A control method and device for low temperature start-up of a hydrogen fuel cell system

Abstract

The present invention discloses a control method and device for low-temperature startup of a hydrogen fuel cell system, which relates to the field of fuel cell technology, including: obtaining and judging whether the hydrogen fuel cell system is in a low-temperature startup state; when the hydrogen fuel cell is in a low-temperature startup state, obtaining and judging whether the hydrogen circulation pump is blocked; based on the blocking condition of the hydrogen circulation pump, executing the corresponding pure hydrogen mode strategy, the pure hydrogen mode strategy includes a pressure regulating valve adjustment strategy, an exhaust valve adjustment strategy, and a current adjustment strategy of the stack; obtaining and judging whether the hydrogen circulation pump solves the blocking condition after executing the pure hydrogen mode strategy. The present invention avoids the risk of startup failure caused by freezing of the execution components through a precise control strategy, thereby improving the adaptability of the hydrogen fuel cell system under extreme low temperature conditions and the reliability of the product, and ensuring that the hydrogen fuel cell system can be smoothly started and stably operated in a low temperature environment.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to a control method and device for low-temperature startup of a hydrogen fuel cell system. Background Art

[0002] In recent years, with the enhancement of environmental protection awareness and the advancement of technology, hydrogen fuel cells have been widely used as clean energy in transportation and other fields. However, in extremely cold environments, the startup performance of hydrogen fuel cell systems will be greatly challenged. Especially for hydrogen circulation pumps, since liquid water may remain after the previous use, this water is easy to freeze at low temperatures, causing the hydrogen circulation pump to fail to work properly when restarted. This situation not only affects the startup efficiency of the hydrogen fuel cell system, but also may cause hydrogen deficiency in the anode of the stack, leading to startup failure or even electrode damage.

[0003] Although the existing hydrogen circulation pump design already includes an ice-breaking function, in actual applications, there is still a problem of insufficient hydrogen supply to the fuel cell stack due to insufficient speed at the initial start-up. This problem not only limits the application of hydrogen fuel cell systems in low-temperature environments, but also increases the maintenance cost of the system and reduces the overall reliability of the product. Therefore, a control method for low-temperature start-up of a hydrogen fuel cell system is needed to solve the above problem. Summary of the invention

[0004] The present invention provides a control method and device for low-temperature startup of a hydrogen fuel cell system, which avoids the risk of startup failure due to freezing of execution components through precise control strategies, thereby improving the adaptability of the hydrogen fuel cell system under extreme low temperature conditions and the reliability of the product, and ensuring that the hydrogen fuel cell system can be successfully started and stably operated in a low-temperature environment.

[0005] In order to achieve the above-mentioned object, in a first aspect, the present invention provides a control method for low-temperature startup of a hydrogen fuel cell system, the method being applied to a fuel cell system including a hydrogen circulation pump, a pressure regulating valve, an exhaust valve and a fuel cell stack, comprising:

[0006] Obtaining and determining whether the hydrogen fuel cell system is in a low temperature start-up state;

[0007] When the hydrogen fuel cell is in the low-temperature start-up state, obtaining and determining whether the hydrogen circulation pump is blocked;

[0008] Based on the stall condition of the hydrogen circulation pump, executing a corresponding pure hydrogen mode strategy, wherein the pure hydrogen mode strategy includes the pressure regulating valve adjustment strategy, the exhaust valve adjustment strategy, and the current adjustment strategy of the fuel cell stack;

[0009] Obtain and determine whether the hydrogen circulation pump resolves the stalling condition after executing the pure hydrogen mode strategy.

[0010] Preferably, the obtaining and judging whether the hydrogen fuel cell system is in a low temperature start-up state is specifically:

[0011] Based on the temperature sensor, the motor temperature of the hydrogen circulation pump and the current ambient temperature are obtained, and at the same time, the ambient temperature when the pump was last shut down is read;

[0012] If the current motor temperature of the hydrogen circulation pump is less than 0°C;

[0013] And / or, the current ambient temperature is less than 0°C;

[0014] And / or, the ambient temperature during the last shutdown is less than 0°C;

[0015] It is determined that the fuel cell system is in a low temperature start-up state.

[0016] Preferably, the obtaining and judging whether the hydrogen circulation pump is blocked is specifically:

[0017] Obtaining the real-time rotation speed and current value of the hydrogen circulation pump;

[0018] The real-time rotation speed and the current value are analyzed and compared with the normal start-up threshold of the hydrogen circulation pump to obtain the blocking condition of the hydrogen circulation pump.

[0019] Preferably, the real-time rotation speed and current value are analyzed and compared with the normal start-up threshold of the hydrogen circulation pump to obtain the stall condition of the hydrogen circulation pump, specifically:

[0020] If the real-time speed is lower than the speed threshold during normal startup;

[0021] and / or, the real-time current value is greater than the current threshold value during normal startup;

[0022] It is determined that the hydrogen circulation pump is in a blocked state.

[0023] Preferably, the determining that the hydrogen circulation pump is in a blocked state is specifically as follows:

[0024] If the real-time speed is less than the speed threshold during normal startup, and is greater than or equal to the first preset speed threshold;

[0025] And / or, the real-time current value is greater than the current threshold during normal startup and less than or equal to the first preset current threshold;

[0026] It is judged that the hydrogen circulation pump is in a slightly blocked state;

[0027] If the real-time rotational speed is less than the first preset rotational speed threshold and greater than or equal to the second preset rotational speed threshold;

[0028] and / or, the real-time current value is greater than the first preset current threshold and less than or equal to the second preset current threshold;

[0029] then it is determined that the hydrogen circulation pump is in a moderate stall state;

[0030] If the real-time rotational speed is less than the second preset rotational speed threshold;

[0031] and / or, the real-time current value is greater than the second preset current threshold;

[0032] then it is determined that the hydrogen circulation pump is in a severe stall state.

[0033] Preferably, based on the stall condition of the hydrogen circulation pump, a corresponding pure hydrogen mode strategy is executed, specifically:

[0034] When the stall condition of the hydrogen circulation pump is the mild stall state, a first pure hydrogen mode strategy is executed;

[0035] When the stall condition of the hydrogen circulation pump is the moderate stall state, a second pure hydrogen mode strategy is executed;

[0036] When the stall condition of the hydrogen circulation pump is the severe stall state, a third pure hydrogen mode strategy is executed;

[0037] Based on different pure hydrogen mode strategies, the pressure regulating valve, the exhaust valve, and the current of the fuel cell stack are correspondingly adjusted to solve the stall condition of the hydrogen circulation pump.

[0038] Preferably, based on different pure hydrogen mode strategies, the pressure regulating valve, the exhaust valve, and the current of the fuel cell stack are correspondingly adjusted, specifically:

[0039] The first pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P1, adjusting the frequency of the exhaust valve to N1, and adjusting the current of the fuel cell stack to I1;

[0040] The second pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P2, adjusting the frequency of the exhaust valve to N2, and adjusting the current of the fuel cell stack to I2;

[0041] The third pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P3, adjusting the frequency of the exhaust valve to N3, and adjusting the current of the fuel cell stack to I3;

[0042] The hydrogen pressure P1 < P2 < P3, the frequency of the exhaust valve N1 < N2 < N3, and the current of the fuel cell stack I1 < I2 < I3.

[0043] Preferably, the obtaining and judging whether the hydrogen circulation pump solves the stalling situation after executing the pure hydrogen mode strategy is specifically as follows:

[0044] Obtaining the real-time rotation speed of the hydrogen circulation pump;

[0045] If the real-time speed is greater than or equal to the speed threshold during normal startup;

[0046] and / or, the difference between the real-time rotation speed and the command rotation speed is less than a preset error range threshold;

[0047] It is determined that the hydrogen circulation pump has resolved the blocking condition;

[0048] Otherwise, it is determined that the hydrogen circulation pump has not resolved the stall situation, and the corresponding pure hydrogen mode strategy continues to be executed.

[0049] In a second aspect, the present invention provides a control device for low-temperature startup of a hydrogen fuel cell system, the device being applied to a fuel cell system including a hydrogen circulation pump, a pressure regulating valve, an exhaust valve and a fuel cell stack, comprising:

[0050] A low temperature judgment module, used to obtain and judge whether the hydrogen fuel cell system is in a low temperature start-up state;

[0051] A stall judgment module, used for obtaining and judging whether the hydrogen circulation pump is stalled when the hydrogen fuel cell is in the low-temperature starting state;

[0052] An execution module, configured to execute a corresponding pure hydrogen mode strategy based on the stall condition of the hydrogen circulation pump, wherein the pure hydrogen mode strategy includes the pressure regulating valve adjustment strategy, the exhaust valve adjustment strategy, and the current adjustment strategy of the fuel cell stack;

[0053] The detection module is used to obtain and determine whether the hydrogen circulation pump solves the blocking situation after executing the pure hydrogen mode strategy.

[0054] Preferably, the low temperature judgment module is specifically used for:

[0055] Based on the temperature sensor, the motor temperature of the hydrogen circulation pump and the current ambient temperature are obtained, and at the same time, the ambient temperature when the pump was last shut down is read;

[0056] If the current motor temperature of the hydrogen circulation pump is less than 0°C;

[0057] And / or, the current ambient temperature is less than 0°C;

[0058] And / or, the ambient temperature during the last shutdown is less than 0°C;

[0059] It is determined that the fuel cell system is in a low temperature start-up state.

[0060] The embodiment of the present application discloses a control method and device for low-temperature startup of a hydrogen fuel cell system. The method can accurately determine whether the hydrogen fuel cell system is in a low-temperature startup state by monitoring the motor temperature of the hydrogen circulation pump, the current ambient temperature, and the ambient temperature when the system was shut down last time, so as to prepare in advance for possible stalling problems; by monitoring the real-time speed and current value of the hydrogen circulation pump and comparing them with the threshold value during normal startup, stalling can be discovered in time to avoid system failures caused by failure to handle in time; according to the different degrees of stalling of the hydrogen circulation pump (mild, moderate, and severe), different pure hydrogen mode strategies are adopted to adjust the states of the pressure regulating valve and the exhaust valve and the working current of the stack respectively, effectively solving the stalling problem of the hydrogen circulation pump caused by low temperature and ensuring the stable operation of the hydrogen fuel cell system; after executing the corresponding pure hydrogen mode strategy, the real-time speed of the hydrogen circulation pump is checked again to confirm whether the stalling situation has been solved, ensuring that the system returns to normal working state, significantly improving the startup performance of the hydrogen fuel cell system under low temperature conditions, reducing faults caused by low temperature, extending the service life of the system, and reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0062] Figure 1 A schematic flow chart of a method for controlling low-temperature startup of a hydrogen fuel cell system;

[0063] Figure 2 The figure is a schematic diagram of the structure of a control device for low-temperature startup of a hydrogen fuel cell system. DETAILED DESCRIPTION

[0064] As mentioned in the background technology, although the existing hydrogen circulation pump design already includes an ice-breaking function, in actual applications, there is still a problem of insufficient hydrogen supply to the fuel cell stack due to insufficient speed at the initial start-up. This problem not only limits the application of hydrogen fuel cell systems in low-temperature environments, but also increases the maintenance cost of the system and reduces the overall reliability of the product.

[0065] In order to solve the above problems, the embodiment of the present application proposes a control method for low-temperature startup of a hydrogen fuel cell system, which is applied to a fuel cell system including a hydrogen circulation pump, a pressure regulating valve, an exhaust valve and a fuel cell stack. The solution uses a precise control strategy to avoid the risk of startup failure caused by freezing of the actuator components, thereby improving the adaptability of the hydrogen fuel cell system under extreme low temperature conditions and the reliability of the product, ensuring that the hydrogen fuel cell system can be successfully started and stably operated in a low temperature environment.

[0066] like Figure 1 FIG. 1 is a flow chart of a control method for low-temperature startup of the above hydrogen fuel cell system. Specifically, the method includes the following steps:

[0067] Step S101, obtaining and determining whether the hydrogen fuel cell system is in a low temperature start-up state.

[0068] As mentioned above, the temperature sensor installed in the system is used to obtain the current temperature of the hydrogen circulation pump motor, the current ambient temperature, and the ambient temperature data recorded when the system was last shut down. The collected temperature data is compared with the preset low-temperature start threshold. If any of the following conditions is met, the system is considered to be in a low-temperature start state: the current temperature of the hydrogen circulation pump motor is lower than 0°C; the current ambient temperature is lower than 0°C; the ambient temperature recorded when the system was last shut down is lower than 0°C.

[0069] For example, suppose in a hydrogen fuel cell vehicle, when the vehicle is parked outdoors and the temperature drops to -10°C at night, the system will first detect the current ambient temperature through the temperature sensor before the next start. If the test result shows that the ambient temperature is indeed below 0°C, the control system will determine that it is currently in a low-temperature start state and enter the low-temperature start control process. Another example is that even if the current ambient temperature is a positive number, if the ambient temperature recorded when the vehicle was parked last was -5°C, and the temperature of the hydrogen circulation pump motor is also low (for example, below 0°C), the system will also determine that it is in a low-temperature start state.

[0070] It should be noted that, based on the above-mentioned scheme, those skilled in the art may also adopt a multi-point temperature monitoring scheme, that is, in addition to the hydrogen circulation pump motor temperature and the ambient temperature, temperature monitoring of other key components (such as the fuel cell stack, the pressure regulating valve, etc.) may be added to more comprehensively evaluate the overall temperature condition of the system; adopt a historical temperature trend analysis scheme, that is, introduce a temperature trend analysis algorithm, and predict the temperature change trend in the future through the temperature change data of several consecutive days, so as to make start-up preparations in advance; adopt a user input information scheme, that is, allow the user to manually input or remotely inform the control system of the expected start-up time and environmental conditions through a mobile device, so that the system can enter the preheating or other preparation stages in advance. The above optional schemes all fall within the scope of protection of this application.

[0071] Step S102: when the hydrogen fuel cell is in the low-temperature start-up state, obtaining and determining whether the hydrogen circulation pump is blocked.

[0072] As described above, the real-time speed and current value of the hydrogen circulation pump are continuously obtained through the sensor installed on the hydrogen circulation pump. The real-time speed and current value are compared and analyzed with the preset speed threshold and current threshold during normal startup. If the real-time speed is lower than the speed threshold during normal startup, or the real-time current value is higher than the current threshold during normal startup, it is determined that the hydrogen circulation pump is in a blocked state.

[0073] For example, suppose that in a low temperature start-up test, the speed threshold of the hydrogen circulation pump when it starts normally is 1000RPM and the current threshold is 5A. If the current speed is detected to be 800RPM and the current is 6A, it can be determined that the hydrogen circulation pump is in a stalled state.

[0074] It should be noted that, technical personnel in this field can also adopt a multi-parameter comprehensive judgment scheme based on the above scheme, that is, in addition to the speed and current value, other parameters such as temperature, pressure, etc. can be combined for comprehensive judgment to improve the accuracy of the stall state judgment; adopt a dynamic threshold adjustment scheme, that is, dynamically adjust the speed threshold and current threshold during normal startup according to the working state of the hydrogen circulation pump (such as temperature changes, load differences, etc.) to make it closer to the actual working conditions; adopt a historical data analysis scheme, that is, use historical data to establish a model to analyze the normal working parameters of the hydrogen circulation pump under different environmental conditions, so as to formulate more accurate judgment criteria. The above optional schemes all belong to the protection scope of this application.

[0075] Step S103: Based on the stall condition of the hydrogen circulation pump, executing a corresponding pure hydrogen mode strategy, wherein the pure hydrogen mode strategy includes the pressure regulating valve adjustment strategy, the exhaust valve adjustment strategy and the current adjustment strategy of the fuel cell stack.

[0076] As mentioned above, different pure hydrogen mode strategies are selected according to the blocking degree of the hydrogen circulation pump (mild, moderate, severe). For each blocking degree, corresponding pressure regulating valve adjustment strategies, exhaust valve adjustment strategies and stack current adjustment strategies are formulated. According to the selected strategy, the pressure of the pressure regulating valve, the opening and closing frequency of the exhaust valve and the working current of the stack are adjusted to solve the blocking problem of the hydrogen circulation pump.

[0077] For example, assuming that the hydrogen circulation pump is in a lightly blocked state, the system will select the first pure hydrogen mode strategy; if the hydrogen circulation pump is in a moderately blocked state, the system will select the second pure hydrogen mode strategy; and in a severe blocked state, the third pure hydrogen mode strategy will be adopted.

[0078] It should be noted that, technical personnel in this field may also adopt a multi-stage pressure regulation scheme based on the above scheme, that is, on the basis of the original scheme, more levels of pressure regulation may be introduced, such as P1, P2, P3, P4, etc., to more finely control the hydrogen pressure and adapt to more diverse blocking situations; adopt a dynamic adjustment strategy scheme, that is, dynamically adjust the strategy parameters according to the actual operation of the hydrogen circulation pump. After a period of execution, if the blocking situation improves, the pressure may be appropriately reduced or the exhaust frequency may be reduced. The above optional schemes all fall within the scope of protection of this application.

[0079] S104: Obtain and determine whether the hydrogen circulation pump has resolved the stalling situation after executing the pure hydrogen mode strategy.

[0080] As described above, after the pure hydrogen mode strategy is executed, the speed of the hydrogen circulation pump continues to be monitored in real time. The speed monitored in real time is compared with the speed threshold during normal startup to determine whether the hydrogen circulation pump has returned to normal working state. If the real-time speed is greater than or equal to the speed threshold during normal startup, or the difference between the real-time speed and the command speed is less than the preset error range threshold, it is determined that the hydrogen circulation pump has resolved the stall situation; otherwise, it is determined that the hydrogen circulation pump has not resolved the stall situation.

[0081] For example, assume that the speed threshold of the hydrogen circulation pump during normal startup is 1000RPM, and the preset error range threshold is ±50RPM. After the pure hydrogen mode strategy is executed, the system detects that the real-time speed of the hydrogen circulation pump is 1020RPM, which exceeds the speed threshold during normal startup, so the system determines that the jam has been resolved. If the real-time speed detected after the pure hydrogen mode strategy is executed is 970RPM, although it does not exceed the speed threshold during normal startup, the difference with the command speed of 1000RPM is 30RPM, which is less than the preset error range threshold of ±50RPM, so the system still determines that the jam has been resolved. If the real-time speed detected after the pure hydrogen mode strategy is executed is only 800RPM, which does not exceed the speed threshold during normal startup, and the difference also exceeds the preset error range threshold, the system determines that the jam has not been resolved.

[0082] It should be noted that, technical personnel in this field may also adopt a multi-parameter comprehensive judgment scheme based on the above scheme, that is, in addition to the rotational speed, other parameters such as current value, vibration level, etc. may be combined for comprehensive judgment to improve the accuracy of the judgment; adopt a dynamic threshold adjustment scheme, that is, according to the actual working status of the hydrogen circulation pump at different time points, dynamically adjust the rotational speed threshold and error range threshold during normal startup to adapt to the changing working conditions; adopt a multiple-attempt mechanism scheme, that is, if the initial execution of the pure hydrogen mode strategy fails to solve the problem, the system may automatically enter the multiple-attempt mechanism and re-execute different levels of pure hydrogen mode strategies in a predetermined order until the problem is solved or the maximum number of attempts is reached. The above optional schemes all fall within the scope of protection of this application.

[0083] In order to accurately identify the situation of starting under low temperature conditions and take corresponding measures to ensure the normal start-up and operation of the hydrogen fuel cell system, the acquisition and judgment of whether the hydrogen fuel cell system is in a low temperature start-up state is specifically as follows:

[0084] Based on the temperature sensor, the motor temperature of the hydrogen circulation pump and the current ambient temperature are obtained, and at the same time, the ambient temperature when the pump was last shut down is read;

[0085] If the current motor temperature of the hydrogen circulation pump is less than 0°C;

[0086] And / or, the current ambient temperature is less than 0°C;

[0087] And / or, the ambient temperature during the last shutdown is less than 0°C;

[0088] It is determined that the fuel cell system is in a low temperature start-up state.

[0089] As mentioned above, three key temperature data are obtained through the temperature sensor installed in the system: the current temperature of the hydrogen circulation pump motor; the current ambient temperature; the ambient temperature recorded when the system was last shut down. The three collected temperature data are compared with the threshold value of low temperature startup. If any of the following conditions are met, the hydrogen fuel cell system is judged to be in a low temperature startup state: the current temperature of the hydrogen circulation pump motor is less than 0°C; the current ambient temperature is less than 0°C; the ambient temperature recorded when the system was last shut down is less than 0°C. As long as any of the above conditions is met, the system will consider that it is currently in a low temperature startup state and enter the subsequent low temperature startup control program.

[0090] In order to accurately determine the stalling of the hydrogen circulation pump under the low-temperature startup state and provide a basis for further adopting the corresponding pure hydrogen mode strategy, the acquisition and determination of whether the hydrogen circulation pump is stalled are specifically as follows:

[0091] Obtaining the real-time rotation speed and current value of the hydrogen circulation pump;

[0092] The real-time rotation speed and the current value are analyzed and compared with the normal start-up threshold of the hydrogen circulation pump to obtain the blocking condition of the hydrogen circulation pump.

[0093] As described above, the real-time speed and current value of the hydrogen circulation pump are obtained through the sensor installed on the hydrogen circulation pump. The collected real-time speed and current value are compared and analyzed with the preset normal start threshold value of the hydrogen circulation pump to determine whether the hydrogen circulation pump is in a blocked state.

[0094] In order to accurately determine whether the hydrogen circulation pump is blocked due to low temperature starting conditions and take corresponding control measures accordingly, the real-time speed and current value are analyzed and compared with the normal starting threshold value of the hydrogen circulation pump to obtain the blocking condition of the hydrogen circulation pump, specifically:

[0095] If the real-time speed is lower than the speed threshold during normal startup;

[0096] and / or, the real-time current value is greater than the current threshold value during normal startup;

[0097] It is determined that the hydrogen circulation pump is in a blocked state.

[0098] As described above, the real-time speed and real-time current value of the hydrogen circulation pump are obtained through the sensor. The real-time speed is compared with the speed threshold value during normal startup; at the same time, the real-time current value is compared with the current threshold value during normal startup. If the real-time speed is lower than the speed threshold value during normal startup, or the real-time current value is greater than the current threshold value during normal startup, it is determined that the hydrogen circulation pump is in a blocked state.

[0099] In order to accurately determine the degree of stalling of the hydrogen circulation pump under low temperature starting conditions and take corresponding control measures accordingly, the determination that the hydrogen circulation pump is in a stalled state is specifically as follows:

[0100] If the real-time speed is less than the speed threshold during normal startup, and is greater than or equal to the first preset speed threshold;

[0101] And / or, the real-time current value is greater than the current threshold during normal startup and less than or equal to the first preset current threshold;

[0102] It is judged that the hydrogen circulation pump is in a slightly blocked state;

[0103] If the real-time speed is less than the first preset speed threshold, and greater than or equal to the second preset speed threshold;

[0104] And / or, the real-time current value is greater than a first preset current threshold and less than or equal to a second preset current threshold;

[0105] It is judged that the hydrogen circulation pump is in a moderately blocked state;

[0106] If the real-time rotation speed is less than a second preset rotation speed threshold;

[0107] and / or, the real-time current value is greater than a second preset current threshold;

[0108] It is determined that the hydrogen circulation pump is in a severe stalled state.

[0109] As described above, the real-time speed and real-time current value of the hydrogen circulation pump are obtained by the sensor. The real-time speed and the real-time current value are compared and analyzed with multiple preset thresholds respectively. If the real-time speed is less than the speed threshold during normal startup, but greater than or equal to the first preset speed threshold; and / or the real-time current value is greater than the current threshold during normal startup, but less than or equal to the first preset current threshold, it is judged that the hydrogen circulation pump is in a mild stall state. If the real-time speed is less than the first preset speed threshold, but greater than or equal to the second preset speed threshold; and / or the real-time current value is greater than the first preset current threshold, but less than or equal to the second preset current threshold, it is judged that the hydrogen circulation pump is in a moderate stall state. If the real-time speed is less than the second preset speed threshold; and / or the real-time current value is greater than the second preset current threshold, it is judged that the hydrogen circulation pump is in a severe stall state.

[0110] In order to select a corresponding strategy based on the stall situation and adjust the parameters of related components to effectively solve the stall problem of the hydrogen circulation pump when starting at low temperature, the corresponding pure hydrogen mode strategy is executed based on the stall situation of the hydrogen circulation pump, specifically:

[0111] When the hydrogen circulation pump is in the mildly blocked state, executing the first pure hydrogen mode strategy;

[0112] When the blocking condition of the hydrogen circulation pump is the moderate blocking condition, executing the second pure hydrogen mode strategy;

[0113] When the hydrogen circulation pump is in the severe stall state, executing the third pure hydrogen mode strategy;

[0114] Based on different pure hydrogen mode strategies, the pressure regulating valve, the exhaust valve and the current of the fuel cell stack are adjusted accordingly to solve the blocking situation of the hydrogen circulation pump.

[0115] As described above, first determine the blocked rotation situation of the hydrogen circulation pump, and classify it into a mild blocked rotation state, a moderate blocked rotation state, or a severe blocked rotation state according to the real-time rotation speed and current value. If the hydrogen circulation pump is in a mild blocked rotation state, execute the first pure hydrogen mode strategy; if the hydrogen circulation pump is in a moderate blocked rotation state, execute the second pure hydrogen mode strategy; if the hydrogen circulation pump is in a severe blocked rotation state, execute the third pure hydrogen mode strategy. According to the selected pure hydrogen mode strategy, adjust the working parameters of the pressure regulating valve, the exhaust valve, and the fuel cell stack, specifically including: pressure regulating valve adjustment, that is, according to different pure hydrogen mode strategies, adjust the setting of the pressure regulating valve to change the hydrogen pressure; exhaust valve adjustment, that is, according to different pure hydrogen mode strategies, adjust the opening frequency or time of the exhaust valve to control gas emissions; fuel cell stack current adjustment, that is, according to different pure hydrogen mode strategies, adjust the working current of the fuel cell stack to change the output power of the fuel cell stack.

[0116] In order to select the corresponding pure hydrogen mode strategy according to the blocked rotation degree (mild, moderate, severe) of the hydrogen circulation pump, and accordingly adjust the pressure of the pressure regulating valve, the opening frequency of the exhaust valve, and the working current of the fuel cell stack to solve the blocked rotation problem. Based on different pure hydrogen mode strategies, correspondingly adjust the pressure regulating valve, the exhaust valve, and the current of the fuel cell stack, specifically as follows:

[0117] The first pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P1, adjusting the frequency of the exhaust valve to N1, and adjusting the current of the fuel cell stack to I1;

[0118] The second pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P2, adjusting the frequency of the exhaust valve to N2, and adjusting the current of the fuel cell stack to I2;

[0119] The third pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P3, adjusting the frequency of the exhaust valve to N3, and adjusting the current of the fuel cell stack to I3;

[0120] The hydrogen pressure P1 < P2 < P3, the frequency of the exhaust valve N1 < N2 < N3, and the current of the fuel cell stack I1 < I2 < I3.

[0121] As described above, the first pure hydrogen mode strategy includes: adjusting the pressure regulating valve to make the hydrogen pressure reach P1; adjusting the opening frequency of the exhaust valve to N1; adjusting the current of the fuel cell stack to I1. The second pure hydrogen mode strategy includes: adjusting the pressure regulating valve to make the hydrogen pressure reach P2 (P2 > P1); adjusting the opening frequency of the exhaust valve to N2 (N2 > N1); adjusting the current of the fuel cell stack to I2 (I2 > I1). The third pure hydrogen mode strategy includes: adjusting the pressure regulating valve to make the hydrogen pressure reach P3 (P3 > P2); adjusting the opening frequency of the exhaust valve to N3 (N3 > N2); adjusting the current of the fuel cell stack to I3 (I3 > I2).

[0122] In order to accurately determine the blocking solution of the hydrogen circulation pump after executing the pure hydrogen mode strategy, and decide whether to continue to take corresponding measures according to the judgment result, the acquisition and judgment of whether the hydrogen circulation pump solves the blocking situation after executing the pure hydrogen mode strategy is specifically as follows:

[0123] Obtaining the real-time rotation speed of the hydrogen circulation pump;

[0124] If the real-time speed is greater than or equal to the speed threshold during normal startup;

[0125] and / or, the difference between the real-time rotation speed and the command rotation speed is less than a preset error range threshold;

[0126] It is determined that the hydrogen circulation pump has resolved the blocking condition;

[0127] Otherwise, it is determined that the hydrogen circulation pump has not resolved the stall situation, and the corresponding pure hydrogen mode strategy continues to be executed.

[0128] As described above, the real-time speed of the hydrogen circulation pump is obtained through the sensor. Check whether the real-time speed is greater than or equal to the speed threshold during normal startup; or, check whether the difference between the real-time speed and the command speed is less than the preset error range threshold. If the real-time speed is greater than or equal to the speed threshold during normal startup; or, the difference between the real-time speed and the command speed is less than the preset error range threshold, it is determined that the hydrogen circulation pump has resolved the jam. If the real-time speed is less than the speed threshold during normal startup; and the difference between the real-time speed and the command speed is greater than the preset error range threshold, it is determined that the hydrogen circulation pump has not resolved the jam, and the corresponding pure hydrogen mode strategy needs to continue to be executed.

[0129] Compared with the prior art, this method can accurately determine whether the hydrogen fuel cell system is in a low-temperature startup state by monitoring the motor temperature of the hydrogen circulation pump, the current ambient temperature, and the ambient temperature at the last shutdown, so as to prepare in advance for possible stalling problems; by monitoring the real-time speed and current value of the hydrogen circulation pump and comparing them with the threshold value during normal startup, stalling can be discovered in time to avoid system failure caused by failure to handle in time; according to the different degrees of stalling of the hydrogen circulation pump (mild, moderate, severe), different pure hydrogen mode strategies are adopted to adjust the states of the pressure regulating valve and the exhaust valve and the working current of the fuel cell stack respectively, effectively solving the stalling problem of the hydrogen circulation pump caused by low temperature and ensuring the stable operation of the hydrogen fuel cell system; after executing the corresponding pure hydrogen mode strategy, the real-time speed of the hydrogen circulation pump is checked again to confirm whether the stalling situation has been solved, ensuring that the system returns to normal working state, significantly improving the starting performance of the hydrogen fuel cell system under low temperature conditions, reducing failures caused by low temperature, extending the service life of the system, and reducing maintenance costs.

[0130] Based on the same inventive concept as the above method, the embodiment of the present application also proposes a control device for low-temperature startup of a hydrogen fuel cell system, which is applied to a fuel cell system including a hydrogen circulation pump, a pressure regulating valve, an exhaust valve and a fuel cell stack, such as Figure 2 The figure is a schematic diagram of the structure of a control device for low-temperature startup of a hydrogen fuel cell system, the device comprising:

[0131] A low temperature judgment module, used to obtain and judge whether the hydrogen fuel cell system is in a low temperature start-up state;

[0132] A stall judgment module, used for obtaining and judging whether the hydrogen circulation pump is stalled when the hydrogen fuel cell is in the low-temperature starting state;

[0133] An execution module, configured to execute a corresponding pure hydrogen mode strategy based on the stall condition of the hydrogen circulation pump, wherein the pure hydrogen mode strategy includes the pressure regulating valve adjustment strategy, the exhaust valve adjustment strategy, and the current adjustment strategy of the fuel cell stack;

[0134] The detection module is used to obtain and determine whether the hydrogen circulation pump solves the blocking situation after executing the pure hydrogen mode strategy.

[0135] Preferably, the low temperature judgment module is specifically used for:

[0136] Based on the temperature sensor, the motor temperature of the hydrogen circulation pump and the current ambient temperature are obtained, and at the same time, the ambient temperature when the pump was last shut down is read;

[0137] If the current motor temperature of the hydrogen circulation pump is less than 0°C;

[0138] And / or, the current ambient temperature is less than 0°C;

[0139] And / or, the ambient temperature during the last shutdown is less than 0°C;

[0140] It is determined that the fuel cell system is in a low temperature start-up state.

[0141] Through the description of the above implementation methods, those skilled in the art can clearly understand that the present invention can be implemented by hardware, or by software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present invention can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.), including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each implementation scenario of the present invention.

[0142] Those skilled in the art will appreciate that the accompanying drawings are merely schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily required for implementing the present invention.

[0143] Those skilled in the art will appreciate that the modules in the device in the implementation scenario can be distributed in the device in the implementation scenario according to the implementation scenario description, or can be changed accordingly and located in one or more devices different from the implementation scenario. The modules in the above implementation scenario can be combined into one module, or can be further split into multiple sub-modules.

[0144] The above serial numbers of the present invention are only for description and do not represent the advantages or disadvantages of the implementation scenarios.

[0145] The above disclosure is only a few specific implementation scenarios of the present invention, but the present invention is not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A control method for low temperature startup of a hydrogen fuel cell system, characterized in that: The method is applied to a fuel cell system including a hydrogen circulation pump, a pressure regulating valve, an exhaust valve and a fuel cell stack, and includes: Obtaining and determining whether the hydrogen fuel cell system is in a low temperature start-up state; When the hydrogen fuel cell is in the low-temperature start-up state, obtaining and determining whether the hydrogen circulation pump is blocked; Based on the stall condition of the hydrogen circulation pump, executing a corresponding pure hydrogen mode strategy, wherein the pure hydrogen mode strategy includes the pressure regulating valve adjustment strategy, the exhaust valve adjustment strategy, and the current adjustment strategy of the fuel cell stack; Obtaining and determining whether the hydrogen circulation pump solves the stalling situation after executing the pure hydrogen mode strategy; The obtaining and judging whether the hydrogen circulation pump is blocked is specifically as follows: Obtaining the real-time rotation speed and current value of the hydrogen circulation pump; Analyze and compare the real-time rotation speed and the current value with the normal start-up threshold of the hydrogen circulation pump to obtain the blocking condition of the hydrogen circulation pump; The real-time rotation speed and current value are analyzed and compared with the normal start-up threshold of the hydrogen circulation pump to obtain the blocking condition of the hydrogen circulation pump, specifically: If the real-time speed is lower than the speed threshold during normal startup; and / or, the real-time current value is greater than the current threshold value during normal startup; It is judged that the hydrogen circulation pump is in a blocked state; The determination that the hydrogen circulation pump is in a blocked state is specifically as follows: If the real-time speed is less than the speed threshold during normal startup, and is greater than or equal to the first preset speed threshold; And / or, the real-time current value is greater than the current threshold during normal startup and less than or equal to the first preset current threshold; It is judged that the hydrogen circulation pump is in a slightly blocked state; If the real-time speed is less than the first preset speed threshold, and greater than or equal to the second preset speed threshold; And / or, the real-time current value is greater than a first preset current threshold and less than or equal to a second preset current threshold; It is judged that the hydrogen circulation pump is in a moderately blocked state; If the real-time rotation speed is less than a second preset rotation speed threshold; and / or, the real-time current value is greater than a second preset current threshold; It is judged that the hydrogen circulation pump is in a severe stalled state; Based on the stall condition of the hydrogen circulation pump, the corresponding pure hydrogen mode strategy is executed, specifically: When the hydrogen circulation pump is in the mildly blocked state, executing the first pure hydrogen mode strategy; When the blocking condition of the hydrogen circulation pump is the moderate blocking condition, executing the second pure hydrogen mode strategy; When the hydrogen circulation pump is in the severe stall state, executing the third pure hydrogen mode strategy; Based on different pure hydrogen mode strategies, the current of the pressure regulating valve, the exhaust valve and the fuel cell stack are adjusted accordingly to solve the blocking of the hydrogen circulation pump; Based on different pure hydrogen mode strategies, the pressure regulating valve, the exhaust valve and the current of the fuel cell stack are adjusted accordingly, specifically: The first pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P1, adjusting the frequency of the exhaust valve to N1, and adjusting the current of the fuel cell stack to I1; The second pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P2, adjusting the frequency of the exhaust valve to N2, and adjusting the current of the fuel cell stack to I2; The third pure hydrogen mode strategy includes adjusting the pressure regulating valve to make the hydrogen pressure reach P3, adjusting the frequency of the exhaust valve to N3, and adjusting the current of the fuel cell stack to I3; The hydrogen pressure P1 < P2 < P3, the frequency of the exhaust valve N1 < N2 < N3, and the current of the fuel cell stack I1 < I2 < I3.

2. The method according to claim 1, characterized in that The obtaining and judging whether the hydrogen fuel cell system is in a low-temperature start state is specifically as follows: Based on the temperature sensor, obtain the motor temperature of the current hydrogen circulation pump and the current ambient temperature, and at the same time read the ambient temperature at the previous shutdown; If the motor temperature of the current hydrogen circulation pump is less than 0°C; and / or, the current ambient temperature is less than 0°C; and / or, the ambient temperature at the previous shutdown is less than 0°C; Then it is determined that the fuel cell system is in a low-temperature start state.

3. The method according to claim 1, characterized in that The obtaining and judging whether the hydrogen circulation pump solves the stuck-rotation situation after executing the pure hydrogen mode strategy is specifically as follows: Obtain the real-time rotation speed of the hydrogen circulation pump; If the real-time rotation speed is greater than or equal to the rotation speed threshold at normal start; and / or, the difference between the real-time rotation speed and the commanded rotation speed is less than the preset error range threshold; Then it is determined that the hydrogen circulation pump has solved the stuck-rotation situation; Otherwise, it is determined that the hydrogen circulation pump has not solved the stuck-rotation situation, and continue to execute the corresponding pure hydrogen mode strategy.

4. A control device for low temperature startup of a hydrogen fuel cell system based on the method according to any one of claims 1 to 3, characterized in that: The device is applied to a fuel cell system including a hydrogen circulation pump, a pressure regulating valve, an exhaust valve, and a fuel cell stack, and includes: A low-temperature judgment module, used to obtain and judge whether the hydrogen fuel cell system is in a low-temperature start state; A stuck-rotation judgment module, used to obtain and judge whether the hydrogen circulation pump is stuck when the hydrogen fuel cell is in the low-temperature start state; An execution module, used to execute the corresponding pure hydrogen mode strategy based on the stuck-rotation situation of the hydrogen circulation pump, and the pure hydrogen mode strategy includes the pressure regulating valve adjustment strategy, the exhaust valve adjustment strategy, and the fuel cell stack current adjustment strategy; A detection module, used to obtain and judge whether the hydrogen circulation pump solves the stuck-rotation situation after executing the pure hydrogen mode strategy.

5. The device according to claim 4, characterized in that The low-temperature judgment module is specifically used for: Based on the temperature sensor, obtain the motor temperature of the current hydrogen circulation pump and the current ambient temperature, and at the same time read the ambient temperature at the previous shutdown; If the motor temperature of the current hydrogen circulation pump is less than 0°C; and / or, the current ambient temperature is less than 0°C; and / or, the ambient temperature at the previous shutdown is less than 0°C; Then it is determined that the fuel cell system is in a low-temperature start state.

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