Liquid hydrogen-based power pack integrated thermal management system

Abstract

Disclosed is a liquid hydrogen-based power pack integrated thermal management system comprising: a fuel cell which is supplied with gaseous hydrogen and oxygen and causes a reaction between the gaseous hydrogen and oxygen to generate electric energy; a hydrogen fuel tank which stores and supplies liquid hydrogen; a heat exchanger which heats and vaporizes the liquid hydrogen supplied from the hydrogen fuel tank via a first hydrogen line and supplies the vaporized hydrogen to the fuel cell via a second hydrogen line, and which supplies cooling water for keeping the fuel cell within a normal operating range temperature by reducing, via a first refrigerant line, the heat load on the fuel cell generated during the operation of the fuel cell, wherein a shell storing the cooling water is connected to the fuel cell via a second refrigerant line, and a spiral heat transfer tube connected at both ends to the first and second hydrogen lines is embedded in the shell; and a control module for overall control of the operation, pressure, and temperature of the system.

Description

Liquid hydrogen-based power pack integrated thermal management system

[0001] The present invention relates to a liquid hydrogen-based power pack integrated thermal management system, and more particularly, to a liquid hydrogen-based power pack integrated thermal management system that vaporizes liquid hydrogen into gaseous hydrogen using waste heat of a fuel cell coolant and supplies it to a fuel cell, and at the same time, removes (cools) residual heat of the coolant using cold heat released when the liquid hydrogen vaporizes, thereby efficiently managing the heat generated by the fuel cell and reducing the overall size (volume) and weight of the power pack system.

[0002] Today, hydrogen fuel cells are gaining attention as a highly energy-efficient and environmentally friendly energy source compared to conventional internal combustion engines because they generate power through the electrochemical reaction of hydrogen and oxygen, and the only product is water.

[0003] In particular, in the automobile industry, due to increasing emission regulations, hydrogen fuel cell vehicles, which operate by using electricity generated by reacting hydrogen and oxygen in the air instead of gasoline internal combustion engines, are attracting attention as next-generation eco-friendly vehicles, and active research is being conducted by various automobile manufacturers.

[0004] These hydrogen fuel cell vehicles, drones, micro-mobility, and other various means of transportation that use hydrogen as fuel and oxygen as an oxidizer use a fuel cell stack as a power source that generates electrical energy by chemically reacting hydrogen fuel in a gaseous or liquid state supplied from a hydrogen tank with oxygen in the air. Therefore, there is no emission of pollutants such as exhaust fumes, so there is no environmental pollution. In addition, they are more energy efficient than other fuels, so they can travel long distances with less fuel.

[0005] Currently, in the automotive industry, efforts are being made to apply hydrogen fuel storage and supply systems to large trucks that emit large amounts of greenhouse gases as hydrogen fuel cell technology advances. Liquid hydrogen-based fuel storage and supply systems, which can overcome the limitations of electric vehicles and increase the efficiency of long-distance, eco-friendly transportation, are emerging as strategically important core technologies.

[0006] Recently, hydrogen fuel cell vehicles have been applying a power pack system that integrates a fuel cell stack, where the chemical reaction between hydrogen and oxygen occurs, a cooling device, a high-voltage battery, and a hydrogen tank.

[0007] Here, the process of releasing high-density liquefied hydrogen from the hydrogen tank and changing its phase is an endothermic reaction, so in order to smoothly supply high-purity hydrogen to the fuel cell stack, an external supply of vaporization heat is required.

[0008] That is, liquid hydrogen is transformed into a gaseous state using an external heat source and then supplied to the fuel cell.

[0009] Typically, to convert liquefied hydrogen stored in a liquid hydrogen fuel storage tank into a state suitable for the fuel inlet conditions of a fuel cell system, processes such as flow rate control, phase change, and pressure control are required. At this time, air-cooling and water-cooling heat exchange processes are required as phase change methods to convert liquefied hydrogen into gaseous hydrogen.

[0010] Air-cooled vaporizers suffer from the disadvantages of moisture in the atmosphere, which can cause freezing in pipes and other areas during heat exchange. Furthermore, the use of air requires a large heat transfer surface area, and controlling air flow increases power consumption. Water-cooled vaporizers require continuous refrigerant circulation, requiring a space-consuming refrigerant circulation system. This, in turn, increases operating and installation costs.

[0011] Meanwhile, in the case of hydrogen fuel cell vehicles, the efficiency of the entire system can be improved by applying an integrated thermal management system that includes heat removal and cooling methods for the fuel cell stack.

[0012] For example, fuel cells continuously remove heat generated above a certain level by circulating coolant that lowers the temperature of the fuel cell using a cooling device to maintain the temperature within the normal operating range during operation.

[0013] In this regard, Patent Document 1 discloses an 'integrated cooling and vaporization system for a hydrogen fuel cell vehicle' that integrates the cooling system of a fuel cell stack and the liquid hydrogen vaporization system.

[0014] [Prior Art Literature]

[0015] [Patent Document]

[0016] (Patent Document 1) KR 10-2522896 B1 2023. 04. 13.

[0017] (Patent Document 2) KR 10-2567867 B1 2023. 08. 11.

[0018] However, since this type of conventional technology uses an indirect heat exchange method through a separate heat management system, its energy efficiency is bound to be relatively lower than that of a direct heat exchange method.

[0019] In addition, there are problems such as the need for separate additional space to install the indirect heat management system, which increases installation costs, slows the response speed to changes in operating load, and increases the number of variables for comprehensively controlling operation, making the control system very complex, which lowers the stability of the system.

[0020] Accordingly, the inventor of the present invention has made great efforts to develop a new structure of a liquid hydrogen-based power pack integrated thermal management system that can efficiently manage the heat generated by the fuel cell and maximize energy efficiency by comprehensively considering the above-mentioned matters and at the same time using the heat load removed or supplied to maintain the fuel cell at the normal operating temperature and the waste heat (residual heat) of the fuel cell coolant as the energy required to vaporize liquid hydrogen, and at the same time using the cold heat released when the liquid hydrogen vaporizes as the energy required to cool the coolant, and can also simplify the configuration of the power pack system to reduce the overall size (volume) and weight of the required system as well as improve the stability of operation and reduce the overall cost, and as a result, has led to the invention of the present invention.

[0021] Therefore, the technical problem and purpose to be solved by the present invention is to provide a liquid hydrogen-based power pack integrated thermal management system that can maximize energy efficiency by utilizing the heat load of fuel cell coolant and the cold heat of liquid hydrogen as energy required for vaporization and cooling.

[0022] The technical problems and objectives to be solved by the present invention are not limited to the technical problems and objectives mentioned above, and other technical problems and objectives not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from the description below.

[0023] In order to effectively achieve a specific technical objective while embodying a new idea for solving the technical problem of the present invention as described above, a specific means according to an embodiment of the present invention is proposed, comprising: a fuel cell that produces electric energy by receiving gaseous hydrogen and oxygen and reacting them; a hydrogen fuel tank that stores and supplies liquid hydrogen; a heat exchanger that heats and vaporizes liquid hydrogen supplied from the hydrogen fuel tank through a first hydrogen line and supplies the heated liquid hydrogen to the fuel cell through a second hydrogen line; and a control module that supplies coolant to the fuel cell through a first refrigerant line to reduce the heat load generated during the operation of the fuel cell and maintain it within a normal operating range temperature, wherein a shell storing the coolant is connected to the fuel cell through a second refrigerant line, and has a built-in spiral heat transfer tube in the shell, both ends of which are connected to the first and second hydrogen lines; and a control module that controls the overall operation, pressure, and temperature of the system.

[0024] Accordingly, the present invention can utilize the high-temperature coolant from the fuel cell as a heating source to circulate the coolant inside the shell through the second coolant line and heat and vaporize the liquid hydrogen passing through the heat transfer tube. In other words, by utilizing the waste heat of the fuel cell coolant as the energy required to vaporize the liquid hydrogen, the heat generated by the fuel cell can be efficiently managed to maximize energy efficiency, and in addition, the configuration of the power pack system can be simplified to not only improve the stability of operation but also reduce the overall size (volume) and weight and reduce overall costs.

[0025] In addition, by utilizing the cold heat of liquid hydrogen, the heat load of the fuel cell is reduced, thereby reducing the power consumption and heat transfer area for cooling the coolant, and preventing condensation and freezing that may occur in the air-cooled heat exchange method for phase-changing liquid hydrogen, and minimizing thermal management control variables, thereby increasing the operational stability of the system.

[0026] In addition, a preferred embodiment (aspect) of the present invention may further include a cooling water pump installed in the middle of the first refrigerant line and circulating the cooling water inside the shell to the fuel cell by pressurizing the cooling water, a first sensor that detects and measures a change in the temperature of the cooling water passing through the first refrigerant line and converts it into a signal and transmits it to the control module, a third refrigerant line connecting between the first refrigerant line and the second refrigerant line, a bypass valve installed in the middle of the third refrigerant line and controls the flow rate of the cooling water circulating into the shell through the second refrigerant line according to a change in the output and reaction heat of the fuel cell, and a second sensor that detects and measures a change in the temperature and pressure inside the hydrogen fuel tank and converts it into a signal and transmits it to the control module.

[0027] In addition, a preferred embodiment (aspect) of the present invention may further include a vent pipe installed in the hydrogen fuel tank, open to the atmosphere to facilitate air exchange and smooth flow of liquid hydrogen, and prevent damage due to pressure generated inside the hydrogen fuel tank, a third hydrogen line connecting the vent pipe and the first hydrogen line, a regulator installed in the middle of the third hydrogen line and adjusting gaseous hydrogen discharged through the vent pipe to be supplied to the heat exchanger through the first hydrogen line when the pressure inside the hydrogen fuel tank is above a certain range, and a first opening / closing valve installed in the middle of the first hydrogen line and controlling the flow rate and flow of liquid hydrogen supplied from the hydrogen fuel tank to the heat exchanger.

[0028] In addition, a preferred embodiment (aspect) of the present invention may further include an injection pipe for injecting liquid hydrogen into the interior of the hydrogen fuel tank, a fourth hydrogen line connecting between the second hydrogen line connecting the fuel cell and the heat transfer tube of the heat exchanger and the injection pipe, and a pressure regulating valve installed in the middle of the fourth hydrogen line and controlling gaseous hydrogen flowing through the fourth hydrogen line to be sent into the interior of the hydrogen fuel tank in order to increase the supply pressure of liquid hydrogen and the internal pressure of the hydrogen fuel tank.

[0029] In addition, a preferred embodiment (aspect) of the present invention may further include a fourth refrigerant line connected to the second refrigerant line and allowing the cooling water flowing in the second refrigerant line to flow in a bypass manner, a radiator installed in the middle of the fourth refrigerant line and dissipating the heat of the cooling water into the atmosphere, and a second opening / closing valve installed in the middle of the fourth refrigerant line and controlling the flow rate and amount of cooling water supplied from the fuel cell to the radiator.

[0030] In addition, a preferred embodiment (aspect) of the present invention further includes a preheater installed on the first hydrogen line and recovering waste heat from a mixture of air and water vapor discharged from the fuel cell and exchanging heat with liquid hydrogen to be introduced into the heat exchanger, thereby further improving thermal efficiency.

[0031] In addition, a preferred embodiment of the present invention further includes a hydrogen supply pump installed in the middle of the first hydrogen line and for supplying liquid hydrogen in the hydrogen fuel tank to the heat exchanger, thereby enabling more efficient operation.

[0032] According to an embodiment that implements the technical idea on which the unique solution is based in order to solve the technical problem of the present invention, liquid hydrogen supplied to the fuel cell is heated and vaporized by using coolant that has reached a high temperature in the fuel cell and supplied to the fuel cell, and at the same time, by removing (cooling) the residual heat of the coolant using the cold heat released when the liquid hydrogen vaporizes, it is possible to change the phase of liquid hydrogen into a gaseous state without an external heat source, and also reduce the heat load of the fuel cell.

[0033] That is, by using the waste heat (residual heat) of the fuel cell coolant as the energy required to vaporize liquid hydrogen and using the cold heat released when the liquid hydrogen vaporizes as the energy required to cool the coolant, the heat generated by the fuel cell can be efficiently managed to maximize energy efficiency.

[0034] In addition, by utilizing the latent and sensible heat of liquid hydrogen, it is possible to directly and quickly respond to the fluctuating heat load generated in the fuel cell stack, thereby reducing the energy consumption and heat transfer area required for system operation compared to existing air-cooled or water-cooled structures, and minimizing thermal management control variables, thereby increasing the operational stability of the system.

[0035] In addition, since there is no need for separate equipment such as indirect thermal management systems, the configuration of the power pack system can be simplified, which not only improves operational stability but also reduces the overall size (volume) and weight, and reduces overall costs.

[0036] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by a person having ordinary skill in the art to which the present invention pertains from the description of the claims.

[0037] FIG. 1 is a schematic diagram of a liquid hydrogen-based power pack integrated thermal management system according to an embodiment of the present invention.

[0038] FIG. 2 is a schematic diagram of a liquid hydrogen-based power pack integrated thermal management system according to another embodiment of the present invention.

[0039] Hereinafter, embodiments according to the present invention will be described in more detail with reference to the attached drawings.

[0040] Prior to this, it should be noted that the terms described below have been defined in consideration of their functions in the present invention, and should be interpreted as concepts that conform to the technical idea of ​​the present invention and meanings commonly used or commonly recognized in the relevant technical field.

[0041] In addition, if it is determined that a detailed description of a known function or configuration related to the present invention may obscure the gist of the present invention, the detailed description is omitted.

[0042] The drawings attached hereto may be exaggerated or simplified in some parts for the purpose of explaining the composition of the technology, the operation and working principles of the technology, convenience of understanding, and clarity of the technology, and it is disclosed that each component in the drawings does not exactly match the actual size and shape.

[0043] In addition, the term and / or in this specification means a combination of a plurality of related described items or including any item among a plurality of related described items, and when it is said that a part includes a certain component, this does not mean that other components are excluded, but rather that other components may be further included, unless specifically stated otherwise.

[0044] That is, the terms “include”, “have”, etc. used in this specification mean that a feature, number, step, process, operation, component, part, or combination thereof exists, but should be understood to not exclude the possibility of the existence or addition of one or more other features, numbers, steps, processes, operations, components, parts, or combinations thereof.

[0045] Furthermore, each process and step may occur in a different order than stated, unless the context clearly dictates otherwise. That is, each process and step may occur in the same order as stated, may be performed substantially simultaneously, or may be performed in the opposite order.

[0046] Meanwhile, the meaning of "part" and "unit" used in the present invention means a module type that performs a unit or role that processes at least one function or certain operation intended for a device or system, and this can be implemented by means such as hardware or software or a combination of hardware and software, or a device or assembly that can perform an independent operation.

[0047] And the meaning of "module" used in the present invention can mean a unit including one or a combination of two or more of hardware, software, or firmware, and can be used interchangeably with terms such as unit, logic, logical block, component, circuit, etc., and can be the minimum unit or part of an integrally configured part, can be the minimum unit or part of a part that performs one or more functions, and can be implemented mechanically or electronically.

[0048] In addition, terms such as top, bottom, upper surface, lower surface, or upper, lower, upper side, lower side, front / back, left / right, etc. used in the present invention are used for convenience to distinguish the relative positions of each component. For example, the upper side in a drawing may be named or referred to as the upper side and the lower side as the lower side, and the length direction may be named or referred to as the front / back direction, and the width direction may be named or referred to as the left / right direction.

[0049] Additionally, the terms first, second, etc. used in the present invention can be used to describe various components. That is, the terms first, second, etc. can be used only for the purpose of distinguishing one component from another.

[0050] <Specific embodiment 1>

[0051] Referring to FIG. 1, the liquid hydrogen-based power pack integrated thermal management system according to an embodiment of the present invention largely includes a fuel cell (10), a hydrogen fuel tank (20), a heat exchanger (30), and a control module (40).

[0052] A fuel cell (10) receives gaseous hydrogen (GH2) and oxygen (Air) and reacts them to produce electrical energy.

[0053] Here, the fuel cell (10) may be any one of an alkaline fuel cell (AFC), a molten carbonate fuel cell (MCFC), a phosphoric acid fuel cell (PAFC), a solid oxide fuel cell (SOFC), a polymer electrolyte fuel cell (PEMFC, PEFC), and a direct methanol fuel cell (DMFC).

[0054] The hydrogen fuel tank (20) stores liquid hydrogen (LH2) in an extremely low temperature state supplied from outside.

[0055] And, a second sensor (54) is installed in the hydrogen fuel tank (20) to detect and measure changes in temperature and pressure inside the tank, convert them into signals, and transmit them to the control module (40).

[0056] In addition, the hydrogen fuel tank (20) is equipped with a ventilation pipe (61) that is open to the atmosphere to facilitate air exchange, ensure smooth flow of liquid hydrogen, and prevent damage caused by pressure generated inside the hydrogen fuel tank (20).

[0057] And, in the middle of the ventilation pipe (61), a safety valve (Pressure Safety Valve) is installed to release gaseous hydrogen (GH2) into the atmosphere when the pressure inside the hydrogen fuel tank (20) reaches a certain set level.

[0058] Here, as a safety valve, for example, a structure can be adopted in which, when it is detected that the gaseous hydrogen pressure in the hydrogen fuel tank (20) is high pressure exceeding the switching operation pressure of 2000 kPa or more, a high pressure switch operates to open the valve and release the gaseous hydrogen into the atmosphere.

[0059] And, an injection pipe (71) for injecting liquid hydrogen into the hydrogen fuel tank (20) is installed therein.

[0060] In addition, a tube is installed in the middle of the injection tube (71) to branch the flow direction of liquid hydrogen, and a check valve (not shown) is installed to automatically limit the flow of liquid hydrogen to prevent backflow.

[0061] Meanwhile, the hydrogen fuel tank (20) can be connected in a single or multiple manner in parallel or series, and the storage pressure range of the liquid hydrogen can be below the critical point.

[0062] For example, the hydrogen fuel tank (20) is configured with a vacuum multilayer insulation system of a double metal container to insulate the liquefied hydrogen, and may be a Type 1 pressure vessel made of stainless steel, high manganese steel, or aluminum steel, a Type 3 pressure vessel made by winding carbon fiber or glass fiber impregnated with resin in the circumferential and longitudinal directions on a thin metal liner, or a Type 4 pressure vessel made by winding carbon fiber or glass fiber impregnated with resin in the circumferential and longitudinal directions on a liner made of a non-metallic material.

[0063] The heat exchanger (30) heats and vaporizes liquid hydrogen supplied from the hydrogen fuel tank (20) through the first hydrogen line (HL1) and supplies it to the fuel cell (10) through the second hydrogen line (HL2).

[0064] And the heat exchanger (30) supplies cooling water (CW) to the fuel cell (10) through the first refrigerant line (CL1) to reduce the heat load generated during operation of the fuel cell (10) and maintain the temperature within the normal operating range.

[0065] Here, the heat exchanger (30) may be configured to have a structure in which a spiral heat transfer tube (32) through which liquid hydrogen flows for heat exchange with cooling water flowing inside a cylindrical container-shaped shell (31) is built into the shell (31).

[0066] And the shell (31) is connected to the fuel cell (10) and the second refrigerant line (CL2), and both ends of the heat transfer tube (32) are connected to the first and second hydrogen lines (HL1) (HL2).

[0067] That is, the second hydrogen line (HL2) connects between the fuel cell (10) and the heat transfer tube (32) of the heat exchanger (30).

[0068] Accordingly, the coolant that has reached a high temperature in the fuel cell (10) can be circulated into the interior of the shell (31) through the second coolant line (CL2) to be used as a heating source to heat and vaporize liquid hydrogen passing through the heat transfer tube (32).

[0069] A cooling water pump (51) is installed in the middle of the first refrigerant line (CL1) to circulate the cooling water inside the shell (31) through the fuel cell (10) to the shell (31).

[0070] Here, the cooling water pump (51) is electrically connected to the control module (40) such that its power source, such as a drive motor, is operated and stopped by a control signal from the control module (40), and can stably perform a pumping action at a predetermined pressure, head, and flow rate to pump the cooling water.

[0071] The cooling water pump (51) is driven by the driving force of a power source such as a drive motor, and the power source can be equipped to be started and stopped by remote control.

[0072] In addition, a first sensor (52) is installed on the first refrigerant line (CL1) to detect and measure the temperature change of the coolant passing through the first refrigerant line (CL1), convert it into a signal, and transmit it to the control module (40).

[0073] The first refrigerant line (CL1) and the second refrigerant line (CL2) are connected by a third refrigerant line (CL3).

[0074] In the middle of the third refrigerant line (CL3), a bypass valve (53) is installed to control the flow rate of coolant circulating into the interior of the shell (31) through the second refrigerant line (CL2) according to the output and reaction heat fluctuations of the fuel cell (10).

[0075] That is, the bypass valve (53) is installed in the middle of the third refrigerant line (CL3) connecting the first refrigerant line (CL1) and the second refrigerant line (CL2) to bypass the coolant according to the output and reaction heat fluctuation of the fuel cell (11).

[0076] Here, the bypass valve (53) may employ a solenoid valve that switches its opening and closing operation by electromagnetic force that converts electric energy into magnetic energy according to the control signal of the control module (40).

[0077] A T-shaped pipe is installed in the middle of the first hydrogen line (HL1) to connect to the third hydrogen line (HL3), and a check valve is installed between the pipe and the hydrogen fuel tank (20) to prevent backflow, and an excess flow valve is installed between the pipe and the first opening / closing valve (65) to automatically close and momentarily block the supply when an overflow occurs in the first hydrogen line (HL1), i.e., when the outflow of liquid hydrogen exceeds a certain level.

[0078] And, in the middle of the first hydrogen line (HL1), a first opening / closing valve (65) is installed to control the flow and amount of liquid hydrogen supplied from the hydrogen fuel tank (20) to the heat exchanger (30).

[0079] Here, the first opening / closing valve (65) may employ a solenoid valve that switches its opening / closing operation by electromagnetic force that converts electric energy into magnetic energy according to a control signal of the control module (40).

[0080] The third hydrogen line (HL3) connects between the vent pipe (61) and the first hydrogen line (HL1).

[0081] And, in the middle of the third hydrogen line (HL3), a regulator (64) is installed to automatically adjust the gaseous hydrogen in the form of evaporated gas discharged through the vent pipe (61) to be supplied to the heat exchanger (30) through the first hydrogen line (HL1) when the pressure inside the hydrogen fuel tank (20) is above a certain range.

[0082] That is, since the third hydrogen line (HL3) between the hydrogen fuel tank (20) and the regulator (64) is always under pressure, when the first pressure is reached, the regulator (64) opens, and when the pressure rises rapidly and reaches the second pressure, which is higher than the first pressure, the safety valve opens.

[0083] Here, the third hydrogen line (HL3) can be directly connected to the hydrogen fuel tank (20) and the first hydrogen line (HL1) without passing through the vent pipe (61).

[0084] And, in the middle of the second hydrogen line (HL2) connecting the fuel cell (10) and the heat transfer tube (32) of the heat exchanger (30), a T-shaped tube is installed to branch the supply and flow direction of gaseous hydrogen (GH2).

[0085] Additionally, the second hydrogen line (HL2) and the injection tube (71) are connected to a fourth hydrogen line (HL4).

[0086] And, in the middle of the fourth hydrogen line (HL4), a pressure control valve (74) is installed to increase the supply pressure of liquid hydrogen (LH2) and the internal pressure of the hydrogen fuel tank (20).

[0087] That is, the pressure regulating valve (74) controls the gaseous hydrogen flowing through the fourth hydrogen line (HL4) to be sent into the interior of the hydrogen fuel tank (20).

[0088] Here, the fourth hydrogen line (HL4) can be directly connected to the hydrogen fuel tank (20) and the second hydrogen line (HL2) without going through the injection pipe (71).

[0089] And on the second refrigerant line (CL2), T-shaped pipes are installed at regular intervals to branch the flow direction of the coolant.

[0090] The fourth refrigerant line (CL4) is connected to the second refrigerant line (CL2) so that the cooling water flowing in the second refrigerant line (CL2) flows in a bypass manner.

[0091] And, a radiator (83) that dissipates the heat of the coolant into the atmosphere is installed in the middle of the fourth refrigerant line (CL4).

[0092] Here, the radiator (83) may be formed in a fin tube manner to increase the heat transfer area for heat exchange, surface area and efficiency, or may include cooling fins or cooling plates.

[0093] Additionally, a second opening / closing valve (84) is installed in the middle of the fourth refrigerant line (CL4) to control the flow and amount of coolant supplied from the fuel cell (10) to the radiator (83).

[0094] Here, the second opening / closing valve (84) may employ a solenoid valve that switches its opening / closing operation by electromagnetic force that converts electric energy into magnetic energy according to a control signal from the control module (40).

[0095] Meanwhile, the heat exchanger (30) vaporizes liquefied hydrogen into vaporized hydrogen when the fuel cell (10) is in rated operation, and its operation can be omitted when in the initial operation state before rated operation.

[0096] Here, the rated operating state means a state in which the fuel cell (10) reaches a preset power generation temperature and generates electric energy.

[0097] Meanwhile, the cooling water (CW) circulated inside the heat exchanger (30) may be composed of at least one of chlorofluorocarbons (CFC), hydrochlorofluorocarbons (HCFC), hydrofluorocarbons (HFC), hydrofluoroolefins (HFO), hydrocarbons, carbon dioxide, ammonia, an aqueous solution of ethylene glycol (EG), and water.

[0098] In addition, the heat exchanger (30) is exemplified and described as a shell and tube type heat exchanger having a structure in which cooling water (CW) flows within a shell (31) and high-pressure liquid hydrogen flows within a heat transfer tube (32) to exchange heat, but it is not limited thereto, and it goes without saying that various types of heat exchangers, such as a plate heat exchanger, can be employed.

[0099] The control module (40) controls the overall operation, pressure and temperature of the system.

[0100] That is, the control module (40) controls the overall operation of various pumps and the opening and closing operation of valves.

[0101] For example, when the pressure inside the hydrogen fuel tank (20) is low, the first opening / closing valve (65) and the pressure regulating valve (74) can be controlled to control the supply and flow of liquid hydrogen sent to the heat exchanger (30) to increase the pressure, and when the pressure is high, the first opening / closing valve (65) can be controlled to block the supply of liquid hydrogen from the hydrogen fuel tank (20) to the heat exchanger (30).

[0102] In addition, by controlling the bypass valve (53) installed in the middle of the third refrigerant line (CL3) according to the output and reaction heat fluctuation of the fuel cell (10) and the amount of liquid hydrogen supplied, the flow rate of the cooling water flowing into the interior of the shell (31) through the second refrigerant line (CL2) can be adjusted, thereby increasing or decreasing the amount of energy supplied necessary for vaporizing the liquid hydrogen.

[0103] Meanwhile, a preheater (90) is installed on the first hydrogen line (HL1) to recover waste heat from a mixture of air and water vapor discharged from a fuel cell (10) and exchange heat with liquid hydrogen to be fed into a heat exchanger (30).

[0104] That is, the preheater (90) is connected to the fuel cell (10) and the air duct (AD).

[0105] <Interaction and Operation Principle>

[0106] The main functions and operating principles of the liquid hydrogen-based power pack integrated thermal management system according to an embodiment of the present invention configured as described above are described as follows.

[0107] First, the cooling water cooled in the heat exchanger (30) is circulated by the pressure of the cooling water pump (51).

[0108] And the heat energy generated during the operation of the fuel cell (10) is recovered through heat exchange with the cooling water circulated by the pressure of the cooling water pump (51), and in this process, the cooling water heated inside the fuel cell (10) retains the residual heat inside the fuel cell (10) and returns to the heat exchanger (30) to be cooled through heat exchange with the liquid hydrogen flowing inside the heat transfer tube (32).

[0109] At this time, liquid hydrogen supplied from the hydrogen fuel tank (20) to the fuel cell (10) is supplied to the fuel cell (10) in a vaporized state through heat exchange with the cooling water while passing through the heat exchanger (30).

[0110] That is, the heat energy generated during the operation of the fuel cell (10) is recovered through heat exchange with the cooling water, and at the same time, the cooling water, in a state in which the heat energy has been absorbed, is transferred to the shell (31) through the second refrigerant line (CL2) by the pressure of the cooling water pump (51), and after heat exchange with the liquid hydrogen in the heat transfer tube (32), the temperature is lowered and continuously circulated back to the fuel cell (10) through the first refrigerant line (CL1).

[0111] And the control module (40) can control the flow rate of coolant circulating into the interior of the shell (31) through the second coolant line (CL2) according to the output (operating mode) and reaction heat fluctuation of the fuel cell (10).

[0112] That is, the control module (40) can control the bypass valve (53) to control the flow rate and amount of cooling water flowing into the fuel cell (10) when temperature control of the fuel cell (10) is required.

[0113] At this time, the control module (40) can increase the cooling efficiency by adjusting the temperature of the coolant heated in the fuel cell (10) to be lowered further as it passes through the fourth coolant line (CL4) to the radiator (83).

[0114] That is, the control module (40) can control the second opening / closing valve (84) to control the flow rate and flow of the cooling water supplied from the fuel cell (10) to the heat exchanger (30) when rapid temperature control of the cooling water is required.

[0115] And the liquid hydrogen coming from the hydrogen fuel tank (20) and entering the heat exchanger (30) can be preheated by exchanging heat with a mixture of air and water vapor discharged from the fuel cell (10) while passing through the preheater (90).

[0116] In addition, when the pressure inside the hydrogen fuel tank (20) is above a certain range, the regulator (64) can automatically adjust so that the gaseous hydrogen discharged through the vent pipe (61) is preferentially supplied to the fuel cell (10) through the heat exchanger (30).

[0117] At this time, the control module (40) can control the first opening / closing valve (65) installed in the middle of the first hydrogen line (HL1) according to load fluctuations to block the flow of liquid hydrogen supplied from the hydrogen fuel tank (20) to the heat exchanger (30).

[0118] Meanwhile, the control module (40) can control the pressure regulating valve (74) installed in the middle of the fourth hydrogen line (HL4) to return some of the gaseous hydrogen coming out of the heat exchanger (30) through the second hydrogen line (HL2) to the inside of the hydrogen fuel tank (20) through the injection pipe (71), and in this way, the pressure inside the hydrogen fuel tank (20) increases, which can be used for pressure feed to send liquid hydrogen to the heat exchanger (30) through the first hydrogen line (HL1).

[0119] <Specific embodiment 2>

[0120] Referring to FIG. 2, a liquid hydrogen-based power pack integrated thermal management system according to another embodiment of the present invention largely includes a fuel cell (10), a hydrogen fuel tank (20), a heat exchanger (30), and a control module (40).

[0121] In particular, a hydrogen supply pump (66) is installed in the middle of the first hydrogen line (HL1) to transfer liquid hydrogen in the hydrogen fuel tank (20) to the heat exchanger (20).

[0122] Accordingly, when the pressure inside the hydrogen fuel tank (20) is above a certain level, the gaseous hydrogen vaporized inside the hydrogen fuel tank (20) is supplied to the fuel cell (10) through the heat exchanger (30) by the operation of the regulator (64), and when the pressure inside the hydrogen fuel tank (20) falls below a certain level, the regulator (64) is closed, and the internal pressure of the hydrogen fuel tank (20) is increased by the operation of the hydrogen supply pump (66) and can be supplied to the heat exchanger (30).

[0123] Among the components related to the integrated thermal management system for a liquid hydrogen-based power pack according to another embodiment of the present invention, components having the same or similar operational effects as the above-described embodiment use the same reference numerals, and repetitive and specific descriptions thereof are omitted.

[0124] Meanwhile, the present invention is not limited to the above-described embodiment and the attached drawings, and can be variously modified and applied in various ways not illustrated within the scope that does not depart from the technical spirit of the present invention, and it is obvious to a person having ordinary skill in the art to which the present invention pertains that it can be widely applied by replacing each component and changing it to an equivalent other embodiment.

[0125] Therefore, the contents related to modifying and applying the technical features of the present invention should be interpreted as being included within the technical idea and scope of the present invention.

Claims

1. A fuel cell (10) that produces electrical energy by reacting gaseous hydrogen and oxygen; Hydrogen fuel tank (20) for storing and supplying liquid hydrogen; A heat exchanger (30) that heats and vaporizes liquid hydrogen supplied from the hydrogen fuel tank (20) through the first hydrogen line (HL1) and supplies the heated liquid hydrogen to the fuel cell (10) through the second hydrogen line (HL2), supplies cooling water to the fuel cell (10) through the first refrigerant line (CL1) to reduce the heat load generated during the operation of the fuel cell (10) and maintain the temperature within the normal operating range, and receives the cooling water that has become high temperature in the fuel cell (10) through the second refrigerant line (CL2); and A control module (40) that controls the overall operation, pressure and temperature of the system; An integrated thermal management system for a liquid hydrogen-based power pack, characterized by including:

2. In paragraph 1, The heat exchanger (30) is characterized in that a shell (31) storing coolant is connected to the fuel cell (10) through a second coolant line (CL2), a spiral heat transfer tube (32) is built into the shell (31) at both ends of which are connected to the first and second hydrogen lines (HL1) (HL2), and the coolant that has reached a high temperature in the fuel cell (10) is circulated into the interior of the shell (31) through the second coolant line (CL2) to use it as a heating source for heating and vaporizing liquid hydrogen passing through the heat transfer tube (32).

3. In paragraph 1, A cooling water pump (51) installed in the middle of the first refrigerant line (CL1) and circulating the cooling water within the shell (31) to the fuel cell (10); A first sensor (52) that detects and measures the temperature change of the cooling water passing through the first refrigerant line (CL1), converts it into a signal, and transmits it to the control module (40); A third refrigerant line (CL3) connecting the first refrigerant line (CL1) and the second refrigerant line (CL2); A bypass valve (53) installed in the middle of the third refrigerant line (CL3) and controlling the flow rate of cooling water circulating into the interior of the shell (31) through the second refrigerant line (CL2) according to the output and reaction heat fluctuation of the fuel cell (10); and A second sensor (54) that detects and measures changes in temperature and pressure within the hydrogen fuel tank (20), converts them into signals, and transmits them to the control module (40); An integrated thermal management system for a liquid hydrogen-based power pack, characterized by further comprising:

4. In paragraph 1 or 2, A ventilation pipe (61) installed in the hydrogen fuel tank (20) and open to the atmosphere to facilitate air exchange, smooth the flow of liquid hydrogen, and prevent damage due to pressure generated inside the hydrogen fuel tank (20); A third hydrogen line (HL3) connecting the above ventilation pipe (61) and the first hydrogen line (HL1); A regulator (64) installed in the middle of the third hydrogen line (HL3) and configured to supply gaseous hydrogen discharged through the vent pipe (61) to the heat exchanger (30) through the first hydrogen line (HL1) when the pressure within the hydrogen fuel tank (20) is above a certain range; and A first opening / closing valve (65) installed in the middle of the first hydrogen line (HL1) and controlling the flow and amount of liquid hydrogen supplied from the hydrogen fuel tank (20) to the heat exchanger (30); An integrated thermal management system for a liquid hydrogen-based power pack, characterized by further comprising:

5. In paragraph 1 or 2, An injection pipe (71) for injecting liquid hydrogen into the interior of the hydrogen fuel tank (20); A fourth hydrogen line (HL4) connecting between the second hydrogen line (HL2) connecting the fuel cell (10) and the heat transfer tube (32) of the heat exchanger (30) and the injection tube (71); and A pressure control valve (74) installed in the middle of the fourth hydrogen line (HL4) and controlling gaseous hydrogen flowing through the fourth hydrogen line (HL4) to be sent into the interior of the hydrogen fuel tank (20) through the injection pipe (71) in order to increase the supply pressure of liquid hydrogen and the internal pressure of the hydrogen fuel tank (20); An integrated thermal management system for a liquid hydrogen-based power pack, characterized by further comprising:

6. In paragraph 1 or 2, A fourth refrigerant line (CL4) connected to the second refrigerant line (CL2) and allowing the cooling water flowing within the second refrigerant line (CL2) to flow in a bypass; A radiator (83) installed in the middle of the fourth refrigerant line (CL4) and dissipating the heat of the cooling water flowing in the fourth refrigerant line (CL4) into the atmosphere; and A second opening / closing valve (84) installed in the middle of the fourth refrigerant line (CL4) and controlling the flow rate and amount of coolant supplied from the fuel cell (10) to the radiator (83); An integrated thermal management system for a liquid hydrogen-based power pack, characterized by further comprising:

7. In paragraph 1 or 2, A preheater (90) installed on the first hydrogen line (HL1) and recovering waste heat from a mixture of air and water vapor discharged from the fuel cell (10) and exchanging heat with liquid hydrogen entering the heat exchanger (30); An integrated thermal management system for a liquid hydrogen-based power pack, characterized by further comprising:

8. In paragraph 1 or 2, A hydrogen supply pump (66) installed in the middle of the first hydrogen line (HL1) and supplying liquid hydrogen in the hydrogen fuel tank (20) to the heat exchanger (20); An integrated thermal management system for a liquid hydrogen-based power pack, characterized by further comprising:

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