JP7347981B2 - fuel cell device - Google Patents

Description

The present disclosure relates to a fuel cell device.

A fuel cell generates electricity using raw fuel gas containing hydrogen and oxygen-containing gas (air), and supplies the electricity to the outside. Further, the fuel cell constitutes a part of a cogeneration system that recovers exhaust heat generated by the heat module of the fuel cell, stores it in a tank as hot water, and supplies this hot water directly or indirectly to the outside. Note that the entire system is called a fuel cell device.

A thermal circulation system using water as a heat medium is used to recover heat and store hot water (also called heat storage). The thermal circulation system includes a heat exchanger that exchanges heat with waste heat and water, a heat storage tank that stores hot water, and a circulation flow path and a circulation pump that circulate water between them.

Further, the thermal circulation system includes a radiator (cooler) for lowering the temperature of water fed to the heat exchanger, and a cooling fan that blows air to the radiator. This radiator lowers the temperature of the heat medium circulating in the heat exchanger and efficiently converts condensed water, which is the condensation of moisture in the exhaust gas, into reformed water for steam reforming, which is used in so-called "water independent operation." Recover the target.

Regarding the above-mentioned control of the cooling fan that blows air to the radiator arranged in the thermal circulation system, Patent Document 1 discloses that the on/off duty ratio of the rotational drive (motor) that adjusts the rotation of the radiator cooling fan is set to a predetermined value. It is disclosed that the temperature of the circulating heat medium can be more finely controlled and maintained within a certain range by performing multi-stage control at intervals of .

JP2019-96484A

By the way, fuel cell devices operate in two modes: normal operation, in which they generate power while connected to the grid power supply, and autonomous operation, in which they generate power by themselves when disconnected from the grid power supply, such as during a power outage. ). During this self-sustaining operation, the system continues to operate at the maximum rated power generation so that it can immediately follow changes in external load demands.

In addition, during the above-mentioned self-sustaining operation (rated operation), the fuel cell device generates surplus power to internally consume the maximum rated power generation (current) in case the external required load is small or disappears. Equipped with surplus power consumption components such as heaters.

However, because the surplus power consuming components are arranged so as to transfer the heat generated by the surplus power to the heat medium (water) circulating in the aforementioned thermal circulation system, during self-sustaining operation, compared to normal operation, The thermal circulation system was likely to reach high temperatures, and there was a risk of water bumping.

An object of the present disclosure is to provide a fuel cell device that can suppress deterioration in durability of a thermal circulation system.

The fuel cell device of the present disclosure is a fuel cell device that can perform normal operation control that is connected to a grid power source and autonomous operation control that disconnects from the grid power source and generates power independently. This fuel cell device includes a fuel cell module , a heat exchanger that exchanges heat between waste heat of the fuel cell module and a heat medium, and a circulation system that circulates the heat medium between the heat exchanger and a tank. a flow path, a surplus power consuming member disposed in the circulation flow path and energized when executing the self-sustaining operation control, a radiator disposed upstream of the heat exchanger in the circulation flow path, and the radiator. and a control device.
The control device performs cooling fan drive control that includes a first fan drive control that is executed during normal operation, and a second fan drive control that is executed during self-sustaining operation and that has a different drive pattern from the first fan drive control. Be prepared.

According to the fuel cell device of the present disclosure, deterioration in the durability of the thermal circulation system can be suppressed.

1 is a schematic configuration diagram of a fuel cell device according to an embodiment. FIG. 2 is a perspective view showing the configuration of the fuel cell device inside the outer case. It is a flowchart regarding first fan drive control. It is a flowchart regarding 2nd fan drive control. It is a flowchart regarding 2nd fan drive control.

Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 is a block diagram schematically showing the configuration of a fuel cell device according to an embodiment. Note that some of the general-purpose devices and equipment in the fuel cell device are not explained in detail, but are only given symbols in the drawings.

A fuel cell device 100 according to the embodiment shown in FIG. The system includes a heat storage tank 3 that collects water by heat exchange and stores it as hot water, and a reformed water tank 10 that stores condensed water generated by condensing water contained in exhaust gas as reformed water.

Further, the fuel cell device 100 includes a raw fuel supply device 13 including a raw fuel pump, a raw fuel flow path, etc., and an oxygen-containing gas supply device 14 including an air blower, an oxygen-containing gas flow path, etc. Furthermore, it includes a reformed water supply device including a condensed water flow path C, the above-mentioned reformed water tank 10, a reformed water supply pump P2, and a reformed water flow path R for continuing water self-sustaining operation.

The fuel cell device 100 includes the heat exchanger 2, the heat storage tank 3, the radiator 4, the cooling fan 5 that cools the radiator 4, the heat medium circulation pump P1, and the heat medium circulation flow that connects these in an annular manner. A heat medium circulation system (first heat cycle) for recovering exhaust heat is provided.

In addition, in FIG. 1, the heat medium (water) flow path from the bottom outlet (outlet) of the heat storage tank 3 to the inlet side of the radiator 4 is described as a flow path Q1 on the upstream side of the radiator 4. A heat medium flow path from the outlet side of the heat exchanger 2 to the upper inlet (inlet) of the heat storage tank 3 is described as a flow path Q2 on the downstream side of the radiator 4. A surplus power consumption member (surplus power heater) 6 used for consuming surplus power during self-sustaining operation of the fuel cell is disposed in the flow path Q2 on the downstream side.

The fuel cell device 100 is arranged in a case 40 made up of frames 41 and exterior panels 42, as shown in FIG. Inside the case 40, around the fuel cell module 1 and each auxiliary equipment, flow paths, piping, etc., there are the following control means 20, power adjustment device (power conditioner 30), and a plurality of measuring instruments. , sensors, or other auxiliary equipment.

The fuel cell device 100 includes a power conditioner 30 that is connected or interconnected with an external system power source and an external load, and a power conditioner 30 that is connected to the power conditioner 30 as a means for controlling the operation of the fuel cell module 1 and each auxiliary device. The system also includes a control device 20 that controls the operation of each auxiliary device that assists the power generation operation of the fuel cell, and a storage device attached to or built in this control device 20.

The control device 20 is connected to a storage device, a display device (both not shown), various components and various sensors that constitute the fuel cell device 100, and controls the entire fuel cell device 100, including each of these functional parts. Control and manage. The control device 20 obtains a program stored in an attached storage device (not shown) and executes this program to implement various functions related to each part of the fuel cell device 100.

Note that the fuel cell device 100 includes a plurality of temperature measuring devices or thermometers such as temperature sensors and thermistors for measuring the temperature of each part inside and outside the casing.

For example, as shown in FIG. 1, in the radiator flow path Q1 (hereinafter sometimes referred to as the upstream side) between the outlet at the lower part (bottom) of the heat storage tank 3 and the radiator 4, there is a channel Q1 on the radiator inlet side. A thermistor TM1 is arranged as a first temperature sensor that detects the temperature of the first heat medium. Note that the thermistor TM11 disposed at a low position (lower part) near the bottom of the heat storage tank 3 may be used as the first temperature sensor. This thermistor TM11 also detects the temperature of the first heat medium on the radiator inlet side.

In addition, in order to measure and confirm the temperature of water on the outlet side of the radiator 4 and the inlet side of the heat exchanger 2, a flow path Q2 (hereinafter referred to as downstream side) between the radiator 4 and the heat exchanger is used. ), the thermistor TM2 is disposed. This thermistor TM2 is an example of a second temperature sensor of the present disclosure that detects the temperature of the second heat medium on the radiator outlet side. Note that the thermistor TM12 disposed at the inlet of the heat exchanger 2 may be used as the second temperature sensor. This thermistor TM12 also detects the temperature of the second heat medium on the radiator outlet side.

Furthermore, in order to measure the temperature around the device (case), a thermistor TM3 for measuring outside temperature is provided.

In the embodiments described later, the first heat medium temperature (variable) measured by the thermistor TM1 or TM11 on the upstream side of the radiator, which is the first temperature sensor, is indicated as TH1, and the temperature on the downstream side of the radiator, which is the second temperature sensor, is expressed as TH1. The second heat medium temperature (variable) measured by the thermistor TM2 or TM12 on the side is written as TH2. In addition, the outside temperature (variable) measured by the thermistor TM3, which is the third temperature sensor, will be indicated as TH3 later.

In order to measure and confirm the temperature of the high temperature water led out from the outlet side of the heat exchanger 2, a thermistor TM4 is separately installed on the outlet side (upper side in the figure) of the heat exchanger 2 in the downstream circulation flow path Q2. May be placed.

When transmitting control signals or various information from the control device 20 described above to other functional units or devices, the control device 20, power conditioner 30, and other functional units may be connected by wire or wirelessly. Bye. In each figure, illustration of connection lines connecting the control device 20 and each device and each sensor that constitute the fuel cell may be omitted. Moreover, the control characteristic of this embodiment performed by the control device 20 will be explained later.

In the embodiment described later, the circulation pump P1 and the cooling fan 5 disposed in the heat medium circulation system (heat cycle) are both driven by a pulse drive system, and the control device 20 By increasing or decreasing the on/off duty ratio of the pulse drive, the rotational driving force and discharge amount of the circulation pump P1 and the rotational driving force and air blowing amount of the cooling fan 5 are adjusted to reduce the heat flowing in the heat medium circulation channel Q. Assume that the temperature of the medium (water) is controlled.

Further, in the embodiment, the cooling fan 5 of the radiator 4 includes a rotation sensor unit that measures and outputs the number of revolutions per hour of the fan, and a signal output from this rotation sensor unit is input to the control device 20. shall be taken as a thing. That is, the rotation speed (rotations/minute) of the fan described above replaces the amount of air blown by the cooling fan 5, which is not equipped with a flow meter or the like.

The control device 20 controls the power generation operation of the fuel cell 11 by appropriately switching between a plurality of operation modes. The plurality of operation modes include normal operation (normal operation control) and self-sustaining operation (self-sustaining operation control).

In normal operation, power generation of the fuel cell 11 is controlled while connected to the grid power source. In this embodiment, during normal operation, the control device 20 controls the cooling fan 5 using first fan drive control so as to lower the temperature of the heat medium supplied to the heat exchanger 2 and recover condensed water. . Note that the normal operation may include a rated operation in which the device is operated with the rated generated power, and a partial load operation in which the output is varied in accordance with fluctuations in the external load.

In the self-sustaining operation, even if the fuel cell 11 is disconnected from the grid power supply due to a power outage or the like, the fuel cell 11 is controlled to continue generating power, and the power is generated at the rated power generation amount. In addition, in order to maintain the rated power generation during self-sustaining operation, a surplus power heater 6 is provided in the thermal circulation system, and when the external required load is small or absent, the surplus power heater 6 is energized as an internal load. be done. In other words, it is controlled so that the sum of the internal load and external load corresponds to the rated power generation amount.

Here, the surplus power heater 6 is arranged so as to transfer the heat generated by the surplus power heater 6 to the heat medium circulating within the thermal circulation system. Therefore, during self-sustaining operation, the thermal circulation system tends to reach a higher temperature than during normal operation. Therefore, in this embodiment, the control device 20 controls the cooling fan 5 using second fan drive control that has a different drive pattern from the first fan control so that the thermal circulation system can be sufficiently cooled.

In other words, even during standalone operation where the thermal circulation system tends to reach a relatively high temperature, the heat medium is efficiently cooled by controlling the drive (rotation speed) of the cooling fan 5 in a drive pattern different from that during normal operation. Therefore, it is possible to suppress a decrease in the durability of the thermal circulation system.

The aforementioned first fan drive control and second fan drive control will be explained using flowcharts.

When the fuel cell is connected to the grid power supply, that is, when the control device 20 is in “normal operation” and is connected to the grid power supply via the power adjustment device (30), the control device 20 operates as shown in FIG. As shown in the flowchart shown in FIG. Based on the heat medium temperature TH2 (°C) of Controls air flow. This is an example of the first fan drive control in the cooling fan drive control of the present disclosure.

When the fuel cell is in a normal operating state, as shown in FIG. It is checked whether the second heat medium temperature TH2 measured by the thermistor TM2 (on the low temperature side) exceeds a predetermined target upper limit temperature X1. Note that the drive duty ratio of the cooling fan 5 at the start of the control is 0%.

In [S1], if the second heat medium temperature TH2 exceeds the upper limit temperature X1 [YES], the control device 20 changes the on/off duty ratio of the rotational drive (motor) in [S2] to [S5]. , the preset R1 (%) is increased.

Specifically, in [S2], after confirming that the outside temperature TH3 (°C) measured by thermistor TM3 (third temperature sensor) is lower than the second heat medium temperature TH2 described above, in [S3] In the determination, if the drive duty ratio of the cooling fan 5 is less than 100%, that is, it is not in a full speed rotation state, the control device 20 increases the fan drive duty ratio by R1 to increase the air flow rate of the cooling fan 5. Note that the increasing fan drive duty ratio R1 (%) can be set as appropriate depending on the capacity of the cooling fan 5 and the like. R1 is a small value within the range of 10 to 20%, for example.

Further, the control device 20 controls [S1] to [S5] until the second heat medium temperature TH2 becomes equal to or lower than the upper limit temperature X1 or the drive duty ratio of the cooling fan 5 reaches 100% (full speed drive). ] Repeat the loop.

On the other hand, in [S1], if the second heat medium temperature TH2 is equal to or lower than the upper limit temperature X1 [NO], the control device 20 controls the on/off duty of the rotational drive (motor) in [S6] to [S9]. The ratio is decreased by a preset R2 (%).

Specifically, in [S6], it is checked whether the second heat medium temperature TH2 is below the lower limit temperature X2, and if it is below, the drive duty ratio of the fan is determined in [S7]. Confirm that it is greater than 0%, that is, the fan is not stopped. If it is confirmed that the cooling fan 5 is not in a stopped state, the duty ratio of the fan drive is decreased by R2, and the amount of air blown by the cooling fan 5 is decreased. Note that the duty ratio R2 of the fan drive to be decreased can be set as appropriate depending on the capacity of the cooling fan 5 and the like. R2 is a small value within the range of 10 to 20%, for example.

The control device 20 performs [S1] and [S6] to [S6] until the second heat medium temperature TH2 reaches the lower limit temperature X2 or more or the drive duty ratio of the cooling fan 5 reaches 0% (fan stopped state). Repeat the loop of [S9].

As described above, in this embodiment, during normal operation, the on/off duty ratio of the rotational drive of the cooling fan 5 is increased/decreased relatively gently. In other words, when increasing the number of rotations of the cooling fan 5, the amount of increase in the number of rotations per unit time is reduced, and similarly, when decreasing the number of rotations of the cooling fan 5, the number of rotations per unit time is decreased. The amount is reduced.

Thereby, the temperature of the circulating heat medium can be more precisely maintained within a certain range (X2≦TH2≦X1). Note that the upper limit temperature X1 and the lower limit temperature X2 may be appropriately set to temperatures at which sufficient condensed water can be recovered, based on the rated power generation amount of the fuel cell module 1 and the heat exchange efficiency of the heat exchanger 2.

When the fuel cell is disconnected from the grid power source and is operating independently, the control device 20 controls the thermistor TM1 (first temperature sensor) or thermistor TM11 disposed at the lower part of the heat storage tank 3 on the upstream side of the radiator 4 inlet, and the thermistor TM3 (third temperature sensor). ), the amount of air blown by the cooling fan 5 is controlled based on the outside temperature TH3 measured by the cooling fan 5. This is an example of second fan drive control in the cooling fan drive control of the present disclosure.

When the control [starts], the control device 20 checks in [S11] whether the first heat medium temperature TH1 on the inlet side of the radiator 4 has reached a temperature exceeding [outside temperature TH3+Y]°C. Note that the drive duty ratio of the cooling fan 5 at the start of the control is 0%.

In [S11], if the first heat medium temperature TH1 reaches a temperature exceeding [outside temperature TH3+Y]°C [YES], the control device 20 sets the fan drive duty ratio to R3 (in [S12]). %) to increase the amount of air blown by the cooling fan 5.

Note that the increase amount R3 (%) in the duty ratio of the fan drive only needs to be larger than the increase amount R1 (%) in the cooling fan in the first fan drive control, and can be set as appropriate depending on the capacity of the cooling fan 5 and the like. Further, Y° C. added to the outside air temperature TH3 is a small value within the range of 1 to 10° C., for example.

In addition, in [S11], if the first heat medium temperature TH1 on the inlet side of the radiator 4 is lower than [outside temperature TH3+Y]°C [NO], the first heat medium temperature TH1 is equal to or higher than [outside temperature TH3+Y]°C. Repeat the loop until .

In this embodiment, during self-sustaining operation, the on/off duty ratio of the rotational drive of the cooling fan 5 is increased more quickly than during normal operation. That is, when increasing the number of rotations of the cooling fan 5, the amount of increase (width of increase) in the number of rotations per unit time is increased.

That is, by increasing the amount of increase in the number of rotations per unit time, the temperature of the heat medium in the thermal circulation system can be lowered to a greater extent. As a result, even if the required power from the external load is reduced and the surplus power heater 6 disposed on the heat medium circulation path Q is activated, bumping of water occurs in the heat medium circulation path Q. can be suppressed.

In addition, in this embodiment, when increasing the rotation speed of the cooling fan 5 in the second fan drive control, the increase amount is set to R3 (%), but the increase amount R3 (%) is It only needs to be larger than the increase amount R1 (%) of the cooling fan in drive control.

Next, in [S13], with the duty ratio of the cooling fan 5 increased by R3, it is checked whether the first heat medium temperature TH1 on the inlet side of the radiator 4 is lower than the outside air temperature TH3.

When it is confirmed in [S13] that the first heat medium temperature TH1 has become lower than the outside temperature TH3 (°C) [YES], in [S14] the duty ratio of the fan drive is decreased by R4 (%). After reducing the amount of air blown by the cooling fan 5, the process returns to [S11].

Note that the reduction amount R4 (%) of the duty ratio of the fan drive only needs to be larger than the reduction amount R2 (%) of the cooling fan in the first fan drive control, and can be set as appropriate depending on the capacity of the cooling fan 5 and the like. Alternatively, the cooling fan 5 may be stopped by setting the reduction amount R4 to 100%.

On the other hand, in [S13], if the first heat medium temperature TH1 of the lower part of the heat storage tank 3 is [NO] higher than the outside temperature TH3, the loop is continued until the first heat medium temperature TH1 becomes lower than the outside temperature TH3. repeat.

In this embodiment, during self-sustaining operation, the on/off duty ratio of the rotational drive of the cooling fan 5 is quickly reduced compared to during normal operation. That is, when reducing the rotation speed of the cooling fan 5, the amount of decrease in the rotation speed per unit time is increased.

That is, by increasing the amount of decrease in the number of rotations per unit time, the power consumption of the cooling fan 5 can be suppressed and the internal load of the fuel cell device can be reduced, so more power can be supplied to the external load. can do.

In the present embodiment, in the first fan drive control executed during normal operation, condensed water is efficiently recovered by driving the cooling fan 5 based on the temperature TH2 of the second heat medium on the radiator outlet side. .

On the other hand, in the second fan drive control executed during standalone operation, where the temperature of the heat medium tends to be higher than during normal operation, the temperature of the first heat medium on the radiator inlet side, which is higher than the radiator outlet side, is By driving the cooling fan 5 based on TH1, the temperature of the heat medium in the thermal circulation system can be efficiently reduced. Furthermore, even when the surplus power heater 6 is activated, it is possible to suppress the occurrence of bumping of water within the heat medium circulation channel Q.

During execution of the second fan drive control, the first heat medium temperature TH1 measured by the thermistor TM1 on the inlet side of the radiator 4 or TM11 arranged in the heat storage tank 3, and the outside temperature TH3 measured by the thermistor TM3. By controlling the cooling fan 5 based on the heat medium temperature comparison control to be compared, the heat medium in the thermal circulation system can be appropriately cooled.

Furthermore, while the heating medium temperature comparison control is being executed, by controlling the cooling fan 5 on and off, the temperature of the heating medium in the thermal circulation system can be quickly lowered, and the internal load of the fuel cell device 100 can be reduced. , more power can be supplied to external loads.

By the way, the heating medium temperature comparison control controls the rotation speed of the cooling fan 5 based on the result of comparing the heating medium temperature of the thermal circulation system and the outside air temperature, so when the outside air temperature is low such as in winter, , the heat transfer medium may be cooled excessively.

Therefore, the control device 20 controls the second heat medium temperature TH2, which is measured by the thermistor TM2 (second temperature sensor) disposed at the radiator 4 outlet (heat exchanger 2 inlet), as a reference. It is determined whether the medium temperature TH2 satisfies the temperature at which the cooling fan 5 is forcibly stopped, and based on this determination, control for forcibly stopping the cooling fan 5 (freeze suppression control) is executed. The following is an example of freeze suppression control according to the present disclosure.

In the flowchart shown in FIG. 5, when the control starts, the control device 20 moves the thermistor TM2 disposed at the outlet of the radiator 4, which is also used in the first fan drive control during the normal operation described above, to the control device 20 in [S21]. Whether or not the second heat medium temperature TH2 measured by the second temperature sensor (second temperature sensor) is lower than the first set temperature Z1, which is the standard for starting the "freeze suppression mode" that forcibly stops the cooling fan 5. , check.

In [S21], if the second heat medium temperature TH2 is less than the first set temperature Z1 [YES], the second fan is not driven regardless of the first heat medium temperature TH1 or the outside air temperature TH3. Regardless of the driving state of the cooling fan 5 in the control, the cooling fan 5 is forcibly stopped in [S22].

In addition, in [S21], if the second heat medium temperature TH2 is higher than the first set temperature Z1 [NO], the loop is repeated until the second heat medium temperature TH2 becomes less than the first set temperature Z1. .

As a result, freezing damage to the water pipes that constitute the thermal circulation system within the fuel cell device 100 is suppressed, and therefore it is possible to suppress a decrease in the durability of the thermal circulation system.

Next, in [S23], it is confirmed whether or not the second heat medium temperature TH2 exceeds the second set temperature Z2 while the cooling fan 5 is forcibly stopped.

In [S23], if the second heat medium temperature TH2 is higher than the second set temperature Z2 [YES], the forced stop of the cooling fan 5 is canceled in [S24]. The drive duty ratio of the cooling fan 5 when the forced stop is canceled is determined based on the second fan drive control described above.

In addition, in [S23], if the second heat medium temperature TH2 is lower than the second set temperature Z2 [NO], the loop is repeated until the second heat medium temperature TH2 becomes higher than the second set temperature Z2. . Note that the second set temperature Z2 is higher than the first set temperature Z1.

Thereby, the heat medium can be efficiently cooled while suppressing freezing of the water pipes that constitute the thermal circulation system within the fuel cell device 100.

1 Fuel cell module 2 Heat exchanger 3 Heat storage tank 4 Radiator 5 Cooling fan 20 Control device 100 Fuel cell device P1 Circulation pump Q Heat medium circulation channel TM Thermistor

Claims (8)

A fuel cell device capable of performing normal operation control connected to a grid power supply and independent operation control disconnected from the grid power supply and generating power independently,
fuel cell module ;
a heat exchanger that exchanges heat between the exhaust heat of the fuel cell module and a heat medium;
a circulation flow path for circulating the heat medium between the heat exchanger and the tank;
a surplus power consuming member disposed in the circulation flow path and energized when executing the self-sustaining operation control;
a radiator disposed upstream of the heat exchanger in the circulation flow path;
a cooling fan that blows air to the radiator;
comprising a control device;
The control device includes:
First fan drive control executed during normal operation;
a second fan drive control that is executed during self-sustaining operation and has a different drive pattern from the first fan drive control;
A fuel cell device comprising a cooling fan drive control including: The fuel according to claim 1, wherein the cooling fan drive control is such that the amount of increase in the rotational speed of the cooling fan per unit time is set to be larger in the second fan drive control than in the first fan drive control. battery device. 3. The cooling fan drive control according to claim 1, wherein the amount of decrease in the number of rotations of the cooling fan per unit time is set to be larger in the second fan drive control than in the first fan drive control. fuel cell equipment. a first temperature sensor that detects the temperature of the heat medium on the radiator inlet side;
a second temperature sensor that detects the temperature of the heat medium on the radiator outlet side,
The control device includes:
controlling the rotation speed of the cooling fan in the first fan drive control based on the temperature detected by the second temperature sensor;
The fuel cell device according to any one of claims 1 to 3, wherein the rotation speed of the cooling fan in the second fan drive control is controlled based on the temperature detected by the first temperature sensor. further comprising a third temperature sensor that detects the temperature outside the device,
The control device includes:
A heating medium temperature comparison control that compares a first heating medium temperature measured by the first temperature sensor and an outside air temperature measured by the third temperature sensor,
5. The fuel cell device according to claim 4, wherein during execution of the second fan drive control, the number of rotations of the cooling fan is increased or decreased based on the heat medium temperature comparison control. The fuel cell device according to claim 5, wherein the control device controls on/off of the cooling fan based on the heat medium temperature comparison control. The control device executes freeze suppression control to stop driving the cooling fan when the second heat medium temperature measured by the second temperature sensor is lower than a predetermined first set temperature. , The fuel cell device according to any one of claims 4 to 6. When the second heat medium temperature measured by the second temperature sensor exceeds a predetermined second set temperature during execution of the freezing suppression control,
The fuel cell device according to claim 7, wherein the control device stops execution of the freeze suppression control and returns to the second fan drive control.