KR20230153837A - Fuel cell system and heating control method thereof - Google Patents

Abstract

A fuel cell system according to an embodiment of the present invention includes a cooling fan that sucks heated air discharged from a radiator and transfers it to an indoor heating duct, and an actuator that rotates a damper door on the flow path so that the air introduced into the duct is discharged indoors. , and a control unit that controls the rotation angle of the actuator based on the temperature of the discharge air of the radiator.

Description

Fuel cell system and heating control method thereof {FUEL CELL SYSTEM AND HEATING CONTROL METHOD THEREOF}

The present invention relates to a fuel cell system and its heating control method.

A fuel cell system can generate electrical energy using a fuel cell stack. For example, if hydrogen is used as a fuel for a fuel cell stack, it can be an alternative to solving global environmental problems, so continuous research and development is being conducted on fuel cell systems.

The fuel cell system consists of 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 from the air, an oxidizing agent necessary for electrochemical reactions, to the fuel cell stack, and fuel. It may include a thermal management system (TMS) that removes reaction heat from the cell stack to the outside of the system, controls the operating temperature of the fuel cell stack, and performs a water management function.

The thermal management system is a type of cooling device that maintains an appropriate temperature (e.g., 60 to 70°C) by circulating antifreeze, which acts as coolant, into the fuel cell stack. It includes a TMS line through which the coolant circulates, and a reservoir where the coolant is stored. , a pump that circulates the coolant, an ion filter that removes ions contained in the coolant, and a radiator that emits heat from the coolant to the outside. Additionally, the thermal management system may include a heater that heats coolant, and an air conditioning unit that uses coolant to cool or heat the interior of a device (eg, vehicle) containing a fuel cell system.

As an example, the air conditioning unit may include an electric heater for heating the interior of a vehicle including a fuel cell system. PTC (Positive Temperature Coefficient) heaters are widely used as electric heaters. PTC heaters are capable of rapid heat generation, so they can easily raise the room temperature, and heating can be easily controlled with simple control logic.

However, PTC heaters operate by receiving power from a battery or fuel cell, and require a lot of power to heat the room, which can lead to problems with reduced fuel efficiency, such as shortened driving distance.

One object of the present invention is to provide a fuel cell system and a heating control method thereof that minimize the power consumption of the PTC heater and increase fuel efficiency by using the waste heat of the coolant used to cool the fuel cell stack in the fuel cell system for indoor heating. It is provided.

In addition, another object of the present invention is to reduce costs by eliminating parts such as HVAC (Heating Ventilation and Air Conditioning) blowers and heater cores (HTR CORE) by using the cooling fan of the radiator as a blower of the heating unit, and to reduce costs by using the cooling fan of the radiator as a blower of the heating unit. To provide a fuel cell system and a heating control method thereof that increase coolant pump efficiency by minimizing .

In addition, another object of the present invention is to provide a fuel cell system and a heating control method thereof that can reduce the overall size of the fuel cell system by configuring the cooling fan in a small fuel cell system as a multi-blade blower fan.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

A fuel cell system according to an embodiment of the present invention includes a cooling fan that sucks heated air discharged from a radiator and transfers it to an indoor heating duct, and an actuator that rotates a damper door on the flow path so that the air introduced into the duct is discharged indoors. , and a control unit that controls the rotation angle of the actuator based on the temperature of the discharge air of the radiator.

In one embodiment, the fuel cell system according to the present invention further includes a first temperature sensor that measures the indoor temperature, and a second temperature sensor that measures the temperature of discharge air from the radiator.

In one embodiment, when the indoor temperature is below the target temperature during indoor heating and the discharge air temperature of the radiator exceeds the indoor temperature, the control unit adjusts the rotation angle of the actuator to control the air discharged into the room. It is characterized by controlling the amount of air.

In one embodiment, the control unit adjusts the rotation angle of the actuator in a direction in which the damper door on the flow path is opened when the indoor temperature falls below a predetermined temperature during indoor heating.

In one embodiment, the control unit controls power supply to the PTC heater when the indoor temperature is below the target temperature and the discharge air temperature of the radiator is below the indoor temperature during indoor heating.

In one embodiment, the PTC heater is disposed at the outlet of the duct and heats air discharged into the room along the flow path when the power is supplied.

In one embodiment, the control unit blocks power supply to the PTC heater when the discharge air temperature of the radiator exceeds the room temperature.

In one embodiment, the control unit is characterized in that when the indoor temperature exceeds the target temperature during indoor heating, the control unit operates in standby mode.

In one embodiment, the cooling fan is characterized by being composed of a multi-blade blower fan.

In one embodiment, the cooling fan blows outside air to the radiator disposed on a cooling line through which coolant passing through the fuel cell stack circulates, and when heating the room, it sucks in heated air discharged from the radiator and blows it into the duct. It is characterized by transport.

In addition, a heating control method of a fuel cell system according to an embodiment of the present invention includes the steps of sucking heated air discharged from a radiator by a cooling fan and transferring it to an indoor heating duct, and discharging the air introduced into the duct into the room. Preferably, it includes controlling an actuator that rotates a damper door on the flow path, and controlling a rotation angle of the actuator based on the discharge air temperature of the radiator.

In one embodiment, the heating control method according to the present invention further includes measuring the indoor temperature from a first temperature sensor, and measuring the discharge air temperature of the radiator from a second temperature sensor. .

In one embodiment, the step of controlling the rotation angle of the actuator includes controlling the rotation angle of the actuator when the indoor temperature is below the target temperature during indoor heating and the discharge air temperature of the radiator exceeds the indoor temperature. It is characterized in that it includes the step of controlling the amount of air discharged into the room by adjusting.

In one embodiment, the step of controlling the rotation angle of the actuator includes adjusting the rotation angle of the actuator in a direction in which the damper door on the flow path is opened when the indoor temperature during indoor heating falls below a predetermined temperature. It is characterized in that it further includes.

In one embodiment, the heating control method according to the present invention includes the steps of controlling power supply to the PTC heater when the indoor temperature is below the target temperature and the discharge air temperature of the radiator is below the indoor temperature during indoor heating. , and the step of the PTC heater heating the air discharged into the room along the flow path.

In one embodiment, the heating control method according to the present invention further includes the step of blocking power supply to the PTC heater when the discharge air temperature of the radiator exceeds the room temperature.

In one embodiment, the heating control method according to the present invention further includes operating in standby mode when the indoor temperature exceeds the target temperature during indoor heating.

In one embodiment, the heating control method according to the present invention further includes the step of the cooling fan blowing outside air to the radiator disposed on the cooling line through which coolant circulating through the fuel cell stack is used, The heated air discharged from the radiator is sucked in and transferred to the duct.

According to embodiments of the present invention, the waste heat of the coolant used to cool the fuel cell stack in the fuel cell system is used for indoor heating, thereby minimizing the power consumption of the PTC heater and increasing fuel efficiency.

In addition, according to embodiments of the present invention, by using the cooling fan of the radiator as a blower of the heating unit, it is possible to secure space and reduce costs by removing parts such as HVAC blowers and heater cores (HTR CORE), and to reduce costs by removing parts such as HVAC blowers and heater cores (HTR CORE). This has the effect of increasing coolant pump efficiency by minimizing .

Additionally, according to embodiments of the present invention, the overall size of the fuel cell system can be reduced by configuring the cooling fan in the fuel cell system as a multi-blade blower fan.

1 is a diagram illustrating a fuel cell system according to an embodiment of the present invention.
Figure 2 is a diagram showing a fuel cell system according to another embodiment of the present invention.
Figure 3 is a diagram illustrating a fuel cell system according to various further embodiments of the present invention.
Figure 4 is a diagram showing a heating structure of a fuel cell system according to an embodiment of the present invention.
Figure 5 is a diagram showing a control block diagram of a fuel cell system according to an embodiment of the present invention.
FIG. 6 is a diagram illustrating the operation flow of a heating control method of a fuel cell system according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail through illustrative drawings. When adding reference numerals to components in each drawing, it should be noted that identical components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing embodiments of the present invention, if detailed descriptions of related known configurations or functions are judged to impede understanding of the embodiments of the present invention, the detailed descriptions will be omitted.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. Additionally, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted in an ideal or excessively formal sense unless explicitly defined in the present application. No.

1 to 3 show fuel cell systems according to various embodiments. FIG. 1 is a diagram showing a fuel cell system according to an embodiment of the present invention, and FIGS. 2 and 3 show other embodiments. This is a diagram showing a fuel cell system.

Referring to FIG. 1, the fuel cell system for a vehicle is configured such that the first coolant circulates through the fuel cell stack 10 of the vehicle and passes through the first cooling line 110 and power electronic parts 200 of the vehicle. It may include a second cooling line 120 through which a second coolant is circulated. In an embodiment, the fuel cell system may further include a heat exchanger 300 that exchanges heat between the first coolant and the second coolant, but may be omitted.

The fuel cell system forms a heating loop (heating circulation path, or heating loop) with the first cooling line 110, or a first connection line 130 and a first connection line 130 to form a cooling line with the first cooling line 110. It may include a second connection line 140. The first coolant may be cooled or heated while circulating through the first connection line 130 or the second connection line 140. As an example, the first cooling line 110 forms a heating loop with the first connection line 130 and the second connection line 140 to secure cold start capability in the initial starting state of the vehicle, and the fuel cell operates during driving. A cooling loop through which the first coolant passes through the first radiator 60 may be formed so that heat generated in the stack 10 can be discharged to the outside. Additionally, depending on the amount of cooling required for the fuel cell system, part of the first coolant may flow into the second connection line 140 and the remaining part may pass through the first radiator 60.

In another embodiment, when the outside air is as high as a specified temperature, the first cooling line 110 does not form a heating loop and the fuel cell system can secure starting ability through the heat of the fuel cell stack 10.

On the first cooling line 110 through which the first coolant circulates, a fuel cell stack 10, a first valve 20, a first pump 30, a second valve 40, and a first radiator 60 are installed. can be placed.

The fuel cell stack 10 (or may be referred to as a 'fuel cell') is a structure capable of producing electricity through a redox reaction of fuel (eg, hydrogen) and an oxidizing agent (eg, air). can be formed. As an example, the fuel cell stack 10 is a membrane electrode assembly (MEA) with catalyst electrode layers where electrochemical reactions occur on both sides of the electrolyte membrane through which hydrogen ions move, and evenly distributes the reaction gases. A gas diffusion layer (GDL) that plays a role in transmitting the generated electrical energy, a gasket and fastening device to maintain the airtightness and appropriate fastening pressure of the reaction gases and the first coolant, and the reaction gases and the first coolant. It may include a bipolar plate that moves coolant.

In the fuel cell stack 10, hydrogen as a fuel and air (oxygen) as an oxidizing agent are supplied to the anode and cathode of the membrane electrode assembly through the flow path of the separator, respectively. Hydrogen is supplied to the anode, and air is supplied to the anode. can be supplied to the cathode. The hydrogen supplied to the anode is decomposed into hydrogen ions (protons) and electrons (electrons) by the catalyst in the electrode layer formed on both sides of the electrolyte membrane, and only hydrogen ions are selectively passed through the electrolyte membrane, which is a cation exchange membrane, and transferred to the cathode. At the same time, electrons can be transferred to the cathode through the conductive gas diffusion layer and separator plate. At the cathode, hydrogen ions supplied through the electrolyte membrane and electrons transferred through the separator meet oxygen in the air supplied to the cathode by the air supply device, causing a reaction to generate water. Due to the movement of hydrogen ions that occurs at this time, a flow of electrons occurs through the external conductor, and current can be generated through this flow of electrons.

The first valve 20 may change the flow path of the first coolant on the first cooling line 110 to the first connection line 130 or the fuel cell stack 10 where the heater 50 is disposed. The first valve 20 may include various valve means that can selectively change the flow path of the first coolant. For example, the first valve 20 may be a three-way valve. In this case, the first valve 20 includes a first port 21 connected to the first cooling line 110 so that the first coolant pumped by the first pump 30 flows in, and a first valve 20. A second port 22 connected to the first cooling line 110 so that the first coolant passing through flows into the fuel cell stack 10, and a third port connected to one end of the first connection line 130 ( 23) may be included. By opening and closing the second port 22 and the third port 23 of the first valve 20, the flow path of the first coolant is connected to the heater 50 or the fuel cell stack 10 of the first connection line 130. can be converted to

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.

The first pump 30 may be set to forcibly flow the first coolant. The first pump 30 may include various means for pumping the first coolant, and the type and number of the first pump 30 are not limited in this document.

The second valve 40 may change the flow path of the first coolant on the first cooling line 110 to the first radiator 60 or the fuel cell stack 10. For example, the second valve 40 is provided on the first cooling line 110 to be located between the first pump 30 and the first radiator 60, and is connected to one end of the second connection line 140. And it may be connected to the outlet of the first radiator 60. The second valve 40 may include various valve means that can selectively switch the flow path of the first coolant to the first radiator 60 or the fuel cell stack 10. For example, the second valve 40 may be a three-way valve. In the case of a three-way valve, the second valve 40 is connected to the first port 41 connected to the second connection line 140, and the first cooling line 110 so that the first coolant passing through the first radiator 60 flows in. ) and a second port 42 connected to the first coolant, and a third port 43 connected to the first cooling line 110 so that the first coolant flows into the first pump 30. By opening and closing the first port 41 or the second port 42 of the second valve 40, the flow path of the first coolant can be switched to the first radiator 60 or the fuel cell stack 10. Depending on the opening amount of the second valve 40, part of the first coolant may pass through the first radiator 60 and the remaining part may flow along the second connection line 140.

Although not shown in FIG. 1, the fuel cell system may be equipped with an ion filter (not shown) that filters ions in the first coolant. The ion filter may be placed on a first cooling line through which the first coolant flows, or may be placed on a separate connection line connected to the first cooling line. If the electrical conductivity of the first coolant increases due to corrosion or exudation of the system, electricity flows into the first coolant, causing a problem in which the fuel cell stack 10 is short-circuited or current flows toward the first coolant. , the first coolant must be able to maintain low electrical conductivity. The ion filter may be set to remove ions contained in the first coolant so that the electrical conductivity of the first coolant can be maintained below a certain level.

The second 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 second connection line 140 is connected to the first cooling line 110 between the first pump 30 and the first radiator 60, and the other end of the second 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.

The first radiator 60 may be set to cool the first coolant. The first radiator 60 may be formed in various structures capable of cooling the first coolant, and the present invention is not limited or limited by the type and structure of the first radiator 60. The first radiator 60 may be connected to the first reservoir 62 where the first coolant is stored.

The fuel cell system includes a first temperature sensor 112 that measures the temperature of the first coolant between the fuel cell stack 10 and the first point (the first valve 20), and another sensor of the first connection line 130. It includes a second temperature sensor 114 that measures the temperature of the first coolant between one end and the first pump 30, and a third temperature sensor 116 that measures the temperature of the first coolant in the heater 50. can do. The fuel cell system determines the inflow rate of the first coolant flowing into the fuel cell stack 10 based on the temperature measured by the first temperature sensor 112, the second temperature sensor 114, and the third temperature sensor 116. can be controlled. For example, if the measured temperature of the first coolant circulating along the first cooling line 110 is lower than a preset target temperature, the inflow rate of the first coolant may be controlled to be lower than the preset set flow rate.

The second cooling line 120 is configured to pass through the vehicle's electrical components 200, and the second coolant can circulate along the second cooling line 120. Here, the electrical components 200 of the vehicle can be understood as components that use the vehicle's power source as an energy source, and the present invention is not limited or limited by the type and number of the electrical components 200.

For example, a bi-directional high voltage DC-DC converter (BHDC) 210 provided between the fuel cell stack 10 and the vehicle's high voltage battery (not shown), and external air for driving the fuel cell stack 10. BPCU (blower pump control unit) 220, which controls the supply blower (not shown), LDC (low-voltage DC-DC converter) 230, which converts the high DC voltage supplied from the high-voltage battery into low DC voltage, fuel cell It may include at least one of an air compressor (ACP) 240 that compresses the air supplied to the stack 10, and an air cooler 250. Although not shown in FIGS. 1 to 3, the electrical component 200 may further include a DC-DC buck/boost converter.

A second pump 205 may be disposed on the second cooling line 120 to forcibly flow the second coolant. The second pump 205 may include a pumping means capable of pumping the second coolant, and the type and characteristics of the second pump 205 are not limited or limited.

A second radiator 70 may be disposed on the second cooling line 120 to cool the second coolant. The second radiator 70 may be formed in various structures capable of cooling the second coolant, and the type and structure of the second radiator 70 are not limited or limited. The second radiator 70 may be connected to the second reservoir 72 where the second coolant is stored.

In an embodiment, the first radiator 60 and the second radiator 70 may be configured to be cooled simultaneously by one cooling fan 80 as shown in FIG. 1. For example, the first radiator 60 and the second radiator 70 are arranged side by side, and the cooling fan 80 may be set to blow outside air to the first radiator 60 and the second radiator 70. . By allowing the first radiator 60 and the second radiator 70 to be cooled simultaneously by one cooling fan 80, the structure of the fuel cell system can be simplified and design freedom and space utilization can be improved. , power consumption for cooling the first radiator 60 and the second radiator 70 can be minimized.

In another embodiment, as shown in FIG. 2, the first cooling fan 80 for cooling the first radiator 60 and the second cooling fan 85 for cooling the second radiator 70 are arranged separately. It can be. In this case, the fuel cell system may exclude parameters related to the thermal load of the electrical component 200 when controlling the rotation speed of the first cooling fan 80. The embodiments described below are based on the fuel cell system structure of FIG. 1, but the same principles can be applied to the fuel cell system structure of FIG. 2.

Referring again to FIG. 1, the heat exchanger 300 may be set to exchange heat between the first coolant and the second coolant. When the heat exchanger 300 is included, the first cooling line 110 and the second cooling line 120 form a TMS (thermal management system) line through which the first coolant and the second coolant can flow while performing heat exchange. It can be configured, and in this case, the first coolant or the second coolant can be used as a coolant (cooling medium) or heat medium on the TMS line. For example, since the temperature of the second coolant that cools the electrical components is relatively lower than the temperature of the first coolant that cools the fuel cell stack 10, the fuel cell system exchanges heat between the first coolant and the second coolant. By doing so, the temperature of the first coolant can be lowered 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. Beneficial effects can be achieved by improving

In an embodiment, the heat exchanger 300 is 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 is connected to the heat exchanger ( The outlet of the second radiator 70 and the electrical components can be connected via 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 is exposed to the first coolant (e.g., the first coolant It may pass through the interior of the heat exchanger 300 to flow along the circumference of the second cooling line 120. In this way, the fuel cell system can lower the temperature of the first coolant flowing into the fuel cell stack 10 by mutual heat exchange between the first coolant and the second coolant. The first temperature of the first coolant passing through the first radiator 60 is higher than the second temperature of the second coolant passing through the second radiator 70, and the first temperature of the first coolant passing through the heat exchanger 300 is higher than the second temperature of the second coolant passing through the heat exchanger 300. The third temperature may be formed lower than the first temperature. As an example, the first temperature of the first coolant may be approximately 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 exchanged with the second coolant) may be formed to be 1°C lower than the first temperature.

The heat exchanger 300 according to FIGS. 1 and 2 is disposed separately from the first radiator 60, but in another embodiment, the heat exchanger 300 may be directly connected to the first radiator 60 as shown in FIG. 3. there is. For example, the heat exchanger 300 may be connected to a designated location (upper left portion) of the first radiator 60, but is not limited thereto.

FIG. 4 is a diagram showing a heating structure of a fuel cell system according to an embodiment of the present invention, and FIG. 5 is a diagram showing a control block diagram of a fuel cell system according to an embodiment of the present invention.

Referring to FIG. 4, the heating structure of the fuel cell system is to pump the air (heated air) discharged from the radiators 60 and 70 into the duct 420 through a blower and supply it to the interior of the vehicle, thereby recovering the coolant from the coolant. Use waste heat to heat the vehicle's interior.

For example, the first radiator 60 cools the first coolant discharged from the fuel cell stack 10 and then sends it back to the fuel cell stack 10. At this time, the cooling fan 80 blows outside air to the first radiator 60, and the first radiator 60 recovers waste heat from the first coolant by the cooling fan 80 and cools it. Accordingly, the heating unit of the fuel cell system can supply air (heated air) discharged from the first radiator 60 to the room through the duct 420. As shown in FIG. 2, the first radiator 60 and the second radiator 70 are arranged side by side, and the first radiator 60 and the second radiator 70 are simultaneously operated by one cooling fan 80. When cooled, the heating unit of the fuel cell system may supply air (heated air) discharged from the first radiator 60 and the second radiator 70 to the room through the duct 420. However, in the following description, for convenience, it will be referred to as a radiator 60.

The cooling fan 80 may be configured as a multi-blade blower fan (or may be referred to as a 'sirocco fan'). In this way, since the multi-blade type blower fan can be miniaturized, a small cooling fan 80 can be installed, thereby reducing the overall size of the fuel cell system, and can be used in a small fuel cell system.

Additionally, the cooling fan 80 may replace the blower of the heating unit and serve to pump air (heated air) discharged by the radiator 60 after cooling the radiator 60 to the heating unit of the vehicle. At this time, the air suction direction of the cooling fan 80 may be controlled in the opposite direction by the control unit 510 shown in FIG. 5.

The heating unit of the fuel cell system may include a PTC heater 410, a blower, a duct 420, a damper door 431, 435, and an actuator 440.

The PTC heater 410 is a heat source that generates heat as it operates by receiving electrical energy from the battery or fuel cell stack 10 mounted on the vehicle, and heats the air supplied to the interior of the vehicle through the duct 420. It plays a role. The operation of the PTC heater 410 may be controlled by the control unit 510 shown in FIG. 5.

The blower can be replaced with a cooling fan 80 that cools the radiator 60. Accordingly, the cooling fan 80 transports the air (heated air) discharged by the radiator 60 into the duct 420 and discharges it along the duct 420 to the inside or outside of the vehicle. Here, the air discharged by the radiator 60 is air heated by waste heat recovered from the coolant, and by supplying this heated air to the interior of the vehicle, interior heating is possible without operating the PTC heater 410. Indoor heating efficiency can be increased by reducing the power usage of the PTC heater 410.

The duct 420 is a conveying passage for supplying heated air transported by the cooling fan 80 into the room. Damper doors 431 and 435 and an actuator 440 may be installed on the flow path of the duct 420. The damper doors 431 and 435 and the actuator 440 serve to switch the flow path so that the air transported through the duct 420 can be selectively discharged to either the interior or exterior of the vehicle. Here, the damper doors 431 and 435 rotate by the actuator 440 (eg, an electric motor) to selectively open and close the indoor and outdoor flow paths of the duct 420. The damper doors 431 and 435 may include a first damper door 431 installed in the indoor flow path within the duct 420 and a second damper door 435 installed in the outdoor flow path. In this case, the actuator 440 may close the second damper door 435 when the first damper door 431 is opened and close the first damper door 431 when the second damper door 435 is opened. The actuator 440 operates under the control of the control unit 510 shown in FIG. 5 to control the positions of the damper doors 431 and 435.

When the indoor flow path of the duct 420 is opened by the first damper door 431 and the actuator 440, the air transported into the duct 420 by the cooling fan 80 may be supplied to the interior of the vehicle. . At this time, the PTC heater 410 may be placed on the outlet side of the duct 420.

Accordingly, the air discharged by the radiator 60 may be transported into the duct 420 by the cooling fan 80 and then passed through the PTC heater 410 to be supplied to the interior of the vehicle. If the PTC heater 410 does not operate, the air discharged by the radiator 60 flows into the duct 420 through the cooling fan 80 and flows into the interior of the vehicle along the interior flow path of the duct 420. can be supplied. As such, the fuel cell system according to the present invention can increase heating efficiency while minimizing power consumption by heating the interior of the vehicle only with air (heated air) discharged by the radiator 60.

Meanwhile, when the PTC heater 410 operates, the air discharged by the radiator 60 flows into the duct 420 through the cooling fan 80 and is transported along the indoor flow path by the PTC heater 410. It can be further heated and then supplied to the interior of the vehicle.

Referring to FIG. 5 , the fuel cell system may include a control unit 510, a first temperature sensor 520, and a second temperature sensor 530. Here, the first temperature sensor 520 may be a sensor placed inside the vehicle to measure the indoor temperature. Additionally, the second temperature sensor 530 may be a sensor disposed at the air outlet of the radiator 60 to measure the temperature of the air discharged from the radiator 60.

The control unit 510 may be a hardware device such as a processor or central processing unit (CPU), or a program implemented by a processor. The control unit 510 is connected to each component of the fuel cell system and can perform the overall function of the fuel cell system. As an example, the control unit 510 may be a fuel cell control unit (FCU) that controls overall functions of the fuel cell system.

The control unit 510 may control the cooling fan 80 to operate as a blower when the indoor heating mode is turned on. For example, the control unit 510 may control the air suction direction of the cooling fan 80 when the indoor heating mode is turned on.

In addition, when the discharge air of the radiator 60 is sucked into the duct 420 through the cooling fan 80, the control unit 510 detects the indoor temperature of the vehicle through the first temperature sensor 520 and detects the interior temperature of the vehicle through the second temperature sensor 520. The discharge air temperature of the radiator 60 can be detected through the sensor 530. Accordingly, the control unit 510 adjusts the angle of the actuator 440 based on the temperature detected by the first temperature sensor 520 and the second temperature sensor 530, or changes the operating state of the PTC heater 410. You can control it.

For example, if the indoor temperature detected by the first temperature sensor 520 is above the target temperature, the controller 510 may operate in standby mode without performing indoor heating control.

Meanwhile, the control unit 510 detects that the indoor temperature detected by the first temperature sensor 520 is below the target temperature and the discharge air temperature of the radiator 60 detected by the second temperature sensor 530 exceeds the indoor temperature. In this case, indoor heating control can be performed using only the discharged air from the radiator 60 without operating the PTC heater 410. At this time, the control unit 510 may adjust the angle of the actuator 440 coupled with the first damper door 431 to control the amount of wind flowing into the interior of the vehicle.

As an example, when the discharge air temperature of the radiator 60 exceeds the indoor temperature but the indoor temperature is less than a predetermined temperature, the control unit 510 operates the actuator ( By adjusting the angle of 440), the amount of air flowing into the room can be increased. As another example, when the discharge air temperature of the radiator 60 exceeds the indoor temperature but the indoor temperature is higher than a predetermined temperature, the control unit 510 operates the actuator 440 in the direction in which the first damper door 431 on the indoor flow path is closed. ) By variably adjusting the angle, the amount of air flowing into the room can be reduced or the current amount of air can be maintained.

In this way, the control unit 510 adjusts the angle of the actuator 440 coupled with the first damper door 431 on the indoor flow passage according to the indoor temperature in a state where the discharge air temperature of the radiator 60 exceeds the indoor temperature. You can control the indoor temperature.

Meanwhile, if the temperature of the discharge air from the radiator 60 is below the room temperature, the control unit 510 may determine that the temperature of the discharge air from the radiator 60 is insufficient to heat the room. Accordingly, when the discharge air temperature of the radiator 60 is below the room temperature, the control unit 510 supplies electrical energy from the battery or fuel cell stack 10 to the PTC heater 410 to variably operate the PTC heater 410. Therefore, the PTC heater 410 generates heat and heats the air supplied into the room through the PTC heater 410, thereby heating the room.

When operating the PTC heater 410, the control unit 510 determines the discharge air temperature of the radiator 60 through the second temperature sensor 530 after a delay for a predetermined time (e.g., the time during which the PTC heater 410 is preheated). sense At this time, the control unit 510 continues to variably operate the PTC heater 410 until the discharge air temperature of the radiator 60 exceeds the room temperature. If the discharge air temperature of the radiator 60 exceeds the indoor temperature, the control unit 510 may perform indoor heating control by stopping the operation of the PTC heater 410 and adjusting the angle of the actuator 440.

The heating control operation flow of the fuel cell system according to the present invention configured as described above will be described in more detail as follows.

FIG. 6 is a diagram illustrating the operation flow of a heating control method of a fuel cell system according to an embodiment of the present invention.

Referring to FIG. 6, when the indoor heating mode is turned on (S110), the fuel cell system measures the indoor temperature (T _cabin ) and compares it with the target temperature (T _target ). At this time, if the indoor temperature (T _cabin ) is higher than the target temperature (T _target ) (S120), the fuel cell system enters standby mode without performing indoor heating control (S125).

Afterwards, when the indoor temperature (T _cabin ) falls below the target temperature (T _target ) (S120), the fuel cell system measures the discharge air temperature (T _{RAD air out} ) of the radiator 60 to determine the indoor temperature (T _cabin ) and Compare, and as a result of the comparison, if the discharge air temperature (T _{RAD air out} ) of the radiator (60) exceeds the indoor temperature (T _cabin ) (S130), the first damper door (431) is opened without operating the PTC heater (410). Adjust the angle of the actuator 440 coupled (S140). In the 'S140' process, the actuator 440 can open the first damper door 431 on the indoor flow path in the duct 420 through a rotation motion, so the fuel cell system variably adjusts the angle of the actuator 440. By doing this, you can control the amount of air supplied indoors.

If the indoor temperature (T _cabin ) is above a preset temperature (e.g., A°C) (S150), the fuel cell system continues to repeat the 'S140' operation until indoor heating is stopped.

Meanwhile, if the indoor temperature (T _cabin ) is below a preset temperature (S150), the fuel cell system measures the discharge air temperature (T _{RAD air out} ) of the radiator 60 again to determine whether it exceeds the indoor temperature (T _cabin ). Confirm. If the discharge air temperature (T _{RAD air out} ) of the radiator (60) still exceeds the indoor temperature (T _cabin ), the fuel cell system closes the first damper door on the indoor flow path in the duct (420) in the 'S140' process. The angle of the actuator 440 can be adjusted so that 431 is opened more.

When the indoor temperature (T _cabin ) is below a preset temperature (S150), the fuel cell system measures the discharge air temperature (T _{RAD air out} ) of the radiator 60 again and confirms that it is below the indoor temperature (T _cabin ) ( S130), the PTC heater 410 is operated variably (S132). The PTC heater 410 operated in the 'S132' process generates heat and heats the air supplied to the interior of the vehicle through the interior flow path in the duct 420. Accordingly, the air heated by the PTC heater 410 is supplied to the interior of the vehicle, thereby increasing the interior temperature (T _cabin ).

When air heated by the PTC heater 410 is supplied indoors, the fuel cell system can similarly adjust the angle of the actuator 440 to control the volume of air supplied indoors (S140). However, since preheating time is required for the PTC heater 410 to reach a predetermined temperature, the fuel cell system can adjust the angle of the actuator 440 after a predetermined time delay (S134, S140).

Afterwards, the fuel cell system repeatedly performs the 'S120' to 'S150' processes to control the vehicle's interior heating. If there is a request to stop indoor heating (S160), the fuel cell system stops indoor heating and switches the indoor heating mode to OFF (S170).

As such, the fuel cell system according to the present invention minimizes the power consumption of the PTC heater 410 and increases fuel efficiency by using the waste heat of the coolant used to cool the fuel cell stack 10 in the fuel cell system for indoor heating. In addition, by using the cooling fan 80 of the radiator 60 as a blower for the heating unit, it is possible to secure space and reduce costs by removing parts such as HVAC blowers and heater cores (HTR CORE), and by reducing the cooling water path. By minimizing the cooling water pump efficiency, it is possible to increase the efficiency of the coolant pump. In addition, the fuel cell system according to the present invention can reduce the overall size of the fuel cell system by configuring the cooling fan 80 as a multi-blade blower fan, and therefore can be applied and utilized to small fuel cell systems.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications and variations will be possible to those skilled in the art without departing from the essential characteristics of the present invention.

Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

10: Fuel cell stack 60: First radiator
70: second radiator 80: cooling fan
410: PTC heater 420: duct
431, 435: Damper door 440: Actuator
510: Control unit 520: First temperature sensor
530: Second temperature sensor

Claims (18)

A cooling fan that sucks heated air discharged from the radiator and transfers it to an indoor heating duct;
an actuator that rotates a damper door on the flow path so that air introduced into the duct is discharged indoors; and
a control unit that controls the rotation angle of the actuator based on the temperature of the discharge air of the radiator;
A fuel cell system including. In claim 1,
A first temperature sensor that measures indoor temperature; and
The fuel cell system further includes a second temperature sensor that measures the temperature of the discharge air from the radiator. In claim 2,
The control unit,
During indoor heating, when the indoor temperature is below the target temperature and the discharge air temperature of the radiator exceeds the indoor temperature, the rotation angle of the actuator is adjusted to control the volume of air discharged into the room. fuel cell system. In claim 3,
The control unit,
A fuel cell system, characterized in that when the indoor temperature falls below a predetermined temperature during indoor heating, the rotation angle of the actuator is adjusted in a direction in which the damper door on the flow path is opened. In claim 2,
The control unit,
A fuel cell system that controls power supply to the PTC heater when the indoor temperature is below the target temperature and the discharge air temperature of the radiator is below the indoor temperature during indoor heating. In claim 5,
The PTC heater is,
A fuel cell system disposed at the outlet of the duct to heat air discharged into the room along the passage when power is supplied. In claim 5,
The control unit,
A fuel cell system, characterized in that when the discharge air temperature of the radiator exceeds the room temperature, power supply to the PTC heater is cut off. In claim 2,
The control unit,
A fuel cell system characterized in that it is controlled to operate in standby mode when the indoor temperature exceeds the target temperature during indoor heating. In claim 1,
The cooling fan is,
A fuel cell system characterized by consisting of a multi-blade blower fan. In claim 1,
The cooling fan is,
Outside air is blown to the radiator disposed on the cooling line through which coolant circulating through the fuel cell stack is circulated,
A fuel cell system characterized in that the heated air discharged from the radiator is sucked in during indoor heating and transferred to the duct. Inhaling heated air discharged from the radiator by a cooling fan and transferring it to an indoor heating duct;
Controlling an actuator that rotates a damper door on the flow path to discharge air introduced into the duct into the room; and
controlling the rotation angle of the actuator based on the discharge air temperature of the radiator;
A heating control method for a fuel cell system including. In claim 11,
Measuring indoor temperature from a first temperature sensor; and
A heating control method for a fuel cell system, further comprising measuring the discharge air temperature of the radiator from a second temperature sensor. In claim 12,
The step of controlling the rotation angle of the actuator is,
During indoor heating, when the indoor temperature is below the target temperature and the discharge air temperature of the radiator exceeds the indoor temperature, controlling the volume of air discharged into the room by adjusting the rotation angle of the actuator. A heating control method for a fuel cell system, characterized in that. In claim 13,
The step of controlling the rotation angle of the actuator is,
A heating control method for a fuel cell system, further comprising adjusting a rotation angle of the actuator in a direction in which the damper door on the flow path is opened when the indoor temperature falls below a predetermined temperature during indoor heating. In claim 12,
Controlling power supply to the PTC heater when the indoor temperature is below the target temperature and the discharge air temperature of the radiator is below the indoor temperature during indoor heating; and
A heating control method for a fuel cell system, further comprising the step of allowing the PTC heater to heat air discharged into the room along the flow path. In claim 15,
A heating control method for a fuel cell system, further comprising cutting off power supply to the PTC heater when the discharge air temperature of the radiator exceeds the room temperature. In claim 12,
A heating control method for a fuel cell system, further comprising operating in standby mode when the indoor temperature exceeds the target temperature during indoor heating. In claim 11,
It further includes the step of the cooling fan blowing outside air to the radiator disposed on a cooling line through which coolant circulating through the fuel cell stack,
A heating control method for a fuel cell system, characterized in that heated air discharged from the radiator is sucked in during indoor heating and transferred to the duct.

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