Method and apparatus for controlling coolant temperature in a fuel cell system

Abstract

The present application discloses a method and device for controlling the coolant temperature in a fuel cell system. A temperature control device and method for a fuel cell system, wherein the device includes: a fuel cell stack, a first pump arranged on a first cooling line, a first radiator arranged on the first cooling line, a power electronic component, a second pump arranged on a second cooling line, a second radiator arranged on the second cooling line, a cooling fan configured to blow external air to any one of the first radiator and the second radiator, and a controller configured to: determine the RPM of the cooling fan based on the coolant temperature at the inlet of the fuel cell stack and the first external air temperature, determine the target cooling performance of the multiple power electronic components based on the power consumption of the multiple power electronic components, and determine the RPM of the second pump based on the target cooling performance of the multiple power electronic components, the RPM of the cooling fan, and the second external air temperature.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2021-0065752 filed on May 21, 2021, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] The following description relates to techniques for controlling coolant temperature in a fuel cell system. Background Art

[0004] A fuel cell system can generate electrical energy by using a fuel cell stack. For example, when hydrogen is used as a fuel for a fuel cell stack, it may be a measure to solve global environmental problems, so research and development of fuel cell systems are constantly ongoing. A fuel cell system may include: a fuel cell stack that generates electrical energy; a fuel supply device that supplies fuel (hydrogen) to the fuel cell stack; an air supply device that supplies oxygen in the air (which serves as an oxidant necessary for the electrochemical reaction) to the fuel cell stack; 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 a water management function.

[0005] The thermal management system is a cooling device that circulates an antifreeze liquid used as a coolant in a fuel cell stack and maintains the fuel cell stack at an appropriate temperature (e.g., 60°C to 70°C), and may include a TMS line in which the coolant circulates, a reservoir that stores the coolant, a pump that circulates the coolant, an ion filter that removes ions included in the coolant, and a radiator that discharges the heat of the coolant to the outside. In addition, the thermal management system may include a heater that heats the coolant and an air conditioning unit (e.g., a heater for heating) that cools and heats the interior of a device (e.g., a vehicle) including a fuel cell system by using the coolant. The thermal management system can maintain the appropriate temperature of the power electronic components of the vehicle as well as the fuel cell stack. Summary of the invention

[0006] This Summary is provided to introduce some concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed claims, nor is it intended to be used as an aid in determining the scope of the claimed claims.

[0007] In one general aspect, a temperature control device for a fuel cell system is provided, comprising: a fuel cell stack; a first cooling circuit configured to circulate a first coolant through the fuel cell stack; a first pump arranged on the first cooling circuit and configured to pump the first coolant; a first radiator arranged on the first cooling circuit and configured to cool the first coolant; a plurality of power electronic components; a second cooling circuit configured to circulate a second coolant through the plurality of power electronic components; a second pump arranged on the second cooling circuit and configured to pump the second coolant; a second radiator arranged on the second cooling circuit and configured to cool the second coolant; a cooling fan configured to blow external air toward any one or any combination of the first radiator and the second radiator; and a controller connected to the first pump, the second pump and the cooling fan, wherein the controller is configured to: determine an RPM of the cooling fan based on a coolant temperature at an inlet of the fuel cell stack and a first external air temperature; determine target cooling performance of the plurality of power electronic components based on power consumption of the plurality of power electronic components; and determine an RPM of the second pump based on the target cooling performance of the plurality of power electronic components, the RPM of the cooling fan and the second external air temperature.

[0008] The controller may be configured to determine the RPM of the second pump based on any one or any combination of target cooling performance of the plurality of power electronic components, the RPM of the cooling fan, the second outside air temperature, an area of ​​the second radiator, and ventilation resistance.

[0009] The controller may be configured to measure power consumption of the plurality of power electronic components, calculate thermal values ​​of the plurality of power electronic components based on the power consumption and inefficiency of the plurality of power electronic components; and determine target cooling performance of the power electronic components by adding the thermal values ​​of the plurality of power electronic components.

[0010] The controller can be configured to store the RPM of the second pump and the RPM of the cooling fan in response to the cooling performance of the power electronic component at the RPM of the second pump satisfying the target cooling performance of the power electronic component; and to increase the RPM of the second pump and the RPM of the cooling fan in response to the cooling performance of the power electronic component at the RPM of the second pump not satisfying the target cooling performance of the power electronic component.

[0011] The controller may be configured to increase the RPM of the second pump in response to the RPM of the second pump being less than a maximum RPM; and increase the RPM of the cooling fan in response to the RPM of the second pump being not less than the maximum RPM.

[0012] The controller may be configured to determine the RPM of the cooling fan based on any one or any combination of coolant temperature at the inlet of the fuel cell stack, the first outside air temperature, the output of the fuel cell stack, efficiency of the fuel cell stack, and the RPM of the first pump.

[0013] The apparatus may include a heat exchanger disposed on the first cooling circuit and the second cooling circuit and configured to exchange heat between the first coolant and the second coolant.

[0014] In another general aspect, a processor-implemented method for operating a fuel cell system is provided, the method comprising: determining an RPM of a cooling fan based on a coolant temperature at an inlet of a fuel cell stack and a first outside air temperature; determining a target cooling performance of the power electronic component based on the power consumption of the power electronic component; and determining an RPM of a pump configured to pump coolant through the power electronic component based on the target cooling performance of the power electronic component, the RPM of the cooling fan, and the second outside air temperature.

[0015] The method may include determining the RPM of the pump based on any one or any combination of a target cooling performance of the power electronic component, an RPM of the cooling fan, a second outside air temperature, an area of ​​a radiator configured to cool the coolant, and a ventilation resistance.

[0016] The method may include measuring power consumption of the power electronic components, calculating thermal values ​​of the power electronic components based on the power consumption and inefficiency of the power electronic components; and determining target cooling performance of the power electronic components by adding the thermal values ​​of the power electronic components.

[0017] The method may include storing the RPM of the pump and the RPM of the cooling fan in response to the cooling performance of the power electronic component at the RPM of the pump satisfying the target cooling performance of the power electronic component; and increasing the RPM of the pump or the RPM of the cooling fan in response to the cooling performance of the power electronic component at the RPM of the pump not satisfying the target cooling performance of the power electronic component.

[0018] The method may include increasing the RPM of the pump in response to the RPM of the pump being less than a maximum RPM; and increasing the RPM of the cooling fan in response to the RPM of the pump being not less than the maximum RPM.

[0019] The method may include determining the RPM of the cooling fan based on any one or any combination of a coolant temperature at an inlet of the fuel cell stack, a first outside air temperature, an output of the fuel cell stack, an efficiency of the fuel cell stack, and an RPM of a pump configured to pump coolant through the fuel cell stack.

[0020] Other features and aspects will be apparent from the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other objects, features and advantages of the present disclosure will become more apparent through the following detailed description in conjunction with the accompanying drawings:

[0022] Figure 1A fuel cell system according to various embodiments is shown;

[0023] Figure 2 A fuel cell system according to various embodiments is shown;

[0024] Figure 3 shows a block diagram of a fuel cell system according to various embodiments;

[0025] Figure 4 shows a workflow of a fuel cell system for managing the temperature of a coolant according to various embodiments;

[0026] Figure 5 A flow chart illustrating operations for determining the RPM of a pump according to various embodiments;

[0027] Figure 6 A flow chart illustrating operations for determining a target cooling performance according to various embodiments; and

[0028] Figure 7 A flow chart illustrating operations for determining the RPM of a pump and the RPM of a cooling fan according to various embodiments.

[0029] With regard to the description of the drawings, the same or similar components may be marked with the same or similar reference numerals. DETAILED DESCRIPTION

[0030] Hereinafter, various embodiments of the present disclosure will be described with reference to the accompanying drawings. Therefore, those skilled in the art will recognize that various modifications, equivalents and / or substitutions may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure.

[0031] The various embodiments of the present disclosure and the terms used herein do not limit the technical features described in the present disclosure to specific embodiments, and should be interpreted as including various modifications, equivalents or replacements of the embodiments. With respect to the description of the drawings, similar components may be represented by similar reference numerals. It should be understood that the singular form of the noun corresponding to the project may include one or more things, unless the relevant context clearly indicates otherwise. As used herein, each of the 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 the items listed together in the corresponding phrases. As used herein, terms such as "1st" and "2nd" or "first" and "second" may be used to simply distinguish the corresponding components from another component, and do not limit the components in other aspects (e.g., importance or order). It should be understood that if an element (e.g., a first element) is referred to as "coupled therewith" or "connected therewith" regardless of whether the term "operationally" or "communicatively" is used, this means that the element may be coupled to another element directly (e.g., by wire), wirelessly or via a third element.

[0032] The term "module" used in various embodiments of the present disclosure may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit, for example. A module may be an integrated component, or a minimum unit or portion that performs one or more functions. For example, according to one embodiment, the module may be implemented in the form of an application specific integrated circuit (ASIC).

[0033] Various embodiments of the present disclosure may be implemented by software (e.g., a program) that includes one or more instructions stored in a storage medium (e.g., an internal memory or an external memory) that can be read by a machine. For example, a device may call at least one instruction of the one or more instructions stored in a storage medium, and may execute the instruction. This allows at least one function to be executed according to at least one of the called instructions. One or more instructions may include code made by a compiler or code executable by an interpreter. A storage medium that can be read by a device 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 a signal (e.g., an electromagnetic wave), and with respect to this term, no distinction is made between a case where data is semi-permanently stored in a storage medium and a case where data is temporarily stored in a storage medium.

[0034] According to an embodiment, the method according to various embodiments of the present disclosure may be provided as included in a computer program product. The computer program product may be traded between a seller and a buyer. The computer program product may be distributed in the form of a storage medium that may be read by a device (e.g., a compact disc read-only memory (CD-ROM)), or may be stored by an application or distributed (e.g., downloaded or uploaded) directly or online between two user devices. In online distribution, at least a portion of the computer program product may be at least temporarily stored in a storage medium, such as a memory of a manufacturer's server, an application store's server, or a relay server, which may be read by a device, or temporarily generated.

[0035] According to various embodiments, the element (for example, module or program) of the above-mentioned element may include one or more entities, and some of the multiple entities may be arranged to be separated from other elements. According to various embodiments, in the above-mentioned element, 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 (for example, module or program) may be integrated into one element. In this case, the integrated element may perform one or more functions in multiple elements in a manner identical or similar to the function performed by the corresponding element in multiple elements before integration. According to various embodiments, the operation performed by a module, program or other element may be performed sequentially, in parallel, repeatedly or heuristically, and one or more operations may be performed or omitted in another order, or one or more other operations may be added.

[0036] Figure 1 and Figure 2 A fuel cell system according to various embodiments is shown.

[0037] Reference Figure 1 , the fuel cell system for a vehicle may include a first cooling circuit 110 in which a first coolant passing through a fuel cell stack 10 of the vehicle circulates, and a second cooling circuit 120 in which a second coolant passing through a power electronic component of the vehicle circulates. In the present embodiment, the fuel cell system may further include a heat exchanger 300 that exchanges heat between the first coolant and the second coolant, but the heat exchanger 300 may be omitted.

[0038] 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 a cooling line with the first cooling line 110. The first coolant 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, the first cooling line 110 may form a heating loop with the first connection line 130 and the third connection line 140 to ensure the cold start capability under the initial start condition of the vehicle, and may form a cooling loop in which the first coolant passes through the first radiator 60 so that the heat generated by the fuel cell stack 10 when the vehicle is running is dissipated to the outside. In another embodiment, when the temperature of the outside air is as high as a specific temperature, the first cooling line 110 does not form a heating loop, and the fuel cell system may ensure the start capability by the heat of 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, and the first coolant circulates in the first cooling line.

[0039] The fuel cell stack 10 (or may be referred to as a "fuel cell") may have a structure in which electricity may be generated by an oxidation / reduction reaction of a 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 an electrochemical reaction is attached to opposite sides of a membrane relative to an electrolyte membrane through which hydrogen ions travel; a gas diffusion layer (GDL) that uniformly distributes a reaction gas and transfers the generated electricity; a gasket and a coupling mechanism for maintaining sealing and an appropriate coupling pressure of the reaction gas and the first coolant; and a bipolar plate that allows the reaction gas and the first coolant to flow.

[0040] In the fuel cell stack 10, hydrogen as a fuel and air (oxygen) as an oxidant are supplied to the anode and cathode of the membrane electrode assembly through the bipolar plate, and 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 of the electrode layer arranged on the opposite side of the electrolyte membrane, wherein only hydrogen ions can be transferred to the cathode after selectively passing through the electrolyte membrane as a cation exchange membrane, and 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 transported through the bipolar plate can meet the oxygen in the air supplied to the cathode by the air supply device, and a reaction to generate water occurs. Then, due to the flow of hydrogen ions, electrons can flow through the external wire, and current can be generated due to the flow of electrons.

[0041] The first valve 20 can switch the flow path of the first coolant to the first connection line 130 (in which the heater 50 is arranged), or 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 connection line 130, and one end of the fuel cell stack 10 on the first cooling line 110. The first valve 20 may include various valve devices that can selectively switch the flow path of the first coolant. As an example, the first valve 20 may be a three-way valve. In this case, the first valve 20 may include a first port 21, which is connected to the first cooling line 110 so that the first coolant pumped by the first pump 30 is introduced therein; a second port 22, which is connected to the first cooling line 110 so that the first coolant passing through the first valve 20 is introduced into the fuel cell stack 10; and a third port 23, which is connected to one end of the first connection line 130. As the second port 22 and the third port 23 of the first valve 20 are opened and closed, the flow path of the first coolant can be switched to the heater 50 or the fuel cell stack 10 of the first connection line 130. That is, when the second port 22 is open and the third port 23 is blocked, the first coolant may be introduced into the fuel cell stack 10 , whereas when the third port 23 is open and the second port 22 is blocked, the first coolant may be introduced into the heater 50 through the first connecting line 130 .

[0042] The first connection line 130 may form a heating loop (heating circulation path) with the first cooling line 110 to heat the first coolant. For example, the first coolant flowing along the first connection line 130 may be heated while passing through the heater 50 installed in the first connection line 130. One end of the first connection line 130 may be connected to the first cooling line 110 at a first point between the outlet of the first pump 30 and the fuel cell stack 10, and the other end of the first connection line 130 may be connected to the first cooling line 110 at a second point between the inlet of the first pump 30 and the fuel cell stack 10. Here, the inlet of the first pump 30 may be defined as an inlet through which the first coolant is introduced into the first pump 30. In addition, the outlet of the first pump 30 may be defined as an outlet through which the first coolant 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 may be defined as a portion where the first coolant discharged from the first pump 30 flows to the first coolant inlet (not shown) of the fuel cell stack 10. In addition, a portion between the inlet of the first pump 30 and the fuel cell stack 10 may be defined as a portion where the first coolant discharged from a coolant outlet (not shown) of the fuel cell stack 10 flows toward the inlet of the first pump 30 .

[0043] The first pump 30 may be configured to force the first coolant to flow. The first pump 30 may include various devices that can pump the first coolant, and the type and number of the first pump 30 are not limited in the present disclosure.

[0044] The second valve 40 may switch the flow path of the first coolant to the first radiator 60 or the fuel cell stack 10 on the first cooling line 110. For example, the second valve 40 may be provided on the first cooling line 110 to be located between the first pump 30 and the first radiator 60, and may be connected to one end of the third connection line 140 and the outlet of the first radiator 60. The second valve 40 may include various valve devices that may selectively switch the flow path of the first coolant 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, it may include a first port 41 connected to the third connection line 140, a second port 42 connected to the first cooling line 110 so that the first coolant passing through the first radiator 60 is introduced therein, and a third port 44 connected to the first cooling line 110 so that the first coolant is introduced into the first pump 30, and when the second valve 40 is a four-way valve, it may further include a third port 43 connected to one end of the second connection line 150. As the first port 41 or the second port 42 of the second valve 40 is opened and closed, the flow path of the first coolant can be switched to the first radiator 60 or the fuel cell stack 10. That is, when the first port 41 is opened and the second port 42 is blocked, the first coolant is introduced into the fuel cell stack 10 without passing through the first radiator 60, and conversely, when the second port 42 is opened and the first port 41 is blocked, the first coolant can be introduced into the fuel cell stack 10 after passing through the first radiator 60.

[0045] The second connection line 150 may form a heating loop with the first cooling line 110 to heat the air conditioning unit (HVAC unit) 90. As an example, the second connection line 150 may form a loop to heat a heater (not shown) for heating the air conditioning unit 90. One end of the second connection line 150 may be connected to the first cooling line 110 between a first point (a point at which one end of the first connection line 130 is connected to the first cooling line 110) and an inlet of the fuel cell stack 10, and a portion of the first coolant may circulate through the second connection line 150. The other end of the second connection line 150 may be connected to the first cooling line 110 between the first pump 30 and a second point (a point at which the other end of the first connection line 130 is connected to the first cooling line 110).

[0046] An ion filter 95 that filters ions of the first coolant passing through the air conditioning unit 90 may be provided in the second connection line 150. Since the current flows in the first coolant, the fuel cell stack 10 is short-circuited, or when the conductivity of the first coolant increases due to corrosion or seepage of the system, the current flows to the first coolant, so the first coolant must maintain low conductivity. The ion filter 95 may be configured to remove ions included in the first coolant to maintain the conductivity of the first coolant at a specific level or lower. In this way, during a cold start in which the supply of the first coolant flowing to the fuel cell stack 10 is interrupted (the second port 22 of the first valve 20 is blocked), the first coolant circulates (warming loop) via the heater 50 of the first connection line 130, and also circulates along the second connection line 150, whereby, during a cold start, it can be filtered (removing ions included in the first coolant) by the ion filter 95 provided in the second connection line 150. Therefore, the conductivity of the first coolant introduced into the fuel cell stack 10 immediately after the cold start can be advantageously maintained at a specific level or lower.

[0047] The third connection line 140 may form a cooling loop with the first cooling line 110 to cool the first coolant. As an example, one end of the third connection line 140 may 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 connection line 140 may be connected to the first cooling line 110 between the coolant outlet of the fuel cell stack 10 and the first radiator 60.

[0048] The first radiator 60 may be configured to cool the first coolant. The first radiator 60 may have various structures that may cool the first coolant, and the type and structure of the first radiator 60 are not limited or defined in the present disclosure. The first radiator 60 may be connected to a first reservoir 62 in which the first coolant is stored.

[0049] The fuel cell system may include a first temperature sensor 112 measuring the temperature of the first coolant between the fuel cell stack 10 and the first point (the first valve 20), a second temperature sensor 114 measuring the temperature of the first coolant between the other end of the first connection line 130 and the first pump 30, and a third temperature sensor 116 measuring the temperature of the coolant in the heater 50. The fuel cell system may control the flow rate of the first coolant 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. As an example, when the measured temperature of the first coolant circulating along the first cooling line 110 is lower than the preset target temperature, the flow rate of the introduced first coolant may be controlled to be lower than the predetermined flow rate. In this way, because the flow rate of the first coolant introduced into the fuel cell stack 10 is controlled to be low when the measured temperature of the first coolant is low, it is advantageously possible to minimize the thermal impact or performance degradation caused by the deviation between the temperature of the first coolant staying inside the fuel cell stack 10 and the temperature of the first coolant introduced into the fuel cell stack 10.

[0050] The second cooling line 120 passes through the power electronic component 200, and the second coolant can circulate along the second cooling line 120. Here, the power electronic component 200 of the vehicle can be understood as a component that uses the power supply of the vehicle as an energy source, and the type and number of the power electronic component 200 are not restricted or limited in the present disclosure. As an example, the power electronic component 200 may include at least any one of the following: a bidirectional high-voltage DC-DC converter (BHDC) 210 arranged between the fuel cell stack 10 and the high-voltage battery (not shown) of the vehicle; a blower pump control unit (BPCU) 220, which controls a blower (not shown) that supplies external air to drive the fuel cell stack 10; a low-voltage DC-DC converter 230, which converts the DC high voltage received from the high-voltage battery into a DC low pressure; an air compressor (ACP) 240, which compresses the air supplied to the fuel cell stack 10; and an air cooler 250. Although Figure 1 and Figure 2 Not shown in the drawing, the power electronic component 200 may further include a DC-DC buck / boost converter.

[0051] The second pump 205 for forcibly flowing the second coolant may be disposed on the second cooling line 120. The second pump 205 may include a pumping device that can pump the second coolant, and the type and features of the second pump 205 are not limited or restricted.

[0052] The second radiator 70 for cooling the second coolant may be arranged on the second cooling line 120. The second radiator 70 may have various structures that may cool the second coolant, and the type and structure of the second radiator 70 are not limited or restricted. The second radiator 70 may be connected to a second reservoir 72 in which the second coolant is stored.

[0053] In this embodiment, if Figure 1 As shown, the first radiator 60 and the second radiator 70 may be cooled simultaneously by one cooling fan 80. As an example, the first radiator 60 and the second radiator 70 may be arranged in parallel, and the cooling fan 80 may be configured to blow external air toward the first radiator 60 and the second radiator 70. Since the first radiator 60 and the second radiator 70 are cooled simultaneously by one cooling fan 80, the structure of the fuel cell system may be simplified, the degree of freedom in design and the space utilization may be improved, and the power consumption for cooling the first radiator 60 and the second radiator 70 may be minimized. The structure of the cooling fan 80 may be referred to as a "dual type".

[0054] In one embodiment, Figure 2 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 may be arranged separately. In this case, when controlling the RPM of the first cooling fan 80, the fuel cell system can exclude parameters related to the heat load of the power electronic component 200. The structure of the cooling fans 80 and 85 may be referred to as "polytype".

[0055] The heat exchanger 300 may be configured to exchange heat between the first coolant and the second coolant. When the heat exchanger 300 is included, the first cooling circuit 110 and the second cooling circuit 120 may constitute a thermal management system (TMS) circuit, in which the first coolant and the second coolant may flow while exchanging heat, and in this case, the first coolant or the second coolant may be used as a refrigerant or a heat medium on the TMS circuit. For example, because the temperature of the second coolant for cooling the power electronic components is lower than the temperature of the first coolant for cooling the fuel cell stack 10, advantageously, the fuel cell system can reduce the temperature of the first coolant by heat exchange between the first coolant and the second coolant without increasing the capacity of the first radiator 60 and the cooling fan 80, the cooling efficiency of the fuel cell stack 10 can be improved, and safety and reliability can be improved. In addition, because the fuel cell system can reduce the temperature of the first coolant when a vehicle (e.g., a construction machine) that cannot use driving wind stops, it is advantageously possible to ensure a high output drive of the fuel cell stack 10, and safety and durability can be improved.

[0056] In an embodiment, the heat exchanger 300 may be connected to the first cooling line 110 between the outlet of the first radiator 60 and the fuel cell stack 10, and the second cooling line 120 may connect the outlet of the second radiator 70 and the power electronic components to pass through the heat exchanger 300. For example, the first coolant may flow along the heat exchanger 300 connected to the first cooling line 110, and the second cooling line 120 may pass through the inside of the heat exchanger 300 to be exposed to the first coolant (for example, the first coolant flows along the circumference of the second cooling line 120). In this way, the fuel cell system can reduce the temperature of the first coolant introduced into the fuel cell stack 10 through heat exchange between the first coolant and the second coolant. The first temperature of the first coolant passing through the first radiator 60 may be higher than the second temperature of the second coolant passing through the second radiator 70, and the third temperature of the first coolant passing through the heat exchanger 300 may be lower than the first temperature. As an example, the first temperature of the first coolant may be about 10° C. higher than the second temperature of the second coolant, and the third temperature of the first coolant passing through the heat exchanger 300 (heat-exchanging with the second coolant) may be 1° C. lower than the first temperature.

[0057] according to Figure 1 and Figure 2 The heat exchanger 300 is arranged separately from the first radiator 60, but in another embodiment, 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 position (upper left end) of the first radiator 60, but the present disclosure is not limited thereto.

[0058] Since a vehicle such as a construction machine requires a high output even when the vehicle is stopped, the fuel cell system according to the embodiment may determine the RPM of the second pump 205 in consideration of the RPM of the cooling fan 80 or 85, the outside air temperature, and the target cooling performance of the power electronic component 200. In addition, since the fuel cell system may determine the RPM of the second pump 205 in consideration of at least one of the arrangement of the heat exchanger 300, the structure of the cooling fan (e.g., dual type or multi type), and the amount of introduced air of the radiators 60 and 70, the cooling performance of the fuel cell system in which the first cooling circuit 110 and the second cooling circuit 120 exist together may be optimized.

[0059] Figure 3 A block diagram of a fuel cell system according to various embodiments is shown. Figure 3 The configuration shown may be a hardware device or a program (or application) including instructions.

[0060] Reference Figure 3 , the temperature measurer 312 may include Figure 1 and Figure 2At least one of the temperature sensors 112, 114, and 116 is shown. The temperature measurer 312 may measure the temperature of the coolant passing through the fuel cell stack 10 or the power electronic component 200. The power consumption measurer 314 may measure the power consumption of the power electronic component 200. The external air temperature measurer 316 may measure the external air temperature of the fuel cell system in a specific cycle.

[0061] The controller 320 may be a hardware device, such as a processor or a central processing unit (CPU), or a program implemented by a processor. The controller 320 may determine the RPM of the first pump 30, the cooling fan 80 or 85, and the second pump 205 based on the information measured by the temperature measurer 312, the power consumption measurer 314, and the external air temperature measurer 316. To implement this, the controller 320 may include a first target cooling performance calculator 321, a second target cooling performance calculator 322, a cooling fan controller 323, a first pump controller 324, and a second pump controller 325. The first target cooling performance calculator 321 may calculate the target cooling performance of the fuel cell stack 10 based on the output and efficiency of the fuel cell stack 10. The second target cooling performance calculator 322 may calculate the target cooling performance of the power electronic component 200 based on the power consumption and inefficiency of the power electronic component 200. The cooling fan controller 323 may determine the RPM of the cooling fan 80 or 85, the first pump controller 324 may determine the RPM of the first pump 30, and the second pump controller 325 may determine the RPM of the second pump 205. In an embodiment, the configurations included in the controller 320 may be implemented by separate modules, chips, or programs, or may be implemented by one integrated module.

[0062] Figure 4 A workflow of a fuel cell system for managing the temperature of a coolant according to various embodiments is shown.

[0063] refer to Figure 4 , the controller 320 may determine the RPM of the cooling fan 80 based on the coolant temperature at the inlet of the fuel cell stack 10 and the outside air temperature (first outside air temperature), determine the target cooling performance of the power electronic components 200 based on the power consumption of the plurality of power electronic components 200, and determine the RPM of the second pump 205 based on the outside air temperature (second outside air temperature) measured again, the RPM of the cooling fan 80, and the target cooling performance of the power electronic components 200. The controller 320 may determine the flow rate of the second coolant that satisfies the target cooling performance of the power electronic components 200, and may determine the RPM of the second pump 205 based on the determined flow rate. When the fuel cell system includes multiple types of cooling fans 80 and 85, the controller 320 may determine the RPM of the second pump 205 by using the RPM of the cooling fan 85.

[0064] The controller 320 may store in a database table information (eg, a lookup table) representing the relationship between the target cooling performance of the power electronic component 200, the RPM of the cooling fan 80, the outside air temperature, and the RPM of the second pump 205. For example, the table information may be represented in Table 1 as follows.

[0065] [Table 1]

[0066]

[0067] In Table 1, the target cooling performance and the RPM of the cooling fan may have a relationship of 0<A<B and 0<a<b. Since the performance of the second pump 205 is limited, the controller 320 may set the RPM of the second pump 205 at a specific level or higher to the maximum RPM, and conversely, since the cooling performance is not affected when the second pump 205 rotates at a specific level or lower, the controller 320 may set the RPM of the second pump 205 at a specific level or lower to the minimum RPM. The values ​​representing the external air temperature, the target cooling performance, and the RPM of the cooling fan are discrete, and thus values ​​between the values ​​represented in the table information may be processed by interpolation.

[0068] The controller 320 may determine the RPM of the cooling fan 80 based on at least one of the target cooling performance of the fuel cell stack 10 and the RPM of the first pump 30. In this case, the controller 320 may determine the target cooling performance of the fuel cell stack 10 based on the output and efficiency of the fuel cell stack 10, and may determine the RPM of the first pump 30 based on the determined target cooling performance and the coolant temperature at the outlet of the fuel cell stack 10.

[0069] The controller 320 may determine the target cooling performance of the power electronic component 200 based on the power consumption and inefficiency of the power electronic component 200. For example, the second target cooling performance calculator 322 may determine the target cooling performance (CP) of the power electronic component 200 by Equation 1 as follows.

[0070] Equation 1

[0071] CP=a(power 1 (1-Eff 1 )+power 2 (1-Eff 2 )+power 3 (1-Eff 3 )

[0072] +…power n (1-Eff n )

[0073] In Equation 1, power nrepresents the power consumption of the configuration of the power electronic component 200 (e.g., 210, 220, 230, 240, and 250), “1-Eff n ” represents inefficiency of the configuration of the power electronic component 200 , and “a” represents a weight. N is a natural number and may be changed according to the number of configurations of the power electronic component 200 .

[0074] Because even if the controller 320 is a dual type (in which the radiators 60 and 70 share the cooling fan 80), the amount of air introduced into the radiators 60 and 70 may differ depending on the area and ventilation resistance of the radiators 60 and 70. According to the embodiment, the controller 320 can calculate the amount of air introduced into the second radiator 70 taking into account the RPM of the cooling fan 80 and the area and ventilation resistance of the second radiator 70, and can further determine the RPM of the second pump 205 taking into account the calculated amount of introduced air.

[0075] When the RPM of the second pump 205 is maximum, the controller 320 may increase the RPM of the cooling fan 80 to ensure cooling performance of the power electronic component 200. When the RPM of the cooling fan 80 is also maximum, the fuel cell system may further include a heat exchanger 300 to exchange heat between the first coolant and the second coolant.

[0076] Figure 5 A flowchart of an operation of determining the RPM of a pump according to various embodiments is shown. The operation described below may be implemented by the fuel cell system, or may be implemented by a configuration (eg, controller 320) included in the fuel cell system.

[0077] refer to Figure 5 In operation 510 , the controller 320 may determine the RPM of the cooling fan 80 based on the coolant temperature at the inlet of the fuel cell stack 10 and the first outside air temperature.

[0078] In operation 520, the controller 320 may calculate the amount of air introduced into the second radiator 70 based on the area and ventilation resistance of the second radiator 70. According to an embodiment, the controller 320 may omit operation 520.

[0079] In operation 530 , the controller 320 may determine a target cooling performance of the power electronic component 200 based on the power consumption thereof.

[0080] In operation 540, the controller 320 may determine the RPM of the second pump 205 based on the target cooling performance of the power electronic component 200, the RPM of the cooling fan 80, and the second outside air temperature. The second outside air temperature may be an outside air temperature measured after measuring the first outside air temperature.

[0081] Figure 6A flow chart illustrating operations for determining a target cooling performance according to various embodiments is shown. Figure 6 The operations shown can be Figure 3 An example of operation 530 is shown.

[0082] Reference Figure 6 In operation 610 , the controller 320 may measure power consumption of the power electronic component 200 . The power electronic component 200 may refer to a plurality of configurations, and in this case, the controller 320 may measure power consumption of each of the plurality of power electronic components 200 .

[0083] In operation 620 , the controller 320 may calculate a thermal value of each power electronic component 200 based on the measured power consumption and low (1-efficiency) of the power electronic component.

[0084] In operation 630 , the controller 320 may determine target cooling performance of all power electronic components 200 by adding the calculated heat values.

[0085] Figure 7 A flow chart illustrating operations for determining the RPM of a pump and the RPM of a cooling fan according to various embodiments.

[0086] refer to Figure 7 , in operation 710 , the controller 320 may measure an external air temperature (eg, a second external air temperature).

[0087] In operation 720, the controller 320 may determine the RPM of the second pump 205 based on the outside air temperature and the RPM of the cooling fan 80 (eg, Figure 5 Operation 540).

[0088] In operation 730, the controller 320 may identify whether the cooling performance of the power electronic component 200 at the determined RPM satisfies the target cooling performance of the second pump 205. When the cooling performance of the power electronic component satisfies the target cooling performance, in operation 740, the controller 320 may store the determined RPM of the second pump 205 and the RPM of the cooling fan 80. The controller 320 may control the operations of the second pump 205 and the cooling fan 80 based on the stored RPM.

[0089] When the cooling performance of the power electronic components does not satisfy the target cooling performance, the controller 320 may identify whether the RPM of the second pump 205 is the maximum RPM or more in operation 750. When the RPM of the second pump 205 is less than the maximum RPM, the controller 320 may increase the RPM of the second pump 205 and repeat operations 710 to 730 in operation 760. When the RPM of the second pump 205 is the maximum RPM or more, the controller 320 may increase the RPM of the cooling fan 80 and repeat operations 710 to 730 in operation 770.

[0090] A vehicle including a fuel cell system requires a high output of the fuel cell when the vehicle is driven, but the fuel cell can be cooled by driving wind. Meanwhile, construction machinery performs leveling or loading operations even when stopped, and the fuel cell or power electronic components require a high output, but since there is basically no driving wind, the overall cooling efficiency may be insufficient. When the cooling efficiency is insufficient, the temperature of the coolant rises, which may seriously affect the safety and durability of the fuel cell and the power electronic components. According to an embodiment of the present disclosure, the fuel cell system can ensure a high output of the fuel cell and ensure safety and durability.

[0091] According to the embodiments of the present disclosure, the fuel cell system can ensure cooling performance and prevent the life of electronic components from being deteriorated by effectively controlling thermal management of power electronic components.

[0092] Although the present disclosure includes specific examples, after understanding the disclosure of the present application, it will be apparent that various changes in form and detail can be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are considered to be descriptive only and not for limiting purposes. The description of the features or aspects in each example should be considered to apply to similar features or aspects in other examples. If the described techniques are performed in a different order, and / or if the components in the described systems, architectures, devices, or circuits are combined in different ways, and / or replaced or supplemented by other components or their equivalents, suitable results can be achieved. Therefore, the scope of the present disclosure is not limited by the detailed description, but by the claims and their equivalents, and all changes within the scope of the claims and their equivalents should be interpreted as included in the present disclosure.

Claims

1. A temperature control device for a fuel cell system, comprising: Fuel cell stack; a first cooling circuit configured to circulate a first coolant through the fuel cell stack; a first pump disposed on the first cooling circuit, and the first pump is configured to pump the first coolant; a first radiator disposed on the first cooling circuit, and the first radiator is configured to cool the first coolant; Multiple power electronic components; a second cooling circuit configured to circulate a second coolant through the plurality of power electronic components; a second pump disposed on the second cooling circuit, and the second pump is configured to pump the second coolant; a second radiator disposed on the second cooling circuit, and the second radiator is configured to cool the second coolant; a cooling fan configured to blow external air toward the first radiator and the second radiator; as well as a controller connected to the first pump, the second pump and the cooling fan, Wherein, the controller is configured as: determining an RPM of the cooling fan based on a coolant temperature at an inlet of the fuel cell stack and a first outside air temperature; determining target cooling performance of the plurality of power electronic components based on power consumption of the plurality of power electronic components; and The RPM of the second pump is determined based on the target cooling performance of the plurality of power electronic components, the RPM of the cooling fan, and a second outside air temperature, wherein the second outside air temperature is an outside air temperature measured after measuring the first outside air temperature.

2. The temperature control device according to claim 1, wherein: The RPM of the second pump is determined further based on the area and / or ventilation resistance of the second radiator.

3. The temperature control device according to claim 1, wherein: The controller is further configured to: measuring power consumption of the plurality of power electronic components; calculating a thermal value of the plurality of power electronic components based on power consumption and inefficiency of the plurality of power electronic components; as well as The target cooling performance of the power electronic components is determined by adding the heat values ​​of the plurality of power electronic components.

4. The temperature control device according to claim 1, wherein: The controller is further configured to: In response to the cooling performance of the power electronic component at the RPM of the second pump satisfying the target cooling performance of the power electronic component, storing the RPM of the second pump and the RPM of the cooling fan; and In response to the cooling performance of the power electronic component at the RPM of the second pump not satisfying the target cooling performance of the power electronic component, the RPM of the second pump and the RPM of the cooling fan are increased.

5. The temperature control device according to claim 4, wherein: The controller is further configured to: In response to the RPM of the second pump being less than a maximum RPM, increasing the RPM of the second pump; and In response to the RPM of the second pump being not less than the maximum RPM, the RPM of the cooling fan is increased.

6. The temperature control device according to claim 1, wherein: The controller is further configured to: The RPM of the cooling fan is further determined based on at least one of an output of the fuel cell stack, an efficiency of the fuel cell stack, and an RPM of the first pump.

7. The temperature control device according to claim 1, further comprising: A heat exchanger is disposed on the first cooling circuit and the second cooling circuit, and the heat exchanger is configured to perform heat exchange between the first coolant and the second coolant.

8. A processor-implemented method for operating a fuel cell system, the fuel cell system comprising a fuel cell stack; a first cooling circuit configured to circulate a first coolant through the fuel cell stack; a first radiator disposed on the first cooling circuit, and the first radiator is configured to cool the first coolant; Multiple power electronic components; a second cooling circuit configured to circulate a second coolant through the plurality of power electronic components; a pump disposed on the second cooling circuit, and the pump is configured to pump the second coolant; a second radiator disposed on the second cooling circuit, and the second radiator is configured to cool the second coolant; A cooling fan is configured to blow external air toward the first radiator and the second radiator, and the method includes: determining an RPM of the cooling fan based on a coolant temperature at an inlet of the fuel cell stack and a first outside air temperature; determining a target cooling performance of the power electronic component based on the power consumption of the power electronic component; and The RPM of the pump is determined based on the target cooling performance of the power electronic component, the RPM of the cooling fan, and a second outside air temperature, wherein the second outside air temperature is an outside air temperature measured after the first outside air temperature is measured.

9. The method according to claim 8, wherein: The RPM of the pump is further determined based on an area and / or ventilation resistance of a radiator configured to cool the coolant.

10. The method according to claim 8, wherein: Determining the target cooling performance of the power electronic component comprises: measuring the power consumption of the power electronic component; calculating a thermal value of the power electronic component based on the power consumption and inefficiency of the power electronic component; and The target cooling performance of the power electronic components is determined by adding the calorific values ​​of the power electronic components.

11. The method according to claim 8, further comprising: in response to the cooling performance of the power electronic component at the RPM of the pump satisfying the target cooling performance of the power electronic component, storing the RPM of the pump and the RPM of the cooling fan; and In response to the cooling performance of the power electronic component at the RPM of the pump not satisfying the target cooling performance of the power electronic component, the RPM of the pump or the RPM of the cooling fan is increased.

12. The method according to claim 11, wherein: The increase in the RPM of the pump or the RPM of the cooling fan comprises: In response to the RPM of the pump being less than a maximum RPM, increasing the RPM of the pump; and In response to the RPM of the pump being not less than the maximum RPM, the RPM of the cooling fan is increased.

13. The method according to claim 8, wherein: The RPM of the cooling fan is further determined based on at least one of an output of the fuel cell stack, an efficiency of the fuel cell stack, an RPM of the pump configured to pump the coolant through the fuel cell stack.

14. A non-transitory computer-readable storage medium storing instructions which, when executed by a processor, cause the processor to perform the method of claim 8.

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