Fuel cell system and method of operating the same

Abstract

The present application relates to a fuel cell system and an operating method thereof. A fuel cell system includes a fuel cell stack, a first cooling line having first cooling water passing through the fuel cell stack and circulating therein, a first radiator cooling the first cooling water, an air conditioning system forming a heating circuit with the first cooling line, a first cooling fan blowing outside air toward the first radiator, a first pump pumping the first cooling water, a valve switching a flow path of the first cooling water to the fuel cell stack or the first radiator, and a controller connected to the first cooling fan, the first pump, and the valve and configured to detect a failure of the valve, control revolutions per minute of the first pump and the first cooling fan at respective maximum levels, and control revolutions per minute of a blower of the air conditioning system at a maximum level.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2021-0086397, filed on July 1, 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 can generate electricity by using fuel cell stacks. For example, using hydrogen as fuel for fuel cell stacks may be a solution to global environmental problems, hence the ongoing research and development of fuel cell systems. A fuel cell system may include: a fuel cell stack that generates electricity; a fuel supply device that supplies fuel (hydrogen) to the fuel cell stack; an air supply device that supplies oxygen from the air (as an oxidant necessary for the electrochemical reaction) to the fuel cell stack; and a thermal management system (TMS) that removes the heat of reaction from 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 uses antifreeze liquid circulation for cooling water in a fuel cell system and maintains the fuel cell stack at an appropriate temperature (e.g., 60°C-70°C). It may include a TMS line in which cooling water circulates, a reservoir for storing the cooling water, a pump for circulating the cooling water, an ion filter for removing ions from the cooling water, and a radiator for dissipating the heat from the cooling water to the outside. Furthermore, the thermal management system may include a heater for heating the cooling water and an air conditioning system (e.g., a heater for heating) that uses the cooling water to cool and heat the interior of equipment including the fuel cell system (e.g., a vehicle). The thermal management system can maintain the appropriate temperature for the vehicle's electrical electronic components and the fuel cell stack.

[0006] A fuel cell system may include a valve for regulating the flow path of cooling water, and may include a return spring as an internal component of the valve. Because the valve, including the return spring, is fully open in the direction of the radiator, regardless of the actuator's operation to force the regulation of the flow path, the fuel cell system can ensure cooling even if the valve malfunctions. Summary of the Invention

[0007] This disclosure aims to solve the aforementioned problems in the prior art while fully preserving the advantages achieved by the prior art.

[0008] Recently, measures have been discussed for using valves with the return spring removed in fuel cell systems, particularly for small-sized and lightweight valves. When the function of a valve without a return spring is defective, the fuel cell system may fail to ensure the necessary cooling, and without adequate cooling, the durability of vehicles, construction machinery, or flying objects equipped with fuel cell systems may be compromised, and passenger safety may also be threatened.

[0009] The technical problems to be solved by the present invention are not limited to those described above, and 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 circulating through and within the fuel cell stack; a first radiator disposed on the first cooling line and cooling the first cooling water; an air conditioning system disposed on a first connection line and forming a heating loop with the first cooling line; a first cooling fan blowing outside air toward the first radiator; a first pump disposed on the first cooling line and pumping the first cooling water; a valve switching the flow path of the first cooling water to either the fuel cell stack or the first radiator; and a controller connected to the first cooling fan, the first pump, and the valve, and the controller being configured to detect a malfunction of the valve, control the RPM (revolutions per minute) of the first pump and the RPM of the first cooling fan at maximum levels, and control the RPM of the blower of the air conditioning system at maximum levels.

[0011] According to one aspect of this disclosure, a method for operating a fuel cell system including a fuel cell stack includes: detecting a valve malfunction; switching the flow path of first cooling water to the fuel cell stack or a first radiator based on the degree of valve opening; controlling the RPM of a first pump pumping the first cooling water and the RPM of a first cooling fan blowing outside air toward the first radiator to their maximum values; and controlling the RPM of a blower of an air conditioning system to form a heating loop with a first cooling line, wherein the first cooling water flows. 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 Figure 2B A fuel cell system according to various embodiments is shown, in which first cooling water flows within the fuel cell system;

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

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

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

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

[0019] Figure 7 The structure of an air conditioning system according to various embodiments is shown;

[0020] Figure 8 The diagram illustrates the operation flowcharts according to various embodiments when a valve malfunction is detected; and

[0021] Figure 9 Another operational flowchart is shown according to various embodiments when a valve malfunction is detected.

[0022] Regarding the description of the accompanying drawings, identical or similar parts may be labeled with identical or similar reference numerals. Detailed Implementation

[0023] 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.

[0024] The various embodiments of this disclosure and the terminology used herein are not intended to limit the technical features described herein to any particular embodiment 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 clearly indicates otherwise. As used herein, each of phrases such 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,” and “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 corresponding components from another component and do not limit the components in other respects (e.g., 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 "operationally" or "communically", it means that the element can be coupled to another element directly (e.g., via wire), wirelessly, or via a third element.

[0025] The term "module" as used in the various embodiments of this disclosure can include units configured in hardware, software, or firmware, and is, for example, interchangeable with terms such as logic, logic block, component, or circuit. A module can be an integrated component or the smallest unit or part that performs one or more functions. For example, according to one embodiment, the module can be implemented in the form of an application-specific integrated circuit (ASIC).

[0026] 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 instruction. The one or more instructions may include code produced 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), and with regard to this term, no distinction is made between cases where data is semi-permanently stored in the storage medium and cases where data is temporarily stored in the storage medium.

[0027] According to embodiments, methods according to various embodiments of this disclosure can be provided as included in a computer program product. The computer program product can be transacted between a seller and a buyer. The computer program product can be distributed in the form of a storage medium that can be read by a device (e.g., an optical disc read-only memory (CD-ROM)) or distributed between two user devices via application storage or directly or online (e.g., download or upload). In online distribution, at least a portion of the computer program product can be stored at least temporarily in a storage medium, such as the memory of a manufacturer's server, an app store server, or a relay server, which can be read by a device or temporarily generated.

[0028] According to various embodiments, the elements (e.g., modules or programs) of the above-described components may include one or more entities, and some of these entities may be arranged to be separate from other components. According to various embodiments, one or more elements or operations may be omitted, 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 component. In this case, the integrated component may perform one or more functions of the elements in the multiple components in the same or similar manner as the functions performed by corresponding elements in the multiple components prior to 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.

[0029] Figure 1 and Figure 4 Fuel cell systems according to various embodiments are shown.

[0030] Reference Figure 1 A fuel cell system for a vehicle may include a first cooling line 110 in which first cooling water from the vehicle's fuel cell stack 10 circulates; and a second cooling line in which second cooling water from the vehicle's power electronic components circulates. In an embodiment, the fuel cell system may further include a heat exchanger 300 that exchanges heat between the first and second cooling water, but the heat exchanger 300 may be omitted.

[0031] The fuel cell system may include a first connection line 130, a second connection line 150, and a third connection 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 connection line 130, the second connection line 150, or the third connection line 140. As an example, such as... Figure 2AAs 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 cold start capability under initial vehicle start-up conditions, and as... Figure 2B As shown, a cooling circuit can be formed, in which first cooling water passes through a first radiator 60, allowing heat generated by the fuel cell stack 10 to be dissipated to the outside during vehicle operation. Although not in Figure 2A and Figure 2B As shown, a portion of the first cooling water may flow in the third connecting line 140, and the remainder may pass through the first radiator 60 according to the cooling required by the fuel cell system. 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 ensure start-up capability using the heat from the fuel cell stack 10. The fuel cell stack 10, the first valve 20, the first pump 30, the second valve 40, and the first radiator 60 may be arranged on the first cooling line 110, in which the first cooling water circulates.

[0032] The fuel cell stack 10 (or "fuel cell") may have a structure in which electricity is generated by 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 the electrochemical reaction is attached to the opposite side of an electrolyte membrane through which hydrogen ions travel; a gas diffusion layer (GDL) for uniformly distributing the reactant gases and transferring the generated electrical energy; gaskets and coupling mechanisms for maintaining the airtightness and appropriate coupling pressure of the reactant gases and a first cooling water; and bipolar plates for allowing the reactant gases and the first cooling water to flow.

[0033] In the fuel cell stack 10, hydrogen as fuel and air (oxygen) as oxidant are supplied to the anode and cathode of the membrane electrode assembly. Hydrogen can be supplied to the anode, and air can be supplied to the cathode. The hydrogen supplied to the anode is decomposed into protons and electrons by the catalyst in the electrode layer disposed on the opposite side of the electrolyte membrane. Only hydrogen ions can be transferred to the cathode after selectively passing through the electrolyte membrane, which serves as a cation exchange membrane. Electrons can be transferred to the cathode through the gas diffusion layer and the bipolar plate. In the cathode, the hydrogen ions supplied through the electrolyte membrane and the electrons transferred through the bipolar plate can encounter oxygen in the air supplied to the cathode by the air supply device, and a reaction that produces water can occur. Then, due to the flow of hydrogen ions, electrons can flow through external wires, and an electric current can be generated due to the flow of electrons.

[0034] The first valve 20 can switch the flow path of the first cooling water to either the first connecting line 130 or the fuel cell stack 10 on the first cooling line 110, in which a heater is arranged. 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 selectively switch the flow path of the first cooling water. As an 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, allowing the first cooling water pumped by the first pump 30 to be introduced therein; a second port 22 connected to the first cooling line 110, allowing the first cooling water to be introduced into the fuel cell stack 10 through the first valve 20; and a third port 23 connected to one end of the first connecting line 130. As the second port 22 and the third port 23 of the first valve 20 open and close, the flow path of the first cooling water can be switched to either the heater 50 on 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 connection line 130.

[0035] 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 simultaneously by a 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 passing through the first pump 30 is discharged. In addition, the portion between the outlet of the first pump 30 and the fuel cell stack 10 can be defined as the portion through which 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 from the cooling water outlet (not shown) of the fuel cell stack 10 to the inlet of the first pump 30.

[0036] The first pump 30 may be configured to force the first cooling water to flow. The first pump 30 may include various means for pumping the first cooling water, and the type and number of the first pump 30 are not limited in this disclosure.

[0037] The second valve 40 can switch the flow path of the first cooling water to the fuel cell stack 10 on the first radiator 60 or the first cooling line 110. For example, the second valve 40 can be disposed on the first cooling line 110, located 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 may 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 may be a four-way valve or a three-way valve. When the second valve 40 is a three-way valve, the second valve 40 may include a first port 41 connected to the third connecting line 140, a second port 42 connected to the first cooling line 110 such that the first cooling water through the first radiator 60 is introduced therein, and a third port 44 connected to the first cooling line 110 such that the first cooling water is introduced into the first pump 30, and when the second valve 40 is a four-way valve, the second valve 40 may 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 not introduced into the fuel cell stack 10 through the first radiator 60; 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. A portion of the first cooling water can pass through the first radiator 60, and the remainder can flow along the third connecting line 140 depending on the degree of opening of the second valve 40.

[0038] 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 to heat a heater (not shown) used 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 (the 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 (the point where the other end of the first connecting line 130 is connected to the first cooling line 110).

[0039] 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 connection line 150. Because current flows through the first cooling water, causing a short circuit in the fuel cell stack 10, or when the conductivity of the first cooling water increases due to corrosion or leakage in the system, the first cooling water must maintain low conductivity. The ion filter 95 can be configured to remove ions from the first cooling water to maintain its conductivity at a specific level or lower. In this way, during cold start, 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), and the first cooling water circulates via the heater 50 of the first connection line 130 (heating loop) and also along the second connection line 150, thereby allowing filtration (removal of ions from the first cooling water) by the ion filter 95 installed in the second connection line 150 during cold start. Therefore, it is advantageous to maintain the conductivity of the first cooling water introduced into the fuel cell stack 10 immediately after cold start at a specific level or lower.

[0040] The third connecting line 140 can form a cooling circuit with the first cooling line 110 to cool the first cooling water. As an 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.

[0041] The first radiator 60 can be configured to cool first cooling water. The first radiator 60 can have various structures capable of cooling the first cooling water, and the type and structure of the first radiator 60 are not limited or restricted in this disclosure. The first radiator 60 can be connected to a first reservoir 62, in which the first cooling water is stored.

[0042] The fuel cell system may include a first temperature sensor 112 that measures the temperature of the first cooling water between the fuel cell stack 10 and a first point (first valve 20), a second temperature sensor 114 that measures the temperature of the first cooling water between the other end of the first connection line 130 and the first pump 30, and a third temperature sensor 116 that measures 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 can be controlled to be lower than the preset flow rate. In this way, because 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.

[0043] 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 at least any of the following: 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 control unit (BPCU) 220 that controls a blower (not shown) supplying external air to drive the fuel cell stack 10; a low-voltage DC-DC converter 230 that converts the high-voltage DC received from the high-voltage battery into a low-voltage DC; an air compressor (ACP) 240 that compresses the air supplied to the fuel cell stack 10; and an air cooler 250. Although Figure 1 and Figure 4 As not shown, the power electronic component 200 may further include a DC-DC buck / boost converter.

[0044] A second pump 205 for forcing the flow of the second cooling water can be arranged 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 not limited or restricted.

[0045] A second radiator 70 for cooling the second cooling water can be arranged on the second cooling line 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 not limited or restricted. The second radiator 70 can be connected to a second reservoir 72, in which the second cooling water is stored.

[0046] In an embodiment, such as Figure 1 As shown, the first heat sink 60 and the second heat sink 70 can be cooled simultaneously by a single cooling fan 80. As an example, the first heat sink 60 and the second heat sink 70 can be arranged in parallel, and the cooling fan 80 can be configured to blow outside air towards the first heat sink 60 and the second heat sink 70. Because the first heat sink 60 and the second heat sink 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 heat sink 60 and the second heat sink 70 can be minimized.

[0047] In another 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 arranged separately. In this case, when controlling the RPM of the first cooling fan 80, the fuel cell system can eliminate parameters related to the heat load of the power electronic components 200. The embodiments described below are based on... Figure 1 The structure of the fuel cell system is shown, but the same principle can be applied to... Figure 3 The structure of the fuel cell system.

[0048] Refer again Figure 1 The 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) line, wherein the first cooling water and the second cooling water can flow simultaneously 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 on the TMS line. For example, because 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, the fuel cell system can advantageously reduce the temperature of the first cooling water without increasing the capacity of the first radiator 60 and the cooling fan 80 through heat exchange between the first cooling water and the second cooling water, 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 when vehicles that cannot use driving air (e.g., construction machinery) stop, it is advantageously possible to ensure high-output drive of the fuel cell stack 10 and enhance safety and durability.

[0049] In one embodiment, heat exchanger 300 may 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 may 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 may flow along heat exchanger 300 connected to the first cooling line 110, and the second cooling line 120 may 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 that has passed through the first radiator 60 may be higher than the second temperature of the second cooling water that has passed through the second radiator 70, and the third temperature of the first cooling water that has passed through heat exchanger 300 may be lower than the first temperature. As an 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 passing through the heat exchanger 300 (exchanging heat with the second cooling water) can be 1°C lower than the first temperature.

[0050] according to Figures 1 to 3 In one embodiment, the heat exchanger 300 is arranged separately 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.

[0051] Figure 5A and Figure 5B A first pipe and a second pipe according to various embodiments are shown;

[0052] Reference Figure 5A and Figure 5BThe 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 that exchanges 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 vary depending on desired conditions and design specifications, and this disclosure is not limited to or constrained 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 sealing member 304 (e.g., rubber or silicone material) may be disposed between the first conduit 64 and the second conduit 302. In this way, by providing a sealing member 304 between the first conduit 64 and the second conduit 302, the first channel 64a can be advantageously and stably maintained in place.

[0053] Figure 6 This is a functional block diagram of a fuel cell system according to various embodiments. Figure 7 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.

[0054] 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. In an embodiment, the controller 610 may detect a fault in the first valve 20 or the second valve 40. For example, the controller 610 may detect a fault in the actuator or gear of the first valve 20 (or the second valve 40) via a sensor. As another example, the controller 610 may detect a disabled state of the controller area network (CAN) between the controller 610 and the first valve 20 or the second valve 40.

[0055] The controller 610 can control the configuration of the fuel cell system to ensure the cooling of the fuel cell system, and execute emergency measures when a failure of valve 20 or 40 is detected. To achieve this, the controller 610 may include a first pump controller 614, a second pump controller 616, a cooling fan controller 618, and an air conditioning system controller 620. The configuration included in the controller can be implemented by individual devices (or programs) or can be implemented by an integrated module.

[0056] The first pump controller 614, the second pump controller 616, and the cooling fan controller 618 can respectively control the operation of the first pump 30, the second pump 205, and the cooling fan 80. For example, when a malfunction of valve 20 or 40 is detected, the first pump controller 614 can ensure the flow rate of the first cooling water reaches its maximum level by controlling the RPM of the first pump 30 at its maximum level, and the cooling fan controller 618 can ensure the air flow rate reaches its maximum level by controlling the RPM of the cooling fan 80 at its maximum level. In this way, the fuel cell system can minimize the deterioration of the cooling performance of the first cooling water. The second pump controller 626 can control the RPM of the second pump 205 based on whether the fuel cell system includes a heat exchanger 300. As an example, when the fuel cell system does not include a heat exchanger 300, the second pump controller 626 can minimize the heat radiated by the second radiator 70 by controlling the RPM of the second pump 205 at its minimum level. When the fuel cell system includes a heat exchanger 300, the second pump controller 626 can increase the heat exchange between the first cooling water and the second cooling water by controlling the RPM of the second pump 205 to the maximum level.

[0057] According to an embodiment, when the second cooling fan 85 is further included in the fuel cell system, the cooling fan controller 618 (or a separate cooling fan controller for controlling the second cooling fan 85) can control the RPM of the second cooling fan 85 based on whether the heat exchanger 30 is included in the fuel cell system. For example, when the heat exchanger 300 is included, the cooling fan controller 618 can set the RPM of the second cooling fan 85 to the maximum level to increase heat exchange between the first cooling water and the second cooling water.

[0058] When a malfunction of valve 20 or 40 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 emitted in the heater core 94. For example, refer to Figure 7The 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 flow towards the heater core 94, and temperature gates 93-1 and 93-2, which interrupt the airflow to the heater core 94 by opening and closing the temperature gates 93-1 and 93-2. When a malfunction of valve 20 or 40 is detected, the air conditioning system controller 620 can set the RPM of the blower 92 to the maximum level by causing the cold air generated through the evaporator 91 to flow in a specific direction 705. Furthermore, the air conditioning system controller 620 can direct the airflow that has already passed through the evaporator 91 to the heater core 94 by controlling the opening and closing of the temperature gates 93-1 and 93-2. For example, in the open state, the first temperature gate 93-1 can move downwards, and the second temperature gate 93-2 can move upwards.

[0059] Figure 8 A flowchart illustrating operation when a valve malfunction 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 8 In operation 810, the fuel cell system can detect a fault in at least one of the first valve 20 or the second valve 40.

[0061] In operation 820, the fuel cell stack can set the RPM of the first pump 30 and the cooling fan 80 to the maximum level.

[0062] In operation 830, the fuel cell stack can set the RPM of the blower 92 of the air conditioning system 90 to the maximum level. Additionally, the fuel cell system can open the temperature gate 93, allowing cooling air to flow to the heater core 94.

[0063] According to an embodiment, the fuel cell system may additionally perform operation 840. In operation 840, the fuel cell system may set the RPM of the second pump 205 based on the presence or absence of the heat exchanger 300.

[0064] Figure 9 Another operational flowchart is shown according to various embodiments when a valve malfunction is detected. For example, Figure 9 The operation shown can be Figure 8 Example of operation 820.

[0065] Reference Figure 9In operation 910, the fuel cell system can identify whether heat exchanger 300 is included in the fuel cell system. When heat exchanger 300 is included, in operation 920, the fuel cell system can set the RPM of the second pump 205 to the maximum level to increase heat exchange between the first cooling water and the second cooling water. When heat exchanger 300 is included, in operation 930, the fuel cell system can set the RPM of the second pump 205 to the minimum level to minimize the heat radiated by the second radiator 70.

[0066] According to embodiments of this disclosure, even when valves are faulty (failed) and include small-sized and lightweight valves, the fuel cell system can ensure the cooling of the fuel cell stack for a specific period of time.

[0067] According to embodiments of this disclosure, a fuel cell system can protect vehicles, construction machinery, or flying objects including the fuel cell system, while ensuring time for emergency safety measures and the safety of drivers and passengers in the event of insufficient cooling.

[0068] Furthermore, this disclosure can provide various effects of direct or indirect identification.

Claims

1. A fuel cell system comprising: a fuel cell stack; a first cooling line having a first cooling water that passes through and circulates in the fuel cell stack; a first radiator arranged on the first cooling line and configured to cool the first cooling water; an air conditioning system arranged on a first connection line that forms a heating loop with the first cooling line; a first cooling fan configured to blow external air toward the first radiator; a first pump arranged on the first cooling line and configured to pump the first cooling water; a valve configured to switch a flow path of the first cooling water to the fuel cell stack or the first radiator; and a controller connected to the first cooling fan, the first pump, and the valve, wherein the controller is configured to: detect a failure of the valve; when the failure of the valve is detected, control a number of revolutions per minute of the first pump and a number of revolutions per minute of the first cooling fan at a maximum level; and control a number of revolutions per minute of a blower of the air conditioning system at a maximum level. The controller is further configured to:

2. The fuel cell system of claim 1, wherein, detect a failure of an actuator or a gear of the valve through a sensor attached to the valve; or detect a disabled state of a controller area network between the controller and the valve. The controller is further configured to:

3. The fuel cell system of claim 1, wherein, control a temperature door at an open state so that air cooled by an evaporator of the air conditioning system flows to a heater core.

4. The fuel cell system of claim 1, further comprising: a second cooling line having a second cooling water that passes through and circulates in a power electronics component; a second radiator arranged on the second cooling line and configured to cool the second cooling water; and a second pump arranged on the second cooling line and configured to pump the second cooling water, wherein the controller is further configured to: control a number of revolutions per minute of the second pump at a minimum level. The first cooling fan is arranged to blow the external air around the first radiator and the second radiator.

6. The fuel cell system of claim 1, further comprising:

5. The fuel cell system of claim 4, wherein, a second cooling line having a second cooling water that passes through and circulates in a power electronics component; a second radiator arranged on the second cooling line and configured to cool the second cooling water; a second pump arranged on the second cooling line and configured to pump the second cooling water; and a heat exchanger arranged on the first cooling line and the second cooling line and configured to exchange heat between the first cooling water and the second cooling water, wherein the controller is further configured to: control a number of revolutions per minute of the second pump at a maximum level. The first cooling fan is arranged to blow the external air around the first radiator and the second radiator.

8. The fuel cell system of claim 6, further comprising: a second cooling fan configured to blow the external air around the second radiator, 7. The fuel cell system of claim 6, wherein, ​ ​ ​ wherein the controller is further configured to: control a number of revolutions per minute of the second cooling fan at a maximum level.

9. The fuel cell system of claim 1, wherein, The controller comprises: a cooling fan controller configured to control a number of revolutions per minute of the first cooling fan; a pump controller configured to control a number of revolutions per minute of the first pump; and an air conditioning system controller configured to control a number of revolutions per minute of the blower of the air conditioning system.

10. The fuel cell system of claim 9, wherein, The cooling fan controller, the pump controller, and the air conditioning system controller are integrated into one module.

11. A method for operating a fuel cell system, the fuel cell system comprising a fuel cell stack, the method comprising: detecting a failure of a valve configured to switch a flow path of a first cooling water to the fuel cell stack or a first radiator depending on an opening degree of the valve; and when detecting the failure of the valve: controlling a number of revolutions per minute of a first pump configured to pump the first cooling water and a number of revolutions per minute of a first cooling fan configured to blow external air toward the first radiator at a maximum value; and controlling a number of revolutions per minute of a blower of an air conditioning system forming a heating loop with a first cooling line in which the first cooling water flows at a maximum level. Detecting the failure of the valve comprises: detecting a failure of an actuator or a gear of the valve by a sensor attached to the valve; or 12. The method of claim 11, wherein, detecting a disabled state of a controller area network communication.

13. The method of claim 11, further comprising: controlling a temperature door at an open state so that air cooled by an evaporator flows to a heater core.

14. The method of claim 11, further comprising: controlling a number of revolutions per minute of a second pump configured to pump a second cooling water through power electronics components, wherein controlling the number of revolutions per minute of the second pump comprises: when the fuel cell system includes a heat exchanger configured to exchange heat between the first cooling water and the second cooling water, controlling the number of revolutions per minute of the second pump at a maximum level; and when the fuel cell system does not include the heat exchanger, controlling the number of revolutions per minute of the second pump. ​ ​

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