Method for handling fuel cell system failure

Abstract

A method for operating a fuel cell system having a fuel cell stack includes detecting a failure of a first cooling fan that blows outside air to a first radiator, opening a first valve to allow a first cooling water that passes through the fuel cell stack to flow to the fuel cell stack, controlling a blower speed, RPM, of an air conditioning system to a maximum level, controlling an opening degree of a second valve according to a cooling degree of the first radiator and a cooling degree of the air conditioning system, and controlling a speed of a first pump to pump the first cooling water to a maximum level.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2021-0089371, filed on July 7, 2021, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to a technique for handling faults in a fuel cell system. Background Technology

[0004] Fuel cell systems generate electricity using fuel cell stacks. For example, when hydrogen is used as fuel in a fuel cell stack, it may be a solution to global environmental problems, hence ongoing research and development of fuel cell systems. A fuel cell system may include: a fuel cell stack that generates electricity; a fuel supply unit that supplies fuel (hydrogen) to the fuel cell stack; an air supply unit that supplies oxygen from the air to the fuel cell stack, the oxygen being an oxidant necessary for the electrochemical reaction; and a thermal management system (TMS) that removes the reaction heat of the fuel cell stack to the outside, controls the operating temperature of the fuel cell stack, and performs water management functions.

[0005] A thermal management system is a cooling device that circulates antifreeze within a fuel cell system. The antifreeze acts as cooling water and maintains the fuel cell stack at an appropriate temperature (e.g., 60°C to 70°C). It may include: a TMS (Transmission Management System) line through which the cooling water circulates; a reservoir for storing the cooling water; a pump that circulates the cooling water; an ion filter that removes ions contained in the cooling water; and a radiator that dissipates heat from the cooling water to the outside. Furthermore, the thermal management system may include: a heater that heats the cooling water; and an air conditioning system (e.g., a heater for heating) that cools and heats the interior of a device containing the fuel cell system (e.g., a vehicle) using the cooling water. The thermal management system can maintain appropriate temperatures for the vehicle's power electronic components and the fuel cell stack. Summary of the Invention

[0006] The present invention aims to solve the above-mentioned problems existing in the prior art, while fully maintaining the advantages achieved by the prior art.

[0007] To effectively manage the heat of a fuel cell system, the temperature of the cooling water passing through the fuel cell stack must be regulated to a desired level. To achieve this, a radiator must dissipate the heat generated in the fuel cell stack into the air. Therefore, the design of the radiator, cooling fan, and pump are considered crucial elements of a fuel cell system. For example, the fuel cell stack can overheat when the cooling fan is disabled.

[0008] While certain vehicles (e.g., construction machinery such as forklifts) may shut down the operation of the fuel cell stack to protect the expensive stack when it overheats due to component failure, such as a cooling fan malfunction, it is also necessary to ensure the fuel cell system is kept cool for a specific period of time, even in the event of component failure, because the fuel cell stack may need to be kept running for emergency measures, such as evacuating vehicles to a safe location.

[0009] The technical problems to be solved by the present invention are not limited to those described above. Any other technical problems not mentioned herein will be clearly understood by those skilled in the art from the following description.

[0010] According to one aspect of this disclosure, a fuel cell system includes: a fuel cell stack; a first cooling line having first cooling water, the first cooling water passing through the fuel cell stack and circulating in the first cooling line; a first radiator disposed on the first cooling line and cooling the first cooling water; an air conditioning system disposed on a first connecting line forming a heating loop with the first cooling line; a first cooling fan blowing outside air to the first radiator; a first valve switching the flow path of the first cooling water to the fuel cell stack or the heater; a second valve switching the flow path of the first cooling water to the fuel cell stack or the first radiator; a first pump disposed on the first cooling line and pumping the first cooling water; and a controller connected to the first cooling fan, the first valve, the second valve, and the first pump, and the controller being configured to: detect a fault in the first cooling fan; open the first valve to allow the first cooling water to flow to the fuel cell stack; control the speed (RPM) of the blower of the air conditioning system to a maximum level; control the opening degree of the second valve according to the cooling degree of the first radiator and the cooling degree of the air conditioning system; and control the speed (RPM) of the first pump to a maximum level.

[0011] According to one aspect of this disclosure, a method for operating a fuel cell system having a fuel cell stack includes: detecting a malfunction of a first cooling fan that blows outside air to a first radiator; opening a first valve to allow first cooling water passing through the fuel cell stack to flow to the fuel cell stack; controlling the speed (RPM) of a blower of an air conditioning system to a maximum level; controlling the opening of a second valve based on the cooling level of the first radiator and the cooling level of the air conditioning system; and controlling the speed (RPM) of a first pump that pumps the first cooling water to a maximum level. Attached Figure Description

[0012] The above and other objects, features and advantages of this disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings:

[0013] Figure 1 Fuel cell systems according to various embodiments are shown;

[0014] Figure 2A and 2B A fuel cell system in which first cooling water flows, according to various embodiments, is shown;

[0015] Figure 3 Fuel cell systems according to various embodiments are shown;

[0016] Figure 4 Fuel cell systems according to various embodiments are shown;

[0017] Figure 5A and 5B A first conduit and a second conduit are shown according to various embodiments;

[0018] Figure 6 These are functional block diagrams of fuel cell systems according to various embodiments;

[0019] Figure 7 The cooling degree is shown based on the opening degree of the second valve;

[0020] Figure 8 The structure of an air conditioning system according to various embodiments is shown;

[0021] Figure 9 This diagram illustrates an operation flowchart according to various embodiments when a cooling fan malfunction is detected; and

[0022] Figure 10 A flowchart illustrating the operation of an output warning alarm according to various embodiments is provided.

[0023] Regarding the description of the accompanying drawings, the same or similar parts may be indicated by the same or similar reference numerals. Detailed Implementation

[0024] In the following description, various embodiments of the present disclosure will be illustrated with reference to the accompanying drawings. Therefore, those skilled in the art will recognize that various modifications, equivalents, and / or substitutions can be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure.

[0025] The various embodiments and terminology used herein do not limit the technical features described herein to specific embodiments and should be construed as including various modifications, equivalents, or substitutions of the embodiments. Regarding the description of the drawings, similar components may be indicated by similar reference numerals. It should be understood that the singular form of a noun corresponding to an item may include one or more things unless the relevant context explicitly indicates otherwise. As used herein, each of such phrases as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B, or C,” “at least one of A, B, and C,” “at least one of A, B, or C” may include all possible combinations of items listed together in one of the corresponding phrases. As used herein, terms such as “first” and “second” or “first” and “second” may be used simply to distinguish one corresponding component from another without otherwise limiting the component (e.g., in terms of importance or order). It should be understood that if an element (e.g., the first element) is referred to as "coupled with" or "connected with" with or without the terms "operably" or "communically", it means that the element can be coupled to another element directly (e.g., via wire), wirelessly, or via a third element.

[0026] The term "module" as used in the various embodiments of this disclosure can include units configured in hardware, software, or firmware, and can be used interchangeably with terms such as logic, logic block, component, or circuit. A module can be an integrated component or a minimum unit or part that performs one or more functions. For example, according to one embodiment, the module can be implemented as an application-specific integrated circuit (ASIC).

[0027] Various embodiments of this disclosure can be implemented by software (e.g., a program) including one or more instructions stored in a machine-readable storage medium (e.g., internal or external memory). For example, a device can invoke at least one of the one or more instructions stored in the storage medium and can execute that instruction. This allows at least one function to be performed according to the invoked at least one instruction. The one or more instructions may include code generated by a compiler or code executable by an interpreter. The device-readable storage medium may be provided in the form of a non-transitory storage medium. Here, "non-transitory storage medium" means that the storage medium is a tangible device and does not include signals (e.g., electromagnetic waves). In terms of terminology, there is no difference between the case where data is semi-permanently stored in the storage medium and the case where data is temporarily stored in the storage medium.

[0028] According to one embodiment, methods according to various embodiments of this disclosure can be provided as being included in a computer program product. The computer program product can be traded between a seller and a buyer. The computer program product can be distributed in the form of a device-readable storage medium (e.g., a compact disk read-only memory, CD-ROM) or distributed via an application store (e.g., downloaded or uploaded) or directly or online between two user devices. In online distribution, at least a portion of the computer program product can be at least temporarily stored in a storage medium, such as the memory of a manufacturer's server, an application store's server, or a relay server, which can be read by a device or temporarily generated.

[0029] According to various embodiments, the elements (e.g., modules or programs) of the above-described elements may include one or more entities, and some of these entities may be arranged to be separate from other elements. According to various embodiments, one or more elements or operations may be omitted from the above-described elements, or one or more other elements or operations may be added. Alternatively or additionally, multiple elements (e.g., modules or programs) may be integrated into one element. In this case, the integrated element may perform one or more functions of the elements of the multiple elements in the same or similar manner as the corresponding elements of the multiple elements performed before integration. According to various embodiments, operations performed by modules, programs, or other elements may be performed sequentially, in parallel, repeatedly, or heuristically; one or more operations may be performed in a different order or omitted, or one or more other operations may be added.

[0030] Figure 1 and Figure 4 Fuel cell systems according to various embodiments are shown.

[0031] Reference Figure 1A fuel cell system for a vehicle may include a first cooling line 110 in which first cooling water passing through the vehicle's fuel cell stack 10 circulates, and a second cooling line in which second cooling water passing through the vehicle's power electronic components circulates. In an embodiment, the fuel cell system may also include a heat exchanger 300 for heat exchange between the first and second cooling water, but the heat exchanger 300 may be omitted.

[0032] The fuel cell system may include a first connecting line 130, a second connecting line 150, and a third connecting line 140 to form a heating loop (heating circulation path) with the first cooling line 110 or to form a cooling line with the first cooling line 110. First cooling water may be cooled or heated while circulating in the first connecting line 130, the second connecting line 150, or the third connecting line 140. As an example, such as... Figure 2A As shown, the first cooling line 110 can form a heating circuit with the first connecting line 130 and the third connecting line 140 to ensure the cold start capability under initial vehicle start-up conditions, and as... Figure 2B As shown, a cooling loop can be formed, in which first cooling water passes through a first radiator 60, allowing the heat generated by the fuel cell stack 10 to dissipate to the outside during vehicle operation. In another embodiment, when the outside air temperature reaches a certain temperature, the first cooling line 110 does not form a heating loop, and the fuel cell system can utilize the heat from the fuel cell stack 10 to ensure its start-up capability. The fuel cell stack 10, first valve 20, first pump 30, second valve 40, and first radiator 60 can be mounted on the first cooling line 110, in which the first cooling water circulates.

[0033] The fuel cell stack 10 (or may be referred to as a "fuel cell") may have a structure in which electricity is generated through an oxidation / reduction reaction of fuel (e.g., hydrogen) and an oxidant (e.g., air). As an example, the fuel cell stack 10 may include: a membrane electrode assembly (MEA) in which a catalyst electrode layer for electrochemical reactions is attached to the opposite side of an electrolyte membrane through which hydrogen ions pass; a gas diffusion layer (GDL) that uniformly distributes the reactant gases and transfers the generated electrical energy; gaskets and coupling mechanisms for maintaining the seal and appropriate coupling pressure of the reactant gases and a first cooling water; and bipolar plates that cause the flow of reactant gases and the first cooling water.

[0034] In fuel cell stack 10, hydrogen as fuel and air (oxygen) as oxidant are supplied to the anode and cathode of the membrane electrode assembly, with hydrogen supplied to the anode and air supplied to the cathode. The hydrogen supplied to the anode is decomposed into protons and electrons by a catalyst in an electrode layer disposed on opposite sides of the electrolyte membrane. Only hydrogen ions can selectively pass through the electrolyte membrane, which serves as a cation exchange membrane, to the cathode, while electrons can pass through a gas diffusion layer and bipolar plates to the cathode. At the cathode, the hydrogen ions supplied through the electrolyte membrane and the electrons transferred through the bipolar plates encounter oxygen in the air supplied to the cathode by the air supply device, resulting in a reaction that produces water. Then, due to the flow of hydrogen ions, electrons can flow through external wires, generating an electric current.

[0035] The first valve 20 can switch the flow path of the first cooling water to the first connecting line 130, which is equipped with a heater, or to the fuel cell stack 10 on the first cooling line 110. For example, the first valve 20 can be connected to one end of the first pump 30, one end of the first connecting line 130, and one end of the fuel cell stack 10 on the first cooling line 20. The first valve 20 can include various valve devices that can selectively switch the flow path of the first cooling water. For example, the first valve 20 can be a three-way valve. In this case, the first valve 20 can include a first port 21 connected to the first cooling line 110 to allow the first cooling water pumped by the first pump 30 to be introduced through it, a second port 22 connected to the first cooling line 110 to allow the first cooling water through the first valve 20 to be introduced into the fuel cell stack 10, and a third port 23 connected to one end of the first connecting line 130. When the second port 22 and the third port 23 of the first valve 20 are opened and closed, the flow path of the first cooling water can be switched to the heater 50 of the first connecting line 130 or the fuel cell stack 10. That is, when the second port 22 is open and the third port 23 is closed, the first cooling water can be introduced into the fuel cell stack 10; conversely, when the third port 23 is open and the second port 22 is closed, the first cooling water can be introduced into the heater 50 through the first connecting line 130.

[0036] The first connecting line 130 can form a heating loop (heating circulation path) with the first cooling line 110 to heat the first cooling water. For example, the first cooling water flowing along the first connecting line 130 can be heated by passing through the heater 50 installed in the first connecting line 130. One end of the first connecting line 130 can be connected to the first cooling line 110 at a first point located between the outlet of the first pump 30 and the fuel cell stack 10, and the other end of the first connecting line 130 can be connected to the first cooling line 110 at a second point located between the inlet of the first pump 30 and the fuel cell stack 10. Here, the inlet of the first pump 30 can be defined as the inlet through which the first cooling water is introduced into the first pump 30. Furthermore, the outlet of the first pump 30 can be defined as the outlet through which the first cooling water is discharged from the first pump 30. Furthermore, the portion between the outlet of the first pump 30 and the fuel cell stack 10 can be defined as the portion where the first cooling water discharged from the first pump 30 flows to the first cooling water inlet (not shown) of the fuel cell stack 10. Furthermore, the portion between the inlet of the first pump 30 and the fuel cell stack 10 can be defined as the portion in which the first cooling water discharged from the cooling water outlet (not shown) of the fuel cell stack 10 flows to the inlet of the first pump 30.

[0037] The first pump 30 may be configured to force the first cooling water to flow. The first pump 30 may include various devices capable of pumping the first cooling water, and this disclosure does not limit the type or number of the first pump 30.

[0038] The second valve 40 can switch the flow path of the first cooling water to the first radiator 60 or the fuel cell stack 10 on the first cooling line 110. For example, the second valve 40 can be located on the first cooling line 110 between the first pump 30 and the first radiator 60, and can be connected to one end of the third connecting line 140 and the outlet of the first radiator 60. The second valve 40 can include various valve devices that can selectively switch the flow path of the first cooling water to the first radiator 60 or the fuel cell stack 10. As an example, the second valve 40 can be a four-way valve or a three-way valve. When the second valve 40 is a three-way valve, it can include a first port 41 connected to the third connecting line 140; a second port 42 connected to the first cooling line 110, through which the first cooling water from the first radiator 60 is introduced; and a third port 44 connected to the first cooling line 110, through which the first cooling water is introduced to the first pump 30. And when the second valve 40 is a four-way valve, it can further include a third port 43 connected to one end of the second connecting line 150. As the first port 41 or the second port 42 of the second valve 40 opens and closes, the flow path of the first cooling water can be switched to the first radiator 60 or the fuel cell stack 10. That is, when the first port 41 is open and the second port 42 is closed, the first cooling water is introduced into the fuel cell stack 10 without passing through the first radiator 60, and conversely, when the second port 42 is open and the first port 41 is closed, the first cooling water can be introduced into the fuel cell stack 10 after passing through the first radiator 60.

[0039] The second connecting line 150 can form a heating loop with the first cooling line 110 to heat the air conditioning system (HVAC system) 90. As an example, the second connecting line 150 can form a loop for a heater (not shown) to heat the air conditioning system 90. One end of the second connecting line 150 can be connected to the first cooling line 110 between a first point (where one end of the first connecting line 130 is connected to the first cooling line 110) and the inlet of the fuel cell stack 10, and a portion of the first cooling water can circulate through the second connecting line 150. The other end of the second connecting line 150 can be connected to the first cooling line 110 between the first pump 30 and a second point (where the other end of the first connecting line 130 is connected to the first cooling line 110).

[0040] An ion filter 95, which filters ions from the first cooling water that has passed through the air conditioning system 90, can be installed in the second connecting line 150. Because current flowing through the first cooling water could short-circuit the fuel cell stack 10 or cause current to flow into the first cooling water when its conductivity increases due to system corrosion or leakage, the first cooling water must maintain a low conductivity. The ion filter 95 can be configured to remove ions contained in the first cooling water to maintain its conductivity at a specific level or lower. Thus, during cold start, when the supply of the first cooling water to the fuel cell stack 10 is interrupted (the second port 22 of the first valve 20 is closed), the first cooling water circulates (temperature rise loop) through the heater 50 of the first connecting line 130 and also circulates along the second connecting line 150, thereby allowing filtration (removal of ions contained in the first cooling water) by the ion filter 95 installed in the second connecting line 150 during cold start. Therefore, the conductivity of the first cooling water introduced into the fuel cell stack 10 immediately after cold start can advantageously be maintained at a specific level or lower.

[0041] The third connecting line 140 can form a cooling loop with the first cooling line 110 to cool the first cooling water. For example, one end of the third connecting line 140 can be connected to the first cooling line 110 between the first pump 30 and the first radiator 60, and the other end of the third connecting line 140 can be connected to the first cooling line 110 between the cooling water outlet of the fuel cell stack 10 and the first radiator 60.

[0042] The first radiator 60 can be configured to cool first cooling water. The first radiator 60 can have various structures for cooling the first cooling water, and this disclosure does not limit or restrict the type and structure of the first radiator 60. The first radiator 60 can be connected to a first reservoir 62, in which the first cooling water is stored.

[0043] The fuel cell system may include a first temperature sensor 112 for measuring the temperature of the first cooling water between the fuel cell stack 10 and the first point (first valve 20), a second temperature sensor 114 for measuring the temperature of the first cooling water between the other end of the first connecting line 130 and the first pump 30, and a third temperature sensor 116 for measuring the temperature of the cooling water in the heater 50. The fuel cell system may control the flow rate of the first cooling water introduced into the fuel cell stack 10 based on the temperatures measured by the first temperature sensor 112, the second temperature sensor 114, and the third temperature sensor 116. For example, when the measured temperature of the first cooling water circulating along the first cooling line 110 is lower than a preset target temperature, the flow rate of the introduced first cooling water may be controlled to be lower than a preset flow rate. Thus, since the flow rate of the first cooling water introduced into the fuel cell stack 10 is controlled to be lower when the measured temperature of the first cooling water is lower, the thermal effects or performance degradation caused by the deviation between the temperature of the first cooling water remaining inside the fuel cell stack 10 and the temperature of the first cooling water introduced into the fuel cell stack 10 can be advantageously minimized.

[0044] The second cooling line 120 passes through the power electronic component 200, and the second cooling water can circulate along the second cooling line 120. Here, the vehicle's power electronic component 200 can be understood as a component that uses the vehicle's power supply as its energy source, and the type and number of power electronic components 200 are not limited or restricted in this disclosure. As an example, the power electronic component 200 may include: a bidirectional high voltage DC-DC converter (BHDC) 210 disposed between the fuel cell stack 10 and the vehicle's high-voltage battery (not shown); a blower pump controller unit (BPCU) 220 that controls a blower (not shown) supplied to drive the external air to the fuel cell stack 10; a low-voltage DC-DC converter 230 that converts the DC high voltage received from the high-voltage battery into DC low voltage; an air compressor (ACP) 240 that compresses the air supplied to the fuel cell stack 10; and at least any one of the following: an air cooler 250. Although Figure 1 and Figure 4 Not shown, but power electronic component 200 may also include a DC-DC buck / boost converter.

[0045] A second pump 205 for forcing the flow of the second cooling water can be installed on the second cooling line 120. The second pump 205 may include a pumping device capable of pumping the second cooling water, and the type and characteristics of the second pump 205 are neither limited nor restricted.

[0046] A second radiator 70 for cooling the second cooling water can be installed on the second cooling pipeline 120. The second radiator 70 can have various structures capable of cooling the second cooling water, and the type and structure of the second radiator 70 are neither limited nor restricted. The second radiator 70 can be connected to a second water storage tank 72, in which the first cooling water is stored.

[0047] In this embodiment, the first heat sink 60 and the second heat sink 70, as... Figure 1 As shown, both radiators can be cooled simultaneously by a single cooling fan 80. As an example, the first radiator 60 and the second radiator 70 can be arranged in parallel, and the cooling fan 80 can be configured to direct outside airflow to the first radiator 60 and the second radiator 70. Because the first radiator 60 and the second radiator 70 are cooled simultaneously by a single cooling fan 80, the structure of the fuel cell system can be simplified, design freedom and space utilization can be improved, and the power consumption for cooling the first radiator 60 and the second radiator 70 can be minimized.

[0048] In one embodiment, such as Figure 3 As shown, the first cooling fan 80 for cooling the first radiator 60 and the second cooling fan 85 for cooling the second radiator 70 can be configured separately. In this case, when controlling the RPM of the first cooling fan 80, the fuel cell system can exclude parameters related to the thermal load of the power electronic components 200. The embodiments described below are based on... Figure 1 The structure of the fuel cell system is similar, but the same principle can be applied to... Figure 3 The structure of the fuel cell system.

[0049] Refer again Figure 1The heat exchanger 300 can be configured to exchange heat between a first cooling water and a second cooling water. When the heat exchanger 300 is included, the first cooling line 110 and the second cooling line 120 can constitute a thermal management system (TMS) pipeline, wherein the first cooling water and the second cooling water can flow while exchanging heat, and in this case, the first cooling water or the second cooling water can be used as a cooling medium or a heat transfer medium in the TMS pipeline. For example, since the temperature of the second cooling water cooling the power electronic components is lower than the temperature of the first cooling water cooling the fuel cell stack 10, advantageously, the fuel cell system can reduce the temperature of the first cooling water through heat exchange between the first cooling water and the second cooling water without increasing the capacity of the first radiator 60 and the cooling fan 80, thereby improving the cooling efficiency of the fuel cell stack 10 and enhancing safety and reliability. Furthermore, because the fuel cell system can reduce the temperature of the first cooling water while stopping vehicles that cannot use drive air (e.g., construction machinery), it is advantageous to ensure high-output drive of the fuel cell stack 10 and enhance safety and durability.

[0050] In this embodiment, heat exchanger 300 can be connected to a first cooling line 110 between the outlet of the first radiator 60 and the fuel cell stack 10, and a second cooling line 120 can be connected to the outlet of the second radiator 70 and the power electronic components, such that first cooling water passes through heat exchanger 300. For example, the first cooling water can flow along heat exchanger 300 connected to the first cooling line 110, and the second cooling line 120 can pass through the interior of heat exchanger 300 to be exposed to the first cooling water (e.g., the first cooling water flows along the circumference of the second cooling line 120). In this way, the fuel cell system can reduce the temperature of the first cooling water introduced into the fuel cell stack 10 through heat exchange between the first and second cooling water. The first temperature of the first cooling water passing through the first radiator 60 can be higher than the second temperature of the second cooling water passing through the second radiator 70, and the third temperature of the first cooling water passing through heat exchanger 300 can be lower than the first temperature. For example, the first temperature of the first cooling water can be about 10°C higher than the second temperature of the second cooling water, and the third temperature of the first cooling water (after heat exchange with the second cooling water) passing through the heat exchanger 300 can be 1°C lower than the first temperature.

[0051] according to Figures 1 to 3 In one embodiment, the heat exchanger 300 is separately disposed from the first radiator 60, but in another embodiment, such as Figure 4 As shown, the heat exchanger 300 can be directly connected to the first radiator 60. For example, the heat exchanger 300 can be connected to a specific location (upper left end) of the first radiator 60, but this disclosure is not limited thereto. When the heat exchanger 300 is connected to the upper left end of the first radiator 60, the first radiator 60 and the heat exchanger 300 can be connected as follows: Figure 5A and Figure 5B Implementation as shown.

[0052] Figure 5A and 5B A first pipe and a second pipe according to various embodiments are shown.

[0053] Reference Figure 5A and 5B The first radiator 60 may include a first conduit 64 forming a first channel 64a, through which first cooling water flows. The heat exchanger 300 may include a second conduit 302 configured to exchange heat with the first cooling water inside the first channel 64a, and the second cooling water may exchange heat with the first cooling water in the first channel 64a while flowing along the second conduit 302. The second conduit 302 may form a second channel 302a, through which second cooling water flows, and at least a portion of the second conduit 302 may be exposed to the first cooling water inside the first channel 64a. The shape and structure of the second conduit 302 may be varied according to required conditions and design specifications, and this disclosure is not limited or restricted by the shape and structure of the second conduit 302. According to an embodiment, heat dissipation fins may be formed on the outer surface of the second conduit to increase the contact area of ​​the outer surface of the second conduit exposed to the first cooling water, thereby increasing the cooling effect of the first cooling water. According to this embodiment, a seal 304 (e.g., rubber or silicone material) may be provided between the first conduit 64 and the second conduit 302. In this way, by providing a seal 304 between the first conduit 64 and the second conduit 302, the installed state of the first channel 64a can be maintained stably.

[0054] Figure 6 These are functional block diagrams of fuel cell systems according to various embodiments. Figure 7 The cooling degree is shown based on the opening degree of the second valve. Figure 8 The structure (e.g., side sectional view) of an air conditioning system according to various embodiments is shown. Figure 6 The configuration shown can be a hardware device or a program (or application) that includes instructions.

[0055] The controller 610 may be a hardware device, such as a processor or central processing unit (CPU), or a program implemented by the processor. The controller 610 may be connected to the configuration of the fuel cell system to perform the overall functions of the fuel cell system. As an example, the controller 610 may detect a malfunction of the cooling fan 80. For example, the controller 610 may detect a disabled state of Controller Area Network (CAN) communication between the controller 610 and the cooling fan 80, may detect that the temperature of the first cooling water has not changed within a specific time period, or may detect that the power consumption of the cooling fan 80 has not changed within a specific time period. The temperature of the first cooling water may be the temperature of the first cooling water at the inlet of the fuel cell stack 10, which is measured by the first temperature sensor 112. Because forced convection cooling is not possible in the first radiator 60 (or the second radiator 70) when the operation of the cooling fan 80 is disabled, the temperature of the first cooling water heated in the fuel cell stack 10 may not decrease to a specific temperature. The controller 610 may control the configuration of the fuel cell system to minimize overheating of the fuel cell system when the cooling fan 80 is disabled. Therefore, controller 610 may include a first valve controller 612, a second valve controller 614, a first pump controller 616, a second pump controller 618, and an air conditioning controller 620. The configuration included in the controller may be implemented by individual devices (or programs) or by an integrated module.

[0056] The first valve controller 612 and the second valve controller 614 can respectively control the opening degree of the first valve 20 and the second valve 40. In this embodiment, when a failure of the cooling fan 80 is detected, the first valve controller 612 can control the first valve 20 so that the first cooling water does not flow to the first connecting line 130 but flows to the fuel cell stack 10 and the heater core 94 of the air conditioning system 90 to ensure the cooling degree of the fuel cell system. Furthermore, the second valve controller 614 can control the second valve 40 so that the first cooling water that has passed through the fuel cell stack 10 does not flow to the third connecting line 140 but flows to the first radiator 60 and the heater core 94 of the air conditioning system 90. The first cooling water can be cooled by natural convection when passing through the first radiator 60 and by the blower 92 when passing through the heater core 94. In this case, according to the cooling degree of the air conditioning system 90 and the cooling degree of the first radiator 80, the second valve controller 614 can control the opening degree of the second valve 40 to a specific value. For example, refer to... Figure 7The horizontal axis of the figure represents the opening angle (or "operating angle") of the second valve 40 (in degrees), and its vertical axis represents the flow rate (LPM) and cooling capacity (kW). When the opening angle of the second valve 40 exceeds a certain angle (e.g., 80 degrees), the cooling capacity caused by the radiator (radiator cooling capacity) can increase, while the flow rate of the first cooling water increases on the side closer to the radiator (e.g., first radiator 60). As the opening angle increases, the cooling capacity caused by the air conditioning system (air conditioning system cooling capacity) can decrease as the flow rate of the first cooling water decreases on the side closer to the air conditioning system (e.g., air conditioning system 90). The second valve controller 614 can control the second valve 40 based on the maximum opening angle (e.g., K) of the sum of the radiator cooling capacity and the air conditioning system cooling capacity.

[0057] The first pump controller 612 and the second pump controller 616 can respectively control the operation of the first pump 30 and the second pump 205. For example, when a malfunction of the cooling fan 80 is detected, the first pump controller 614 can control the speed RPM of the first pump 30 to the maximum level to ensure that the flow rate of the first cooling water is at the maximum level. When the first cooling water can exchange heat with the second cooling water through the heat exchanger 300, the second pump controller 616 can control the speed RPM of the second pump 205 to the maximum level to increase the degree of heat exchange.

[0058] When a malfunction of the cooling fan 80 is detected, the air conditioning system controller 620 can control at least one of the configurations 91 to 94 included in the air conditioning system 90 to maximize the heat dissipated from the heater core 94. For example, refer to Figure 8 The air conditioning system 90 may include a heater core 94 that performs a heating function, an evaporator 91 that cools air when the air conditioning is turned on, a blower 92 that guides the cooling air to the heater core 94, and temperature gates 93-1 and 93-2 that block the flow of air to the heater core 94 by opening and closing. The air conditioning system controller 620 may set the speed (RPM) of the blower 92 to its maximum level, causing the cold air generated by the evaporator 91 to flow in a specific direction 805 and through the heater core 94, and may control the opening and closing of the temperature gates 93-1 and 93-2 to direct the air that has passed through the evaporator 91 to the heater core 94. For example, in the open state, the first temperature gate 93-1 may move downwards, while the second temperature gate 93-2 may move upwards.

[0059] Figure 9 A flowchart illustrating operation when a cooling fan failure is detected, according to various embodiments, is shown. The operation of the flowchart described below can be implemented by the fuel cell system, or by a configuration included in the fuel cell system (e.g., controller 610).

[0060] Reference Figure 9 During operation 910, the fuel cell system can detect malfunctions in the cooling fan 80.

[0061] In operation 920, the fuel cell system can open the first valve 20, allowing the first cooling water to flow to the fuel cell stack 10.

[0062] In operation 930, the fuel cell stack can control (set) the RPM of the blower 92 of the air conditioning system 90 to its maximum value. Furthermore, in operation 930, the fuel cell system can open temperature gates 93-1 and 93-2, allowing cooling air to pass through the heater core 94. Additionally, in operation 934, the fuel cell system can turn the air conditioning on and off based on whether a condenser is included. For example, when a condenser is not included in the vehicle cooling module, which includes a first radiator 60, a second radiator 70, and a cooling fan 80, the fuel cell system can control the air conditioning to be turned on to cool the air. Conversely, when a condenser is included in the vehicle cooling module, the fuel cell system can control the air conditioning to be turned on and off because when the air conditioning is running, the temperature of the first radiator 60 may increase due to the increased temperature of the condenser.

[0063] In operation 940, based on the cooling levels of the first radiator 60 and the air conditioning system 90, the fuel cell system can control the opening of the second valve 40. The fuel cell system can control the opening of the second valve 40 to maximize the sum of the cooling levels of the first radiator 60 and the air conditioning system 90.

[0064] In operation 950, the fuel cell stack can control the rotational speed (RPM) of the first pump 30 to its maximum value. When the fuel cell system includes a second radiator 70 and a first radiator 60, or when the fuel cell system includes a heat exchanger 300, in operation 955, the fuel cell system can control the rotational speed (RPM) of the second pump 205 to its maximum level.

[0065] Figure 10 A flowchart illustrating the operation of the output alarm according to various embodiments is shown. Figure 10 The operation shown can be performed in Figure 9 The operation can be executed at any point in time after operation 910. For example, the fuel cell system can execute the operation after operation 950, or after operations 910, 920, 930, 932, 934, or 940. Figure 10 The operation shown.

[0066] Reference Figure 10 In operation 1010, the fuel cell system can monitor the temperature of the first cooling water at the inlet of the fuel cell stack 10. For example, the controller 610 can monitor the temperature of the cooling water via the first temperature sensor 112.

[0067] In operation 1020, the fuel cell system can identify whether the monitored temperature of the cooling water exceeds a threshold. Unless the cooling water temperature exceeds the threshold temperature, the fuel cell system can repeat operations 1010 to 1020.

[0068] When the temperature of the cooling water exceeds the threshold temperature, the fuel cell system can output an alarm in operation 1030 to ensure the safety of the vehicle and the driver.

[0069] According to embodiments of this disclosure, a fuel cell system can protect the fuel cell stack, which is an expensive device, from damage due to overheating, even when a failure is detected in components used for thermal management (e.g., cooling fans).

[0070] According to embodiments of this disclosure, even in emergency situations, while passengers and vehicles are moved to a safe location, the fuel cell system can ensure system output, wherein components used for thermal management, such as cooling fans, are detected.

[0071] Furthermore, this disclosure can provide various effects that can be identified directly or indirectly.

Claims

1. A fuel cell system, comprising: Fuel cell stack; A first cooling line has a first cooling water supply, which passes through the fuel cell stack and circulates within the first cooling line. A first radiator is disposed on the first cooling pipeline and configured to cool the first cooling water; An air conditioning system is installed on a first connecting pipeline that forms a heating circuit with the first cooling pipeline; A first cooling fan is configured to blow outside air onto the first radiator; A first valve is configured to switch the flow path of the first cooling water to the fuel cell stack or heater. A second valve is configured to switch the flow path of the first cooling water to the fuel cell stack or the first radiator. A first pump is disposed on the first cooling line and configured to pump the first cooling water. and The controller is connected to the first cooling fan, the first valve, the second valve, and the first pump. The controller is configured as follows: Detect a fault in the first cooling fan; When a malfunction of the first cooling fan is detected, the first valve is opened to allow the first cooling water to flow to the fuel cell stack; The blower speed (RPM) of the air conditioning system is controlled to the maximum level. The opening degree of the second valve is controlled based on the cooling degree of the first radiator and the cooling degree of the air conditioning system; and Control the speed (RPM) of the first pump to the maximum level.

2. The fuel cell system as described in claim 1, wherein, The controller The first cooling fan is detected by detecting the disabled state of Controller Area Network (CAN) communication, by detecting that the temperature of the first cooling water does not change within a specific time period, or by detecting that the power consumption of the first cooling fan does not change within a specific time period.

3. The fuel cell system as described in claim 1, wherein, The controller is also configured to: The temperature control gate is in the open state, allowing cooling air in the air conditioning system to flow towards the heater core.

4. The fuel cell system as described in claim 3, wherein, The controller is configured to: Turn on the air conditioner configured to cool the air flowing to the heater core.

5. The fuel cell system of claim 3, further comprising: Condenser; The controller is configured as follows: The air conditioner, configured to cool the air flowing to the heater core, is turned off.

6. The fuel cell system of claim 1, further comprising: A second cooling line with a second cooling water, the second cooling water passing through power electronic components and circulating in the second cooling line; The second radiator is disposed on the second cooling line and configured to cool the second cooling water; and A second pump is installed on the second cooling line and configured to pump the second cooling water. The controller is configured as follows: The second pump's rotational speed (RPM) is controlled to the maximum level.

7. The fuel cell system of claim 6, wherein the first cooling fan is configured to blow external air around the first radiator and the second radiator.

8. The fuel cell system of claim 6, further comprising: A second cooling fan is configured to blow external air around the second radiator.

9. The fuel cell system of claim 6, further comprising: A heat exchanger is disposed on the first cooling line and the second cooling line and configured to perform heat exchange between the first cooling water and the second cooling water.

10. The fuel cell system of claim 1, wherein the controller is configured to: Monitor the temperature of the first cooling water at the inlet of the fuel cell stack; and An alarm is output when the temperature of the first cooling water exceeds the threshold temperature.

11. A method for operating a fuel cell system according to any one of claims 1 to 10, the method comprising: Detect a fault in the first cooling fan, which is configured to blow outside air to the first radiator; When a malfunction of the first cooling fan is detected, the first valve is opened, allowing the first cooling water passing through the fuel cell stack to flow to the fuel cell stack; The blower speed (RPM) of the air conditioning system is controlled to the maximum level. The opening degree of the second valve is controlled based on the cooling degree of the first radiator and the cooling degree of the air conditioning system; and The speed (RPM) of the first pump, configured to pump the first cooling water, is controlled to the maximum level.

12. The method as described in claim 11, characterized in that, The fault detection of the first cooling fan includes: Detect the disabled state of CAN communication; The temperature of the first cooling water was detected to remain unchanged within a specific time period; or The power consumption of the first cooling water was found to remain unchanged within a specific time period.

13. The method of claim 11, further comprising: The temperature control gate is in the open state, allowing cooling air in the air conditioning system to flow towards the heater core.

14. The method of claim 13, further comprising: Depending on whether the fuel cell system includes a condenser, the air conditioner configured to cool the cooling air flowing to the heater core is controlled to be turned on or off.

15. The method of claim 11, further comprising: The rotational speed (RPM) of the second pump is controlled to the maximum level. The second pump is configured to pump a second cooling water through the power electronics components.

16. The method of claim 11, further comprising: Monitor the temperature of the first cooling water at the inlet of the fuel cell stack; and An alarm is output when the temperature of the cooling water exceeds the threshold temperature.

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