Efficient and stable ship hybrid power generation system and regulation and control method

Abstract

The invention provides an efficient and stable ship hybrid power generation system which comprises a hydrogen production unit and an ammonia supply system, and the hydrogen production unit comprises an ammonia decomposer, a hydrogen separator, a high-pressure hydrogen storage tank, a fuel cell and an ammonia-hydrogen internal combustion engine. The ammonia decomposer enables the ammonia flow to enter the ammonia decomposer in a segmented constant mode for catalytic decomposition through four set working conditions; the hydrogen separator is used for separating and purifying the generated mixed gas, and the separated and purified hydrogen is respectively fed into the fuel cell and the ammonia-hydrogen internal combustion engine through valves for power generation; the molten salt system recycles high-temperature tail gas of the ammonia-hydrogen internal combustion engine through the heat exchanger for heat energy storage and power generation through the steam Rankine cycle system. The regulation and control method is used for stabilizing the system and prolonging the service life of equipment by limiting the dynamic loading rate and start-stop times of the fuel cell and the ammonia-hydrogen internal combustion engine, and is used for waste heat recovery power generation through the molten salt and the steam expansion machine, so that the efficiency of the system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of ship hybrid power generation system control, and in particular to an efficient and stable ship hybrid power generation system and a control method. Background Art

[0002] Fuel cells have attracted much attention for their excellent power generation efficiency, but at this stage, their high cost and potential risk of performance degradation make relying solely on fuel cells for power supply not the best choice. To deal with these problems, a hybrid power generation solution that combines fuel cells with other power generation equipment is usually adopted to achieve a more stable and economical energy supply. Ammonia hydrogen internal combustion engines have become an ideal choice for cooperating with fuel cells to provide power for long-distance ships due to their wide power range, long service life and excellent endurance.

[0003] Hydrogen energy is one of the key energy sources for achieving energy transformation. It is mainly transported by road through long-tube trailers, while long-distance pipeline hydrogen transportation technology is still in the project demonstration stage. However, this method has problems such as high transportation costs and low efficiency, which seriously restricts the further development of the hydrogen energy industry.

[0004] Compared with hydrogen, ammonia has significant advantages in storage and transportation, and its system is mature and can achieve large-scale storage and transportation. Using ammonia as a hydrogen energy storage carrier can realize multiple functions such as online hydrogen production, separation and purification, and chemical power generation, effectively solving the safety problem during high-density storage and transportation of hydrogen, and providing a closed-loop solution for the utilization of zero-carbon ammonia hydrogen energy. Considering the large scale of my country's ammonia industry, mature technology and supporting facilities, and rich experience, the use of ammonia as a hydrogen energy storage carrier can significantly reduce the cost of hydrogen storage and transportation, which is an economical and effective way.

[0005] In order to match supply and demand and keep the system in a stable and efficient operating condition, it is necessary to formulate a suitable energy management strategy to achieve the target state. In view of the large fluctuation and high frequency of the load demand of ships, it is necessary to formulate a suitable strategy to optimize energy output and meet the power demand in real time.

[0006] At present, the existing technology for hybrid power generation system control methods mainly focuses on the regulation of system temperature and efficiency, and fails to consider the stability of the whole system from hydrogen production to power generation, the efficiency of ammonia hydrogen internal combustion engine and the influence of fuel cell attenuation rate on the system. The stability of the whole system is crucial to ensure that the hybrid power generation system can operate reliably under various working conditions. It directly affects the reliability and safety of the system, especially in occasions such as ships that require extremely high continuous power supply. The optimization and improvement of the efficiency of ammonia hydrogen internal combustion engine can significantly improve the utilization rate of energy and reduce fuel consumption. The inefficient operation of ammonia hydrogen internal combustion engine will increase energy costs and environmental burdens. At the same time, considering the regulation of fuel cell attenuation rate is related to the long-term operation efficiency and maintenance cost of the system, because the fuel cell is a key component in the hybrid system, and its performance attenuation will directly affect the performance and life of the whole system. The loss of core equipment such as fuel cells and ammonia hydrogen internal combustion engines will lead to frequent maintenance, which will affect the stability and reliability of the power generation system. Therefore, the stable and efficient regulation of the whole system of the hybrid power generation system for ship systems needs further research. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide an efficient and stable ship hybrid power generation system and control method, aiming to improve the power generation efficiency of the ammonia-hydrogen internal combustion engine, solve the problem of waste heat recovery and storage, and reduce the impact of frequent changes in the hydrogen production end on the stability of the system. In addition, the present invention also focuses on the dynamic load change rate of the power generation equipment, and achieves better energy management and power supply by improving the system's response ability to dynamic changes and enhancing its peak load performance.

[0008] In order to solve the above technical problems, the first implementation scheme provided by the present invention is to provide an efficient and stable ship hybrid power generation system, including a hydrogen production unit and an ammonia supply system, wherein the hydrogen production unit includes an ammonia decomposer, a hydrogen separator and a high-pressure hydrogen storage tank, the ammonia decomposer is connected to the ammonia supply system through a pipeline, a first flow detection unit and a first solenoid valve are arranged on the pipeline, the ammonia decomposer is connected to the hydrogen separator through a pipeline, the hydrogen separator is connected to the high-pressure hydrogen storage tank through a pipeline, a liquid level detection unit is arranged in the high-pressure hydrogen storage tank, and further includes: The fuel cell is connected to the high-pressure hydrogen storage tank through a pipeline and is used to generate electricity using hydrogen as a raw material. A second solenoid valve and a second flow detection unit are provided on the pipeline.

[0009] The ammonia-hydrogen internal combustion engine is connected to a high-pressure hydrogen storage tank through a pipeline. The ammonia-hydrogen internal combustion engine is also connected to an ammonia supply system through a pipeline to generate electricity using ammonia and hydrogen as raw materials. A third solenoid valve and a third flow detection unit are provided on the pipeline, and a fourth solenoid valve and a fourth flow detection unit are provided on the pipeline.

[0010] The first controller has a signal inlet end connected to the first flow detection unit, the second flow detection unit, the third flow detection unit, the fourth flow detection unit and the liquid level detection unit, respectively, and a signal outlet end connected to the first solenoid valve, the second solenoid valve, the third solenoid valve and the fourth solenoid valve. The first controller compares the measured value of the ammonia flow signal received at the signal inlet end with the corresponding ammonia intake amount under different liquid level setting values ​​of the high-pressure hydrogen storage tank, and then controls the opening of the first solenoid valve through the output signal, so that the ammonia decomposer performs ammonia feed regulation and hydrogen production; the first controller compares the measured value of the hydrogen flow signal received at the signal inlet end with the maximum hydrogen flow value corresponding to the maximum power obtained by both the ammonia-hydrogen internal combustion engine and the fuel cell, and the first controller compares the ammonia flow signal received at the signal inlet end with the maximum ammonia flow value corresponding to the maximum power obtained by the fuel cell, and then controls the opening of the second solenoid valve, the third solenoid valve and the fourth solenoid valve through the output signal to determine the hydrogen intake amount delivered by the high-pressure hydrogen storage tank to the fuel cell and the ammonia-hydrogen internal combustion engine and the ammonia amount delivered by the ammonia supply system to the fuel cell, thereby performing real-time power distribution for the fuel cell and the ammonia-hydrogen internal combustion engine.

[0011] Preferably, the ammonia supply system comprises: Liquid ammonia storage tanks; The evaporator is connected to the liquid ammonia storage tank through a pipeline, and a fifth solenoid valve and a fifth flow detection unit are arranged on the pipeline. The signal inlet end of the controller is connected to the fifth flow detection unit, and the signal outlet end of the controller is connected to the fifth solenoid valve. The ammonia flow signal measurement value received by the signal inlet end of the controller is compared with the corresponding ammonia intake amount under different liquid level setting values ​​of the high-pressure hydrogen storage tank, and then the opening of the fifth solenoid valve is controlled by the output signal, so that the evaporator can reasonably output ammonia according to the constant segmented ammonia feed control demand of the ammonia decomposer.

[0012] Preferably, it also includes a waste heat recovery power generation system, which includes a molten salt system and a steam Rankine cycle system, wherein the molten salt system includes a cold salt storage tank, a tail gas molten salt heat exchanger and a hot salt storage tank, and the steam Rankine cycle system includes: a water molten salt heat exchanger, a water tank and an expander, a first temperature sensor is provided in the cold salt storage tank, and a second temperature sensor is provided in the hot salt storage tank.

[0013] The exhaust gas molten salt heat exchanger is connected to the ammonia-hydrogen internal combustion engine through a heating pipe, and is used to exchange and store the high-temperature recovered exhaust gas of the ammonia-hydrogen internal combustion engine with the working fluid in the exhaust gas molten salt heat exchanger; the inlet of the exhaust gas molten salt heat exchanger is connected to the cold salt storage tank through a pipeline, and a sixth solenoid valve is provided on the pipeline, and the outlet of the exhaust gas molten salt heat exchanger is connected to the hot salt storage tank through a pipeline.

[0014] The water-molten salt heat exchanger is used to exchange heat between molten salt and water. Its liquid inlet is connected to the water tank through a pipeline, and a water pump and a seventh solenoid valve are provided on the pipeline. Its gas outlet is connected to the expander through a pipeline and is used to enable the expander to generate electricity. Its molten salt inlet is connected to the hot salt storage tank through a pipeline, and an eighth solenoid valve is provided on the pipeline. Its molten salt outlet is connected to the cold salt storage tank through a pipeline, and the water tank is connected to the expander through a pipeline.

[0015] The second controller has its signal inlet connected to the first temperature sensor and the second temperature sensor respectively, and its signal outlet connected to the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve respectively. The second controller compares the temperature signal measurement values ​​of the first temperature sensor and the second temperature sensor received at the signal inlet with the set temperature value, and then controls the opening of the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve through the output signal, so that the heat in the heating pipe is absorbed and utilized by the cold molten salt and then converted into hot molten salt and water for sufficient heat exchange for power generation.

[0016] Preferably, a temperature sensor is provided in the fuel cell, and the fuel cell is connected to the atmosphere through an air purifier; when the operating temperature of the fuel cell is lower than the set temperature, the power of the fuel cell is adjusted to the maximum power to complete the startup; when the operating temperature of the fuel cell reaches the set temperature, the air purifier is started to cool the fuel cell to an appropriate temperature.

[0017] Preferably, the fuel cell, expander, and ammonia-hydrogen internal combustion engine are all connected to the power consumption end via a converter.

[0018] Preferably, it also includes a battery for charging and discharging and storing electric energy of the ship hybrid power generation system, and the battery is connected to the converter for peak regulation and energy storage.

[0019] The second implementation scheme provided by the present invention is to provide an efficient and stable optimization algorithm for maximizing the efficiency of the ammonia-hydrogen internal combustion engine and the fuel cell of the ship hybrid power generation system, including: by judging the amount of hydrogen intake delivered to the fuel cell and the ammonia-hydrogen internal combustion engine and the amount of ammonia delivered to the fuel cell by the ammonia supply system, so as to perform real-time power distribution between the fuel cell and the ammonia-hydrogen internal combustion engine; the steps are as follows: Establish the relationship between the calorific value of hydrogen consumed by the fuel cell in the ship hybrid power generation system and the power generated by the fuel cell, and the relationship between the calorific value of hydrogen and ammonia consumed by the ammonia-hydrogen internal combustion engine and the power generated by the ammonia-hydrogen internal combustion engine.

[0020] The total calorific value of heat consumed in establishing a hybrid power generation system consisting of a fuel cell and an ammonia-hydrogen internal combustion engine.

[0021] According to the total calorific value of heat consumed by the hybrid power generation system and the power generation of the fuel cell and the ammonia hydrogen internal combustion engine, the maximum system efficiency function in the hybrid power generation system is established as: ; in It is the sum of the calorific value of fuel consumed by the fuel cell and the calorific value of fuel consumed by the ammonia hydrogen internal combustion engine. To generate power for fuel cells, The power generated by the ammonia hydrogen internal combustion engine; The constraints of the maximum system efficiency function in the hybrid power generation system are as follows: ; ; ; ; ; in P fc To generate power for fuel cells, P ICE The power generated by the ammonia hydrogen internal combustion engine, P ele It is the sum of the power generated by the fuel cell and the power generated by the ammonia hydrogen internal combustion engine; is the maximum power generation of the fuel cell; is the minimum power generation of the fuel cell.

[0022] The argmax function is used to limit the dynamic load change rate when the electric load condition is met to solve the fuel cell power output at the maximum efficiency of the hybrid power generation system: The power output of the ammonia hydrogen internal combustion engine is .

[0023] Power output of the fuel cell and ammonia hydrogen internal combustion engine at maximum efficiency through a hybrid power generation system 、 Real-time power allocation is performed on the power generation units to achieve maximum efficiency. At the same time, constraints are used to constrain the overshoot and increased stabilization time caused by the excessive dynamic load change rate of the fuel cell and the ammonia hydrogen internal combustion engine.

[0024] The third implementation scheme provided by the present invention is to provide an efficient and stable optimization algorithm for maximizing the efficiency of an ammonia-hydrogen internal combustion engine and a fuel cell of a ship hybrid power generation system. The ammonia decomposer regulates and controls the hydrogen production through constant segmented ammonia feed, wherein the constant segmented ammonia feed mode sets a corresponding constant ammonia flow rate in a specific power load interval, so that the ammonia decomposition flow rate remains constant within a certain power range, thereby avoiding the fluctuation of hydrogen production and hydrogen separation conditions caused by frequently changing working conditions, and reducing the efficiency loss and equipment wear caused thereby. The ammonia flow control method of the ammonia decomposer includes the following steps: The ammonia flow rate of the ammonia decomposer is adjusted by a step-by-step adjustment method, and the feed amount of the ammonia decomposer is divided into four working conditions according to the maximum ammonia flow rate. The load level of the ammonia decomposer is obtained according to the four different working conditions, wherein: P load ≤37.5%× P sysmax , n 3 =25%×n NH 3max ; 37.5%× P sysmax ≤ P load ≤62.5%× P sysmax , n 3 =50%× n 3max ; 62.5%× P sysmax ≤ P load ≤87.5%× P sysmax , n 3 =75%× n 3max ; 87.5%× P sysmax ≤ P load ≤100%× P sysmax , n 3 =100%× n 3max ; According to the liquid level and pressure of the high-pressure hydrogen storage tank, the feed ammonia flow rate of the ammonia decomposer is adjusted step by step. SOHC > SOHCmax When the feed ammonia flow rate is adjusted down by one level; when SOHC < SOHCmin When the feed ammonia flow rate is increased by one level; SOHC is the hydrogen storage state of the hydrogen storage tank; SOHCmax It is the maximum hydrogen storage state value of the hydrogen storage tank, ranging from 0 to 1; SOHCmin is the minimum hydrogen storage state value of the hydrogen storage tank; P sysmax Refers to the maximum power generation capacity designed for the hybrid power generation system; P load Refers to the ship's electricity demand; n3max Refers to the maximum molar flow rate of the ammonia decomposer.

[0025] The fourth implementation scheme provided by the present invention is to provide a method for controlling a waste heat recovery power generation system in a ship hybrid power generation system with high efficiency and stability, comprising the following steps: When the ammonia hydrogen internal combustion engine emits high-temperature exhaust gas, the controller controls the opening of the sixth solenoid valve through the output signal, and controls the flow rate of cold molten salt in the cold salt storage tank to ensure that the molten salt in the cold salt storage tank is fully heat-exchanged with the high-temperature exhaust gas sent to the exhaust molten salt heat exchanger to the molten salt storage temperature of the hot salt storage tank; at this time, the power generation power of the molten salt storage temperature of the hot salt storage tank is greater than zero; and when the steam Rankine cycle system has a power generation demand, the controller controls the opening of the seventh solenoid valve through the output signal to increase the sufficient water volume; the controller controls the eighth solenoid valve through the output signal and controls the flow rate of molten salt in the hot salt storage tank through the controller to ensure that the water sent to the water molten salt heat exchanger evaporates into superheated water steam greater than or equal to 95%, and the prepared superheated water steam enters the expander to generate electricity.

[0026] When the ammonia-hydrogen internal combustion engine has no high-temperature flue gas emissions, the controller closes the sixth solenoid valve to keep the hot salt storage temperature in the hot salt storage tank constant. There is no demand for power generation here. Under the premise that the ammonia-hydrogen energy ratio is a fixed ratio, the ammonia and hydrogen feed flow rates in the ammonia-hydrogen internal combustion engine can be adjusted.

[0027] The fifth implementation scheme provided by the present invention is to provide an efficient and stable method for regulating the real-time operating status and corresponding status of a ship in a ship hybrid power generation system. The real-time operating status of a ship is divided into four types: docking, leaving the port, normal navigation and berthing.

[0028] When the ship is docked, all equipment is shut down.

[0029] When the ship leaves the port, if the temperature of the fuel cell is lower than the set operating temperature, and when the load demand is lower than the difference between the maximum power of the fuel cell and the maximum charging power of the battery, the ammonia-hydrogen internal combustion engine is started to operate at the lowest load and the battery is charged; as the load demand increases, the fuel cell operates at the maximum power, the ammonia-hydrogen internal combustion engine still operates at the lowest load, and the battery absorbs excess power; when the load demand exceeds the maximum power of the fuel cell, the ammonia-hydrogen internal combustion engine is not shut down, the excess power is absorbed by the battery, and the insufficient power is also supplemented by the battery; if the temperature of the fuel cell is greater than or equal to the set operating temperature, the cooling water flow is adjusted to maintain the temperature balance of the fuel cell stack; at the same time, the power distribution of the fuel cell and the ammonia-hydrogen internal combustion engine is solved by the maximum efficiency optimization algorithm, and the battery fills the power that does not match the instantaneous load during the dynamic loading process; When the ship is sailing normally, if the temperature of the fuel cell is lower than the set working temperature, and the battery's current state of charge is within the normal range, the fuel cell still operates at maximum power. When the load demand is less than or equal to the sum of the maximum power of the fuel cell and the minimum power of the ammonia-hydrogen internal combustion engine, the ammonia-hydrogen internal combustion engine operates at minimum power and the battery is charged; when the load demand is greater than the sum of the maximum power of the fuel cell and the minimum power of the ammonia-hydrogen internal combustion engine, the ammonia-hydrogen internal combustion engine supplements the difference between the load demand and the maximum power of the fuel cell, and at the same time uses the heat energy stored in the waste heat power generation system to convert into electrical energy to charge the battery; when the temperature of the fuel cell is greater than or equal to the set working temperature, the cooling water flow is adjusted to maintain the temperature balance of the fuel cell stack; When the ship is at dock, if the current state of charge of the battery is less than the minimum state of charge, the thermal energy stored in the waste heat power generation system is converted into electrical energy to charge the battery. If the production capacity of the waste heat power generation system is insufficient to support the charging needs of the battery, the fuel cell and the ammonia-hydrogen internal combustion engine need to allocate an additional portion of power output to the battery while maintaining the load demand to perform necessary charging operations. When the current state of charge of the battery is greater than or equal to the minimum state of charge, the power allocation of the fuel cell and the ammonia-hydrogen internal combustion engine is solved by the maximum efficiency optimization algorithm.

[0030] Compared with the prior art, the present invention has the following beneficial effects: The present invention can maximize efficiency and solve the problem of low power generation efficiency of ammonia-hydrogen internal combustion engines when used alone by clarifying the differences in operating characteristics of fuel cells and ammonia-hydrogen internal combustion engines, and using a hybrid power generation system efficiency optimization algorithm to distribute power to power generation units in real time. The excessively high dynamic load change rate of fuel cells and ammonia-hydrogen internal combustion engines will lead to overshoot and increased stabilization time, which may cause equipment damage or failure. Due to technical limitations and external environmental influences, completely precise control is difficult to achieve, so it is necessary to limit the loading rate of power generation equipment within a safe range to adapt to the characteristics of large and high-frequency dynamic power fluctuations of ships. And through the coordinated regulation of batteries, the reliability and stability of the power generation process can be guaranteed.

[0031] Considering the frequent changes in the front-end hydrogen production conditions and the system turbulence, a constant segmented ammonia feed mode is adopted instead of the condition of changing the ammonia flow rate hour by hour, which can achieve a more stable and efficient hydrogen production process. Specifically, this mode sets the corresponding constant ammonia flow rate in a specific power load interval, so that the ammonia decomposition flow rate remains constant within a certain power range, thereby avoiding the fluctuations in hydrogen production and hydrogen separation conditions caused by frequent changes in conditions, and reducing the resulting efficiency loss and equipment wear. This step-by-step control operation is simpler, which helps to maintain the smooth operation of the electrolytic hydrogen production device and the stability of the hydrogen production quality, while also reducing the aging of equipment and shortened life due to frequent start and stop. In addition, the constant segmented ammonia feed mode helps to improve the response speed and adjustment accuracy of the system, better adapt to the volatility of the ammonia decomposer working conditions, and improve the flexibility and economy of the entire system. Therefore, this mode can effectively solve the problem of system fluctuations caused by frequent changes in hydrogen production conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the structure of a high-efficiency hybrid power generation system for ships according to the present invention; Figure 2 It is a flow chart of the ship operation status classification and corresponding status control method of the present invention; Figure 3 is a flow chart of the maximum optimization algorithm for the efficiency of the fuel cell and the ammonia hydrogen internal combustion engine of the present invention; Figure 4 is a schematic diagram of ammonia flow control of an ammonia decomposer of the present invention; Figure 5 It is a control flow chart of the waste heat recovery power generation system of the present invention; Description of reference numerals: 1. Liquid ammonia storage tank; 2. The eighth valve; 3. Evaporator; 4. The first valve; 5. The first ammonia delivery pipe; 6. The third valve; 7. Ammonia decomposer; 8. The second ammonia delivery pipe; 9. Mixing delivery pipe, 10. Hydrogen separator, 11. The first hydrogen delivery pipe; 12. High-pressure hydrogen storage tank, 13. The second valve, 14. The fourth valve, 15. The second hydrogen delivery pipe, 16. The third hydrogen delivery pipe; 17. Fuel cell, 18. Ammonia hydrogen internal combustion engine, 19. Heating pipe, 20. Cold salt storage tank, 21. The fifth valve, 22. Exhaust gas molten salt heat exchanger, 23. Hot molten salt delivery pipe, 24. Hot salt storage tank; 25. The seventh valve, 26. Water molten salt heat exchanger, 27. Cold molten salt delivery pipe, 28. Expander, 29. Water tank, 30. The sixth valve, 31. Water pump, 32. Steam delivery pipe, 33. Battery, 34. Converter, 35. Power consumption end. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present invention more obvious and understandable, 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 only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in 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.

[0034] The inventors found that due to the difficult ignition characteristics of ammonia, its combustion rate is significantly lower than that of hydrogen, which makes it complicated to achieve a stable combustion process. In addition, compared with traditional ammonia-hydrogen internal combustion engines, ammonia-hydrogen internal combustion engines have certain deficiencies in thermal efficiency and show a relatively low efficiency level. Therefore, improving the stability and efficiency of the ammonia-hydrogen internal combustion engine hybrid power generation system is particularly important for transportation equipment. Secondly, given that the flue gas temperature of ammonia-hydrogen internal combustion engines is relatively high, it has significant waste heat recovery potential. For traditional waste heat recovery methods, the high-temperature flue gas heat exchange is insufficient and there is still a large amount of low-temperature waste heat. Therefore, the waste heat power generation cycle power generation method is adopted to solve the problem of difficulty in recovering, storing and utilizing the waste heat of high-temperature flue gas of ammonia-hydrogen internal combustion engines, and at the same time, the power generation efficiency of ammonia-hydrogen internal combustion engines can be improved. Ammonia is the energy source of the entire hybrid power generation system, and the hydrogen production process of ammonia needs to obtain hydrogen through ammonia decomposition. Ammonia-hydrogen internal combustion engines and fuel cells have different requirements for hydrogen, and frequent adjustments to the working state of the hydrogen production end may cause fluctuations in system stability and efficiency. Therefore, optimizing the hydrogen production process and reducing system turbulence are crucial to improving the stability and efficiency of the entire hybrid power generation system. In view of this, the present invention provides an efficient and stable ship hybrid power generation system and control method, which can solve the problems of low power generation efficiency of ammonia-hydrogen internal combustion engines in the prior art, difficulty in waste heat recovery and storage, and system turbulence caused by frequent changes in the hydrogen production end. At the same time, the dynamic load change rate of the power generation equipment is taken into account to improve the dynamic response and peak-shaving capability of the system.

[0035] like Figure 1~Figure 5 As shown, an efficient and stable ship hybrid power generation system includes a hydrogen production unit and an ammonia supply system, the hydrogen production unit includes an ammonia decomposer 7, a hydrogen separator 10 and a high-pressure hydrogen storage tank 12, the ammonia decomposer 7 is connected to the ammonia supply system through a pipeline 5, the pipeline 5 is provided with a first flow detection unit and a first solenoid valve 4, the ammonia decomposer 7 is connected to the hydrogen separator 10 through a pipeline 9, the hydrogen separator 10 is connected to the high-pressure hydrogen storage tank 12 through a pipeline 11, the high-pressure hydrogen storage tank 12 is provided with a liquid level detection unit, and also includes: The fuel cell 17 is connected to the high-pressure hydrogen storage tank 12 via a pipeline 16 for generating electricity using hydrogen as a raw material. The pipeline 16 is provided with a second solenoid valve 13 and a second flow detection unit.

[0036] The ammonia-hydrogen internal combustion engine 18 is connected to the high-pressure hydrogen storage tank 12 through the pipeline 15. At the same time, the ammonia-hydrogen internal combustion engine 18 is also connected to the ammonia supply system through the pipeline 8 to generate electricity using ammonia and hydrogen as raw materials. The pipeline 15 is provided with a third solenoid valve 14 and a third flow detection unit, and the pipeline 8 is provided with a fourth solenoid valve 6 and a fourth flow detection unit.

[0037] The signal inlet end of the first controller is respectively connected to the first flow detection unit, the second flow detection unit, the third flow detection unit, the fourth flow detection unit and the liquid level detection unit, and the signal outlet end of the first controller is connected to the first solenoid valve 4, the second solenoid valve 13, the third solenoid valve 14 and the fourth solenoid valve 6. The first controller compares the ammonia flow signal measurement value received at the signal inlet end with the corresponding ammonia intake amount under different liquid level setting values ​​of the high-pressure hydrogen storage tank 12, and then controls the opening of the first solenoid valve 4 through the output signal, so that the ammonia decomposer 7 performs ammonia feed regulation and hydrogen production. The first controller receives the hydrogen flow signal at the signal inlet end. The signal measurement value is compared with the maximum hydrogen flow value corresponding to the maximum power obtained by both the ammonia-hydrogen internal combustion engine 18 and the fuel cell 17, and the first controller compares the ammonia flow signal received at the signal inlet end with the maximum ammonia flow value corresponding to the maximum power obtained by the fuel cell 17, and then controls the opening of the second solenoid valve 13, the third solenoid valve 14 and the fourth solenoid valve 6 through the output signal to determine the hydrogen intake amount delivered by the high-pressure hydrogen storage tank 12 to the fuel cell 17 and the ammonia-hydrogen internal combustion engine 18 and the ammonia amount delivered by the ammonia supply system to the fuel cell 17, thereby performing real-time power distribution to the fuel cell 17 and the ammonia-hydrogen internal combustion engine 18.

[0038] The specific structure of the ammonia supply system includes a liquid ammonia storage tank 1 and an evaporator 3, wherein the evaporator 3 is connected to the liquid ammonia storage tank 1 through a pipeline, and a fifth solenoid valve 2 and a fifth flow detection unit are arranged on the pipeline. The signal inlet end of the controller is connected to the fifth flow detection unit, and the signal outlet end of the controller is connected to the fifth solenoid valve 2. The ammonia flow signal measurement value received by the signal inlet end of the controller is compared with the corresponding ammonia intake amount under different liquid level setting values ​​of the high-pressure hydrogen storage tank 12, and then the opening of the fifth solenoid valve 2 is controlled by the output signal, so that the evaporator 3 can reasonably output ammonia according to the constant segmented ammonia feed control demand of the ammonia decomposer 7.

[0039] Specifically, the present invention also provides a waste heat recovery power generation system for long-distance ships that have certain energy storage requirements to enhance system reliability. The waste heat recovery power generation system includes a molten salt system and a steam Rankine cycle system, wherein the molten salt system includes a cold salt storage tank 20, an exhaust gas molten salt heat exchanger 22 and a hot salt storage tank 24, and the steam Rankine cycle system includes: a water molten salt heat exchanger 26, a water tank 29 and an expander 28, a first temperature sensor is provided in the cold salt storage tank 20, and a second temperature sensor is provided in the hot salt storage tank 24.

[0040] The exhaust gas molten salt heat exchanger 22 is connected to the ammonia hydrogen internal combustion engine 18 through a heating pipe 19, and is used to exchange heat and store the high-temperature recovered exhaust gas of the ammonia hydrogen internal combustion engine 18 with the working fluid in the exhaust gas molten salt heat exchanger 22; the inlet of the exhaust gas molten salt heat exchanger 22 is connected to the cold salt storage tank 20 through a pipeline, and a sixth solenoid valve 21 is provided on the pipeline, and the outlet of the exhaust gas molten salt heat exchanger 22 is connected to the hot salt storage tank 24 through a pipeline 23.

[0041] The water-molten salt heat exchanger 26 is used to exchange heat between molten salt and water. The liquid inlet of the water-molten salt heat exchanger 26 is connected to the water tank 29 through a pipeline, and a water pump 30 and a seventh solenoid valve 30 are provided on the pipeline. The gas outlet of the water-molten salt heat exchanger 26 is connected to the expander 28 through a pipeline, which is used to enable the expander 28 to generate electricity. The molten salt inlet of the water-molten salt heat exchanger 26 is connected to the hot salt storage tank 24 through a pipeline, and an eighth solenoid valve 25 is provided on the pipeline. The molten salt outlet of the water-molten salt heat exchanger 26 is connected to the cold salt storage tank 20 through a pipeline, and the water tank 29 is connected to the expander 28 through a pipeline.

[0042] The signal input end of the second controller is respectively connected to the first temperature sensor and the second temperature sensor, and the signal output end of the second controller is respectively connected to the sixth solenoid valve 21, the seventh solenoid valve 30 and the eighth solenoid valve 25. The controller compares the temperature signal measurement values ​​of the first temperature sensor and the second temperature sensor received at the signal input end with the set temperature value, and then controls the opening of the sixth solenoid valve 21, the seventh solenoid valve 30 and the eighth solenoid valve 25 through the output signal, so that the heat in the heating pipe 19 is absorbed and utilized by the cold molten salt and then converted into hot molten salt and water for sufficient heat exchange for power generation.

[0043] Specifically, the present invention provides a temperature control method for the fuel cell 17, wherein a temperature sensor is provided inside the fuel cell 17, and the fuel cell 17 is connected to the atmosphere through an air purifier; when the operating temperature of the fuel cell 17 is lower than the set temperature, the power of the fuel cell 17 is adjusted to the maximum power to complete the startup; when the operating temperature of the fuel cell 17 reaches the set temperature, the air purifier is started to cool the fuel cell 17 to an appropriate temperature.

[0044] Specifically, the fuel cell 17 , the expander 28 , and the ammonia hydrogen internal combustion engine 18 are all connected to the power consumption end 35 via a converter 34 , so as to provide power supply to the power consumption end 35 .

[0045] Preferably, it also includes a battery 33 for charging, discharging and storing electric energy of the ship hybrid power generation system, and the battery 33 is connected to a converter 34 for peak load regulation and energy storage.

[0046] like Figure 3As shown, an efficient and stable ship hybrid power generation system ammonia hydrogen ammonia hydrogen internal combustion engine and fuel cell efficiency maximization optimization algorithm includes determining the amount of hydrogen intake delivered to the fuel cell 17 and the ammonia hydrogen ammonia hydrogen internal combustion engine 18 and the amount of ammonia delivered to the fuel cell 17 by the ammonia supply system, thereby performing real-time power distribution between the fuel cell 17 and the ammonia hydrogen ammonia hydrogen internal combustion engine 18; the steps are as follows: Establish the relationship between energy consumption and power generation of ship hybrid power generation system; The relationship between the calorific value of the fuel hydrogen consumed by the fuel cell 17 and the power generation is: The relationship between the calorific value of the fuel hydrogen and ammonia consumed by the ammonia-hydrogen internal combustion engine 18 and the power generation power is as follows: The total calorific value of heat consumed by the hybrid power generation system composed of the fuel cell 17 and the ammonia-hydrogen internal combustion engine 18 is: The maximum system efficiency function in the hybrid power generation system is: ; in It is the sum of the calorific value of the fuel consumed by the fuel cell 17 and the calorific value of the fuel consumed by the ammonia hydrogen internal combustion engine 18. Generates power for the fuel cell 17, The power generated by the ammonia hydrogen internal combustion engine 18; The constraints of the maximum system efficiency function in the hybrid power generation system are as follows: ; ; ; ; ; in P fc Generates power for the fuel cell 17, P ICE The power generated by the ammonia hydrogen internal combustion engine 18 is P ele It is the sum of the power generated by the fuel cell 17 and the power generated by the ammonia hydrogen internal combustion engine 18; is the maximum power generation of the fuel cell 17; is the minimum power generation of the fuel cell 17 The argmax function is used to limit the dynamic load change rate when the electric load condition is met, so as to solve the power output of the fuel cell 17 at the maximum efficiency of the hybrid power generation system: The power output of the ammonia hydrogen internal combustion engine 18 is ; Power output by the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 at maximum efficiency of the hybrid power generation system 、 Real-time power distribution is performed on the power generation units to achieve maximum efficiency while limiting the overshoot and increased stabilization time caused by excessive dynamic load changes of the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 through constraints.

[0047] Specifically, Figure 4 As shown, an efficient and stable optimization algorithm for maximizing the efficiency of an ammonia-hydrogen internal combustion engine and a fuel cell of a ship hybrid power generation system: the ammonia decomposer 7 regulates and controls the hydrogen production through constant segmented ammonia feed, wherein the constant segmented ammonia feed mode sets a corresponding constant ammonia flow rate in a specific power load interval, so that the ammonia decomposition flow rate remains constant within a certain power range, thereby avoiding fluctuations in hydrogen production and hydrogen separation conditions caused by frequently changing operating conditions, and reducing the efficiency loss and equipment wear caused thereby, wherein the ammonia flow rate regulation method of the ammonia decomposer 7 comprises the following steps: The ammonia flow rate of the ammonia decomposer 7 is adjusted by a step-by-step adjustment method, and the feed amount of the ammonia decomposer 7 is divided into four working conditions according to the maximum ammonia flow rate, and the feed amount is divided into four working conditions according to 25%, 50%, 75% and 100% of the maximum ammonia flow rate. First, the ammonia decomposer working condition is determined according to the load level to obtain the load level of the ammonia decomposer 7, wherein:

[0048] P load ≤37.5%* P sys max , n 3 =25%*n NH 3 max ; 37.5%* P sys max ≤ P load ≤62.5%* P sys max , n 3 =50%* n 3max ; 62.5%* P sys max ≤ P load ≤87.5%* P sys max , n 3 =75%* n 3 max ; 87.5%* P sys max ≤ P load ≤100%* P sys max , n 3 =100%* n 3 max ; According to the liquid level of the high-pressure hydrogen storage tank 12 and the pressure of the high-pressure hydrogen storage tank 12, the feed ammonia flow rate of the ammonia decomposer 7 is adjusted stepwise. SOHC > SOHCmax When the feed ammonia flow rate is adjusted down by one level; when the high pressure hydrogen storage tank 12 SOHC < SOHCmin When the feed ammonia flow rate is increased by one level; SOHC is the hydrogen storage state of the hydrogen storage tank; SOHCmax It is the maximum hydrogen storage state value of the hydrogen storage tank, ranging from 0 to 1; SOHCmin is the minimum hydrogen storage state value of the hydrogen storage tank; P sysmax Refers to the maximum power generation capacity designed for the hybrid power generation system; P load Refers to the ship's electricity demand; n 3max Refers to the maximum molar flow rate of the ammonia decomposer.

[0049] like Figure 5 As shown, a method for controlling a waste heat recovery power generation system in an efficient and stable ship hybrid power generation system comprises the following steps: When the ammonia hydrogen internal combustion engine 18 emits high-temperature exhaust gas, the controller adjusts the fifth valve 2 and controls the flow rate of cold salt in the cold salt storage tank 20 to ensure that the molten salt in the cold salt storage tank 20 is fully heat-exchanged with the high-temperature exhaust gas sent to the exhaust molten salt heat exchanger 22 to the molten salt storage temperature of the hot salt storage tank 24; at this time, the power generation power of the molten salt storage temperature of the hot salt storage tank 24 is greater than zero; and when the steam Rankine cycle system has a power generation demand, the controller adjusts the opening of the sixth valve 30 to increase the sufficient water volume; adjusts the seventh valve 25 and controls the flow rate of molten salt in the hot salt storage tank 24 through the controller to ensure that the water sent to the water molten salt heat exchanger 26 evaporates into superheated water steam greater than or equal to 95%, and the prepared superheated water steam enters the expander 28 to generate electricity.

[0050] When the ammonia-hydrogen internal combustion engine 18 has no high-temperature flue gas emissions, the controller closes the fifth valve 21 to keep the storage temperature of the hot molten salt in the hot salt storage tank 24 constant. There is no demand for power generation here. Under the premise that the ammonia-hydrogen energy ratio is a fixed ratio, the ammonia and hydrogen feed flow rates in the ammonia-hydrogen internal combustion engine 18 can be adjusted.

[0051] like Figure 2As shown, the present invention provides a method for controlling the real-time operation state of a ship and the corresponding state in a highly efficient and stable ship hybrid power generation system. The real-time operation state of a ship is divided into four states: docking, leaving the port, normal sailing and docking. Different control methods correspond to different states. The ship operation status is divided into 4 working conditions: State0 = docking, State1 = leaving the port, State2 = normal sailing, State3 = docking. Different working conditions correspond to different control methods. The specific methods are as follows: First, the dynamic load rate of the fuel cell and ammonia hydrogen internal combustion engine is limited. ΔP fc max ≤ ΔP fc ≤ Δ P fc max 、- ΔP ICE max ≤ ΔP ICE ≤ ΔP ICE max This value is based on the life of the equipment and actual operation considerations, and is used to avoid irreversible performance degradation of the equipment due to large load changes.

[0052] When the ship is docked (State=0), all devices are turned off.

[0053] When the ship leaves the port (State=1), the temperature of the fuel cell is first determined T st Whether the set working temperature of 80℃ is reached or not, different temperature conditions correspond to different outputs. (1) When T st <80℃, if the load requirement P load Lower than the maximum power of fuel cell 17 P fc max Maximum charging power of battery 33 P bat char The difference is that the ammonia hydrogen internal combustion engine 18 is started and initially set to the minimum load operation state. P ICE low At the same time, the output power of the fuel cell 18 will be flexibly adjusted to P load + P bat char - P ICE low Power generation, battery 33 P bat char Charging; As the load demand increases to (P fc max - P bat char )~P fc max , the fuel cell 33 is at maximum power P fc max The ammonia hydrogen internal combustion engine 18 is still running at the minimum load P ICE low When the load demand exceeds P fc_max When the ammonia hydrogen internal combustion engine 18 P ICE low ~ P ICE max Generate electricity between the two terminals, thereby ensuring that the ammonia hydrogen internal combustion engine 18 is not shut down, the excess power is absorbed by the battery 33, and the insufficient power is also supplemented by the battery 33. The charging and discharging power of the battery 33 has a maximum power limit, that is, -P bat char ≤ P bat ≤ P bat dis ; (2) When Tst ≥ 80°C, the thermal management system of the fuel cell 17 will start to maintain the temperature balance of the stack by adjusting the cooling water flow. At the same time, the power distribution of the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 is solved by the maximum efficiency optimization algorithm ( Figure 3 ), the battery 33 fills the power of the instantaneous load mismatch during the dynamic loading process.

[0054] When the ship is sailing normally (State=2), the temperature state of the fuel cell 17 is first determined. (1) T st When the operating temperature is set to 80°C, the current state of charge (SOC) of the battery 33 is within the normal range, that is, SOC min ≤ SOC ≤ SOC max , the fuel cell 17 still operates at maximum power P fc max ,when P load ≤ P fc max + P ICE low When the ammonia hydrogen internal combustion engine 18 runs at minimum power, the battery 33 is charged; when P load >P fcmax + P ICE low When the ammonia hydrogen internal combustion engine 17 P load - P fc_maxProvide the power load, the system immediately evaluates the current capacity and redundancy of the waste heat power generation system. If the waste heat power generation system has sufficient margin, it will give priority to converting its stored heat energy into electrical energy to charge the battery 33. If the battery 33 is in a low range, that is, SOC ≤ SOC min , the battery 33 is at maximum power P bat char Charging, the ammonia hydrogen internal combustion engine 18 runs at minimum power, and the fuel cell 17 bears the remaining power to reach the set temperature as much as possible; if the battery 33 is in a high range, that is, SOC ≥ SOC max , the battery 33 is at maximum power P bat char The ammonia hydrogen internal combustion engine 18 operates at minimum power, and the fuel cell 17 takes on the remaining power to reach the set temperature as much as possible. (2) T st When the temperature is ≥80℃, the thermal management system of the fuel cell 17 will start to adjust the cooling water flow to maintain the temperature balance of the fuel cell stack. SOC ≤ SOC min , the battery 33 is at maximum power P bat char Charging, fuel cell 17 and ammonia hydrogen internal combustion engine 18 P fc +P ICE =P load +P bat char Perform optimization algorithm to allocate power; if SOC ≥ SOCmax , the battery 33 is at maximum power P bat_dis Discharge, fuel cell 17 and ammonia hydrogen internal combustion engine 18 to P fc + P ICE =P load -P bat dis Perform optimization algorithm to allocate power; if SOC min ≤ SOC ≤ SOC max , the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 are P fc +P ICE =P loadThe optimization algorithm is used to allocate power. If the waste heat power generation system has sufficient margin, the battery 33 is charged.

[0055] When the ship is at the port (State=3), the current state of charge SOC of the battery 33 is first determined. (1) SOC < SOC min When the system immediately evaluates the current capacity and redundancy of the waste heat power generation system, if the waste heat power generation system has sufficient margin, it will give priority to converting its stored heat energy into electrical energy to charge the battery 33. At this time, the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 focus on meeting the basic load demand of the ship during its stay in the port to ensure the stable operation of various systems of the ship, that is, P fc +P ICE =P load However, if the capacity of the waste heat power generation system is insufficient to support the charging demand of the battery 33, the system will automatically adjust the strategy. The fuel cell 17 and the ammonia hydrogen internal combustion engine 18 will need to allocate an additional portion of power output to the battery 33 while maintaining the load demand to perform the necessary charging operation, i.e. P fc +P ICE =P load +P bat char (2)When SOC ≥ SOC min When , the power distribution between the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 is solved by the maximum efficiency optimization algorithm, that is, P fc +P ICE =P load If the output power of the two is insufficient to fully meet the load demand due to the limitation of dynamic load change rate in certain periods, the remaining capacity of the battery 33 and the waste heat power generation system is mobilized to balance the electric energy.

[0056] That is, the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 are set with certain dynamic load rate limits during the power generation process to adapt to the dynamic power demand; and the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 are not shut down once started during the entire driving process; The output power distribution of the fuel cell 17 is determined based on the dual conditions of the current load demand and the temperature state of the fuel cell 17. When the temperature of the fuel cell 17 does not reach the optimal operating temperature, the fuel cell 17 operates at the maximum power to complete the startup; when the startup of the fuel cell 17 is completed, the power generation of the fuel cell 17 and the ammonia hydrogen internal combustion engine 18 is calculated and allocated by the maximum efficiency optimization algorithm; The waste heat recovery power generation system adjusts the flow rate of cold melted salt to store heat after sufficient heat exchange, and adjusts the flow rate of hot melted salt to heat water to the expander 28 for power generation; when the power generation power of the fuel cell 17, the ammonia hydrogen internal combustion engine 18 and the battery 33 meets the electricity demand, the waste heat system stores heat; when the power generation power of the fuel cell 17, the ammonia hydrogen internal combustion engine 18 and the battery 33 does not meet the electricity demand or the battery 33 SOC is lower than the lower limit, the waste heat system generates electricity for peak load regulation.

[0057] Specifically, when the SOC of the battery 33 is lower than the lower limit setting value, the system charges it at the maximum power; when the SOC of the battery 33 is higher than the upper limit setting value, the battery 33 discharges at the optimal power to maintain the SOC within the normal range.

[0058] The control strategy of the present invention comprehensively covers the entire operation cycle of the ammonia decomposition hydrogen production hybrid power generation system, and designs a set of dynamic control schemes for multi-device coordination from hydrogen production, hydrogen energy utilization to power generation. In the hydrogen production link, we adopt a step-by-step control method of constant flow segmented operation. According to the preset ammonia flow condition, it not only ensures the satisfaction of hydrogen energy demand, but also maintains the safety state of the hydrogen storage tank, and realizes the stable operation of the hydrogen production process. As for power generation, we have implemented a refined classification control strategy based on different working conditions to adapt to the power demand of ships under different operating conditions. This strategy divides the operating conditions of ships into four categories: docking, leaving the port, normal navigation and berthing. Different fuel cell-ammonia hydrogen internal combustion engine control strategies correspond to different working conditions. This control strategy effectively responds to the large and frequent fluctuations in ship electricity demand, ensures the dynamic stability of the fuel cell and ammonia hydrogen internal combustion engine system, and slows down the performance degradation of the fuel cell, creating a comprehensive control system for ships, and effectively promoting the progress of clean energy power generation technology in the transportation industry.

[0059] In addition, the present invention not only significantly improves the energy utilization efficiency by recovering and storing the heat of the high-temperature flue gas generated by the ammonia-hydrogen internal combustion engine, combined with the waste heat power generation technology, but also adds a more flexible and robust power supply option to the ammonia-hydrogen internal combustion engine power generation system. This technological innovation shows broad prospects in the field of clean energy applications and has made positive and important contributions to promoting the implementation of sustainable energy strategies. More importantly, the present invention effectively solves the problem of hydrogen energy storage and transportation by directly utilizing ammonia decomposition hydrogen production technology, and provides a highly matched power output capacity for power generation systems in the transportation field. At the same time, with the help of thermal energy storage and efficient utilization, the reliability and stability of the power generation system are significantly enhanced. In summary, the present invention is characterized by an innovative working mode and control method. By making full use of ammonia decomposition to produce hydrogen, the performance of the power generation system is effectively improved, and a positive contribution has been made to the development of the field of distributed power generation.

[0060] According to the power demand, determine the power load range to select the ammonia flow operating point, collect the hydrogen storage tank data to adjust the ammonia flow in a step-by-step manner; select the corresponding control strategy by classifying the ship's operating status, and allocate the output power of the fuel cell, ammonia hydrogen internal combustion engine, battery and waste heat recovery power generation system through the strategy; According to the real-time power demand, the total power generation of the ship hybrid power generation system is obtained by controlling the opening of the second solenoid valve 13 and the third solenoid valve 14 of the fuel cell 17, the opening of the first solenoid valve 4 and the fourth solenoid valve 6 of the ammonia hydrogen internal combustion engine 18, and the opening of the eighth solenoid valve 25 and the seventh solenoid valve 30 of the waste heat recovery power generation system; The total power generation of the system is compared with the real-time power demand, and the total power generation and power demand are matched by coordinated regulation of the current of the battery 33.

[0061] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An efficient and stable ship hybrid power generation system, including a hydrogen production unit and an ammonia supply system, characterized in that: The hydrogen production unit comprises an ammonia decomposer (7), a hydrogen separator (10) and a high-pressure hydrogen storage tank (12); the ammonia decomposer (7) is connected to an ammonia supply system via a pipeline (5); a first flow detection unit and a first solenoid valve (4) are provided on the pipeline (5); the ammonia decomposer (7) is connected to the hydrogen separator (10) via a pipeline (9); the hydrogen separator (10) is connected to the high-pressure hydrogen storage tank (12) via a pipeline (11); a liquid level detection unit is provided in the high-pressure hydrogen storage tank (12); and further comprises: A fuel cell (17) is connected to a high-pressure hydrogen storage tank (12) via a pipeline (16) and is used to generate electricity using hydrogen as a raw material. A second solenoid valve (13) and a second flow detection unit are provided on the pipeline (16); An ammonia-hydrogen internal combustion engine (18) is connected to a high-pressure hydrogen storage tank (12) via a pipeline (15). The ammonia-hydrogen internal combustion engine (18) is also connected to an ammonia supply system via a pipeline (8) to generate electricity using ammonia and hydrogen as raw materials, wherein a third solenoid valve (14) and a third flow detection unit are provided on the pipeline (15), and a fourth solenoid valve (6) and a fourth flow detection unit are provided on the pipeline (8); A first controller, whose signal inlet end is respectively connected to the first flow detection unit, the second flow detection unit, the third flow detection unit, the fourth flow detection unit and the liquid level detection unit, and whose signal outlet end is connected to the first solenoid valve (4), the second solenoid valve (13), the third solenoid valve (14) and the fourth solenoid valve (6). The first controller compares the measured value of the ammonia flow signal received at the signal inlet end with the corresponding ammonia intake amount under different liquid level setting values ​​of the high-pressure hydrogen storage tank (12), and then controls the opening of the first solenoid valve (4) through the output signal, so that the ammonia decomposer (7) performs ammonia feed regulation and controls the hydrogen production; the first controller compares the measured value of the hydrogen flow signal received at the signal inlet end with the ammonia intake amount corresponding to different liquid level setting values ​​of the high-pressure hydrogen storage tank (12), and then controls the opening of the first solenoid valve (4) through the output signal, so that the ammonia decomposer (7) performs ammonia feed regulation and controls the hydrogen production; The maximum hydrogen flow values ​​corresponding to the maximum power obtained by the hydrogen internal combustion engine (18) and the fuel cell (17) are compared, and the first controller compares the ammonia flow signal received at the signal inlet end with the maximum ammonia flow value corresponding to the maximum power obtained by the fuel cell (17), and then controls the opening of the second solenoid valve (13), the third solenoid valve (14) and the fourth solenoid valve (6) through the output signal to determine the hydrogen intake amount delivered by the high-pressure hydrogen storage tank (12) to the fuel cell (17) and the ammonia hydrogen internal combustion engine (18) and the ammonia supply system. The amount of ammonia delivered to the fuel cell (17) is determined, thereby performing real-time power distribution on the fuel cell (17) and the ammonia hydrogen internal combustion engine (18).

2. According to claim 1, a highly efficient and stable ship hybrid power generation system is characterized in that: The ammonia supply system comprises: Liquid ammonia storage tank (1); The evaporator (3) is connected to the liquid ammonia storage tank (1) through a pipeline, the pipeline is provided with a fifth solenoid valve (2) and a fifth flow detection unit, the signal inlet end of the controller is connected to the fifth flow detection unit, the signal outlet end of the controller is connected to the fifth solenoid valve (2), the ammonia flow signal measurement value received by the signal inlet end of the controller is compared with the corresponding ammonia intake amount under different liquid level setting values ​​of the high-pressure hydrogen storage tank (12), and then the opening of the fifth solenoid valve (2) is controlled by the output signal, so that the evaporator (3) outputs ammonia in accordance with the constant segmented ammonia feed control demand of the ammonia decomposer (7).

3. According to claim 1, a highly efficient and stable ship hybrid power generation system is characterized in that: A temperature sensor is provided in the fuel cell (17), and the fuel cell (17) is connected to the atmosphere via an air purifier; when the operating temperature of the fuel cell (17) is lower than a set temperature, the power of the fuel cell (17) is adjusted to a maximum power to complete the startup; when the operating temperature of the fuel cell (17) reaches the set temperature, the air purifier is started to cool the fuel cell (17) to a suitable temperature.

4. The efficient and stable ship hybrid power generation system according to claim 1 is characterized in that: It also includes a waste heat recovery power generation system, the waste heat recovery power generation system includes a molten salt system and a steam Rankine cycle system, wherein the molten salt system includes a cold salt storage tank (20), a tail gas molten salt heat exchanger (22) and a hot salt storage tank (24), the steam Rankine cycle system includes: a water molten salt heat exchanger (26), a water tank (29) and an expander (28), a first temperature sensor is provided in the cold salt storage tank (20), and a second temperature sensor is provided in the hot salt storage tank (24); The tail gas molten salt heat exchanger (22) is connected to the ammonia hydrogen internal combustion engine (18) via a heat supply pipe (19) and is used to exchange heat and store the high-temperature recovered tail gas of the ammonia hydrogen internal combustion engine (18) with the working fluid in the tail gas molten salt heat exchanger (22); the inlet of the tail gas molten salt heat exchanger (22) is connected to the cold salt storage tank (20) via a pipeline, and a sixth solenoid valve (21) is provided on the pipeline; the outlet of the tail gas molten salt heat exchanger (22) is connected to the hot salt storage tank (24) via a pipeline (23); A water-molten salt heat exchanger (26) for exchanging heat between molten salt and water, wherein the liquid inlet is connected to a water tank (29) via a pipeline, a water pump (31) and a seventh solenoid valve (30) are provided on the pipeline, the gas outlet is connected to an expander (28) via a pipeline, and is used to enable the expander (28) to generate electricity, the molten salt inlet is connected to a hot salt storage tank (24) via a pipeline, an eighth solenoid valve (25) is provided on the pipeline, the molten salt outlet is connected to a cold salt storage tank (20) via a pipeline, and the water tank (29) is connected to the expander (28) via a pipeline; The second controller has a signal inlet end connected to the first temperature sensor and the second temperature sensor respectively, and a signal outlet end connected to the sixth solenoid valve (21), the seventh solenoid valve (30) and the eighth solenoid valve (25) respectively. The second controller compares the temperature signal measurement values ​​of the first temperature sensor and the second temperature sensor received at the signal inlet end with the set temperature value, and then controls the opening of the sixth solenoid valve (21), the seventh solenoid valve (30) and the eighth solenoid valve (25) through the output signal, so that the heat in the heating pipe (19) is absorbed and utilized by the cold molten salt and then converted into hot molten salt and water to exchange heat for power generation.

5. The efficient and stable ship hybrid power generation system according to claim 4 is characterized in that: The fuel cell (17), the expander (28), and the ammonia-hydrogen internal combustion engine (18) are all connected to the power consumption end (35) via a converter (34).

6. The efficient and stable ship hybrid power generation system according to claim 5 is characterized in that: It also includes a storage battery (33) for charging, discharging and storing electric energy of the ship hybrid power generation system, wherein the storage battery (33) is connected to a converter (34) for peak load regulation and energy storage.

7. The efficient and stable ship hybrid power generation system according to claim 1 is characterized in that: The optimization algorithm for maximizing the efficiency of the ammonia hydrogen internal combustion engine and the fuel cell in the system is to determine the amount of hydrogen gas delivered to the fuel cell (17) and the ammonia hydrogen internal combustion engine (18) and the amount of ammonia delivered to the fuel cell (17) by the ammonia supply system, thereby performing real-time power distribution between the fuel cell (17) and the ammonia hydrogen internal combustion engine (18); the steps are as follows: Establishing a relationship between the calorific value of the fuel hydrogen consumed by the fuel cell (17) and the power generated by the fuel cell (17) in the ship hybrid power generation system, and a relationship between the calorific value of the fuel hydrogen and ammonia consumed by the ammonia hydrogen internal combustion engine (18) and the power generated by the ammonia hydrogen internal combustion engine (18); Establishing the total calorific value of heat consumed by a hybrid power generation system consisting of a fuel cell (17) and an ammonia hydrogen internal combustion engine (18); According to the total calorific value of the heat consumed by the hybrid power generation system and the power generated by the fuel cell (17) and the ammonia hydrogen internal combustion engine (18), the maximum system efficiency function in the hybrid power generation system is established as: ； in is the sum of the calorific value of the fuel consumed by the fuel cell (17) and the calorific value of the fuel consumed by the ammonia hydrogen internal combustion engine (18), The fuel cell (17) generates power, generating power for the ammonia hydrogen internal combustion engine (18); The constraints of the maximum system efficiency function in the hybrid power generation system are as follows: ； ； ； ； ； in P fc The fuel cell (17) generates power, P ICE The power generated by the ammonia hydrogen internal combustion engine (18) is P ele is the sum of the power generated by the fuel cell (17) and the power generated by the ammonia hydrogen internal combustion engine (18); is the maximum power generation of the fuel cell (17); is the minimum power generation of the fuel cell (17) The argmax function is used to limit the dynamic load change rate when the electric load condition is met, so as to solve the power output of the fuel cell (17) at the maximum efficiency of the hybrid power generation system: and the power output of the ammonia hydrogen internal combustion engine (18) is ; Power output from the fuel cell (17) and ammonia hydrogen internal combustion engine (18) at maximum efficiency of the hybrid power generation system 、 The power generation units are allocated in real time to achieve maximum efficiency while limiting the overshoot and increase in stabilization time caused by excessive dynamic load change rates of the fuel cell (17) and the ammonia hydrogen internal combustion engine (18) through constraint conditions.

8. The efficient and stable ship hybrid power generation system according to claim 7 is characterized in that: In the system, the ammonia decomposer (7) of the ammonia hydrogen internal combustion engine and fuel cell efficiency maximization optimization algorithm controls the hydrogen production through constant segmented ammonia feed regulation and control, wherein the constant segmented ammonia feed mode sets a corresponding constant ammonia flow rate in a specific power load interval, so that the ammonia decomposition flow rate remains constant within a certain power range, thereby avoiding the fluctuation of hydrogen production and hydrogen separation conditions caused by frequently changing working conditions, and reducing the efficiency loss and equipment wear caused thereby. The ammonia flow control method of the ammonia decomposer (7) includes the following steps: The ammonia flow rate of the ammonia decomposer (7) is adjusted by a step-by-step adjustment method, and the feed rate of the ammonia decomposer (7) is divided into four operating conditions according to the maximum ammonia flow rate. The load level of the ammonia decomposer (7) is obtained according to the four different operating conditions, wherein: P load ≤37.5%× P sysmax ， n 3 =25%×n NH 3max ； 5%× P sysmax ≤ P load ≤62.5%× P sysmax ， n 3 =50%× n 3max ； 5%× P sysmax ≤ P load ≤87.5%× P sysmax ， n 3 =75%× n 3max ； 5%× P sysmax ≤ P load ≤100%× P sysmax ， n 3 =100%× n 3max ； The feed ammonia flow rate of the ammonia decomposer (7) is adjusted in a step-wise manner according to the liquid level of the high-pressure hydrogen storage tank (12) and the pressure of the high-pressure hydrogen storage tank (12). SOHC > SOHCmax When the feed ammonia flow rate is adjusted down by one level; when the high pressure hydrogen storage tank (12) SOHC < SOHCmin When the feed ammonia flow rate is increased by one level; SOHC is the hydrogen storage state of the hydrogen storage tank; SOHCmax It is the maximum hydrogen storage state value of the hydrogen storage tank, ranging from 0 to 1; SOHCmin is the minimum hydrogen storage state value of the hydrogen storage tank; P sysmax Refers to the maximum power generation capacity designed for the hybrid power generation system; P load Refers to the ship's electricity demand; n 3max Refers to the maximum molar flow rate of the ammonia decomposer.

9. The efficient and stable ship hybrid power generation system according to claim 4, characterized in that: The control method of the waste heat recovery power generation system in the system includes the following steps: When the ammonia hydrogen internal combustion engine (18) emits high-temperature exhaust gas, the controller controls the opening of the sixth solenoid valve (21) through an output signal, and controls the flow rate of cold molten salt in the cold salt storage tank (20) to ensure that the molten salt in the cold salt storage tank (20) is fully heat-exchanged with the high-temperature exhaust gas sent to the exhaust gas molten salt heat exchanger (22) to the molten salt storage temperature of the hot salt storage tank (24); at this time, the power generation power of the molten salt storage temperature of the hot salt storage tank (24) is greater than zero; and when the steam Rankine cycle system has a power generation demand, the controller controls the opening of the seventh solenoid valve (30) through an output signal to increase the sufficient water volume; the controller controls the eighth solenoid valve (25) through an output signal and controls the flow rate of molten salt in the hot salt storage tank (24) through the controller to ensure that the water sent to the water molten salt heat exchanger (26) evaporates into superheated water steam greater than or equal to 95%, and the prepared superheated water steam enters the expansion machine (28) to generate electricity; When the ammonia-hydrogen internal combustion engine (18) has no high-temperature flue gas emissions, the controller closes the sixth solenoid valve (21) to keep the hot salt storage temperature in the hot salt storage tank (24) constant. There is no demand for power generation. Under the premise that the ammonia-hydrogen energy ratio is a fixed ratio, the ammonia and hydrogen feed flow rates in the ammonia-hydrogen internal combustion engine (18) can be adjusted.

10. The control method of a highly efficient and stable ship hybrid power generation system according to claim 6, characterized in that: The real-time operation status of a ship is divided into four categories: docking, departure, normal navigation and berthing: When the ship is docked, all equipment is shut down; When the ship leaves the port, if the temperature of the fuel cell (17) is less than the set working temperature, and when the load demand is lower than the difference between the maximum power of the fuel cell (17) and the maximum charging power of the battery (33), the ammonia hydrogen internal combustion engine (18) is started to operate at the minimum load state, and the battery (33) is charged; as the load demand increases, the fuel cell (17) operates at the maximum power, the ammonia hydrogen internal combustion engine (18) still operates at the minimum load, and the battery (33) absorbs excess electric energy; when the load demand exceeds the maximum power of the fuel cell (17), the ammonia hydrogen internal combustion engine (18) is not shut down, and the excess electric power is absorbed by the battery (33), and the insufficient electric power is also supplemented by the battery (33); if the temperature of the fuel cell (17) is greater than or equal to the set working temperature, the cooling water flow is adjusted to maintain the temperature balance of the fuel cell (17) stack; at the same time, the power distribution of the fuel cell (17) and the ammonia hydrogen internal combustion engine (18) is solved by the maximum efficiency optimization algorithm, and the battery (33) fills the power that does not match the instantaneous load during the dynamic loading process; When the ship is sailing normally, if the temperature of the fuel cell (17) is lower than the set working temperature and the current state of charge of the storage battery (33) is within the normal range, the fuel cell (17) still operates at maximum power; when the load demand is less than or equal to the sum of the maximum power of the fuel cell (17) and the minimum power of the ammonia-hydrogen internal combustion engine (18), the ammonia-hydrogen internal combustion engine (18) operates at minimum power and the storage battery (33) is charged; when the load demand is greater than the sum of the maximum power of the fuel cell (17) and the minimum power of the ammonia-hydrogen internal combustion engine (18), the ammonia-hydrogen internal combustion engine (18) supplements the difference between the load demand and the maximum power of the fuel cell (17), and at the same time utilizes the heat energy stored in the waste heat power generation system to convert into electrical energy to charge the storage battery (33); when the temperature of the fuel cell (17) is greater than or equal to the set working temperature, the cooling water flow is regulated to maintain the temperature balance of the fuel cell (17) stack; When the ship is at a port, if the current state of charge of the storage battery (33) is less than the minimum state of charge, the thermal energy stored in the waste heat power generation system is preferentially converted into electrical energy to charge the storage battery (33). If the capacity of the waste heat power generation system is insufficient to support the charging demand of the storage battery (33), the fuel cell (17) and the ammonia hydrogen internal combustion engine (18) need to allocate an additional portion of power output to the storage battery (33) while maintaining the load demand to perform necessary charging operations. When the current state of charge of the storage battery (33) is greater than or equal to the minimum state of charge, the power allocation of the fuel cell (17) and the ammonia hydrogen internal combustion engine (18) is solved by a maximum efficiency optimization algorithm.

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