Air-cooled reactor control method

Abstract

The invention provides an air-cooled reactor control method. The temperature of the galvanic pile is monitored, the water content in the galvanic pile is tested by using the internal resistance tester, the voltage change condition of the galvanic pile is further combined, and the rotating speed and duty ratio of the fan are comprehensively analyzed and controlled, so that the purposes of saving energy and meeting temperature control are achieved, the supply of cathode air gas can be met, and the service life of the galvanic pile is prolonged. And water content removal is further controlled, so that the water content of the membrane is ensured, and stable and normal operation of the galvanic pile is ensured. Furthermore, by comprehensively analyzing the data, measuring the actual operation condition of the galvanic pile and the change of the operation condition, adjusting the rotating speed of the fan and controlling the operation power of the galvanic pile, the dynamic adjustment of different operation conditions is achieved, the stable operation of the galvanic pile is ensured, the auxiliary consumption of the fan is further reduced, and the service life of the fan is prolonged. And the power generation efficiency of the stack system is improved.

Description

Technical Field

[0001] This invention belongs to the field of fuel cells, specifically relating to a method for controlling an air-cooled reactor. Background Technology

[0002] Hydrogen fuel cells are gaining widespread attention due to their high conversion efficiency and pollution-free nature. Currently, they are being demonstrated in large-scale applications in the heavy-duty transportation sector, with promising results. Further promoting hydrogen fuel cells and developing their application in light-duty transportation scenarios such as drones and electric vehicles can effectively support their large-scale development. During operation, hydrogen fuel cells continuously generate heat, requiring internal heat dissipation to prevent thermal runaway and irreversible losses. Based on cooling methods, fuel cells can be divided into water-cooled and air-cooled stacks. Air-cooled stacks can be further divided into closed and open stacks. Air-cooled stacks utilize air for heat dissipation. As mentioned above, for use in light-duty transportation, air-cooled stacks are adopted to simplify the fuel cell system and reduce weight, eliminating the need for a water-cooling module. Open-type air-cooled stacks further eliminate the need for an air intake system, utilizing an external fan to simultaneously supply air to the cathode and dissipate heat from the stack. Because it's an open-type fuel cell stack, air humidification is impossible. However, the proton exchange membrane (PEM) in a fuel cell requires a humid environment to conduct protons. This means the moisture in the stack can only be supplied by the water produced by the reaction itself. Furthermore, airflow carries away some moisture, necessitating airflow control to ensure the water produced in the stack meets the PEM's operating requirements. Importantly, the heat released during the reaction raises the stack temperature. Since the saturated vapor pressure of water increases with temperature, the evaporation rate accelerates. This temperature rise leads to increased moisture loss through the air outlet, causing the membrane to dry out, potentially resulting in perforation or mechanical damage, and ultimately reducing the performance of the PEM and the fuel cell stack. In an open-type air-cooled stack, cooling heavily relies on airflow, which contradicts the stack's need for moisture retention. Therefore, airflow control is crucial to resolving this contradiction.

[0003] Current technologies calibrate under different fuel cell stack operating conditions, controlling fan speed to balance stack temperature and air supply. However, reducing stack operating power leads to decreased stack temperature and excessive fan auxiliary losses; increasing stack operating power may result in insufficient air supply or uncontrolled stack temperature. It is impossible to dynamically adjust fan speed under actual stack operating conditions to achieve a balance between airflow and heat dissipation, thereby effectively reducing fan auxiliary losses. Air-cooled fuel cell stacks, due to their reliance on fans for cooling and the compact design of fuel cell plates, struggle to guarantee adequate stack cooling. Especially in open-type air-cooled reactors, the fan also serves to supply cathode air, making temperature control even more challenging. It requires both controlling the reactor stack temperature and supplying the necessary reaction air to the cathode. The air metering ratio is affected by the reactor stack current and the number of cells, while the reactor stack temperature is influenced by the individual cell voltage and the number of cells. A potential problem arises: if the air metering ratio is too low, effective heat dissipation and temperature control are difficult; if it's too high, excessive heat dissipation leads to excessively low reactor stack reaction temperatures, preventing full performance. Therefore, it's essential to control the fan speed and adjust the amount and speed of the incoming gas to meet both the cathode gas supply and heat dissipation requirements, ensuring stable reactor stack operation. This invention describes a temperature control strategy for air-cooled reactors that monitors and adjusts the stack temperature, internal resistance, fan speed, and reactor stack voltage to ensure stable power output. Summary of the Invention

[0004] This invention provides a control method for an air-cooled fuel cell reactor. By monitoring the reactor stack temperature and testing the water content within the reactor stack using an internal resistance tester, and further combining this with voltage changes, the fan speed and duty cycle are comprehensively analyzed and controlled. This achieves energy saving while maintaining temperature control, ensuring the supply of cathode air, and controlling water removal to maintain membrane moisture content and ensure stable and normal operation of the reactor stack. Furthermore, by comprehensively analyzing the above data and measuring the actual operating conditions and changes in those conditions, the fan speed and reactor stack operating power can be adjusted to achieve dynamic regulation under different operating conditions, ensuring stable operation of the reactor stack, reducing fan auxiliary losses, and improving the power generation efficiency of the reactor stack system.

[0005] The technical solution of this invention is as follows.

[0006] This invention relates to an air-cooled reactor system comprising a main body and a measurement section. The main body includes the air-cooled reactor and an external fan. The measurement section includes a temperature measuring instrument, a voltmeter, an ammeter, and an internal resistance meter. The temperature measuring instrument has three probes, located at different parts of the reactor core, to monitor the temperature at different core locations, ensuring the reliability and uniformity of the measurements. The voltmeter and ammeter have two leads connected to the positive and negative terminals of the reactor current collector, respectively, to monitor changes in the reactor's voltage and current. The internal resistance meter has two leads connected to the positive and negative terminals of the reactor current collector, respectively, to monitor changes in the reactor's internal resistance, further monitoring changes in the internal water content. This invention provides an air-cooled reactor control strategy that, by monitoring voltage changes and combining them with internal resistance meter measurements, reflects the dryness state of the proton exchange membrane within the reactor. Simultaneously, it adjusts the fan speed based on temperature changes within the reactor, enabling stable reactor operation, reducing fan auxiliary losses, and achieving optimal system efficiency.

[0007] A method for controlling an air-cooled reactor reflects the dryness of the proton exchange membrane in the reactor by monitoring changes in the internal voltage and combining this with data from an internal resistance meter. Simultaneously, the method adjusts the fan speed based on temperature changes within the reactor, enabling stable operation of the reactor and reducing fan auxiliary losses to achieve optimal system efficiency.

[0008] The specific steps are as follows:

[0009] If an abnormal voltage drop occurs, first determine if the rate of voltage drop is greater than the first rate of voltage drop (1-5 mV / min). If not, continue to determine if the rate of internal resistance rise is greater than the first rate of internal resistance rise (1-5 mΩ / min). If not, further determine if the stack temperature is greater than 60℃. Since air-cooled stacks use open-cathode air cooling, the stack operating temperature is generally required not to exceed 60℃, otherwise thermal runaway may easily occur, causing irreversible effects. If the temperature is less than or equal to 60℃, it indicates that the internal state of the stack is relatively good. However, at this point, it is still impossible to determine whether the performance degradation is due to the stack temperature drop caused by membrane drying or excessive fan speed. Further determination of temperature changes is required. Check if the fuel cell stack temperature drops or stabilizes. If so, the fan speed is too high, and the fan speed needs to be reduced to the first step value. At the same time, monitor whether the fuel cell stack voltage stabilizes or rises. If so, it indicates that the fuel cell stack is operating normally and the fan has reached its optimal operating power, reducing the system's auxiliary power consumption. At this time, maintain the fan speed. If not, continue to reduce the fan speed and continue to judge the fuel cell stack voltage change until the fuel cell stack is operating stably. If the fan speed is reduced to the first step value (1000-2000 rpm) more than 3 times and the fuel cell stack voltage still does not stabilize or rise, it indicates that there is another problem with the fuel cell stack. At this time, perform the shutdown and inspection procedure.

[0010] If the fuel cell stack temperature rises during the process of determining whether the temperature has decreased or stabilized, then it is determined whether the temperature rise exceeds the first rate of temperature increase (1-3℃ / min). If not, it indicates that the temperature rise is relatively slow, and the increased moisture removal caused by the internal temperature rise is dominant, leading to the membrane slowly drying out. Therefore, the fan speed is increased to the first step value (1000-2000 rpm) to reduce the fuel cell stack temperature. The appropriateness and sufficiency of the fan speed are determined based on whether the voltage stabilizes or rises. If not, the fan speed is increased by the first step value (1000-2000 rpm) again, and the voltage change is further assessed until the fuel cell stack stabilizes. At this point, the fan speed is maintained. If the voltage has not stabilized or risen after increasing the fan speed by the first step value more than 3 times, it indicates that the increase in fan speed is far from sufficient. In this case, the fan speed is increased to the second step value (2000-2500 rpm), and the appropriateness and sufficiency of the fan speed are determined based on whether the voltage stabilizes or rises. No, continue increasing the fan speed to the second step value and continue to monitor the fuel cell voltage change until the fuel cell is running stably. Then, maintain the fan speed. If increasing the fan speed to the second step value more than 3 times and the fuel cell voltage still has not stabilized or increased, it means that the increase in fan speed is still far from sufficient. Increase the fan speed to the third step value (2500-3000 rpm) and determine whether the fan speed is appropriate and sufficient based on whether the voltage stabilizes or increases. If no, continue increasing the fan speed to the third step value and continue to monitor the fuel cell voltage change until the fuel cell is running stably. Then, maintain the fan speed. If increasing the fan speed to the third step value more than 3 times and the fuel cell voltage still has not stabilized or increased, adjust the fan to the maximum speed (3000-4000 rpm) and monitor whether the fuel cell voltage stabilizes or increases. If it stabilizes or increases, maintain the fan speed. If no, it means that the fuel cell temperature can no longer be controlled by adjusting the fan, thermal runaway has occurred inside the fuel cell, and an urgent shutdown and inspection is required.

[0011] If the voltage drop rate is greater than the first voltage drop rate, then determine if the voltage drop rate of the fuel cell stack is greater than the second voltage drop rate (5-10 mV / min). If yes, it indicates that the temperature is rising too quickly, and the fuel cell stack should be cooled rapidly by increasing the fan speed to the third step. Subsequent steps are as described above. If no, then determine if the internal resistance rise rate is greater than the second internal resistance rise rate. The rise rate of internal resistance determines the rate of water loss from the proton exchange membrane. If it is too fast, the membrane may dry out rapidly or even perforate. If yes, proceed directly to increasing the fan speed to the third step value and rapidly increasing the fan speed. Subsequent steps are as described above. If no, then determine if the fuel cell stack temperature is greater than 60°C. If yes, proceed directly to increasing the fan speed to the third step and rapidly increasing the fan speed. Subsequent steps are as described above. If no, determine if the fuel cell stack temperature rise rate is greater than the second temperature rise rate. (3-5℃ / min); If yes, proceed directly to the next step, increasing the fan speed by the third step to quickly increase the fan speed, and follow the steps above; if no, it indicates that the temperature rise is relatively slow, and the increase in internal temperature of the fuel cell leads to increased moisture removal, which plays a dominant role, causing the membrane to dry slowly. Therefore, increase the fan speed by the second step to reduce the fuel cell temperature. Determine whether the fan speed is appropriate and sufficient based on whether the voltage is stable or rising; if no, continue to increase the fan speed by the second step and continue to determine the change in fuel cell voltage until the fuel cell is running stably, then proceed to the operation of maintaining the fan speed; if the fuel cell voltage has not stabilized or risen after increasing the fan speed by the second step more than 3 times, it indicates that the increase in fan speed is far from sufficient; then proceed directly to the operation of increasing the fan speed by the third step to quickly increase the fan speed, and follow the steps above.

[0012] In the above method, the first voltage decrease rate is less than the second voltage increase rate; the first internal resistance increase rate is less than the second internal resistance increase rate; the first temperature increase rate is less than the second temperature increase rate; and the first fan speed step value is less than the second step value and the third step value.

[0013] Compared with the prior art, the advantages of the present invention are:

[0014] This invention monitors the fuel cell stack temperature and tests the water content within the stack using an internal resistance tester. Furthermore, by combining this with voltage variations, it comprehensively analyzes and controls the fan speed and duty cycle. This achieves energy savings while maintaining temperature control and ensuring adequate cathode air supply. It also controls water removal to maintain membrane moisture content and guarantee stable and normal operation of the fuel cell stack. Furthermore, by comprehensively analyzing the above data and measuring the actual operating conditions and changes in those conditions, the fan speed and operating power of the fuel cell stack can be adjusted. This achieves dynamic regulation under different operating conditions, ensuring stable operation of the fuel cell stack, reducing fan auxiliary losses, and improving the power generation efficiency of the fuel cell stack system. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the air-cooled reactor of the present invention;

[0016] Figure 2 This is a schematic diagram of a wind-cooled reactor control method according to the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0018] Example 1

[0019] like Figure 1 As shown, in this embodiment, the air-cooled reactor includes a main body and a measurement section. The main body includes an air-cooled reactor 1 and an external fan 2. The measurement section includes a temperature measuring instrument 3, a voltmeter / ammeter 4, and an internal resistance meter 5. The external fan 2 is located outside the air-cooled reactor 1. The two leads of the voltmeter / ammeter 4 are connected to the positive and negative terminals of the reactor current collector, respectively, to monitor the voltage and current changes of the reactor. The two leads of the internal resistance meter 5 are connected to the positive and negative terminals of the reactor current collector, respectively, to monitor the internal resistance changes of the reactor, and further monitor the changes in water content inside the reactor. The temperature measuring instrument 3 has three probes, located at different parts of the reactor core, to monitor the temperature at different locations in the reactor core, ensuring the reliability and uniformity of the measurement.

[0020] like Figure 2 As shown, this embodiment provides a method for controlling an air-cooled reactor, the steps of which are as follows:

[0021] If an abnormal voltage drop occurs (S01), first determine if the rate of voltage drop is greater than the first rate of voltage drop (S02). If not, continue to determine if the rate of internal resistance increase is greater than the first rate of internal resistance increase (S03). If not, further determine if the stack temperature is greater than 60℃ (S04). Because air-cooled stacks use open-cathode air cooling, the stack operating temperature is generally required not to exceed 60℃, otherwise thermal runaway may easily occur, causing irreversible effects. If the temperature is less than or equal to 60℃, it indicates that the internal state of the stack is relatively good. However, it is still impossible to determine whether the performance degradation is caused by the temperature drop due to membrane drying or excessive fan speed. Further determination of temperature changes is required. Check if the fuel cell stack temperature has decreased or stabilized (S05). If yes, it indicates that the fan speed is too high. In this case, the fan speed needs to be reduced to the first step value (S06). At the same time, monitor whether the fuel cell stack voltage is stable or rising (S07). If yes, it indicates that the fuel cell stack is operating normally and the fan has reached its optimal operating power, reducing the system's auxiliary power consumption. At this time, maintain the fan speed (S17). If not, continue to reduce the fan speed (S06) and continue to judge the change in fuel cell stack voltage until the fuel cell stack is operating stably. If the fan speed is reduced to the first step value more than 3 times and the fuel cell stack voltage still has not stabilized or risen, it indicates that there are other problems with the fuel cell stack. At this time, perform a shutdown inspection (S20).

[0022] Following the determination of whether the fuel cell stack temperature has decreased or stabilized (S05), if the fuel cell stack temperature rises during the determination of whether the temperature has decreased or stabilized, then it is determined whether the temperature rise is greater than the first temperature rise rate (S08). If not, it indicates that the temperature rise is relatively slow, and the moisture removal caused by the temperature rise inside the fuel cell stack is increased and plays a dominant role, causing the membrane to slowly dry out. Therefore, the fan speed is increased to the first step value (S09) to reduce the fuel cell stack temperature. The appropriateness and sufficiency of the fan speed are determined based on whether the voltage is stable or rising (S10). If not, the fan speed is increased to the first step value (S09) again, and the change in fuel cell stack voltage is further determined until the fuel cell stack is running stably. At this time, the operation of maintaining the fan speed (S17) is performed. If the first step value of the fan speed is increased more than 3 times and the fuel cell stack voltage has not stabilized or risen, it indicates that the increase in fan speed is far from sufficient. At this time, the fan speed is increased to the second step value (S15), and the appropriateness and sufficiency of the fan speed are determined based on whether the voltage is stable or rising (S16). If not, the fan speed is increased to the second step value. If the stack voltage remains unstable or does not rise after increasing the fan speed by more than three times (S15), the operation proceeds to S17. If the fan speed is increased to the second-level value more than three times, the stack voltage is still not stable or rising, indicating that the increase in fan speed is still far from sufficient. The operation then proceeds to the third-level value (S18), and the fan speed is assessed for suitability based on whether the voltage stabilizes or rises (S19). If not, the fan speed is increased to the third-level value (S18), and the stack voltage remains unstable or does not rise, proceeding to S17. If the fan speed is increased to the third-level value more than three times, the stack voltage is still unstable or does not rise, and the fan speed is adjusted to the maximum speed (S20). The operation then monitors whether the stack voltage stabilizes or rises (S21). If the voltage stabilizes or rises, the operation proceeds to S17, maintaining the fan speed. If not, the stack temperature can no longer be controlled by adjusting the fan, indicating thermal runaway has occurred inside the stack, requiring immediate shutdown and inspection (S22).

[0023] If the voltage drop rate is greater than the first voltage drop rate S02, then determine whether the voltage drop rate of the fuel cell stack is greater than the second voltage drop rate S11. If yes, it indicates that the temperature is rising too quickly, and the fuel cell stack is rapidly cooled down by increasing the fan speed to the third step S18. Subsequent steps are as described above. If no, then determine whether the internal resistance rise rate is greater than the second internal resistance rise rate S12. The rise rate of internal resistance determines the rate of water loss from the proton exchange membrane. If it is too fast, it can easily cause the membrane to dry out rapidly, or even cause membrane perforation. If yes, then proceed directly to S18, increasing the fan speed to the third step value to rapidly increase the fan speed. Subsequent steps are as described above. If no, then determine whether the fuel cell stack temperature is greater than 60°C. S13; If yes, proceed directly to the operation of increasing the fan speed to the third step S18 to quickly increase the fan speed, and the subsequent steps are as described above; If no, determine whether the rise in stack temperature is greater than the second temperature rise rate S14; If yes, proceed directly to S18 to increase the fan speed to the third step to quickly increase the fan speed, and the subsequent steps are as described above; If no, it means that the temperature rise is relatively slow, and the amount of moisture removed due to the rise in internal stack temperature is increased and plays a dominant role, causing the membrane to slowly dry out, so increase the fan speed to the second step value S15 to reduce the stack temperature, and determine whether the fan speed is appropriate and sufficient based on whether the voltage is stable or rising S16; If no, continue to increase the fan speed to the second step value S15, continue to determine the stack voltage change, until the stack is running stably, and proceed to the operation of maintaining the fan speed S17; If the stack voltage has not stabilized or risen after increasing the fan speed to the second step value more than 3 times, it means that the increase in fan speed is far from sufficient; then proceed directly to the operation of increasing the fan speed to the third step S18 to quickly increase the fan speed, and the subsequent steps are as described above.

[0024] 5. The air-cooled reactor control method according to claim 4, characterized in that: the first voltage drop rate is less than the second voltage rise rate; the first internal resistance rise rate is less than the second internal resistance rise rate; the first temperature rise rate is less than the second temperature rise rate; and the first fan speed step value is less than the second step value and the third step value.

[0025] In the above method, the first voltage decrease rate is 1-5 mV / min; the first internal resistance increase rate is 1-5 mΩ / min. The first temperature increase rate is 1-3℃ / min; the first step value is 1000-2000 rpm; the second step value is 2000-2500 rpm; and the third step value is 2500-3000 rpm. The maximum fan speed is 3000-4000 rpm; the second internal resistance increase rate is 5-10 mΩ / min; the second temperature increase rate is 3-5℃ / min; and the second voltage decrease rate is 5-10 mV / min.

[0026] The following are specific examples based on the methods described in this implementation, see Examples 2-4 for details.

[0027] Example 2

[0028] This embodiment primarily uses voltage drop as an example. Under conditions of 60℃ and a current density of 1A / cm², the voltage is unstable and gradually increases, dropping from 0.657V to 0.642V within 1 minute. First, it is determined whether the voltage drop rate is greater than 0.5-5mV / min. If yes, it is further determined whether the voltage drop rate is greater than 5-10mV / mV. If yes, the fan speed is directly increased by the third step. At this point, the voltage begins to rise and eventually stabilizes at 0.657V, and the fan speed is maintained at this value for continued operation.

[0029] Example 3

[0030] This embodiment mainly focuses on the increase of internal resistance, at a temperature of 60°C and a current density of 1A / cm². 2 Under these conditions, the voltage is unstable and gradually increases, decreasing from 0.657V to 0.653V within 1 minute, while the internal resistance decreases from 50mΩcm. 2 Rise to 52 mΩcm 2 First, determine if the voltage drop rate is greater than 0.5-5mV / min. If not, continue to determine if the internal resistance rise rate is greater than the first internal resistance rise rate of 0.5-3mΩ / min. If not, determine if the fuel cell stack temperature is greater than 60℃. If not, determine if the fuel cell stack temperature has decreased or stabilized. If yes, reduce the fan speed by the first step value. At this time, the voltage begins to rise and eventually stabilizes at 0.657V. Continue to run at this fan speed value.

[0031] Example 4

[0032] This embodiment primarily focuses on the increase in internal resistance. Under a current density of 1 A / cm², the voltage is unstable and gradually increases, decreasing from 0.657V to 0.653V within 1 minute, while the internal resistance increases from 50 mΩcm² to 52 mΩcm², and the fuel cell stack temperature rises from 60°C to 64°C. First, it checks if the voltage drop rate is greater than 0.5-5 mV / min. If not, it checks if the internal resistance increase rate is greater than the first increase rate of 0.5-3 mΩ / min. If not, it checks if the fuel cell stack temperature is greater than 60°C. If yes, it checks if the temperature is greater than 65°C. If no, it checks if the temperature increase rate is greater than the second increase rate of 3-5°C / min. If yes, it directly increases the fan speed by the third step. At this point, the voltage continues to decrease, and this process is repeated three times, increasing the fan speed by the third step. The voltage continues to decrease. Finally, the fan speed is increased to the maximum value of 4000 rpm, at which point the voltage begins to rise and eventually stabilizes at 0.657V. This fan speed is then maintained for continued operation.

[0033] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A method for controlling an air-cooled reactor, characterized in that, By monitoring the changes in the internal voltage of the air-cooled reactor and combining the measurement data from the internal resistance meter, the dryness state of the proton exchange membrane in the reactor can be reflected. At the same time, the fan speed can be adjusted according to the temperature changes inside the reactor to ensure stable operation of the reactor and reduce fan auxiliary losses, thereby achieving optimal system efficiency.

2. The air-cooled reactor control method according to claim 1, characterized in that, The air-cooled reactor includes a main body and a measurement section; the main body includes the air-cooled reactor and an external fan; the measurement section includes a temperature measuring instrument, a voltmeter, an ammeter, and an internal resistance meter. The peripheral fan is located outside the air-cooled reactor; The two leads of the voltmeter and ammeter are connected to the positive and negative terminals of the current collector of the fuel cell stack, respectively, to monitor the voltage and current changes of the fuel cell stack; the two leads of the internal resistance meter are connected to the positive and negative terminals of the current collector of the fuel cell stack, respectively, to monitor the internal resistance changes of the fuel cell stack, and further monitor the changes in the water content inside the fuel cell stack.

3. The air-cooled reactor control method according to claim 2, characterized in that, There are three temperature measuring probes, located at different parts of the fuel cell stack core, used to monitor the temperature at different locations in the stack core, ensuring the reliability and uniformity of the measurement.

4. The air-cooled reactor control method according to claim 1, characterized in that, The specific steps are as follows: If an abnormal voltage drop occurs (S01), first determine if the voltage drop rate is greater than the first voltage drop rate (S02). If not, continue to determine if the internal resistance rise rate is greater than the first internal resistance rise rate (S03). If not, further determine if the fuel cell stack temperature is greater than 60℃ (S04). If it is less than or equal to 60℃, it indicates that the internal condition of the fuel cell stack is relatively good. Check if the fuel cell stack temperature drops or stabilizes (S05). If yes, it indicates that the fan speed is too high. At this time, the fan speed needs to be reduced to the first step value (S06), while monitoring whether the fuel cell stack voltage is stable or rising (S07). If yes, it indicates that the fuel cell stack is operating normally and the fan has reached its optimal operating power, reducing the system's auxiliary power consumption. At this time, maintain the fan speed (S17). If not, continue (S06) to reduce the fan speed and continue to determine the fuel cell stack voltage change until the fuel cell stack is operating stably. If the fan speed is reduced to the first step value more than 3 times and the fuel cell stack voltage still does not stabilize or rise, it indicates that there are other problems with the fuel cell stack. At this time, perform the shutdown inspection step (S20). If the stack temperature rises during the determination of whether the stack temperature has decreased or stabilized (S05), then it is determined whether the temperature rise is greater than the first rate of temperature increase (S08). If not, it indicates that the temperature rise is relatively slow, and the amount of moisture removed due to the temperature rise inside the stack is increased and plays a dominant role, causing the membrane to dry slowly. Therefore, the fan speed is increased to the first step value (S09) to reduce the stack temperature. The fan speed is then determined to be appropriate and sufficient based on whether the voltage is stable or rising (S10). If not, the fan speed is increased to the first step value (S09), and the stack voltage change is further determined until the stack is running stably. At this point, the fan speed is maintained (S17). If the stack voltage has not stabilized or risen after increasing the fan speed to the first step value more than 3 times, it indicates that the increase in fan speed is far from sufficient. At this point, the fan speed is increased to the second step value (S15), and the fan speed is determined to be appropriate and sufficient based on whether the voltage is stable or rising (S16). If not, the fan speed is increased to the second step value. (S15) Continue to assess the stack voltage change until the stack operates stably, then proceed to maintain fan speed (S17). If the stack voltage has not stabilized or increased after increasing the second-level fan speed more than three times, it indicates that the increase in fan speed is still far from sufficient. Increase the fan speed to the third-level value (S18), and determine if the fan speed is appropriate and sufficient based on whether the voltage stabilizes or increases (S19). If not, continue increasing the fan speed to the third-level value (S18), and continue to assess the stack voltage change. Furthermore, until the fuel cell stack is running stably, the operation of maintaining fan speed (S17) is entered. If the fan speed is increased more than three times to the third step value and the fuel cell stack voltage has not stabilized or risen, the operation of adjusting the fan to the maximum speed (S20) is entered, and the operation of monitoring whether the fuel cell stack voltage is stable or rising (S21) is entered. If it is stable or rising, the operation of maintaining fan speed (S17) is entered. If not, it means that the fuel cell stack temperature can no longer be controlled by adjusting the fan, thermal runaway has occurred inside the fuel cell stack, and an urgent shutdown inspection is required (S22). If the voltage drop rate is greater than the first voltage drop rate (S02), then determine whether the voltage drop rate of the fuel cell stack is greater than the second voltage drop rate (S11). If yes, it indicates that the temperature is rising too quickly, and the fuel cell stack is rapidly cooled down by increasing the fan speed to the third step (S18), with subsequent steps as described above. If no, then determine whether the internal resistance rise rate is greater than the second internal resistance rise rate (S12). If yes, proceed directly to (S18), increasing the fan speed to the third step value and rapidly increasing the fan speed, with subsequent steps as described above. If no, then determine whether the fuel cell stack temperature is greater than 60°C. (S13); If yes, proceed directly to the operation of increasing the fan speed to the third step (S18) to quickly increase the fan speed, and the subsequent steps are as described above; if no, determine whether the temperature rise of the fuel cell stack is greater than the second temperature rise rate (S14); if yes, proceed directly to (S18) to increase the fan speed to the third step to quickly increase the fan speed, and the subsequent steps are as described above; if no, it indicates that the temperature rise is relatively slow, and the amount of moisture removed due to the temperature rise inside the fuel cell stack increases and plays a dominant role, causing the membrane to slowly dry out, so increase the fan speed to the second step value (S15), thereby... Lower the fuel cell stack temperature and determine whether the fan speed is appropriate and sufficient based on whether the voltage stabilizes or rises (S16). If not, continue to increase the fan speed by the second step (S15) and continue to determine the change in fuel cell stack voltage until the fuel cell stack is running stably, and then proceed to the operation of maintaining the fan speed (S17). If the fuel cell stack voltage has not stabilized or risen after increasing the fan speed by the second step more than 3 times, it means that the increase in fan speed is far from sufficient. Then proceed directly to the operation of increasing the fan speed by the third step (S18) to quickly increase the fan speed. The subsequent steps are as described above.

5. The air-cooled reactor control method according to claim 4, characterized in that, The first rate of voltage decrease is less than the second rate of voltage increase; the first rate of internal resistance increase is less than the second rate of internal resistance increase; the first rate of temperature increase is less than the second rate of temperature increase; and the first step value of fan speed is less than the second step value and less than the third step value.

6. The wind-cooled reactor control method according to claim 4, characterized in that, The first rate of decrease of the voltage is 1-5 mV / min; the first rate of increase of the internal resistance is 1-5 mΩ / min.

7. The air-cooled reactor control method according to claim 4, characterized in that, The first temperature rise rate is 1-3℃ / min; the first step value is 1000-2000rpm; the second step value is 2000-2500rpm; and the third step value is 2500-3000rpm.

8. The air-cooled reactor control method according to claim 4, characterized in that, The maximum speed of the fan is 3000-4000 rpm; the second rate of increase of the internal resistance is 5-10 mΩ / min; the second rate of increase of the temperature is 3-5℃ / min; and the second rate of decrease of the voltage is 5-10 mV / min.

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