Pressure control method, device, equipment, medium and product of liquid hydrogen storage tank

Abstract

The application provides a pressure control method, device, equipment, medium and product of a liquid hydrogen storage tank. The method comprises the following steps: acquiring a current pressure in the liquid hydrogen storage tank; in response to the current pressure being greater than or equal to a first preset pressure threshold, starting a first thermoelectric power generation module to generate power by using a temperature difference between liquid hydrogen in the liquid hydrogen storage tank and a current environment; driving a refrigeration module by electric energy generated by the first thermoelectric power generation module to reliquefy liquid hydrogen evaporation gas generated by the liquid hydrogen storage tank to form liquid hydrogen to be recovered; and transmitting the liquid hydrogen to be recovered to the liquid hydrogen storage tank by a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, and the first thermoelectric power generation module is stopped; wherein the first preset pressure threshold is greater than the second preset pressure threshold. Thus, the temperature difference between the liquid hydrogen and the environment can be used to realize thermoelectric self-power supply, drive BOG reliquefaction recovery, reduce external power supply dependence and hydrogen emission, and realize stable closed-loop control of the storage tank pressure by double-threshold starting and stopping.

Description

Technical Field

[0001] This application relates to the field of thermal management technology, and in particular to a pressure control method, apparatus, equipment, medium and product for a liquid hydrogen storage tank. Background Technology

[0002] Due to the extremely low temperature of liquid hydrogen, it is difficult to completely prevent external heat from entering the storage tank during actual use. Affected by heat leakage, some of the liquid hydrogen inside the tank will evaporate and form liquid hydrogen vapor gas, leading to an increase in pressure inside the tank. Existing liquid hydrogen storage tanks typically control pressure through methods such as safety valve venting, active cooling and reliquefaction, or combustion. While safety valve venting is simple in structure, it results in hydrogen loss. Active cooling and reliquefaction can recover some hydrogen, but usually requires external energy input. Combustion can reduce tank pressure, but it consumes hydrogen and has corresponding safety management requirements. Summary of the Invention

[0003] This application aims to at least partially address one of the technical problems in the related art.

[0004] Therefore, the first objective of this application is to propose a pressure control method for liquid hydrogen storage tanks, which can utilize the temperature difference between liquid hydrogen and the environment to achieve thermoelectric self-powered operation, drive BOG reliquefaction and recovery, reduce dependence on external energy supply and hydrogen emissions, and achieve stable closed-loop control of storage tank pressure through dual-threshold start-stop.

[0005] The second objective of this application is to provide a pressure control device for a liquid hydrogen storage tank.

[0006] The third objective of this application is to propose an electronic device.

[0007] The fourth objective of this application is to provide a computer-readable storage medium.

[0008] The fifth objective of this application is to provide a computer program product.

[0009] To achieve the above objectives, a first aspect of this application proposes a pressure control method for a liquid hydrogen storage tank, comprising: acquiring the current pressure inside the liquid hydrogen storage tank; responding to the current pressure being greater than or equal to a first preset pressure threshold, activating a first thermoelectric power generation module to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment; using the electrical energy generated by the first thermoelectric power generation module to drive a refrigeration module to reliquefy the liquid hydrogen vaporized gas generated in the liquid hydrogen storage tank to form liquid hydrogen to be recovered; and transferring the liquid hydrogen to be recovered to the liquid hydrogen storage tank through a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down; wherein the first preset pressure threshold is greater than the second preset pressure threshold.

[0010] According to the pressure control method for a liquid hydrogen storage tank according to an embodiment of this application, the current pressure inside the liquid hydrogen storage tank is first obtained. Then, in response to the current pressure being greater than or equal to a first preset pressure threshold, a first thermoelectric power generation module is activated to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. Next, the electrical energy generated by the first thermoelectric power generation module drives a refrigeration module to reliquefy the liquid hydrogen vapor produced in the liquid hydrogen storage tank to form liquid hydrogen to be recovered. Finally, the liquid hydrogen to be recovered is transferred to the liquid hydrogen storage tank through a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down. The first preset pressure threshold is greater than the second preset pressure threshold. Thus, the temperature difference between liquid hydrogen and the environment can be used to achieve thermoelectric self-powered operation, driving the reliquefaction and recovery of BOG (Bottle-Off Gas), reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of the storage tank pressure through dual-threshold start-stop.

[0011] In addition, the pressure control method for liquid hydrogen storage tanks according to the above embodiments of this application may also have the following additional technical features: In one embodiment of this application, in response to the current pressure being greater than or equal to a first preset pressure threshold, the method further includes: generating a pressure warning signal for the liquid hydrogen storage tank based on the current pressure, and sending the pressure warning signal to the second thermoelectric power generation module; adjusting the power generation capacity of the second thermoelectric power generation module based on the pressure warning signal, wherein the second thermoelectric power generation module generates electricity using the temperature difference between the liquid hydrogen and the fuel cell stack coolant.

[0012] In one embodiment of this application, after the current pressure is less than or equal to a second preset pressure threshold, the method further includes: controlling the second thermoelectric power generation module to restore normal power generation.

[0013] In one embodiment of this application, the method further includes: acquiring the rate of change of the current pressure inside the liquid hydrogen storage tank; and adjusting the rate of reliquefaction of the liquid hydrogen vaporized gas using a refrigeration module based on the rate of change and a preset micro-control algorithm.

[0014] In one embodiment of this application, in response to the failure to start the first thermoelectric power generation module, a corresponding alarm message is generated and sent to the corresponding target terminal; the cooling module is driven by an external power supply or the electrical energy generated by the second thermoelectric power generation module to reliquefy the liquid hydrogen vaporized gas generated by the liquid hydrogen storage tank to form liquid hydrogen to be recovered.

[0015] To achieve the above objectives, a second aspect of this application provides a pressure control device for a liquid hydrogen storage tank, comprising: a first acquisition module for acquiring the current pressure inside the liquid hydrogen storage tank; a power generation module for activating a first thermoelectric power generation module to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment in response to the current pressure being greater than or equal to a first preset pressure threshold; a reliquefaction module for driving a refrigeration module to reliquefy the liquid hydrogen vaporized gas generated in the liquid hydrogen storage tank using the electrical energy generated by the first thermoelectric power generation module, to form liquid hydrogen to be recovered; and a control module for transferring the liquid hydrogen to be recovered to the liquid hydrogen storage tank through a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down, wherein the first preset pressure threshold is greater than the second preset pressure threshold.

[0016] According to the pressure control device for a liquid hydrogen storage tank according to an embodiment of this application, the current pressure inside the liquid hydrogen storage tank is first acquired by a first acquisition module. Then, in response to the current pressure being greater than or equal to a first preset pressure threshold, a power generation module activates a first thermoelectric power generation module to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. Next, a reliquefaction module uses the electrical energy generated by the first thermoelectric power generation module to drive a refrigeration module to reliquefy the liquid hydrogen vapor produced in the liquid hydrogen storage tank, forming liquid hydrogen to be recovered. Finally, a control module transmits the liquid hydrogen to be recovered to the liquid hydrogen storage tank through a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down. The first preset pressure threshold is greater than the second preset pressure threshold. Thus, the temperature difference between liquid hydrogen and the environment can be used to achieve thermoelectric self-powered operation, driving the reliquefaction and recovery of BOG (Bottle-Off Gas), reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of the storage tank pressure through dual-threshold start-stop.

[0017] In addition, the pressure control device for the liquid hydrogen storage tank according to the above embodiments of this application may also have the following additional technical features: In one embodiment of this application, the power generation module is further configured to: in response to the current pressure being greater than or equal to a first preset pressure threshold, generate a pressure warning signal for the liquid hydrogen storage tank based on the current pressure, and send the pressure warning signal to the second thermoelectric power generation module; adjust the power generation power of the second thermoelectric power generation module according to the pressure warning signal, wherein the second thermoelectric power generation module generates power using the temperature difference between the liquid hydrogen and the fuel cell stack coolant.

[0018] To achieve the above objectives, a third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements any of the above-described pressure control methods for liquid hydrogen storage tanks.

[0019] The electronic device according to the embodiments of this application implements any of the above-mentioned pressure control methods for liquid hydrogen storage tanks when the processor executes a computer program. It realizes the thermoelectric self-powered operation by utilizing the temperature difference between liquid hydrogen and the environment to drive the BOG reliquefaction and recovery, reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of storage tank pressure through dual-threshold start-stop.

[0020] To achieve the above objectives, a fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the pressure control method for a liquid hydrogen storage tank as described above.

[0021] According to the embodiments of this application, a computer-readable storage medium storing a computer program thereon implements any of the above-mentioned pressure control methods for liquid hydrogen storage tanks when executed by a processor. This method utilizes the temperature difference between liquid hydrogen and the environment to achieve thermoelectric self-powered operation, driving BOG reliquefaction and recovery, reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of storage tank pressure through dual-threshold start-stop.

[0022] To achieve the above objectives, a fifth aspect of this application provides a computer program product, including a computer program that, when executed by a processor, implements the pressure control method for a liquid hydrogen storage tank as described above.

[0023] The computer program product according to the embodiments of this application implements any of the above-mentioned pressure control methods for liquid hydrogen storage tanks when the computer program is executed. It realizes the use of the temperature difference between liquid hydrogen and the environment to achieve thermoelectric self-powered power supply, drive BOG reliquefaction and recovery, reduce external energy supply dependence and hydrogen emissions, and achieve stable closed-loop control of storage tank pressure through dual threshold start-stop.

[0024] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0025] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a schematic flowchart of a pressure control method for a liquid hydrogen storage tank according to some embodiments of this application; Figure 2 This is a schematic diagram of the overall architecture of a liquid hydrogen storage tank pressure control system according to an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a second thermoelectric power generation module according to an embodiment of this application; Figure 4 This is a schematic flowchart of a pressure control method for a liquid hydrogen storage tank according to a specific embodiment of this application; Figure 5 This is a block diagram of a pressure control device for a liquid hydrogen storage tank according to some embodiments of this application; Figure 6 This is a schematic diagram of the structure of an electronic device according to some embodiments of this application. Detailed Implementation

[0026] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0027] The pressure control method, apparatus, equipment, medium, and product of liquid hydrogen storage tank according to embodiments of this application are described below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, the pressure control method for a liquid hydrogen storage tank according to an embodiment of this application may include the following steps: Step S1: Obtain the current pressure inside the liquid hydrogen storage tank.

[0029] Specifically, the pressure state of the liquid hydrogen storage tank is determined by acquiring the current pressure inside the tank. As a preferred example, a pressure detection element can be installed on the liquid hydrogen storage tank or on the pipeline connected to it. This element collects the pressure signal from the tank and sends it to a pressure controller. The pressure controller then determines the current pressure inside the tank based on the received signal. The pressure detection element can be a pressure sensor, pressure transmitter, or other detection device capable of detecting the pressure of the liquid hydrogen storage tank. The current pressure can be a real-time acquired pressure value or a pressure value obtained after processing pressure signals acquired within a preset time period.

[0030] Step S2: In response to the current pressure being greater than or equal to a first preset pressure threshold, the first thermoelectric power generation module is activated to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. The first preset pressure threshold can be calibrated according to actual conditions.

[0031] Specifically, after obtaining the current pressure inside the liquid hydrogen storage tank, the current pressure is compared with a first preset pressure threshold. The first preset pressure threshold characterizes the upper pressure limit requiring pressure regulation in the liquid hydrogen storage tank, and its specific value can be set according to the design pressure, operating pressure range, and safety control requirements of the liquid hydrogen storage tank. Preferably, the first preset pressure threshold can be set to 0.9 MPa. When the current pressure is greater than or equal to the first preset pressure threshold, it indicates that the pressure inside the liquid hydrogen storage tank has reached a state requiring regulation. At this time, a start command is generated, and the first thermoelectric power generation module is started according to the start command.

[0032] The first thermoelectric power generation module generates electricity by utilizing the temperature difference between liquid hydrogen in a liquid hydrogen storage tank and the current environment. Specifically, the liquid hydrogen in the tank is at a low temperature, while the current ambient temperature is higher than that of the liquid hydrogen, creating a temperature difference. The first thermoelectric power generation module exchanges heat with the liquid hydrogen in the tank or with a part related to the cooling capacity of the tank through its cold end, and with the current environment through its hot end. This creates a temperature difference between the hot and cold ends of the first thermoelectric power generation module, enabling it to output electrical energy based on thermoelectric conversion. The current environment can be the natural environment outside the vehicle, site, or equipment where the liquid hydrogen storage tank is located, or the surrounding space that can serve as a heat source.

[0033] It should be noted that, as Figure 2 As shown, the first thermoelectric power generation module is in contact with both the outer wall of the hydrogen storage container and the ambient air, generating electricity using the temperature difference between the hydrogen storage container and the ambient air. Optionally, the liquid hydrogen storage tank also includes a hydrogen storage container disposed inside the liquid hydrogen storage tank body, wherein the first thermoelectric power generation module is in contact with both the outer wall of the hydrogen storage container and the ambient air, generating electricity using the temperature difference between the hydrogen storage container and the ambient air.

[0034] In this application, ambient air refers to the natural gaseous medium surrounding the liquid hydrogen storage tank, representing the external heat source environment that provides heat exchange conditions at the high-temperature end; temperature difference refers to the temperature difference formed between the outer wall of the hydrogen storage container and the ambient air, representing the thermal driving force conditions that drive the first thermoelectric power generation module to perform energy conversion; and the outer wall of the hydrogen storage container is the contact surface between the hydrogen storage container and the external structure, representing the low-temperature heat source interface for heat exchange at the cold end of the first thermoelectric power generation module.

[0035] To further illustrate the technical solution of this application, the numerical values ​​set in the following embodiments are only preferred embodiments and are used to illustrate this application, and do not constitute a limitation on the scope of protection.

[0036] The liquid hydrogen storage tank includes a tank body and a storage container inside the tank body. The storage container stores liquid hydrogen and has an operating temperature of -253℃ and an operating pressure of 0.3MPa-1.0MPa, with an optimal operating pressure range of 0.5MPa-0.9MPa to meet the liquid hydrogen storage requirements of hydrogen refueling stations. The tank body adopts a multi-layer structure design, including, from the inside out, a storage container, a vacuum insulation layer, a flexible thermoelectric membrane, and an outer shell. The storage container, in addition to storing liquid hydrogen, also receives the reflux of liquefied hydrogen after processing by the refrigeration module, enabling the recovery and reuse of evaporated hydrogen and maintaining the pressure inside the storage container within the target pressure range.

[0037] It is understood that by setting multiple insulation layers between the outer wall of the hydrogen storage container and the inner wall of the liquid hydrogen storage tank and forming a vacuum insulation layer, this application can effectively reduce the rate of heat transfer from the outside to the hydrogen storage container, significantly reduce the amount of hydrogen vaporized due to heat leakage, thereby reducing the rate of pressure rise inside the storage tank, and at the same time improving the overall insulation performance and cryogenic maintenance capability of the storage tank.

[0038] Vacuum insulation layers are used to reduce the rate at which external heat is transferred to the hydrogen storage container, thereby reducing the heat leakage rate.

[0039] The first thermoelectric power generation module includes a cold end and a hot end. The cold end of the first thermoelectric power generation module is in contact with the outer wall of the hydrogen storage container, and the hot end of the first thermoelectric power generation module is exposed to the ambient air. It generates electricity by utilizing the temperature difference between the hydrogen storage container and the ambient air.

[0040] The cold end is the end structure in the first thermoelectric power generation module that exchanges heat with the low-temperature side, and in this application, it represents the side that is in contact with the outer wall of the hydrogen storage container and obtains a low-temperature heat source; the hot end is the end structure in the first thermoelectric power generation module that exchanges heat with the high-temperature side, and in this application, it represents the side that is exposed to ambient air and obtains a high-temperature heat source.

[0041] Understandably, this application enables the first thermoelectric power generation module to stably utilize the temperature difference between the low-temperature side of the hydrogen storage container and the high-temperature side of the ambient air to achieve continuous power output. At the same time, it recovers and utilizes the temperature difference energy that was originally lost during the operation of the storage tank, thereby improving energy utilization efficiency. Furthermore, this application can generate electricity without additional external energy input, which helps to reduce system operating costs and improve the energy self-sufficiency and overall operational stability of the liquid hydrogen storage tank system.

[0042] In this embodiment, the cold end is in close contact with the outer wall of the hydrogen storage container through a highly thermally conductive material to obtain the low-temperature end temperature from the hydrogen storage container. The hot end of the first thermoelectric power generation module uses the outer side of the power generation unit as the hot surface, and is directly exposed to the ambient air for heat exchange, thereby forming the high-temperature end of the first thermoelectric power generation module. Its operating temperature varies with the ambient temperature, ranging from -40°C to 50°C. Ultimately, a temperature difference power generation condition is formed between the cold and hot ends, with a temperature difference range of approximately 290°C.

[0043] The cold end of the first thermoelectric power generation module is connected to the outer wall of the hydrogen storage container through a heat-conducting component to achieve heat transfer between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container.

[0044] In terms of electrical connection, the electrodes at both ends of the hot end of the first thermoelectric power generation module are electrically connected to copper foil through low-temperature conductive adhesive. The electrical connection forms a series structure, and parallel current merging is performed on the electrical connection line as needed. Finally, the power is led out to the management unit through the transmission line (such as a flexible low-temperature cable) to output stable DC power.

[0045] This application utilizes the natural temperature difference between liquid hydrogen and the environment to generate electricity, providing all the electrical energy for cooling evaporated hydrogen to liquefy hydrogen, eliminating the need for external power supply, completely solving the high energy consumption problem of related technologies, and achieving near-zero operating costs.

[0046] A heat-conducting component is provided between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container to transfer heat between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container.

[0047] The heat-conducting component is a heat-conducting medium or structure disposed between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container. In this application, it represents a heat transfer medium component used to enhance the heat transfer efficiency between the cold end and the outer wall of the hydrogen storage container and reduce the contact thermal resistance.

[0048] It is understood that by providing a heat-conducting component between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container, the contact thermal resistance between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container can be reduced, thereby improving the heat transfer efficiency and enabling the cold end to more fully obtain the low-temperature heat from the hydrogen storage container. This improves the temperature difference utilization efficiency and output stability of the first thermoelectric power generation module. At the same time, it is beneficial to improve the overall temperature difference power output capability, enhance the system energy recovery efficiency, and further improve the power supply guarantee capability and system operation stability of the management unit and the refrigeration module.

[0049] The heat-conducting component is used to transfer heat between the cold end of the first thermoelectric power generation module and the outer wall of the hydrogen storage container, thereby reducing the contact thermal resistance between the two and improving the thermal conductivity. The heat-conducting component can be implemented using low-temperature high thermal conductivity silicone grease or thermal adhesive (in one embodiment of this application, the thermal conductivity of the low-temperature high thermal conductivity silicone grease or thermal adhesive is not less than 4 W / m·K and can withstand a low temperature environment of -260℃). The cold end is attached to the outer wall of the hydrogen storage container by the low-temperature high thermal conductivity silicone grease or thermal adhesive, and is externally clamped in sections with stainless steel clamps to achieve low thermal resistance, gapless and uniform tight contact between the cold end and the outer wall of the hydrogen storage container, thereby ensuring that the cold end can be stably maintained in the working environment condition of -253℃. Furthermore, the thermally conductive connection between the cold end and the outer wall of the hydrogen storage container can also be achieved by covering the outer wall of the hydrogen storage container with 0.1-0.2mm high-purity copper foil or aluminum foil, so that the cold side of the first thermoelectric power generation module is directly attached to the metal foil layer, or by using vacuum adsorption bonding method, the first thermoelectric power generation module is tightly attached to the outer wall of the hydrogen storage container through negative pressure, so as to improve the bonding tightness and thermal conductivity.

[0050] Optionally, the first thermoelectric power generation module includes at least one power generation unit, each power generation unit being connected to a cold end and a hot end, and adjacent power generation units being connected in series and / or in parallel on the transmission line.

[0051] Among them, the generator unit is the basic power generation functional module that constitutes the first thermoelectric power generation module. In this application, it represents the smallest first thermoelectric power generation module that independently completes thermoelectric conversion and outputs electrical energy. The transmission line is the power transmission channel used to transmit the electrical energy output by the generator unit. In this application, it represents the electrical connection path that collects the electrical energy of each generator unit and outputs it to the management unit.

[0052] It is understood that by setting at least one power generation unit and connecting each power generation unit to the cold end and the hot end respectively, the distributed utilization of the temperature difference between the hydrogen storage container and the ambient air can be realized. At the same time, by connecting adjacent power generation units in series and / or parallel on the transmission line, the output voltage and current characteristics can be flexibly adjusted, thereby improving the power supply matching capability and system stability.

[0053] In this embodiment, each power generation unit is connected to a cold end and a hot end to convert temperature difference into electrical energy. The power generation unit is made of a flexible thermoelectric thin film and is uniformly attached to the outer wall of the liquid hydrogen storage tank at 360°, covering the side wall and the top dome area of ​​the tank, so as to make full use of the temperature difference between the outer wall of the storage tank and the environment to generate electricity. The flexible structure can adapt to the curved surface of cylindrical or spherical storage tanks and can be installed without additional supports.

[0054] In terms of layout, the power generation unit is used to form a covered power generation array on the outer wall of the storage tank, and its layout structure can be realized by adopting different arrangement forms as needed. The power generation unit can be arranged in segments along the axial direction of the storage tank. Each segment is formed by splicing multiple sub-modules to form a ring structure along the circumference. Adjacent ring structures are connected in series and / or parallel, and finally converge to the transmission line, thus forming a full-circumference power generation array covering the outer wall of the storage tank. In addition to the 360° uniform fit arrangement, a ring-shaped segmented overlapping arrangement can also be adopted. In this arrangement, several ring segments are divided along the axial direction of the storage tank, each segment being 200-300mm high. Each ring is formed by splicing arc-shaped sub-modules to form a complete circle. The sides of adjacent sub-modules overlap by 5-10mm to eliminate gaps. The rings are connected along the axial direction in series and / or parallel to form a full-circumference power generation array. Alternatively, a spiral winding arrangement can be adopted. Flexible thermoelectric film modules are spirally wound along the outer wall of the storage tank at a winding angle of 15°-30°. Adjacent winding rings are parallel and fit together without gaps, covering the entire circumference and side walls of the tank, and the power is drawn out through the beginning and end ends to form a continuous power generation circuit.

[0055] In terms of splicing method, each power generation unit is formed by multiple arc-shaped sub-modules overlapping each other along the circumference to form a closed ring. The sides of adjacent sub-modules overlap by 5-8mm and are fixed by low-temperature conductive adhesive and stainless steel pressure strips to ensure continuous conductivity and no gaps at the joints. The axial adjacent rings are connected in series or in parallel through flexible low-temperature copper leads, thus forming a full-circumference power generation array.

[0056] In terms of performance parameters, the power density of the power generation unit is 50-100W / ㎡ under a temperature difference ΔT of 290℃, and the total power generation can reach hundreds of watts to thousands of watts when arranged around the perimeter, so as to meet the 12-24V DC drive requirements of the micro chiller.

[0057] In terms of module connection, the power generation unit adopts a series-parallel combination connection method to match the driving voltage requirements of the micro chiller and provide redundant power supply capability. When some power generation units fail, it will not affect the normal operation of the overall power generation system.

[0058] In terms of core advantages, the power generation unit adopts a full-circle arrangement to maximize the utilization of the heat dissipation surface area of ​​the storage tank and improve the efficiency of cold energy utilization. At the same time, the flexible structure has good surface adaptability, no moving parts, high reliability, and a service life of more than 10 years, which matches the service life of the storage tank, achieving maintenance-free operation.

[0059] Optionally, the electron-generating unit includes at least one flexible thermoelectric film, wherein the flexible thermoelectric film is circumferentially attached to the outer wall surface of the liquid hydrogen storage tank body.

[0060] Among them, the flexible thermoelectric film is a thin-film power generation material that can be bent and realize thermoelectric conversion. In this application, it represents a flexible power generation element used to convert the temperature difference between the hydrogen storage container and the ambient air into electrical energy. The circumferential bonding is an arrangement in which the flexible thermoelectric film continuously or segmentally covers the outer wall of the liquid hydrogen storage tank. In this application, it represents a structural installation method that realizes the utilization of the temperature difference of the outer wall of the storage tank.

[0061] It is understood that by attaching the flexible thermoelectric film along the outer wall of the liquid hydrogen storage tank in the circumferential direction, the embodiment of this application can make full use of the temperature gradient in the circumferential direction of the storage tank, thereby expanding the effective power generation area and improving the overall thermoelectric power output. At the same time, the flexible structure can well adapt to the curved shape of the storage tank, reduce installation gaps and structural stress concentration, and improve the tightness of the fit and heat exchange efficiency.

[0062] Preferably, the power generation unit includes at least one flexible thermoelectric film, which is circumferentially attached to the outer wall of the liquid hydrogen storage tank and can form a 360° full circumferential coverage along the outer wall, thereby fully utilizing the temperature difference between the outer wall of the tank and the environment to generate electricity. The flexible thermoelectric film is preferably disposed within the integrated layer between the vacuum insulation layer and the outer shell, and is continuously attached to the tank circumferentially to maximize coverage of the heat dissipation surface of the outer wall of the tank. Due to its excellent flexibility, the flexible thermoelectric film can adapt to the curved surface structure of cylindrical or spherical storage tanks, and is characterized by its small size, light weight, and absence of moving parts, thereby improving the overall structural reliability and making it suitable for small and medium-sized liquid hydrogen storage tanks of different specifications.

[0063] Optionally, the collection unit is a gas collection structure for collecting evaporated hydrogen from the hydrogen storage container, representing a centralized collection and transportation channel for evaporated hydrogen in this application. The collection unit includes a collection chamber and a pressure buffer structure disposed within the collection chamber. One end of the collection chamber is connected to the hydrogen storage container of the liquid hydrogen storage tank via a first pipeline, and the other end of the collection chamber is connected to the input end of the refrigeration module via a second pipeline. The output end of the refrigeration module is connected to the hydrogen storage container of the liquid hydrogen storage tank via a third pipeline.

[0064] Optionally, the management unit includes a rectifier, a voltage regulator, and an energy storage module. The input terminal of the rectifier is connected to the transmission line of the first thermoelectric power generation module, the output terminal of the rectifier is connected to the input terminal of the voltage regulator, the output terminal of the voltage regulator is connected to the energy storage module, and the energy storage module is connected to the cooling module and the control unit through power supply links. The electrical energy of the transmission line is processed by the rectifier and the voltage regulator to obtain DC power, which is stored by the energy storage module.

[0065] The rectifier is a power conversion device used to convert the AC or unstable electrical energy output from the first thermoelectric power generation module into DC electrical energy. In this application, it represents a power conversion module that rectifies the electrical energy output from the first thermoelectric power generation module. The voltage regulator is a power regulation device used to regulate the voltage of the rectified DC power. In this application, it represents a power regulation unit that stabilizes the output voltage. The energy storage module is an energy storage device used to store DC electrical energy and supply power to an external load. In this application, it represents an energy buffer and power supply unit that provides stable power to the cooling module and control unit.

[0066] It is understood that, by setting up a management unit consisting of a rectifier, a voltage regulator, and an energy storage module, the fluctuating electrical energy output from the first thermoelectric power generation module can be rectified and stabilized to convert it into a stable DC output, thereby improving power quality and power supply stability. At the same time, by buffering and allocating electrical energy through the energy storage module, continuous power supply capability can be provided when the power generation fluctuates or the load changes suddenly, avoiding the interruption of operation of the cooling module due to unstable power supply. Furthermore, this structure can realize the coordinated management of power generation, energy storage, and power supply, improving the system's energy utilization efficiency and power supply reliability.

[0067] The input terminal of the rectifier is connected to the transmission line of the first thermoelectric power generation module to rectify the electrical energy output by the first thermoelectric power generation module, converting the unstable electrical energy output by the flexible thermoelectric thin film module array into direct current. The output terminal of the rectifier is connected to the input terminal of the voltage regulator, which is used to regulate the voltage of the rectified electrical energy, converting it into stable 12-24V direct current. The output terminal of the voltage regulator is connected to the energy storage module, which is used to store stable direct current and perform short-term energy buffering to provide continuous power supply for the system when the power generation fluctuates. The energy storage module is connected to the cooling module and the control unit through power supply links, thereby providing stable and continuous electrical energy input to the cooling module and the control unit.

[0068] Step S3: The electrical energy generated by the first thermoelectric power generation module drives the refrigeration module to reliquefy the liquid hydrogen vaporized gas generated by the liquid hydrogen storage tank to form liquid hydrogen to be recovered.

[0069] Specifically, after the first thermoelectric power generation module starts up and outputs electrical energy, the electrical energy is supplied to the refrigeration module. The refrigeration module operates under the drive of electrical energy to cool the liquid hydrogen vapors generated by heat leakage in the liquid hydrogen storage tank, causing the liquid hydrogen vapors to change from a gaseous state back into a liquid state, thereby forming liquid hydrogen to be recovered.

[0070] In some embodiments, the liquid hydrogen vapor produced by the liquid hydrogen storage tank can enter the refrigeration module via a gas outlet channel connected to the liquid hydrogen storage tank. The refrigeration module may include refrigeration components capable of cryogenic cooling or reliquefaction, and its specific structure can be configured according to the capacity of the liquid hydrogen storage tank, the amount of liquid hydrogen vapor produced, and pressure control requirements. Preferably, the operating power of the refrigeration module can be matched with the output power of the first thermoelectric power generation module, so that the power generated by the first thermoelectric power generation module can be used to drive the refrigeration module to reliquefy the liquid hydrogen vapor. By reliquefying the liquid hydrogen vapor into recoverable liquid hydrogen, the content of gaseous hydrogen in the liquid hydrogen storage tank can be reduced, providing conditions for subsequent pressure reduction in the liquid hydrogen storage tank.

[0071] Step S4: The liquid hydrogen to be recovered is transferred to the liquid hydrogen storage tank through the liquid hydrogen recovery module until the current pressure is less than or equal to the second preset pressure threshold, at which point the first thermoelectric power generation module is shut down; wherein the first preset pressure threshold is greater than the second preset pressure threshold. The second preset pressure threshold can be calibrated according to actual conditions.

[0072] Specifically, after the refrigeration module reliquefies the evaporated liquid hydrogen gas to form liquid hydrogen to be recovered, the liquid hydrogen recovery module transfers the liquid hydrogen to be recovered to the liquid hydrogen storage tank. The liquid hydrogen recovery module may include a return pipeline, a return valve, or other components capable of realizing liquid hydrogen return connected to the refrigeration module and the liquid hydrogen storage tank. As the liquid hydrogen to be recovered is transferred back to the liquid hydrogen storage tank, the gaseous hydrogen content in the liquid hydrogen storage tank decreases, and the pressure in the storage tank gradually decreases. The current pressure in the liquid hydrogen storage tank is continuously acquired and compared with a second preset pressure threshold. The second preset pressure threshold is used to characterize the stopping pressure of the pressure regulation process. Its specific value can be calibrated according to the working pressure range of the liquid hydrogen storage tank, safety control requirements, and the operating conditions of the storage tank. Preferably, the second preset pressure threshold can be set to 0.7 MPa.

[0073] When the current pressure is less than or equal to the second preset pressure threshold, it indicates that the pressure inside the liquid hydrogen storage tank has dropped to the preset range. A shutdown command is generated, and the first thermoelectric power generation module is shut down according to the command. Correspondingly, the first thermoelectric power generation module stops supplying power to the refrigeration module, and the refrigeration module stops reliquefying the evaporated liquid hydrogen gas. Because the first preset pressure threshold is greater than the second preset pressure threshold, the first thermoelectric power generation module starts when the current pressure reaches the higher pressure threshold and shuts down when the current pressure drops to the lower pressure threshold. This creates a pressure control process with start-stop hysteresis, preventing the first thermoelectric power generation module from frequently starting and stopping near a single pressure threshold, thus improving the stability of the liquid hydrogen storage tank pressure control.

[0074] This embodiment first acquires the current pressure inside the liquid hydrogen storage tank. Then, in response to the current pressure being greater than or equal to a first preset pressure threshold, it activates a first thermoelectric power generation module to generate electricity using the temperature difference between the liquid hydrogen in the tank and the ambient environment. Next, the electricity generated by the first thermoelectric power generation module drives a refrigeration module to reliquefy the evaporated liquid hydrogen from the tank, forming liquid hydrogen to be recovered. Finally, the liquid hydrogen to be recovered is transferred back to the liquid hydrogen storage tank via a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down. The first preset pressure threshold is greater than the second preset pressure threshold. Thus, the temperature difference between liquid hydrogen and the environment enables thermoelectric self-powering to drive the reliquefaction and recovery of BOG (Bottle-Off Gas), reducing dependence on external energy supply and hydrogen emissions. Furthermore, the dual-threshold start-stop mechanism achieves stable closed-loop control of the storage tank pressure.

[0075] In some embodiments of this application, in response to the current pressure being greater than or equal to a first preset pressure threshold, the method further includes: generating a pressure warning signal for the liquid hydrogen storage tank based on the current pressure, and sending the pressure warning signal to the second thermoelectric power generation module; adjusting the power generation capacity of the second thermoelectric power generation module based on the pressure warning signal, wherein the second thermoelectric power generation module generates electricity using the temperature difference between the liquid hydrogen and the fuel cell stack coolant.

[0076] Specifically, the second thermoelectric power generation module can be a thermoelectric power generation module located between the liquid hydrogen supply path and the fuel cell stack coolant circuit. The second thermoelectric power generation module generates electricity using the temperature difference between the liquid hydrogen and the stack coolant, and can output electrical energy during the vaporization or heat exchange of the liquid hydrogen. Preferably, this second thermoelectric power generation module can be used as a cold energy utilization module in the thermal management system of a fuel cell commercial vehicle.

[0077] When the current pressure is greater than or equal to a first preset pressure threshold, in addition to activating the first thermoelectric power generation module, a pressure warning signal for the liquid hydrogen storage tank can be generated based on the current pressure. The pressure warning signal indicates that the liquid hydrogen storage tank is currently under high pressure. The pressure warning signal may include the current pressure value or a status indicator indicating that the pressure has reached or exceeded the first preset pressure threshold. The pressure warning signal can be sent to the second thermoelectric power generation module or a control unit for controlling the second thermoelectric power generation module via vehicle control bus, communication harness, or other signal transmission methods. Upon receiving the pressure warning signal, the second thermoelectric power generation module adjusts its power generation capacity accordingly.

[0078] In some embodiments, adjusting the power output of the second thermoelectric power generation module may include reducing its power output. Since the second thermoelectric power generation module generates electricity using the temperature difference between liquid hydrogen and the stack coolant, its power generation process is related to the supply, heat exchange, or vaporization of liquid hydrogen. When the liquid hydrogen storage tank is under high pressure, reducing the power output of the second thermoelectric power generation module can correspondingly reduce its demand for liquid hydrogen supply or heat exchange, minimizing the impact on the operating status of the liquid hydrogen storage tank, thereby giving higher priority to the pressure regulation process of the liquid hydrogen storage tank. In some embodiments, the second thermoelectric power generation module may also adjust its power output to a preset power range based on a pressure warning signal, or reduce its power output according to a preset power adjustment ratio.

[0079] Therefore, when the pressure in the liquid hydrogen storage tank reaches the first preset pressure threshold, the second thermoelectric power generation module, which generates electricity by utilizing the temperature difference between liquid hydrogen and the stack coolant, can adjust its power according to the pressure warning signal while the pressure regulation on the storage tank side is activated. This achieves coordinated control between the liquid hydrogen storage tank pressure control and the liquid hydrogen cold energy power generation process.

[0080] It should be noted that, as Figure 3 As shown, the second thermoelectric power generation module may include: a liquid hydrogen flow channel 1, a first thermally conductive substrate 2, a thermoelectric component, a second thermally conductive substrate 4, and a coolant flow channel 5. The first thermally conductive substrate 2 connects the outer wall of the liquid hydrogen flow channel 1 to one side of the thermoelectric component; the second thermally conductive substrate 4 connects the outer wall of the coolant flow channel 5 to the other side of the thermoelectric component; the thermoelectric component transfers heat between the liquid hydrogen flow channel 1 and the coolant flow channel 5, and generates electricity based on the temperature difference between the liquid hydrogen flow channel 1 and the coolant flow channel 5.

[0081] The second thermoelectric power generation module is mainly used to receive cryogenic liquid hydrogen and high-temperature coolant, and to complete the gasification and power generation here. Its structure can adopt a multi-channel plate type or shell and tube type structure.

[0082] When employing a shell-and-tube structure, the second thermoelectric power generation module may include a shell body 6, and components such as the liquid hydrogen flow channel 1, the first thermally conductive substrate 2, the thermoelectric assembly, the second thermally conductive substrate 4, and the coolant flow channel 5, all housed within the shell body 6. It should be noted that the shell body 6 may be made of insulating material to form an insulating shell, thereby vacuum insulating the entire second thermoelectric power generation module, minimizing heat exchange with the environment, ensuring that the temperature difference primarily affects the thermoelectric material, and improving power generation efficiency.

[0083] In addition, the first thermally conductive substrate 2 (connected to the side of the liquid hydrogen flow channel 1, and is a high thermal conductivity substrate) inside the heat insulation shell is connected to the outer wall of the liquid hydrogen flow channel 1 and one side of the thermoelectric component; the second thermally conductive substrate (connected to the side of the coolant flow channel 5, and is a high thermal conductivity substrate) is connected to the outer wall of the coolant flow channel 5 and the other side of the thermoelectric component.

[0084] like Figure 3 As shown, the left side (not the side pointed to by the arrow) of liquid hydrogen channel 1 is the liquid hydrogen inlet, and the right side (the side pointed to by the arrow) is the gaseous hydrogen outlet. Therefore, liquid hydrogen channel 1 (cold side) can be understood here as the channel through which cryogenic liquid hydrogen enters and flows from its liquid hydrogen inlet, and is in close contact with the cold-end heat-conducting substrate. Here, the cryogenic liquid hydrogen can absorb heat from the opposite coolant channel 5 and the hot end of the thermoelectric chip 3, causing its temperature to rise rapidly and completing the phase change from liquid to gas. When the gaseous hydrogen flows out from the gaseous hydrogen outlet, its temperature has risen to a temperature range suitable for the use of the fuel cell stack (approximately 0-20°C).

[0085] And, such as Figure 3 As shown, the left side (not the side pointed to by the arrow) of coolant channel 5 is the high-temperature coolant inlet, and the right side (the side pointed to by the arrow) is the low-temperature coolant outlet. Therefore, coolant channel 5 (hot side) can be understood here as a channel through which high-temperature coolant (typically >80°C) from the fuel cell stack enters and flows, making close contact with the hot-end thermally conductive substrate. The coolant transfers its heat to the hot end of the thermoelectric chip and acts as a heat source for heating liquid hydrogen, significantly cooling its own temperature (e.g., from 85°C to 35-50°C), before flowing out from the low-temperature coolant outlet, returning to the fuel cell stack or heading to the heat sink.

[0086] Therefore, after the liquid hydrogen channel 1 in the second thermoelectric power generation module receives low-temperature liquid hydrogen and the coolant channel 5 receives high-temperature coolant, the thermoelectric components in the second thermoelectric power generation module can generate electricity by utilizing the temperature difference between the low-temperature liquid hydrogen in the liquid hydrogen channel 1 and the high-temperature coolant in the coolant channel 5 after cooling the battery stack, thus generating the first electrical energy.

[0087] The liquid hydrogen flow channel 1 and the coolant flow channel 5 can flow in the same or different directions. It is preferred that they flow in the same direction. When they flow in the same direction, the temperature difference between the liquid hydrogen flow channel 1 and the coolant flow channel 5 can be kept at its maximum from the inlet until the liquid hydrogen becomes gaseous hydrogen and the high-temperature coolant becomes low-temperature coolant (e.g., from 85°C to 35-50°C).

[0088] It should be noted that the cold side flow channel (liquid hydrogen flow channel 1) and the hot side flow channel (coolant flow channel 5) need to use different sealing materials and structures to withstand ultra-low temperature liquid hydrogen and high temperature coolant, respectively.

[0089] The thermoelectric component transfers heat between the liquid hydrogen channel 1 and the coolant channel 5 to generate electricity based on the temperature difference between the low-temperature liquid hydrogen in the liquid hydrogen channel 1 and the high-temperature coolant in the coolant channel 5, thus producing the first electrical energy.

[0090] The first thermally conductive substrate 2 and / or the second thermally conductive substrate 4 can be made of thermally conductive ceramic, thermally conductive silicone grease or metal material. The materials used to make the first thermally conductive substrate 2 and the second thermally conductive substrate 4 can be the same (both are made of thermally conductive ceramic, thermally conductive silicone grease or metal material) or different (e.g. one is made of thermally conductive ceramic and the other is made of thermally conductive silicone grease, one is made of thermally conductive silicone grease and the other is made of metal material, etc.).

[0091] In simple terms, the first thermally conductive substrate 2 and the second thermally conductive substrate 4 are mainly used to isolate the flow channel from the thermoelectric chip, while ensuring efficient heat conduction.

[0092] In some embodiments of this application, after the current pressure is less than or equal to the second preset pressure threshold, the method further includes: controlling the second thermoelectric power generation module to restore normal power generation.

[0093] Specifically, once the current pressure in the liquid hydrogen storage tank is less than or equal to a second preset pressure threshold, it indicates that the pressure in the liquid hydrogen storage tank has dropped to the preset pressure range, and the tank pressure regulation process can be stopped. At this time, a pressure recovery signal can be generated and sent to the second thermoelectric power generation module or the control unit used to control the second thermoelectric power generation module. After receiving the pressure recovery signal, the second thermoelectric power generation module releases the power adjustment state executed based on the pressure warning signal and restores to normal power generation. The normal power generation can be the power generation determined by the second thermoelectric power generation module based on the liquid hydrogen supply status, the stack coolant temperature, and the operating requirements of the fuel cell system when no pressure warning signal is received. In some embodiments, the second thermoelectric power generation module can directly restore to normal power generation, or it can gradually restore to normal power generation according to a preset recovery rate to reduce the impact of power fluctuations on the liquid hydrogen supply process or the stack coolant heat exchange process.

[0094] Therefore, after the pressure of the liquid hydrogen storage tank returns to below the second preset pressure threshold, the second thermoelectric power generation module can resume normal power generation, and continue to generate electricity by utilizing the temperature difference between the liquid hydrogen and the stack coolant while ensuring the safety of the storage tank pressure.

[0095] In some embodiments of this application, the rate of change of the current pressure inside the liquid hydrogen storage tank is obtained; the rate of reliquefaction of the evaporated liquid hydrogen gas is adjusted by the refrigeration module according to the rate of change and a preset micro-adjustment algorithm. The preset micro-adjustment algorithm can be calibrated according to actual conditions.

[0096] Specifically, after acquiring the current pressure inside the liquid hydrogen storage tank, the rate of change of the current pressure can be determined based on the current pressure acquired at different times. The rate of change of the current pressure characterizes how quickly the pressure inside the liquid hydrogen storage tank rises or falls. After determining the rate of change of the current pressure, an adjustment command for the refrigeration module can be generated based on this rate of change and a preset micro-control algorithm. The refrigeration module adjusts the reliquefaction rate of the evaporated liquid hydrogen gas according to this adjustment command. The preset micro-control algorithm is preferably a PID control algorithm, and its control parameters can be calibrated according to the liquid hydrogen storage tank capacity, the amount of evaporated liquid hydrogen gas produced, the response characteristics of the refrigeration module, and the pressure control accuracy requirements.

[0097] In some embodiments, when the rate of increase of the current pressure is high, the refrigeration module can be controlled to increase the reliquefaction rate of the liquid hydrogen vapor gas. When the rate of increase of the current pressure is low, or when the current pressure gradually approaches a second preset pressure threshold, the refrigeration module can be controlled to decrease the reliquefaction rate of the liquid hydrogen vapor gas to allow the tank pressure to decrease smoothly.

[0098] Therefore, the reliquefaction rate of the liquid hydrogen vapor can be dynamically adjusted according to the pressure change trend of the liquid hydrogen storage tank, avoiding sudden pressure rises and falls and improving the stability of the pressure control of the liquid hydrogen storage tank.

[0099] In some embodiments of this application, in response to the failure to start the first thermoelectric power generation module, a corresponding alarm message is generated and sent to the corresponding target terminal; the cooling module is driven by an external power supply or the electrical energy generated by the second thermoelectric power generation module to reliquefy the liquid hydrogen vaporized gas generated by the liquid hydrogen storage tank to form liquid hydrogen to be recovered.

[0100] Specifically, after the current pressure is greater than or equal to a first preset pressure threshold, a start command is sent to the first thermoelectric power generation module. If no start feedback signal from the first thermoelectric power generation module is received within a preset time after sending the start command, or if the output voltage, output current, or output power of the first thermoelectric power generation module does not meet the preset start conditions, it can be determined that the first thermoelectric power generation module has failed to start. In response to the start failure of the first thermoelectric power generation module, corresponding alarm information is generated and sent to the corresponding target terminal. The alarm information may include the status information of the first thermoelectric power generation module's start failure, the current pressure information of the liquid hydrogen storage tank, or pressure regulation anomaly information. The target terminal may be a vehicle controller, an on-board display terminal, a background monitoring terminal, or other terminals capable of receiving alarm information.

[0101] In the event of a failure to start the first thermoelectric power generation module, to continue the reliquefaction of the evaporated liquid hydrogen gas in the liquid hydrogen storage tank, an external power source can be controlled to supply power to the refrigeration module, or a second thermoelectric power generation module can be controlled to supply power to the refrigeration module. Driven by the electrical energy generated by the external power source or the second thermoelectric power generation module, the refrigeration module reliquefies the evaporated liquid hydrogen gas produced in the liquid hydrogen storage tank to form liquid hydrogen to be recovered. The external power source can be the vehicle power supply system, the station power supply system, or other power sources capable of supplying power to the refrigeration module; the second thermoelectric power generation module is a module that generates electricity using the temperature difference between liquid hydrogen and the fuel cell coolant. Therefore, even if the first thermoelectric power generation module fails to start, the refrigeration module can still be driven to reliquefy the evaporated liquid hydrogen gas through a backup power supply, reducing the risk of a continuous increase in the pressure of the liquid hydrogen storage tank.

[0102] As a specific embodiment of this application, such as Figure 4 As shown, the pressure control method for a liquid hydrogen storage tank may include the following steps: S101, obtain the current pressure inside the liquid hydrogen storage tank.

[0103] S102, determine whether the current pressure is greater than or equal to the first preset pressure threshold.

[0104] Specifically, the current pressure is compared with a first preset pressure threshold. If the current pressure is less than the first preset pressure threshold, the current pressure inside the liquid hydrogen storage tank is continued to be acquired. If the current pressure is greater than or equal to the first preset pressure threshold, step S103 is executed.

[0105] S103, start the first thermoelectric power generation module.

[0106] Specifically, when the current pressure is greater than or equal to the first preset pressure threshold, a start command is sent to the first thermoelectric power generation module, so that the first thermoelectric power generation module generates electricity by utilizing the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment.

[0107] S104, determine whether the first thermoelectric power generation module has started successfully.

[0108] Specifically, the success of the first thermoelectric power generation module's startup can be determined based on its startup feedback signal, or by its output voltage, output current, or output power. If the first thermoelectric power generation module starts successfully, step S105 is executed. If the first thermoelectric power generation module fails to start, step S109 is executed.

[0109] S105, the refrigeration module is driven to operate by the electrical energy generated by the first thermoelectric power generation module.

[0110] Specifically, after the first thermoelectric power generation module is started, it generates electrical energy and supplies the generated electrical energy to the refrigeration module, enabling the refrigeration module to operate under the drive of the electrical energy.

[0111] S106 uses a refrigeration module to reliquefy the evaporated liquid hydrogen gas generated in the liquid hydrogen storage tank to form liquid hydrogen to be recovered.

[0112] Specifically, the liquid hydrogen vaporized gas generated by heat leakage in the liquid hydrogen storage tank enters the refrigeration module, which cools the liquid hydrogen vaporized gas, causing it to revert to a liquid state, thus forming liquid hydrogen to be recovered.

[0113] S107, through the liquid hydrogen recovery module, transfers the liquid hydrogen to be recovered to the liquid hydrogen storage tank.

[0114] Specifically, the liquid hydrogen recovery module returns the liquid hydrogen to be recovered generated by the refrigeration module to the liquid hydrogen storage tank to reduce the gaseous hydrogen content in the liquid hydrogen storage tank and gradually reduce the pressure in the liquid hydrogen storage tank.

[0115] S108, determine whether the current pressure is less than or equal to the second preset pressure threshold.

[0116] Specifically, during the liquid hydrogen recovery process, the current pressure inside the liquid hydrogen storage tank is continuously acquired and compared with a second preset pressure threshold. If the current pressure is still greater than the second preset pressure threshold, the liquid hydrogen vapor gas reliquefaction and the liquid hydrogen to be recovered reflux process continue. If the current pressure is less than or equal to the second preset pressure threshold, step S109 is executed.

[0117] S109, shut down the first thermoelectric power generation module.

[0118] S110, in response to the failure of the first thermoelectric power generation module to start, generates an alarm message and sends it to the corresponding target terminal.

[0119] Specifically, when it is determined that the first thermoelectric power generation module fails to start, an alarm message is generated and sent to the vehicle controller, the vehicle display terminal, the background monitoring terminal or other target terminals to indicate that there is an abnormality in the pressure regulation of the liquid hydrogen storage tank.

[0120] S111 drives the refrigeration module to operate using electrical energy generated by an external power source or a second thermoelectric power generation module.

[0121] Specifically, if the first thermoelectric power generation module fails to start, the external power supply or the second thermoelectric power generation module is controlled to supply power to the refrigeration module, so that the refrigeration module continues to reliquefy the liquid hydrogen vapor generated by the liquid hydrogen storage tank to form liquid hydrogen to be recovered, and the liquid hydrogen to be recovered is transferred to the liquid hydrogen storage tank through the liquid hydrogen recovery module.

[0122] In summary, the pressure control method for a liquid hydrogen storage tank according to the embodiments of this application first obtains the current pressure inside the liquid hydrogen storage tank. Then, in response to the current pressure being greater than or equal to a first preset pressure threshold, a first thermoelectric power generation module is activated to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. Next, the electrical energy generated by the first thermoelectric power generation module drives a refrigeration module to reliquefy the liquid hydrogen vapor produced in the liquid hydrogen storage tank, forming liquid hydrogen to be recovered. Finally, the liquid hydrogen to be recovered is transferred to the liquid hydrogen storage tank through a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down. The first preset pressure threshold is greater than the second preset pressure threshold. Thus, the temperature difference between liquid hydrogen and the environment can be used to achieve thermoelectric self-powered operation, driving the reliquefaction and recovery of BOG (Bottle-Off Gas), reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of the storage tank pressure through dual-threshold start-stop.

[0123] Corresponding to the above embodiments, this application also proposes a pressure control device for a liquid hydrogen storage tank.

[0124] like Figure 5 As shown, the pressure control device 500 for a liquid hydrogen storage tank according to an embodiment of this application includes: a first acquisition module 510, a power generation module 420, a reliquefaction module 530, and a control module 540.

[0125] The system comprises: a first acquisition module 510 for acquiring the current pressure inside the liquid hydrogen storage tank; a power generation module 520 for activating a first thermoelectric power generation module to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment in response to the current pressure being greater than or equal to a first preset pressure threshold; a reliquefaction module 530 for driving a refrigeration module to reliquefy the evaporated liquid hydrogen gas generated in the liquid hydrogen storage tank using the electrical energy generated by the first thermoelectric power generation module, to form liquid hydrogen to be recovered; and a control module 540 for transferring the liquid hydrogen to be recovered to the liquid hydrogen storage tank through the liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down, wherein the first preset pressure threshold is greater than the second preset pressure threshold.

[0126] In some embodiments of this application, the power generation module 520 is further configured to: generate a pressure warning signal for the liquid hydrogen storage tank based on the current pressure in response to the current pressure being greater than or equal to a first preset pressure threshold, and send the pressure warning signal to the second thermoelectric power generation module; adjust the power generation power of the second thermoelectric power generation module according to the pressure warning signal, wherein the second thermoelectric power generation module generates power using the temperature difference between the liquid hydrogen and the fuel cell stack coolant.

[0127] In summary, the pressure control device for a liquid hydrogen storage tank according to the embodiments of this application first acquires the current pressure inside the liquid hydrogen storage tank through a first acquisition module. Then, in response to the current pressure being greater than or equal to a first preset pressure threshold, the power generation module activates a first thermoelectric power generation module to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. Next, the reliquefaction module uses the electrical energy generated by the first thermoelectric power generation module to drive a refrigeration module to reliquefy the liquid hydrogen vapor generated in the liquid hydrogen storage tank, forming liquid hydrogen to be recovered. Finally, the control module transmits the liquid hydrogen to be recovered to the liquid hydrogen storage tank through a liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down, wherein the first preset pressure threshold is greater than the second preset pressure threshold. Thus, the temperature difference between liquid hydrogen and the environment can be used to achieve thermoelectric self-powered operation, driving the reliquefaction and recovery of BOG (Bottle-Off Gas), reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of the storage tank pressure through dual-threshold start-stop.

[0128] Corresponding to the above embodiments, this application also proposes an electronic device.

[0129] like Figure 6 As shown, the electronic device 600 of this application embodiment includes a memory 610, a processor 620, and a computer program stored in the memory 610 and executable on the processor 620. The processor 620 executes the program to implement any of the above-described pressure control methods for liquid hydrogen storage tanks.

[0130] The electronic device according to the embodiments of this application implements any of the above-mentioned pressure control methods for liquid hydrogen storage tanks when the processor executes a computer program. It realizes the thermoelectric self-powered operation by utilizing the temperature difference between liquid hydrogen and the environment to drive the BOG reliquefaction and recovery, reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of storage tank pressure through dual-threshold start-stop.

[0131] Corresponding to the above embodiments, this application also proposes a computer-readable storage medium.

[0132] The computer-readable storage medium of this application embodiment stores a computer program that is executed by a processor to implement any of the above-described pressure control methods for liquid hydrogen storage tanks.

[0133] According to the embodiments of this application, a computer-readable storage medium storing a computer program thereon, when executed by a processor, implements any of the above-mentioned pressure control methods for liquid hydrogen storage tanks. This method utilizes the temperature difference between liquid hydrogen and the environment to achieve thermoelectric self-powered operation, driving BOG reliquefaction and recovery, reducing dependence on external energy supply and hydrogen emissions, and achieving stable closed-loop control of storage tank pressure through dual-threshold start-stop.

[0134] Corresponding to the above embodiments, this application also proposes a computer program product.

[0135] The computer program product of this application includes a computer program that, when executed by a processor, implements any of the above-described pressure control methods for liquid hydrogen storage tanks.

[0136] The computer program product according to the embodiments of this application implements any of the above-mentioned pressure control methods for liquid hydrogen storage tanks when the computer program is executed. It realizes the use of the temperature difference between liquid hydrogen and the environment to achieve thermoelectric self-powered power supply, drive BOG reliquefaction and recovery, reduce external energy supply dependence and hydrogen emissions, and achieve stable closed-loop control of storage tank pressure through dual threshold start-stop.

[0137] Specifically, in the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0138] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0139] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A pressure control method for a liquid hydrogen storage tank, characterized in that, include: Obtain the current pressure inside the liquid hydrogen storage tank; In response to the current pressure being greater than or equal to a first preset pressure threshold, the first thermoelectric power generation module is activated to generate electricity using the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. The electrical energy generated by the first thermoelectric power generation module drives the refrigeration module to reliquefy the liquid hydrogen vapor produced by the liquid hydrogen storage tank, so as to form liquid hydrogen to be recovered. The liquid hydrogen to be recovered is transferred to the liquid hydrogen storage tank via the liquid hydrogen recovery module until the current pressure is less than or equal to a second preset pressure threshold, at which point the first thermoelectric power generation module is shut down; wherein... The first preset pressure threshold is greater than the second preset pressure threshold.

2. The pressure control method for a liquid hydrogen storage tank according to claim 1, characterized in that, The response after the current pressure is greater than or equal to a first preset pressure threshold further includes: A pressure warning signal for the liquid hydrogen storage tank is generated based on the current pressure, and the pressure warning signal is sent to the second thermoelectric power generation module. The second thermoelectric power generation module adjusts its power output according to the pressure warning signal, wherein the second thermoelectric power generation module generates electricity using the temperature difference between the liquid hydrogen and the fuel cell coolant.

3. The pressure control method for a liquid hydrogen storage tank according to claim 2, characterized in that, After the current pressure is less than or equal to the second preset pressure threshold, the following is also included: Control the second thermoelectric power generation module to restore normal power generation.

4. The pressure control method for a liquid hydrogen storage tank according to claim 1, characterized in that, Also includes: Obtain the rate of change of the current pressure inside the liquid hydrogen storage tank; The refrigeration module adjusts the rate of reliquefaction of the liquid hydrogen vaporized gas according to the rate of change and a preset micro-control algorithm.

5. The pressure control method for a liquid hydrogen storage tank according to claim 2, characterized in that, Also includes: In response to the failure to start the first thermoelectric power generation module, a corresponding alarm message is generated and the alarm message is sent to the corresponding target terminal. The refrigeration module is driven by an external power source or the electrical energy generated by the second thermoelectric power generation module to reliquefy the liquid hydrogen vapor produced by the liquid hydrogen storage tank, so as to form liquid hydrogen to be recovered.

6. A pressure control device for a liquid hydrogen storage tank, characterized in that, include: The first acquisition module is used to acquire the current pressure inside the liquid hydrogen storage tank; A power generation module is used to activate a first thermoelectric power generation module in response to the current pressure being greater than or equal to a first preset pressure threshold, so as to generate electricity by utilizing the temperature difference between the liquid hydrogen in the liquid hydrogen storage tank and the current environment. The reliquefaction module is used to drive the refrigeration module with the electrical energy generated by the first thermoelectric power generation module to reliquefy the liquid hydrogen vapor gas generated by the liquid hydrogen storage tank to form liquid hydrogen to be recovered. The control module is used to transfer the liquid hydrogen to be recovered to the liquid hydrogen storage tank through the liquid hydrogen recovery module until the current pressure is less than or equal to the second preset pressure threshold, and then shut down the first thermoelectric power generation module, wherein the first preset pressure threshold is greater than the second preset pressure threshold.

7. The pressure control device for a liquid hydrogen storage tank according to claim 6, characterized in that, The power generation module is also used for: In response to the current pressure being greater than or equal to a first preset pressure threshold, a pressure warning signal for the liquid hydrogen storage tank is generated based on the current pressure, and the pressure warning signal is sent to the second thermoelectric power generation module; The second thermoelectric power generation module adjusts its power output according to the pressure warning signal, wherein the second thermoelectric power generation module generates electricity using the temperature difference between the liquid hydrogen and the fuel cell coolant.

8. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the pressure control method for a liquid hydrogen storage tank as described in any one of claims 1-5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the pressure control method for a liquid hydrogen storage tank as described in any one of claims 1-5.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the pressure control method for liquid hydrogen storage tanks as described in any one of claims 1-5.

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