Stirling power generation system driven by deep-sea hot spring absorption type heat pump and control method of Stirling power generation system

Abstract

The invention discloses a Stirling power generation system driven by a deep-sea hot spring absorption type heat pump and a control method of the Stirling power generation system. The system comprises a Stirling power generator and a heat pump. The heat pump comprises a first liquid storage tank, a third pump, a hot spring heat exchange assembly, a condensation heat exchanger and a condenser. The first liquid storage tank is used for storing a heat pump working medium; the third pump is used for extracting the heat pump working medium from the first liquid storage tank and conveying the heat pump working medium to the hot spring heat exchange assembly; the hot spring heat exchange assembly is used for heating a heat pump working medium through a deep sea hot spring and conveying the heated heat pump working medium to the condensation heat exchanger. The heat pump working medium releases heat in the condensation heat exchanger and then flows to the condenser for condensation, and the condensed heat pump working medium flows to the first liquid storage tank; the condensation heat exchanger is arranged on a heat head of the Stirling generator and used for conducting heat energy generated by heat release of the heat pump working medium to a power generation working medium in the Stirling generator for power generation.

Description

Technical Field

[0001] This invention relates to the field of thermal energy-driven power generation technology, and in particular to a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump and its control method. Background Technology

[0002] Deep-sea hydrothermal vents are unique geological structures formed by high-temperature fluids seeping from fissures in the ocean floor. They are commonly found in active regions such as mid-ocean ridges and subduction zones, with fluid temperatures ranging from 60°C to 400°C. Different vent types, such as black smokers or white smokers, exhibit variations. Deep-sea hydrothermal vents not only contain abundant minerals but also, due to the significant temperature difference between them and the surrounding cold seawater, serve as a potential sustainable energy source. This temperature gradient provides a natural application scenario for thermal power generation technology.

[0003] The long-term stable operation of deep-sea equipment (such as scientific sensors, unmanned underwater vehicles, and resource extraction devices) relies on a continuous power supply. Current power supply methods include submarine cables, high-voltage battery packs, and small nuclear power plants. Among these, submarine cables are costly to deploy and difficult to maintain; battery energy density is limited and cannot support long-term missions; and nuclear power sources face radioactive risks and challenges in adapting to the harsh deep-sea environment. These limitations result in low power supply reliability and short operating cycles for deep-sea equipment, severely restricting deep-sea resource development and scientific research. As an external combustion thermodynamic cycle power generation device, the Stirling generator generates electricity by driving a piston through the thermal expansion and contraction of the working fluid between a high-temperature heat source and a low-temperature cold source. It can operate continuously for more than 10 years. Its closed-loop structure is highly compatible with complex fluid environments. Based on the natural temperature difference between deep-sea hydrothermal vents and the surrounding seawater, the Stirling generator can achieve efficient energy conversion without fuel combustion. It is suitable for high-pressure and corrosive deep-sea environments. By integrating hydrothermal vent energy utilization devices with Stirling generators, an autonomous and zero-emission power supply system can be built, breaking through the endurance and safety bottlenecks of traditional technologies and providing a stable, highly reliable, and sustainable power solution for deep-sea operations.

[0004] Therefore, a new technical solution is urgently needed to address the technical problem of how to achieve continuous power supply for deep-sea operation equipment based on Stirling generators. Summary of the Invention

[0005] This invention provides a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump and its control method, in order to solve the technical problem of how to achieve continuous power supply for deep-sea operation equipment based on a Stirling generator.

[0006] To achieve the above objectives, the present invention provides a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump, comprising a Stirling generator and a heat pump; the heat pump includes a first liquid storage tank, a third pump, a hydrothermal vent heat exchange assembly, a condenser heat exchanger, and a condenser.

[0007] The first storage tank is used to store the heat pump working fluid; the third pump is used to extract the heat pump working fluid from the first storage tank and deliver the heat pump working fluid to the hot spring heat exchange component; the hot spring heat exchange component is used to heat the heat pump working fluid through the deep-sea hot spring and deliver the heated heat pump working fluid to the condenser heat exchanger; after releasing heat in the condenser heat exchanger, the heat pump working fluid flows to the condenser for condensation, and the condensed heat pump working fluid flows back to the first storage tank.

[0008] The condenser heat exchanger is installed at the hot head of the Stirling generator to transfer the heat energy generated by the heat pump working fluid to the power generation working fluid in the Stirling generator for power generation.

[0009] Preferably, the heat pump also includes a first regulating valve, a temperature sensor, and a temperature control module.

[0010] The first regulating valve is located between the third pump and the hot spring heat exchange component, and is used to regulate the flow rate of the heat pump working fluid entering the hot spring heat exchange component; the temperature sensor is located between the hot spring heat exchange component and the condenser heat exchanger, and is used to monitor the temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component; both the first regulating valve and the temperature sensor are connected to the temperature control module, and the temperature control module is used to change the opening degree of the first regulating valve according to the temperature of the heat pump working fluid monitored by the temperature sensor.

[0011] Preferably, changing the opening degree of the first regulating valve based on the heat pump working fluid temperature monitored by the temperature sensor includes: When the temperature sensor detects that the heat pump working fluid temperature at the outlet of the hot spring heat exchange component is lower than the preset value, the temperature control module reduces the opening of the first regulating valve to reduce the flow rate and increase the heat pump working fluid temperature at the outlet of the hot spring heat exchange component; when the temperature sensor detects that the heat pump working fluid temperature at the outlet of the hot spring heat exchange component is higher than the preset value, the temperature control module increases the opening of the first regulating valve to increase the flow rate and decrease the heat pump working fluid temperature at the outlet of the hot spring heat exchange component.

[0012] Preferably, the heat pump also includes a first pump; The first pump is located between the condenser and the first liquid storage tank, and is used to drive the heat pump working fluid from the hot spring heat exchange components toward the condenser to the first liquid storage tank.

[0013] Preferably, the Stirling power generation system also includes a cooling circuit; the cooling circuit includes a second liquid storage tank, a second pump, a seawater cooling device, a second regulating valve, and heat exchange pipes.

[0014] The second storage tank is used to store the cooling medium; the second pump is used to drive the cooling medium in the cooling circuit to flow along the direction of the second storage tank, the seawater cooling device, the second regulating valve, the heat exchange pipe and the second storage tank.

[0015] The heat exchange pipes are installed at the cooler of the Stirling generator to absorb the heat of the power-generating fluid in the Stirling generator, thereby increasing the temperature difference between the hot and cold ends of the Stirling generator. They are also used for heat dissipation of the linear motor in the Stirling generator. The seawater cooling device is used to absorb the heat of the cooling fluid in the cooling circuit through deep-sea cold water. The second regulating valve is used to control the flow rate of the cooling fluid in the heat exchange pipes to ensure that the temperature of the cooling fluid is within a preset range when it flows through the cooler of the Stirling generator.

[0016] Preferably, the Stirling power generation system also includes a pressure control module; the pressure control module includes a pressure gauge, a filling control branch, and a high-pressure gas cylinder.

[0017] The pressure gauge is used to monitor the gas pressure of the working fluid in the Stirling generator. When the gas pressure is lower than the preset value, the high-pressure gas cylinder is driven to replenish the working fluid in the Stirling generator through the gas filling control branch.

[0018] Preferably, the Stirling power generation system also includes a power distribution module; The power distribution module includes transmission lines, dual active bridge converters, DC distribution network, bidirectional DC-DC converters, and energy storage batteries; the dual active bridge converter includes frequency converters, high-frequency transformers, and rectifiers.

[0019] The power transmission line is connected to the linear motor mover of the Stirling generator to output the electrical energy generated by the Stirling generator. After the electrical energy is output, it is divided into two paths after passing through a frequency converter, a high-frequency transformer and a rectifier. One path is output to the DC distribution network to power the deep-sea equipment mounted on the DC distribution network, and the other path is output to the energy storage battery through a bidirectional DC-DC converter for energy storage.

[0020] The present invention also provides a control method for a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump, used in the system of the present invention, the control method comprising: Set the rated value and allowable fluctuation range of the bus voltage of the DC distribution network; collect the bus voltage of the DC distribution network; obtain the bus voltage deviation based on the rated value and bus voltage; obtain the target power output value of the Stirling generator based on the bus voltage deviation and allowable fluctuation range.

[0021] The target power generation value is obtained by querying the pre-calibrated power-temperature-flow correspondence table to obtain the target flow rate of the first regulating valve and the target temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component. The initial opening value of the first regulating valve is obtained based on the target flow rate of the first regulating valve. The initial opening value is assigned to the first regulating valve and corrected based on the actual temperature and target temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component.

[0022] The temperature at the inlet end of the heat exchange pipe flowing through the cooler is monitored in real time and recorded as the first temperature. The first temperature is compared with the first temperature setpoint to obtain the cold end temperature deviation. The first temperature setpoint is set to be close to the deep-sea cold water temperature. The second opening value is obtained based on the cold end temperature deviation and the PI controller, and the second opening value is assigned to the second regulating valve.

[0023] Preferably, the correction of the initial opening value based on the actual temperature and target temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component includes: The actual temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component is collected in real time by the temperature sensor; the temperature deviation is obtained based on the target temperature and the actual temperature; the opening correction value of the first regulating valve is obtained based on the temperature deviation and the PID controller; the initial opening value is corrected based on the opening correction value to obtain the first opening value, and the first opening value is assigned to the first regulating valve.

[0024] Preferably, the target power output value of the Stirling generator is obtained based on the bus voltage deviation and allowable fluctuation range, including: Define the bus voltage deviation as The allowable fluctuation range is Then it includes: when At that time, the Stirling power generation system is in equilibrium, and the Stirling generator maintains its current power output.

[0025] when If the generator is found to be generating excess power, the bidirectional DC-DC converter is controlled to store the excess power into the energy storage battery; if the energy storage battery is full, the power generation of the Stirling generator is reduced.

[0026] when When the system detects insufficient power generation or increased load, it controls the energy storage battery to discharge through the bidirectional DC-DC converter to compensate for the power deficit, while simultaneously controlling the increase of the Stirling generator's power generation.

[0027] In practice, the actual target power generation value is obtained.

[0028] The present invention has the following beneficial effects: This invention relates to a deep-sea hydrothermal vent absorption heat pump-driven Stirling power generation system. Using a hydrothermal vent heat exchange component, the system leverages heat pump technology to utilize the thermal energy from the deep-sea hydrothermal vent to provide a heat source for the Stirling generator. Deep-sea cold water provides a cooling source for the Stirling generator's cooler. Driven by the natural temperature difference of seawater, the Stirling generator offers advantages such as no fuel supply required, zero pollution, and high reliability, and is highly adaptable to the extreme deep-sea environment. The circulating heat pump working fluid, both heating and releasing heat, provides a continuous heat source for the system, enabling sustainable and green power generation and solving the power supply problem for deep-sea equipment.

[0029] The control method for a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump, as described in this invention, is based on the system of this invention and possesses the same beneficial effects. Furthermore, the method of this invention ensures that the output power of the Stirling generator matches the deep-sea load demand and the energy storage system status, maintains the hot-end temperature of the Stirling generator within its optimal operating range, and simultaneously controls the cold-end temperature to guarantee a sufficient temperature difference. This enables the system to operate efficiently, stably, and automatically under different heat source conditions and load demands, providing a stable and sustainable power guarantee for deep-sea equipment, and has excellent application value and prospects.

[0030] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0031] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of a Stirling power generation system according to a preferred embodiment of the present invention.

[0032] Figure 2 This is a schematic diagram of a Stirling generator according to a preferred embodiment of the present invention.

[0033] In the attached diagram: 1. Power transmission line; 2. Frequency converter; 3. High-frequency transformer; 4. Rectifier; 5. DC distribution network; 6. Energy storage battery; 7. Bidirectional DC-DC converter; 8. Stirling generator; 9. Thermal insulation layer; 10. Condensing heat exchanger; 11. Condenser; 12. First pump; 13. First liquid storage tank; 14. Third pump; 15. First regulating valve; 16. Heat exchanger; 17. Heat collection fins; 18. Hot spring heat exchange assembly; 19. Temperature sensor; 20. Temperature control module; 21. Pressure gauge; 22. Gas filling control branch; 23. High-pressure gas cylinder; 24. Heat exchange pipeline; 25. Second regulating valve; 26. Seawater cooling device; 27. Second pump; 28. Second liquid storage tank.

[0034] 8-1. Back pressure chamber; 8-2. Gas distribution piston leaf spring; 8-3. Power piston leaf spring; 8-4. Cylinder; 8-5. Linear motor end cover; 8-6. Linear motor mover; 8-7. Linear motor stator magnet; 8-8. Linear motor stator; 8-9. Cooler; 8-10. Regenerator; 8-11. Heater; 8-12. Power piston; 8-13. Gas distribution piston; 8-14. Hot head; 8-15. Expansion chamber; 8-16. Compression chamber. Detailed Implementation

[0035] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0036] See Figure 1 In a preferred embodiment of the present invention, a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump is provided, including a Stirling generator 8 and a heat pump; the heat pump includes a first liquid storage tank 13, a third pump 14, a hydrothermal vent heat exchange assembly 18, a condenser heat exchanger 10 and a condenser 11.

[0037] The first storage tank 13 is used to store the heat pump working fluid; the third pump 14 is used to extract the heat pump working fluid from the first storage tank 13 and transport the heat pump working fluid to the hot spring heat exchange component 18; the hot spring heat exchange component 18 is used to heat the heat pump working fluid through the deep-sea hot spring and transport the heated heat pump working fluid to the condenser heat exchanger 10; after the heat pump working fluid releases heat in the condenser heat exchanger 10, it flows to the condenser 11 for condensation, and the condensed heat pump working fluid flows back to the first storage tank 13, forming a heat pump working fluid circulation loop.

[0038] In a preferred embodiment of the present invention, the hot spring heat exchange component 18 includes a heat exchanger 16 and heat collection fins 17, which are used to absorb the heat from the deep-sea hot spring and transfer it to the heat pump working fluid. The heat collection fins 17 can increase the heat absorption area.

[0039] In a preferred embodiment of the present invention, the liquid storage tank can balance the fluctuation of the circulating flow rate and improve the stability of the entire system operation.

[0040] The condenser heat exchanger 10 is installed on the hot head 8-14 of the Stirling generator 8 to transfer the heat energy generated by the heat pump working fluid to the power generation working fluid in the Stirling generator 8 for power generation.

[0041] In a preferred embodiment of the present invention, water is selected as the heat pump working fluid, and helium is selected as the power generation working fluid; however, other fluids may be selected as needed. The heat pump working fluid is transported within the heat pump via pipelines.

[0042] In a preferred embodiment of the present invention, the heat pump further includes a first regulating valve 15, a temperature sensor 19, and a temperature control module 20; The first regulating valve 15 is located between the third pump 14 and the hot spring heat exchange component 18, and is used to regulate the flow rate of the heat pump working fluid entering the hot spring heat exchange component 18; the temperature sensor 19 is located between the hot spring heat exchange component 18 and the condenser heat exchanger 10, and is used to monitor the temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component 18; both the first regulating valve 15 and the temperature sensor 19 are connected to the temperature control module 20, and the temperature control module 20 is used to change the opening degree of the first regulating valve 15 according to the temperature of the heat pump working fluid monitored by the temperature sensor 19, specifically including: When temperature sensor 19 detects that the heat pump working fluid temperature at the outlet of the hot spring heat exchange component 18 is lower than a preset value, temperature control module 20 reduces the opening of the first regulating valve 15 to decrease the flow rate and increase the heat pump working fluid temperature at the outlet of the hot spring heat exchange component 18. When temperature sensor 19 detects that the heat pump working fluid temperature at the outlet of the hot spring heat exchange component 18 is higher than the preset value, temperature control module 20 increases the opening of the first regulating valve 15 to increase the flow rate and decrease the heat pump working fluid temperature at the outlet of the hot spring heat exchange component 18. Through the above adjustments, the heat supply of the heat pump working fluid to the Stirling generator 8 is ensured to meet the actual power generation requirements, thus ensuring the stable performance of the Stirling generator 8.

[0043] In a preferred embodiment of the present invention, the heat pump further includes a first pump 12; the first pump 12 is disposed between the condenser 11 and the first liquid storage tank 13, and is used to drive the heat pump working fluid from the hot spring heat exchange component 18 to the condenser 11 to the first liquid storage tank 13.

[0044] In a preferred embodiment of the present invention, the Stirling power generation system further includes a cooling circuit; the cooling circuit includes a second liquid storage tank 28, a second pump 27, a seawater cooling device 26, a second regulating valve 25, and a heat exchange pipe 24; The second liquid storage tank 28 is used to store the cooling medium; the second pump 27 is used to drive the cooling medium in the cooling circuit to flow along the direction of the second liquid storage tank 28, the seawater cooling device 26, the second regulating valve 25, the heat exchange pipe 24 and the second liquid storage tank 28. The heat exchange pipe 24 is installed at the cooler 8-9 of the Stirling generator 8 to absorb the heat of the power generation medium in the Stirling generator 8, thereby increasing the temperature difference between the hot and cold ends of the Stirling generator 8 and improving the power generation efficiency. It is also used for heat dissipation of the linear motor in the Stirling generator 8. The seawater cooling device 26 is used to absorb the heat of the cooling medium in the cooling circuit through deep-sea cold water and reduce the temperature of the cooling medium. The second regulating valve 25 is used to control the flow rate of the cooling medium in the heat exchange pipe 24 to ensure that the temperature of the cooling medium is within a preset range when it flows through the cooler 8-9 of the Stirling generator 8.

[0045] In a preferred embodiment of the present invention, the Stirling power generation system further includes a pressure control module; the pressure control module includes a pressure gauge 21, a filling control branch 22, and a high-pressure gas cylinder 23; Pressure gauge 21 is used to monitor the gas pressure of the working fluid in Stirling generator 8. When the gas pressure is lower than the preset value, the high-pressure gas cylinder 23 is driven by the gas filling control branch 22 to replenish the working fluid in Stirling generator 8.

[0046] In a preferred embodiment of the present invention, the Stirling power generation system further includes a power distribution module; The power distribution module includes a transmission line 1, a dual active bridge converter, a DC distribution network 5, a bidirectional DC-DC converter 7, and an energy storage battery 6; the dual active bridge converter includes a frequency converter 2, a high-frequency transformer 3, and a rectifier 4; The power transmission line 1 is connected to the linear motor mover 8-6 of the Stirling generator 8 to output the electrical energy generated by the Stirling generator 8. After the electrical energy is output, it is divided into two paths after passing through the frequency converter 2, the high-frequency transformer 3 and the rectifier 4. One path is output to the DC distribution network 5 to power the deep-sea equipment mounted on the DC distribution network 5. The other path is output to the energy storage battery 6 through the bidirectional DC-DC converter 7 for energy storage.

[0047] In a preferred embodiment of the present invention, the DC distribution network 5 uses DC power for power transmission, eliminating the need to consider phase synchronization and reactive power balance, thus improving the efficiency of power conversion. The dual active bridge converter enables electrical isolation between input and output, has high power density, and is easy to implement soft switching. The energy storage battery 6 stores excess energy when power demand is low and releases energy when power demand is high, thereby balancing load fluctuations.

[0048] In a preferred embodiment of the present invention, the deep-sea equipment mounted on the DC distribution network 5 may be deep-sea exploration equipment, deep-sea robots, oil and gas platforms, cables, mining equipment, communication equipment, and monitoring sensors, etc.

[0049] In a preferred embodiment of the present invention, see [reference needed]. Figure 2 The Stirling generator 8 includes a back pressure chamber 8-1, a valve distribution piston plate spring 8-2, a power piston plate spring 8-3, a cylinder 8-4, a linear motor end cover 8-5, a linear motor mover 8-6, a linear motor stator magnet 8-7, a linear motor stator 8-8, a cooler 8-9, a regenerator 8-10, a heater 8-11, a power piston 8-12, a valve distribution piston 8-13, a thermal insulation layer 9, a heat head 8-14, an expansion chamber 8-15, and a compression chamber 8-16.

[0050] The Stirling generator 8 is a closed-cycle external combustion generator that generates electricity by relying on the thermal expansion and contraction of the working fluid to drive the piston. Its core working principle is based on the Stirling thermodynamic cycle. An external heat source acts on the heat head 8-14, and the heat is introduced into the Stirling generator 8 through the heater 8-11. The working fluid expands in the expansion chamber 8-15, pushing the power piston 8-12 downwards against the force of its leaf spring. The linear motor mover 8-6, rigidly connected to the power piston 8-12, then moves linearly in the magnetic field formed by the stator magnet and the stator, cutting magnetic lines of force to generate an induced current. Electrical energy is output through the interface on the end cover. Simultaneously, the valve piston 8-13, under the action of the valve piston leaf spring 8-2, maintains a specific phase difference with the power piston 8-12, displacing the working fluid between the expansion chamber 8-15 and the compression chamber 8-16. As the working fluid flows through the regenerator 8-10 located between the hot and cold ends, it periodically stores and releases heat, achieving efficient heat energy recovery. The heat generated when the working fluid is compressed by the power piston 8-12 in the compression chamber 8-16 is carried away by the cooler 8-9. The entire gas replacement and power output process is completed in the cylinder 8-4. The back pressure chamber 8-1 is used to balance the back pressure of the valve timing piston 8-13, and the thermal insulation layer 9 is used to minimize the heat loss from the hot end to the environment and ensure cycle efficiency.

[0051] Heaters 8-11 in Stirling generator 8 absorb heat, which drives the piston to move in the form of pressure waves from the high-pressure gas. Excess heat is released through coolers 8-9. Stirling generator 8 completes one Stirling cycle through four processes: isothermal compression, isochoric heating, isothermal expansion, and isochoric cooling.

[0052] The deep-sea hydrothermal vent absorption heat pump driven Stirling power generation system of the present invention utilizes the heat pump heat exchange component 18 to provide a heat source for the Stirling generator 8 based on heat pump technology, and utilizes deep-sea cold water to provide a cold source for the cooler 8-9 of the Stirling generator 8. It drives the Stirling generator 8 by relying on the natural temperature difference of seawater, and has the advantages of no fuel supply, zero pollution, and high reliability, and strong adaptability to the extreme environment of the deep sea. The heat pump working fluid circulates and heats and releases heat within the heat pump, providing a continuous heat source for the system, thereby achieving continuous and green power generation and solving the power supply problem for deep-sea equipment.

[0053] A preferred embodiment of the present invention also provides a control method for a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump, used in the system of the present invention. The control method includes: It includes a main power generation control layer, a temperature and flow coordination control layer, and an execution equipment control layer. Control objectives include: Power balance: Ensures that the output power of the Stirling generator 8 matches the deep-sea load requirements and the status of the energy storage system.

[0054] Temperature stability: Maintain the hot end temperature of the Stirling generator 8 within the optimal operating range, while controlling the cold end temperature to ensure sufficient temperature difference and ensure efficient operation of the Stirling generator 8.

[0055] Pressure stabilization: Maintain the working fluid pressure inside the Stirling generator at the rated design value to ensure output power density.

[0056] System protection: Prevents equipment from overheating, overpressure, abnormal flow, etc., ensuring long-term reliable operation of the system.

[0057] (a) The main control layer for power generation includes: Control core: Bus voltage of DC distribution network 5 .

[0058] Control principle: The bus voltage of DC distribution network 5 is used as an indicator of the system power balance. If the voltage is stable at the rated value, it means that the power generation is balanced with the power consumption plus the charging power. If the voltage rises, it means that the power generation is excessive. If the voltage drops, it means that the power generation is insufficient or the load is increased.

[0059] Set the rated bus voltage of DC distribution network 5 and allowable fluctuation range Collect the bus voltage of DC distribution network 5. The bus voltage deviation is obtained based on the rated bus voltage and the bus voltage. The target power output of Stirling generator 8 is obtained based on the bus voltage deviation and allowable fluctuation range.

[0060] In a preferred embodiment of the present invention, obtaining the target power output value of the Stirling generator 8 based on the bus voltage deviation and the allowable fluctuation range includes: Define the bus voltage deviation as The allowable fluctuation range is Then it includes: when At that time, the Stirling power generation system is in equilibrium, and Stirling generator 8 maintains its current power output; when If the generator is over-generated, the bidirectional DC-DC converter 7 is controlled to store the excess power into the energy storage battery 6; if the energy storage battery 6 is full, the generator power of the Stirling generator 8 is reduced. when When it is determined that the power generation is insufficient or the load is increased, the energy storage battery 6 is controlled to discharge through the bidirectional DC-DC converter 7 to make up for the power shortage, and at the same time the power generation of the Stirling generator 8 is increased. In practice, the actual target power generation value is obtained. .

[0061] ; in, and These are the proportional and integral gains of the voltage loop controller, respectively. The system's base power setting is initialized based on historical operating data; t represents time.

[0062] (ii) The temperature and flow rate coordination control layer includes: This layer receives the target power generation from the main control layer. It is then broken down into control commands for the heat pump subsystem and the cooling circuit.

[0063] A. Hot-end temperature control loop based on feedforward-feedback composite control Control objective: Regulate the hot-junction temperature of Stirling generator 8. To stabilize it at the level that satisfies Required optimal temperature value .

[0064] Control variable: Set the opening degree of the first regulating valve 15 to regulate the flow rate of the heat pump working fluid entering the hot spring heat exchange component 18.

[0065] Based on the target power generation value By consulting the pre-calibrated power-temperature-flow rate table, the target flow rate of the first regulating valve 15 corresponding to the target power generation value can be obtained. The target temperature of the heat pump working fluid at the outlet of the hot spring heat exchanger assembly 18 The initial opening value of the first regulating valve 15 is obtained based on the target flow rate of the first regulating valve 15. The initial opening value is set to the first regulating valve 15.

[0066] ; in, The target flow rate for the first regulating valve 15, This is the maximum flow rate when the first regulating valve 15 is fully open.

[0067] The initial opening value is corrected based on the actual temperature and target temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component 18, including: The actual temperature of the heat pump working fluid at the outlet of the hot spring heat exchange component 18 is monitored in real time by temperature sensor 19. The temperature deviation is obtained based on the target temperature and the actual temperature. The opening correction value of the first regulating valve 15 is obtained based on the temperature deviation and the PID controller. The initial opening value is corrected based on the opening correction value to obtain the first opening value. The first opening value is then assigned to the first regulating valve 15.

[0068] ; ; in, , and These are the proportional, integral, and derivative gains of the temperature loop PID controller, respectively.

[0069] In a preferred embodiment of the present invention, if If the safety limit is exceeded, the system will execute override control, quickly reduce or close the first regulating valve 15, and trigger an alarm.

[0070] B. Cold end temperature control loop Control objective: Maintain the temperature of the cooling medium at the inlet of coolers 8-9 of the Stirling generator 8. At a stable, lower temperature.

[0071] Control variable: Set the second regulating valve to 25 degrees of opening to adjust the flow rate of the cooling medium.

[0072] The temperature at the inlet of heat exchange pipe 24 passing through cooler 8-9 in real time is recorded as the first temperature. ; the first temperature Compared with the first temperature setpoint By comparison, the cold end temperature deviation is obtained. The first temperature setpoint is set to be close to the temperature of deep-sea cold water; the second opening value is obtained based on the cold end temperature deviation and the PI controller. The second opening value is then assigned to the second regulating valve 25.

[0073] ; in, and These are the proportional and integral gains of the cooling temperature loop controller, respectively.

[0074] By changing the flow rate of the cooling medium flowing through the seawater cooling device 26, thereby... Stabilize the value near the set point to ensure the Stirling engine always has sufficient cooling capacity.

[0075] (iii) The execution equipment control layer includes: This layer is responsible for executing instructions from the upper layer and performing high-frequency device monitoring and protection.

[0076] Pump control: Pump 12, pump 14, and pump 27 usually operate at a constant speed to maintain the basic cycle, but can also be controlled to start and stop according to the system start-up and shutdown status or extreme operating conditions.

[0077] The air pressure control system monitors the pressure value of the power generation medium displayed on the pressure gauge 21 in real time. When the pressure is lower than the preset threshold, the solenoid valve on the air filling control branch 22 is automatically opened to replenish the power generation medium from the high-pressure gas cylinder 23 into the Stirling generator 8 until the pressure returns to normal and then the valve is closed.

[0078] Power conversion equipment control: Receives instructions from the external main control layer to control the operating mode, power transmission direction and magnitude of the dual active bridge converter and bidirectional DC-DC converter 7. The operating modes of the energy storage battery 6 include rectification mode and inverter mode, so as to achieve optimal energy management and transmission.

[0079] The method of this invention, through power balance control based on DC bus voltage and coordinated adjustment of heat pump working fluid flow rate and cooling working fluid flow rate, has the following advantages: Fast response: Feedforward control can quickly pre-adjust heat input according to power demand, overcoming the large inertial delay of the thermal system.

[0080] Precise and stable: Feedback PID control can eliminate feedforward errors and external disturbances, such as small fluctuations in hot spring temperature, ensuring precise and stable hot end temperature.

[0081] Global optimization: By controlling power generation, thermal management, power distribution and energy storage as a whole, the system's efficiency and operational safety are ensured under different operating conditions.

[0082] The control method for a Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump, based on the system of this invention, possesses the same beneficial effects. Furthermore, the method ensures that the output power of the Stirling generator 8 matches the deep-sea load demand and the energy storage system status, maintains the hot-end temperature of the Stirling generator 8 within its optimal operating range, and simultaneously controls the cold-end temperature to guarantee a sufficient temperature difference. This enables the system to operate efficiently, stably, and automatically under different heat source conditions and load demands, providing a stable and sustainable power guarantee for deep-sea equipment, and has excellent application value and prospects.

[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A Stirling power generation system driven by a deep-sea hydrothermal vent absorption heat pump, characterized by, The heat pump comprises a first liquid tank (13), a third pump (14), a hot spring heat exchange assembly (18), a condensing heat exchanger (10) and a condenser (11); The first liquid tank (13) is used for storing heat pump working medium; the third pump (14) is used for pumping heat pump working medium from the first liquid tank (13) and delivering the heat pump working medium to the hot spring heat exchange assembly (18); the hot spring heat exchange assembly (18) is used for heating the heat pump working medium by a deep-sea hot spring and delivering the heated heat pump working medium to the condensing heat exchanger (10); the heat pump working medium flows to the condenser (11) for condensation after heat release in the condensing heat exchanger (10); and the condensed heat pump working medium flows to the first liquid tank (13). The condensing heat exchanger (10) is arranged on a hot head (8-14) of the Stirling generator (8) and is used for conducting heat energy generated by heat release of the heat pump working medium to power generation working medium in the Stirling generator (8) for power generation.

2. The deep-sea hydrothermal vent absorption heat driven Stirling power generation system according to claim 1, characterized in that, The heat pump further comprises a first regulating valve (15), a temperature sensor (19) and a temperature control module (20); The first regulating valve (15) is arranged between the third pump (14) and the hot spring heat exchange assembly (18) and is used for regulating the flow of the heat pump working medium entering the hot spring heat exchange assembly (18); the temperature sensor (19) is arranged between the hot spring heat exchange assembly (18) and the condensing heat exchanger (10) and is used for monitoring the temperature of the heat pump working medium at the outlet of the hot spring heat exchange assembly (18); and the first regulating valve (15) and the temperature sensor (19) are both connected to the temperature control module (20), and the temperature control module (20) is used for changing the opening degree of the first regulating valve (15) according to the temperature of the heat pump working medium monitored by the temperature sensor (19).

3. The deep-sea hydrothermal vent absorption heat driven Stirling power generation system according to claim 2, characterized in that, The change of the opening degree of the first regulating valve (15) according to the temperature of the heat pump working medium monitored by the temperature sensor (19) comprises: When the temperature of the heat pump working medium at the outlet of the hot spring heat exchange assembly (18) monitored by the temperature sensor (19) is lower than a preset value, the temperature control module (20) reduces the opening degree of the first regulating valve (15) to reduce the flow and increase the temperature of the heat pump working medium at the outlet of the hot spring heat exchange assembly (18); and when the temperature of the heat pump working medium at the outlet of the hot spring heat exchange assembly (18) monitored by the temperature sensor (19) is higher than the preset value, the temperature control module (20) increases the opening degree of the first regulating valve (15) to increase the flow and reduce the temperature of the heat pump working medium at the outlet of the hot spring heat exchange assembly (18).

4. The deep-sea hydrothermal vent absorption heat pump driven Stirling power generation system according to claim 3, characterized in that, The heat pump further comprises a first pump (12); The first pump (12) is arranged between the condenser (11) and the first liquid tank (13) and is used for driving the heat pump working medium from the hot spring heat exchange assembly (18) to the condenser (11) to flow to the first liquid tank (13).

5. The deep-sea hydrothermal vent absorption heat pump driven Stirling power generation system according to claim 4, characterized in that, The Stirling generator system further comprises a cooling circuit; the cooling circuit comprises a second liquid tank (28), a second pump (27), a seawater cooling device (26), a second regulating valve (25) and a heat exchange pipeline (24). The second liquid storage tank (28) is used for storing cooling medium; the second pump (27) is used for driving the cooling medium in the cooling circuit to flow in the direction of the second liquid storage tank (28), the seawater cooling device (26), the second regulating valve (25), the heat exchange pipeline (24) and the second liquid storage tank (28); The heat exchange pipeline (24) is arranged at the cooler (8-9) of the Stirling generator (8), is used for absorbing the heat of the power generation medium in the Stirling generator (8), increasing the temperature difference between the hot end and the cold end of the Stirling generator (8), and dissipating the heat of the linear motor in the Stirling generator (8); the seawater cooling device (26) is used for absorbing the heat of the cooling medium in the cooling circuit by deep-sea cold water; the second regulating valve (25) is used for controlling the flow speed of the cooling medium in the heat exchange pipeline (24), so as to ensure that the temperature of the cooling medium flowing through the cooler (8-9) of the Stirling generator (8) is within a preset range.

6. The deep-sea hydrothermal vent absorption heat pump driven Stirling power generation system according to claim 5, characterized in that, The Stirling power generation system further comprises a gas pressure control module; the gas pressure control module comprises a pressure gauge (21), a gas charging control branch (22) and a high-pressure gas cylinder (23); The pressure gauge (21) is used for monitoring the gas pressure of the power generation medium in the Stirling generator (8), and when the gas pressure is lower than a preset value, the high-pressure gas cylinder (23) is driven through the gas charging control branch (22) to supplement the power generation medium into the Stirling generator (8).

7. The deep-sea hydrothermal vent absorption heat pump driven Stirling power generation system according to claim 6, characterized in that, The Stirling power generation system further comprises a power distribution module; The power distribution module comprises a power transmission line (1), a dual active bridge converter, a direct current distribution network (5), a bidirectional DC-DC converter (7) and an energy storage battery (6); the dual active bridge converter comprises a frequency converter (2), a high-frequency transformer (3) and a rectifier (4); The power transmission line (1) is connected to the linear motor rotor (8-6) of the Stirling generator (8), and is used for outputting the electric energy generated by the Stirling generator (8); after the electric energy is output, it is divided into two paths after passing through the frequency converter (2), the high-frequency transformer (3) and the rectifier (4), one path is output to the direct current distribution network (5) and is used for supplying power to the deep-sea equipment carried by the direct current distribution network (5), and the other path is output to the energy storage battery (6) through the bidirectional DC-DC converter (7) and is used for storing electric energy.

8. A control method for a deep-sea hydrothermal vent absorption heat pump driven Stirling power generation system for the system of claim 7, characterized in that, The control method comprises: setting the bus voltage rated value and the allowable fluctuation range of the direct current distribution network (5); acquiring the bus voltage of the direct current distribution network (5); obtaining the bus voltage deviation according to the bus voltage rated value and the bus voltage; obtaining the target power generation power value of the Stirling generator (8) according to the bus voltage deviation and the allowable fluctuation range; According to the target power generation power value, a pre-calibrated power-temperature-flow corresponding relationship table is queried to obtain a first regulating valve (15) target flow and a hot spring heat exchange component (18) outlet heat pump working medium target temperature corresponding to the target power generation power value; an opening degree initial value of the first regulating valve (15) is obtained according to the first regulating valve (15) target flow; the opening degree initial value is given to the first regulating valve (15), and the opening degree initial value is corrected based on an actual temperature of the hot spring heat exchange component (18) outlet heat pump working medium and the target temperature; The temperature of the heat exchange pipeline (24) flowing through the inlet end of the cooler (8-9) is monitored in real time, and is recorded as a first temperature; the first temperature is compared with a first temperature set value to obtain a cold end temperature deviation; the first temperature set value is set to be close to the deep sea cold water temperature; a second opening degree value is obtained according to the cold end temperature deviation combined with a PI controller, and the second opening degree value is given to the second regulating valve (25).

9. The control method of a deep-sea hydrothermal vent absorption heat driven Stirling power generation system according to claim 8, characterized by, The correction of the opening degree initial value based on the actual temperature of the hot spring heat exchange component (18) outlet heat pump working medium and the target temperature includes: The actual temperature of the hot spring heat exchange component (18) outlet heat pump working medium monitored by the temperature sensor (19) is collected in real time; a temperature deviation is obtained according to the target temperature and the actual temperature; an opening degree correction value of the first regulating valve (15) is obtained according to the temperature deviation combined with a PID controller; the opening degree initial value is corrected according to the opening degree correction value to obtain a first opening degree value, and the first opening degree value is given to the first regulating valve (15).

10. The control method of a deep-sea hydrothermal vent absorption heat driven Stirling power generation system according to claim 9, characterized by, According to the bus voltage deviation and the allowed fluctuation range, the target power generation power value of the Stirling generator (8) includes: defining the bus voltage deviation as , the allowable fluctuation range is then comprising: When the Stirling power system is in equilibrium, the Stirling engine (8) maintains the current power operation; When excess power is generated, the bidirectional DC-DC converter (7) is controlled to store the excess power in the energy storage battery (6); if the energy storage battery (6) is full, the power generation of the Stirling generator (8) is controlled to be reduced; When the power generation is insufficient or the load is increased, the control determines to discharge the energy storage battery (6) through the bidirectional DC-DC converter (7) to make up for the power shortage, while controlling to increase the power generation of the Stirling generator (8); In actual cases, the actual target power generation power value is obtained.

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