conventional generators, renewable energy generators are insufficient in anti-interference, overload capacity, and frequency and voltage regulation. When a system fails and the frequency and voltage fluctuate greatly, it is easy to cause the renewable energy generator to be disconnected from the grid, which has an adverse effect on the safe and stable operation of the system. The phase regulator runs in parallel with the power grid and is located on the AC side of the AC to DC and DC to AC. When the power grid system fails, the phase regulator is not affected by the power grid system. It has strong instantaneous reactive power support and short-term overload capacity. It has unique advantages in dynamic reactive power compensation and can provide rotational inertia support for the power grid. However, the construction of independent phase regulators is often costly, resulting in the Carnot battery having power generation and energy storage, but not having phase modulation function, which affects production. Summary of the invention

[0003] The purpose of the present invention is to provide a phase-adjustable molten salt Carnot battery system and an operating method with an integrated synchronous clutch, so as to solve the technical defect that the Carnot battery in the prior art has the function of power generation and energy storage but does not have the phase-adjusting function, which affects the production.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: In a first aspect, a phase-modulating molten salt Carnot battery system with an integrated synchronous clutch is provided, comprising an electric heater, one end of the electric heater is connected to a high-temperature heat storage tank, and the other end is connected to a low-temperature heat storage tank, one end of the high-temperature heat storage tank is connected to a superheater, and the other end is connected to a reheater; one end of the superheater is connected to a steam generator, and the other end is connected to a high-pressure cylinder, one end of the steam generator is connected to a steam drum, and the other end is connected to a preheater; One end of the high-pressure cylinder is connected to the medium- and low-pressure cylinders, and the other end is connected to the high-pressure heater. The medium- and low-pressure cylinders are connected to the synchronous motor through the SSS clutch. One end of the high-pressure heater is connected to the deaerator, and the other end is connected to the preheater; one end of the deaerator is connected to the medium- and low-pressure cylinders, and the other end is connected to the low-pressure heater. One end of the low-pressure heater is also connected to the medium- and low-pressure cylinders, and the other end is connected to the condenser, and the condenser is connected to the medium- and low-pressure cylinders.

[0005] In a second aspect, a method for operating a phase-adjusting molten salt Carnot battery system with an integrated synchronous clutch is provided, which, when switching from power generation to phase adjustment operation, comprises: Reduce the molten salt flow at the outlet of the high-temperature heat storage tank and the amount of steam generated by the steam generator to reduce the load to between 10% and 15% of the rated load; Reduce the load of the high-pressure cylinder, medium- and low-pressure cylinders and steam generators to 10% of the rated load; The preheater and steam generator stop running, the steam generation system stops supplying water, the saturated steam stored in the drum enters the superheater, and after being heated by the molten salt in the superheater, it is used to supply gas to the high-pressure cylinder. The molten salt in the superheater releases heat and flows back to the high-temperature heat storage tank; Continue to reduce the load of the high-pressure cylinder and the medium- and low-pressure cylinders from 10% of the rated load until the power is reduced to zero; By means of excitation control, the synchronous motor is switched from a power generation mode to a motoring mode, and active power is absorbed through the power grid so that the speed of the synchronous motor is maintained at 3000 r / min; Reduce the speed of the high-pressure cylinder and the medium- and low-pressure cylinders to below 2950~2980 r / min and maintain it unchanged, separate the shaft system connecting the high-pressure cylinder and the medium- and low-pressure cylinders to the synchronous motor, so that the synchronous motor absorbs active power from the power grid and enters the phase modulation mode.

[0006] Furthermore, when the loads of the high-pressure cylinder, the medium- and low-pressure cylinders and the steam generator are reduced to 10% of the rated load, the method further includes: The excess steam produced by the steam generator is sent to the condenser through the bypass of the high-pressure cylinder and the medium- and low-pressure cylinders.

[0007] Furthermore, the load of the high pressure cylinder and the medium and low pressure cylinders is further reduced from 10% of the rated load until the power is reduced to zero, further comprising: The steam drum delivers steam to the high pressure cylinder and the medium and low pressure cylinders.

[0008] Furthermore, after entering the phase modulation mode, the method further includes: Reduce the speed of the high-pressure cylinder and the medium- and low-pressure cylinders to 200 r / min, introduce a small amount of steam into the high-pressure cylinder and the medium- and low-pressure cylinders to maintain idling, and enter hot standby state.

[0009] Furthermore, when switching from phase adjustment to power generation, it includes: The high-temperature molten salt in the high-temperature heat storage tank is sent into the steam generation system to preheat the equipment and make the superheater generate superheated steam; Using the superheated steam generated by the superheater to warm up the high pressure cylinder and the intermediate and low pressure cylinders, so that the rotation speeds of the high pressure cylinder and the intermediate and low pressure cylinders increase to 3000 r / min; Increase the speed of the high-pressure cylinder and the medium- and low-pressure cylinders to 3000~3010r / min, engage the SSS clutch, and the high-pressure cylinder and the medium- and low-pressure cylinders transmit power to the synchronous motor to switch the synchronous motor from the motor state to the generator state.

[0010] Furthermore, after the synchronous motor is switched from the motor state to the generator state, the method further comprises: The shaft systems of the high-pressure cylinder and the medium- and low-pressure cylinders are connected to the shaft system of the synchronous motor to maintain the rotation speed of the high-pressure cylinder and the medium- and low-pressure cylinders at 3000r / min.

[0011] Furthermore, when switching from power generation to shutdown operation, it includes: Reduce the molten salt flow at the outlet of the high-temperature heat storage tank and the amount of steam generated by the steam generator to reduce the load to between 10% and 15% of the rated load; The preheater and steam generator stop running, the steam generation system stops supplying water, the saturated steam stored in the drum enters the superheater, and after being heated by the molten salt in the superheater, it is used to supply gas to the high-pressure cylinder. The molten salt in the superheater releases heat and flows back to the high-temperature heat storage tank; Continue to reduce the load of the high-pressure cylinder and the medium- and low-pressure cylinders from 10% of the rated load until the main steam valve is closed, and interlock the synchronous motor to disconnect from the grid; Turn on the SSS clutch self-locking function so that the high-pressure cylinder and the medium- and low-pressure cylinders can reduce the speed to stop synchronously with the SSS clutch.

[0012] Further, after the SSS clutch synchronously reduces the speed to stop, the SSS clutch is still in the engaged state.

[0013] Furthermore, when switching from shutdown to power generation, it includes: The molten salt in the high-temperature heat storage tank is sent to the superheater, the regenerator, the steam generator and the preheater for preheating, and the flow rate of the molten salt working medium at the outlet of the high-temperature heat storage tank is increased so that the amount of steam generated by the superheater and the reheater is gradually increased; The high pressure cylinder and the medium and low pressure cylinders are operated at a cranking speed, so that a speed difference is generated between the medium and low pressure cylinders and the synchronous motor, so that the SSS clutch is merged; The high-pressure cylinder and the medium- and low-pressure cylinders are connected to the synchronous motor, and warm-up, impulse running, speed increase, grid connection and load increase are performed in sequence. During the warm-up, impulse running, speed increase, grid connection and load increase, the SSS clutch is in the engaged state.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The electric heater converts electrical energy into thermal energy and stores it in a high-temperature heat storage tank. Then, through a series of heat energy conversion processes, the thermal energy is efficiently converted into mechanical energy, and then converted into electrical energy by the synchronous motor, which significantly improves the energy conversion efficiency of the entire system. Secondly, the system integrates a synchronous clutch, which allows the working state of the motor to be quickly adjusted when needed, and has a phase adjustment function, which is of great significance for the stable operation of the power grid and the improvement of power quality. At the same time, the high-temperature heat storage tank and the low-temperature heat storage tank provide powerful energy storage capacity, which can store thermal energy when the power demand is low and release it during peak hours to meet the power supply demand, enhancing the flexibility and reliability of the system.

[0015] 2. By providing an operating method, the Carnot battery can be used to flexibly switch between power generation, energy storage or phase adjustment according to changes in the power grid system, thereby improving the practicality of the Carnot battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic diagram of a phase-modulating molten salt Carnot battery system with an integrated synchronous clutch provided by the present invention; In the figure: 1. Electric heater; 2. High-temperature heat storage tank; 3. Superheater; 4. Reheater; 5. Steam generator; 6. Steam drum; 7. High-pressure cylinder; 8. Medium and low-pressure cylinders; 9. SSS clutch; 10. Synchronous motor; 11. Condenser; 12. Low-pressure heater; 13. Deaerator; 14. High-pressure heater; 15. Preheater; 16. Low-temperature heat storage tank. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0021] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0022] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0023] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] With the rapid development of renewable energy power generation, problems such as low inertia, overvoltage, and broadband oscillation of high-proportion renewable energy are prominent, hindering the expansion of renewable energy power generation. Compared with conventional generators, renewable energy generators are insufficient in anti-interference, overload capacity, and frequency and voltage regulation. When a system fails and the frequency and voltage fluctuate greatly, it is easy to cause the renewable energy generator to be disconnected from the grid, which has an adverse effect on the safe and stable operation of the system. The phase regulator runs in parallel with the power grid and is located on the AC side of the AC to DC and DC to AC. When the power grid system fails, the phase regulator is not affected by the power grid system. It has strong instantaneous reactive power support and short-term overload capacity. It has unique advantages in dynamic reactive power compensation and can provide rotational inertia support for the power grid. However, the construction of independent phase regulators is often costly, resulting in the Carnot battery having power generation and energy storage, but not having phase modulation function, which affects production.

[0025] In order to solve the above-mentioned defects of the prior art, the inventor provides a phase-modulated molten salt Carnot battery system with an integrated synchronous clutch and an operation method.

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings: First, as Figure 1As shown, an embodiment of the present invention provides a phase-adjustable molten salt Carnot battery system with an integrated synchronous clutch, the system comprising an electric heater 1, one end of the electric heater 1 is connected to a high-temperature heat storage tank 2, and the other end is connected to a low-temperature heat storage tank 16. The electric heater 1 converts electrical energy into thermal energy and transfers the heat to the molten salt in the high-temperature heat storage tank 2, thereby realizing the centralized and efficient conversion of thermal energy and reducing the loss in the energy conversion process. The high-temperature heat storage tank 2 can store a large amount of thermal energy and release the thermal energy to the system or external equipment through heat exchange and other methods when needed, thereby improving the flexibility and reliability of energy utilization. The electric heater 1 is installed between the high-temperature heat storage tank 2 and the low-temperature heat storage tank 16, so that a temperature gradient is formed between the high-temperature heat storage tank 2 and the low-temperature heat storage tank 16, which can realize multi-stage utilization and step-by-step recovery of thermal energy, further improving energy utilization efficiency. One end of the high-temperature heat storage tank 2 is connected to the superheater 3, and the other end is connected to the reheater 4. One end of the superheater 3 is connected to the steam generator 5, and the other end is connected to the high-pressure cylinder 7. One end of the steam generator 5 is connected to the drum 6, and the other end is connected to the preheater 15. The drum 6 is also connected to the superheater 3 and the steam generator 5. While one end of the reheater 4 is connected to the high-pressure cylinder 7, the superheater 3 is also connected to the high-pressure cylinder 7. One end of the high-pressure cylinder 7 is connected to the medium-low pressure cylinder 8, and the other end is connected to the high-pressure cylinder 7. Heater 14, medium and low pressure cylinder 8 are connected to synchronous motor 10 through SSS clutch 9; one end of high pressure heater 14 is connected to deaerator 13, and the other end is connected to preheater 15, and preheater 15 is connected to steam drum 6 and low temperature heat storage tank 16; one end of deaerator 13 is connected to medium and low pressure cylinder 8, and the other end is connected to low pressure heater 12, one end of low pressure heater 12 is also connected to medium and low pressure cylinder 8, and the other end is connected to condenser 11, and condenser 11 is connected to medium and low pressure cylinder 8. Electric energy is converted into heat energy through electric heater 1 and stored in high temperature heat storage tank 2, and then through a series of heat energy conversion processes, heat energy is finally efficiently converted into mechanical energy, and then converted into electric energy by synchronous motor 10, so that the energy conversion efficiency of the whole system is significantly improved. Secondly, the system integrates a synchronous clutch, which allows the working state of the motor to be quickly adjusted when needed, and has a phase adjustment function, which is of great significance to the stable operation of the power grid and the improvement of power quality. At the same time, the high-temperature heat storage tank 2 and the low-temperature heat storage tank 16 provide powerful energy storage capabilities, which can store heat energy when electricity demand is low and release it during peak hours to meet power supply needs, thereby enhancing the flexibility and reliability of the system.

[0027] In a second aspect, a method for operating a phase-adjusting molten salt Carnot battery system with an integrated synchronous clutch is provided, which, when switching from power generation to phase adjustment operation, comprises: The molten salt flow rate in the outlet of the high-temperature heat storage tank 2 and the amount of steam generated by the steam generator 5 are reduced to reduce the load to between 10% and 15% of the rated load, and then the load of the high-pressure cylinder 7, the medium- and low-pressure cylinders 8 and the steam generator 5 are reduced to 10% of the rated load, thereby avoiding the impact of the rapid change in load on the stability of the system; in this process, the excess steam generated by the steam generator 5 is sent to the condenser 11 through the bypass of the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8, thereby effectively managing the steam flow rate and temperature in the system and ensuring the smoothness of the switching process. The preheater 15 and the steam generator 5 are stopped, and the water supply to the steam generation system (superheater 3, reheater 4, steam generator 5 and preheater 15) is stopped. The saturated steam stored in the drum 6 enters the superheater 3, and after being heated by the molten salt in the superheater 3, it is used to supply gas to the high-pressure cylinder 7. The molten salt in the superheater 3 releases heat and flows back to the high-temperature heat storage tank 2; when the preheater 15 and the steam generator 5 are stopped, the saturated steam stored in the drum 6 is used to avoid the waste of these steam due to system shutdown. These steam are further heated into superheated steam by the molten salt in the superheater 3, which improves the work capacity of the steam, thereby realizing the efficient use of thermal energy. In addition, heating the steam with the molten salt in the superheater 3 not only improves the quality of the steam, but also makes the temperature and pressure of the steam more stable, which helps to maintain the stable operation of the high-pressure cylinder 7 and other equipment, thereby enhancing the stability of the entire system. In addition, the molten salt in the superheater 3 flows back to the high-temperature heat storage tank 2 after releasing heat. This process realizes the closed-loop management of thermal energy. The high-temperature heat storage tank 2, as a thermal energy storage device, can release thermal energy when needed, provide a stable heat source for the system, and reduce energy waste.

[0028] The load of the high-pressure cylinder 7 and the medium- and low-pressure cylinder 8 is further reduced from 10% of the rated load until the power is reduced to zero, which ensures a smooth transition of the system load and avoids system vibration or instability that may be caused by a sharp change in load. In this process, the drum 6 delivers steam to the high-pressure cylinder 7 and the medium- and low-pressure cylinder 8, ensuring the continuity of steam supply during the load reduction process. Secondly, through excitation control, the synchronous motor 10 is switched from the power generation mode to the electric mode, and the active power is absorbed through the power grid, which helps to stabilize the voltage and frequency of the power grid and improve the power quality of the power grid. In particular, when the power grid requires reactive power compensation or balance, the phase modulation function of the synchronous motor 10 can play an important role and enhance the stability and reliability of the power grid. In addition, the speed of the synchronous motor 10 is maintained at 3000 r / min, and then the speed of the high-pressure cylinder 7 and the medium- and low-pressure cylinder 8 is reduced to below 2950~2980 r / min and maintained unchanged, which helps to reduce mechanical shock and stress. Gradually reducing the speed can make the system transition to a new working state more smoothly and avoid damage to the equipment caused by sudden load changes or speed changes. The shaft system connecting the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 to the synchronous motor 10 is separated so that the synchronous motor 10 absorbs active power from the power grid and enters the phase adjustment mode, and the speed of the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 is reduced to 200 r / min, and a small amount of steam is introduced into the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 to maintain idling, and enter the hot standby state. Through the separation of the shaft system, the synchronous motor 10 can operate independently of the steam turbine system, and realize the rapid switching from the power generation mode to the phase adjustment mode, so that the system can be adjusted according to the power grid demand or operation strategy, and improve the adaptability and response speed of the system. The high-pressure cylinder 7 and the medium-low-pressure cylinder 8 are maintained in a low-speed idling state, and a small amount of steam is introduced to keep the system hot and ready. When a quick start or load increase is required, the system can respond quickly, shorten the start-up time and reduce the energy loss during the start-up process.

[0029] When switching from phase adjustment to power generation, the high-temperature molten salt in the high-temperature heat storage tank 2 is sent to the steam generation system (superheater 3, reheater 4, steam generator 5 and preheater 15) to preheat the equipment and make the superheater 3 generate superheated steam; by using the high-temperature molten salt in the high-temperature heat storage tank 2 to preheat the steam generation system, the startup time of the system can be significantly shortened. Compared with starting from a cold state, the system after preheating can reach the rated operating condition faster, improving the response speed of the system. During the preheating process, the various components of the steam generation system gradually reach the operating temperature, reducing the thermal stress and thermal deformation caused by temperature differences, and improving the startup efficiency and stability of the system. Secondly, the superheated steam generated by the superheater 3 is used to warm up the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8. The superheated steam can evenly heat the internal components of the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8, avoiding the concentration of thermal stress caused by uneven temperature, and helping to reduce the deformation or damage of the components caused by thermal stress. Through the warm-up process, the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8 can gradually reach the operating temperature, reducing the mechanical stress impact that may be caused by direct startup from a cold or low-temperature state, and helping to extend the service life of the equipment. When the temperature inside the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8 reaches the set temperature, the speed of the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8 is increased to 3000r / min, ensuring that the components start to run at high speed in a uniform and stable state, helping to reduce the thermal and mechanical stresses caused by temperature gradients or rapid temperature changes, and protecting the equipment from damage. Subsequently, the speed of the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 is increased to 3000~3010r / min, the SSS clutch 9 is engaged, and the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 transmit power to the synchronous motor 10 to switch the synchronous motor 10 from the motor state to the generator state. Finally, the shaft system of the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 is connected to the shaft system of the synchronous motor 10 to maintain the speed of the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 at 3000r / min. In this state, the mechanical efficiency and thermal efficiency of the turbine reach a relatively high level, which is beneficial to improving the power generation performance and economic benefits.

[0030] When switching from shutdown to power generation, the molten salt in the high-temperature heat storage tank 2 is sent to the superheater 3, reheater 4, steam generator 5 and preheater 15 for preheating, and the molten salt working medium flow rate at the outlet of the high-temperature heat storage tank 2 is increased, so that the amount of steam generated by the superheater 3 and the reheater 4 gradually increases; then the high-pressure cylinder 7 and the medium-low pressure cylinder 8 are operated at the cranking speed, so that the medium-low pressure cylinder 8 and the synchronous motor 10 have a speed difference, so that the SSS clutch 9 merges. Preheating the steam generation system with the molten salt in the high-temperature heat storage tank 2 can significantly improve the startup speed of the system. During the preheating process, each component gradually heats up, reducing the transition time from cold to hot, so that the system can reach a stable operating state faster. Increasing the flow rate of the molten salt working medium at the outlet of the high-temperature heat storage tank 2 can ensure that the superheater 3 and the reheater 4 obtain enough heat to generate more steam. The increase in steam production provides a sufficient power source for the subsequent power generation process, which helps to improve power generation efficiency and stability. Secondly, the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 are connected to the synchronous motor 10, and the five stages of warm-up, start-up, speed increase, grid connection and load increase are carried out in sequence. During the five stages of warm-up, start-up, speed increase, grid connection and load increase, the SSS clutch 9 is in the meshing state, ensuring the continuous power transmission between the high-pressure cylinder 7 and the medium-low-pressure cylinder 8 and the synchronous motor 10, reducing the system instability caused by power interruption or fluctuation; secondly, through continuous power transmission, the system can transition from one stage to another more smoothly. For example, in the warm-up stage, continuous power input helps the internal temperature of the cylinder body to rise evenly; in the start-up and speed increase stages, continuous power support helps to reduce speed fluctuations and mechanical stress.

[0031] When switching from power generation to shutdown, the molten salt flow rate at the outlet of the high-temperature heat storage tank 2 and the amount of steam generated by the steam generator 5 are reduced to reduce the load to between 10% and 15% of the rated load. At the same time, during this process, the excess steam generated by the steam generator 5 is sent to the condenser 11 from the bypass of the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8; when the preheater 15 and the steam generator 5 stop running, the steam generation system (superheater 3, reheater 4, steam generator 5 and preheater 15) stops supplying water, and the saturated steam stored in the drum 6 enters the superheater 3. , after being heated by the molten salt in the superheater 3, it is used to supply gas to the high-pressure cylinder 7. The molten salt in the superheater 3 releases heat and flows back to the high-temperature heat storage tank 2; then the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8 continue to reduce the load from 10% of the rated load until the main steam valve is closed, and the synchronous motor 10 is interlocked to go off the grid. In this process, the steam of the high-pressure cylinder 7 and the medium- and low-pressure cylinders 8 comes from the steam stored in the drum 6. By gradually reducing the load, the system can flexibly adapt to changes in grid demand, maintain stable operation of the grid, and reduce grid problems caused by load fluctuations. When it is necessary to quickly reduce the power generation output, the system can quickly adjust the load, close the main steam valve, and interlock the synchronous motor 10 to go off the grid. This rapid response capability helps to improve the safety and reliability of the system. Finally, the self-locking function of the SSS clutch 9 is turned on, so that the high-pressure cylinder 7 and the medium-low pressure cylinder 8 can reduce the speed synchronously with the SSS clutch 9 to stop. After the SSS clutch 9 reduces the speed synchronously to stop, the SSS clutch 9 is still in the meshing state. When the SSS clutch 9 remains in the meshing state, even if the system is in the shutdown state, it can prevent accidental start-up due to misoperation or other reasons. This improves the reliability and safety of the system.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

Claims

1. A phase-modulating molten salt Carnot battery system with integrated synchronous clutch, characterized in that: The electric heater (1) comprises one end of the electric heater (1) connected to a high-temperature heat storage tank (2) and the other end of the electric heater (1) connected to a low-temperature heat storage tank (16); one end of the high-temperature heat storage tank (2) is connected to a superheater (3) and the other end of the electric heater (1) is connected to a reheater (4); one end of the superheater (3) is connected to a steam generator (5) and the other end of the superheater (3) is connected to a high-pressure cylinder (7); one end of the steam generator (5) is connected to a steam drum (6) and the other end of the steam generator (5) is connected to a preheater (15); One end of the high-pressure cylinder (7) is connected to the medium- and low-pressure cylinders (8), and the other end is connected to the high-pressure heater (14); the medium- and low-pressure cylinders (8) are connected to the synchronous motor (10) via the SSS clutch (9); one end of the high-pressure heater (14) is connected to the deaerator (13), and the other end is connected to the preheater (15); one end of the deaerator (13) is connected to the medium- and low-pressure cylinders (8), and the other end is connected to the low-pressure heater (12); one end of the low-pressure heater (12) is also connected to the medium- and low-pressure cylinders (8), and the other end is connected to the condenser (11); the condenser (11) is connected to the medium- and low-pressure cylinders (8).

2. A method for operating a phase-modulated molten salt Carnot battery system with an integrated synchronous clutch, characterized in that: When switching from power generation to phase adjustment, it includes: Reduce the molten salt flow at the outlet of the high-temperature heat storage tank and the amount of steam generated by the steam generator to reduce the load to between 10% and 15% of the rated load; Reduce the load of the high-pressure cylinder, medium- and low-pressure cylinders and steam generators to 10% of the rated load; The preheater and steam generator stop running, the steam generation system stops supplying water, the saturated steam stored in the drum enters the superheater, and after being heated by the molten salt in the superheater, it is used to supply gas to the high-pressure cylinder. The molten salt in the superheater releases heat and flows back to the high-temperature heat storage tank; Continue to reduce the load of the high-pressure cylinder and the medium- and low-pressure cylinders from 10% of the rated load until the power is reduced to zero; By means of excitation control, the synchronous motor is switched from a power generation mode to a motoring mode, and active power is absorbed through the power grid so that the speed of the synchronous motor is maintained at 3000 r / min; Reduce the speed of the high-pressure cylinder and the medium- and low-pressure cylinders to below 2950~2980 r / min and maintain it unchanged, separate the shaft system connecting the high-pressure cylinder and the medium- and low-pressure cylinders to the synchronous motor, so that the synchronous motor absorbs active power from the power grid and enters the phase modulation mode.

3. The operating method according to claim 2, characterized in that: When the loads of the high pressure cylinder, the intermediate and low pressure cylinders and the steam generator are reduced to 10% of the rated load, the method further includes: The excess steam produced by the steam generator is sent to the condenser through the bypass of the high-pressure cylinder and the medium- and low-pressure cylinders.

4. The operating method according to claim 2, characterized in that: The high pressure cylinder and the medium and low pressure cylinders continue to reduce the load from 10% of the rated load until the power is reduced to zero, and further includes: The steam drum delivers steam to the high pressure cylinder and the medium and low pressure cylinders.

5. The operating method according to claim 2, characterized in that: After entering the phase modulation mode, the method further includes: Reduce the speed of the high-pressure cylinder and the medium- and low-pressure cylinders to 200 r / min, introduce a small amount of steam into the high-pressure cylinder and the medium- and low-pressure cylinders to maintain idling, and enter hot standby state.

6. The operating method according to claim 2, characterized in that: When switching from phase modulation to power generation, it includes: The high-temperature molten salt in the high-temperature heat storage tank is sent into the steam generation system to preheat the equipment and make the superheater generate superheated steam; Using the superheated steam generated by the superheater to warm up the high pressure cylinder and the intermediate and low pressure cylinders, so that the rotation speeds of the high pressure cylinder and the intermediate and low pressure cylinders increase to 3000 r / min; Increase the speed of the high-pressure cylinder and the medium- and low-pressure cylinders to 3000~3010r / min, engage the SSS clutch, and the high-pressure cylinder and the medium- and low-pressure cylinders transmit power to the synchronous motor to switch the synchronous motor from the motor state to the generator state.

7. The operating method according to claim 6, characterized in that: After the synchronous motor is switched from the motor state to the generator state, the method further comprises: The shaft systems of the high-pressure cylinder and the medium- and low-pressure cylinders are connected to the shaft system of the synchronous motor to maintain the rotation speed of the high-pressure cylinder and the medium- and low-pressure cylinders at 3000r / min.

8. The operating method according to claim 2, characterized in that: When switching from power generation to shutdown, including: Reduce the molten salt flow at the outlet of the high-temperature heat storage tank and the amount of steam generated by the steam generator to reduce the load to between 10% and 15% of the rated load; The preheater and steam generator stop running, the steam generation system stops supplying water, the saturated steam stored in the drum enters the superheater, and after being heated by the molten salt in the superheater, it is used to supply gas to the high-pressure cylinder. The molten salt in the superheater releases heat and flows back to the high-temperature heat storage tank; Continue to reduce the load of the high-pressure cylinder and the medium- and low-pressure cylinders from 10% of the rated load until the main steam valve is closed, and interlock the synchronous motor to disconnect from the grid; Turn on the SSS clutch self-locking function so that the high-pressure cylinder and the medium- and low-pressure cylinders can reduce the speed to stop synchronously with the SSS clutch.

9. The operating method according to claim 8, characterized in that: After the SSS clutch synchronously reduces the speed to a stop, the SSS clutch is still in an engaged state.

10. The operating method according to claim 2, characterized in that: When switching from shutdown to power generation, it includes: The molten salt in the high-temperature heat storage tank is sent to the superheater, the regenerator, the steam generator and the preheater for preheating, and the flow rate of the molten salt working medium at the outlet of the high-temperature heat storage tank is increased so that the amount of steam generated by the superheater and the reheater is gradually increased; The high pressure cylinder and the medium and low pressure cylinders are operated at a cranking speed, so that a speed difference is generated between the medium and low pressure cylinders and the synchronous motor, so that the SSS clutch is merged; The high-pressure cylinder and the medium- and low-pressure cylinders are connected to the synchronous motor, and warm-up, impulse running, speed increase, grid connection and load increase are performed in sequence. During the warm-up, impulse running, speed increase, grid connection and load increase, the SSS clutch is in the engaged state.

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