Insulation control method and device of fuel cell system, vehicle and medium

Abstract

The invention relates to the technical field of fuel cells, in particular to an insulation control method and device of a fuel cell system, a vehicle and a medium, and the method comprises the following steps: obtaining a current insulation resistance value of an electric pile; if the current insulation resistance value is smaller than a first preset insulation threshold value, executing a preset deionization operation, and under the condition that the deionization operation is completed, obtaining the insulation resistance value of the galvanic pile after deionization; if the insulation resistance value after deionization is larger than a second preset insulation threshold value, it is judged that the fuel cell system meets the starting condition, and otherwise, early warning information is generated according to the insulation resistance value after deionization. Therefore, the problems that in the prior art, after a vehicle stops for a long time, components in a fuel cell cooling loop can separate out ions, the ions can enable the conductivity of a cooling medium to be improved, then the insulation resistance value of a fuel cell system is reduced, and the risk that the vehicle cannot be started still exists are solved, the insulation risk of the fuel cell system is reduced, and the service life of the fuel cell system is prolonged. And the user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and in particular to an insulation control method, device, vehicle and medium for a fuel cell system. Background Art

[0002] When a vehicle is connected to a fuel cell system, if the insulation resistance of the fuel cell system is too low, the insulation resistance of the entire vehicle will become low, causing the vehicle to be unable to start.

[0003] In related technologies, after the vehicle completes the high-voltage power-on operation, once the system insulation value is detected to be too low, the system will automatically start the fuel cell water pump and run it for a period of time. During this period, the deionizer inside the fuel cell system absorbs the ions in the coolant to reduce the conductivity of the coolant in the system cooling circuit, improve the system insulation performance, and ensure that the vehicle can start smoothly and normally.

[0004] However, in the related technology, when the vehicle is shut down for a long time, the components in the fuel cell cooling circuit will release ions, which will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system. There is still a risk that the vehicle cannot start, which needs to be solved urgently. Summary of the invention

[0005] The present invention provides an insulation control method, device, vehicle and medium for a fuel cell system to solve the problem in the related art that when a vehicle is shut down for a long time, components in the fuel cell cooling circuit will precipitate ions, and these ions will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system, but there is still a risk of the vehicle being unable to start. The insulation risk of the fuel cell system is reduced and the user experience is improved.

[0006] A first aspect of an embodiment of the present invention provides an insulation control method for a fuel cell system, comprising the following steps: obtaining a current insulation resistance value of a fuel cell stack; if the current insulation resistance value is less than a first preset insulation threshold value, performing a preset deionization operation, and obtaining the insulation resistance value of the fuel cell stack after deionization when the deionization operation is completed; if the insulation resistance value after deionization is greater than a second preset insulation threshold value, determining that the fuel cell system meets the startup conditions, otherwise, generating a warning message based on the insulation resistance value after deionization.

[0007] Further, in some embodiments, executing the preset deionization operation includes: controlling the operation of the water pump of the fuel cell system, and obtaining the conductivity change rate within a preset time period, and / or the operating time of the water pump; if the conductivity change rate within the preset time period is less than a preset change rate threshold, and / or the operating time is greater than a preset time, it is determined that the deionization operation is completed.

[0008] Further, in some embodiments, generating a warning message based on the post-deionization insulation resistance value includes: obtaining a current conductivity; calculating a reference insulation resistance value based on the current conductivity, and determining whether an absolute value of a difference between the reference insulation resistance value and the post-deionization insulation resistance value is less than or equal to a preset deviation value; if the absolute value of the difference between the reference insulation resistance value and the post-deionization insulation resistance value is less than or equal to the preset deviation value, determining that a deionizer in the fuel cell system is faulty, and generating deionizer replacement information.

[0009] Further, in some embodiments, after determining whether the absolute value of the difference between the reference insulation resistance value and the post-deionization insulation resistance value is less than or equal to the preset deviation value, it further includes: if the absolute value of the difference between the reference insulation resistance value and the post-deionization insulation resistance value is greater than the preset deviation value, determining that a cooling circuit structure in the fuel cell system is faulty, and generating cooling circuit structure fault information.

[0010] Further, in some embodiments, before obtaining the current insulation resistance value of the stack, it further includes: determining whether the fuel cell system is in a shutdown state; if the fuel cell system is in the shutdown state, performing the step of obtaining the current insulation resistance value of the stack.

[0011] According to the insulation control method of the fuel cell system provided by the embodiment of the present invention, a deionization operation is performed when the current insulation resistance value of the stack is less than a first preset insulation threshold. After the deionization operation, when the post-deionization insulation resistance value is less than a second preset insulation threshold, a warning message is generated, solving the problem in the related art that when the vehicle is shut down for a long time, ions will precipitate from the components in the fuel cell cooling circuit, these ions will cause the conductivity of the cooling medium to increase, and further reduce the insulation resistance value of the fuel cell system, and there is still a risk that the vehicle cannot be started, reducing the insulation risk of the fuel cell system and improving the user experience.

[0012] An embodiment of the second aspect of the present invention provides an insulation control device for a fuel cell system. The device includes: an acquisition module, configured to acquire a current insulation resistance value of a stack; a control module, configured to perform a preset deionization operation when the current insulation resistance value is less than a first preset insulation threshold, and acquire a post-deionization insulation resistance value of the stack when the deionization operation is completed; a warning module, configured to determine that the fuel cell system meets the start condition when the post-deionization insulation resistance value is greater than a second preset insulation threshold, otherwise, generate a warning message according to the post-deionization insulation resistance value.

[0013] Further, in some embodiments, the control module is specifically configured to: control the operation of the water pump of the fuel cell system, and obtain the conductivity change rate within a preset time period, and / or, the operation duration of the water pump; if the conductivity change rate within the preset time period is less than a preset change rate threshold, and / or, the operation duration is greater than a preset duration, it is determined that the deionization operation is completed.

[0014] Further, in some embodiments, the warning module is specifically configured to: obtain the current conductivity; calculate a reference insulation resistance value based on the current conductivity, and determine whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to a preset deviation value; if the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, it is determined that the deionizer in the fuel cell system is faulty, and deionizer replacement information is generated.

[0015] Further, in some embodiments, after determining whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, the warning module is further configured to: when the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is greater than the preset deviation value, determine that there is a fault in the cooling circuit structure of the fuel cell system, and generate cooling circuit structure fault information.

[0016] According to the insulation control device of the fuel cell system provided by the embodiment of the present invention, when the current stack insulation resistance value is less than the first preset insulation threshold, the deionization operation is performed. After the deionization operation, when the insulation resistance value after deionization is less than the second preset insulation threshold, a warning message is generated, solving the problem in the related art that when the vehicle is parked for a long time, ions will precipitate from the components in the fuel cell cooling circuit, and these ions will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system, and there is still a risk that the vehicle cannot be started, reducing the insulation risk of the fuel cell system and improving the user experience.

[0017] An embodiment of the third aspect of the present invention provides a vehicle, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the program to implement the insulation control method of the fuel cell system as described in the above embodiments.

[0018] An embodiment of the fourth aspect of the present invention provides a computer-readable storage medium, on which a computer program is stored, and the program is executed by a processor to implement the insulation control method of the fuel cell system as described in the above embodiments. Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 It is a flowchart of an insulation control method for a fuel cell system provided according to an embodiment of the present invention;

[0021] Figure 2 It is a schematic diagram of a vehicle architecture 20 involved in an insulation control method for a fuel cell system according to a specific embodiment of the present invention;

[0022] Figure 3 It is a control flowchart of an insulation control method for a fuel cell system provided according to a specific embodiment of the present invention;

[0023] Figure 4 It is a block schematic diagram of an insulation control device for a fuel cell system provided according to an embodiment of the present invention;

[0024] Figure 5 It is a schematic diagram of the structure of a vehicle provided according to an embodiment of the present invention. Detailed Description of the Embodiments

[0025] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0026] The insulation control method, device, vehicle and medium of the fuel cell system according to the embodiments of the present invention will be described below with reference to the accompanying drawings. Regarding the problem mentioned in the above background technology that when the vehicle is parked for a long time, ions will precipitate from the components in the fuel cell cooling circuit, and these ions will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system, and there is still a risk that the vehicle cannot be started. The present invention provides an insulation control method for a fuel cell system. The problem in the related technology that when the vehicle is parked for a long time, ions will precipitate from the components in the fuel cell cooling circuit, and these ions will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system, and there is still a risk that the vehicle cannot be started is solved, the insulation risk of the fuel cell system is reduced, and the user experience is improved.

[0027] Specifically, Figure 1 It is a flowchart of an insulation control method for a fuel cell system provided according to an embodiment of the present invention.

[0028] As Figure 2 shown, Figure 2Schematic diagram of a vehicle architecture involved in an insulation control method for a fuel cell system according to the present invention. The vehicle architecture 20 includes a fuel cell cooling system 21, a vehicle high-voltage system 22, a vehicle power battery pack 23, a storage battery 24, vehicle high-voltage components 25, a high-pressure water pump 26, and a fifth relay KM5. Among them, the fuel cell cooling system 21 includes a fuel cell controller (Fuel Cell Control Unit, FCU) 211, a fuel cell stack 212, a DC / DC converter 213, a conductivity meter 214, a cooling water pump 215, and a deionizer 216; the DC / DC converter 213 includes a first relay KM1, a second relay KM2, and an insulation monitoring module (Insulation Monitoring Device, IMD) 2131; the vehicle high-voltage system 22 includes a third relay KM3 and a fourth relay KM4.

[0029] Specifically, when the vehicle stops, the first relay KM1, the second relay KM2, the third relay KM3, and the fourth relay KM4 are disconnected in sequence, and the fifth relay KM5 is kept connected. The fuel cell controller 211 and the conductivity meter 214 continue to work, and the insulation monitoring module 2131 inside the DC / DC converter 213 starts to work. By monitoring the current insulation resistance value of the fuel cell stack 212, it is determined whether there is a situation where the insulation resistance value of the whole vehicle becomes low, and whether it is necessary to replace the deionizer or generate a cooling circuit structure fault message.

[0030] As Figure 1 shown, the insulation control method for the fuel cell system includes the following steps:

[0031] In step S101, obtain the current insulation resistance value of the fuel cell stack.

[0032] Among them, the current insulation resistance value of the fuel cell stack refers to the resistance value of the insulating material in the fuel cell stack under the current environmental conditions. It should be noted that the insulation resistance value reflects the ability of the insulating material in the fuel cell stack to isolate current. The higher the resistance value, the better the insulation performance, which can effectively prevent faults such as current leakage and short circuits, and ensure the safety of the fuel cell stack and the electrical equipment and personnel connected thereto. On the contrary, if the insulation resistance value is low, there may be insulation hidden dangers. Therefore, it is necessary to check the insulation resistance value in a timely manner and give an early warning when the insulation resistance value is too low.

[0033] Specifically, the current insulation resistance value of the fuel cell stack can be the ratio of the DC voltage value to the leakage current value flowing through the pair of electrodes after a certain time polarization process ends when a DC voltage is applied between the two electrodes of the insulation structure of the fuel cell stack.

[0034] It should be noted that the method for obtaining the current insulation resistance value of the above-mentioned stack is only exemplary and does not limit the present invention. Those skilled in the art can obtain it according to the actual situation. To avoid redundancy, it will not be elaborated in detail here.

[0035] In step S102, if the current insulation resistance value is less than the first preset insulation threshold, a preset deionization operation is performed, and after the deionization operation is completed, the insulation resistance value of the stack after deionization is obtained.

[0036] Among them, the first preset insulation threshold is the threshold at which an insulation fault may occur in the vehicle. If the current insulation resistance value is less than the first preset insulation threshold, it means that the fuel cell of the vehicle has approached the limit value of the lowest insulation resistance value of the vehicle. When the vehicle is restarted, there is a risk of failure to start. At this time, it is necessary to control the stack water pump (i.e., Figure 2 the cooling water pump 215 in

[0037] As a possible implementation method, assume that the currently monitored insulation resistance value of the stack is Rf2, and the threshold for the vehicle to have an insulation fault is Rt. The first preset insulation threshold can be a preset multiple of Rt. For example, the first preset insulation threshold is 1.1Rt. When the current insulation resistance value Rf2 is less than or equal to the first preset insulation threshold 1.1Rt, a deionization operation is performed in a timely manner.

[0038] As a possible implementation method, in some embodiments, performing the preset deionization operation includes: controlling the water pump of the fuel cell system to run, and obtaining the conductivity change rate within a preset time period, and / or, the running duration of the water pump; if the conductivity change rate within the preset time period is less than the preset change rate threshold, and / or, the running duration is greater than the preset duration, it is determined that the deionization operation is completed.

[0039] Among them, the conductivity change rate is used to measure whether the ion precipitation rate in the stack cooling circuit and the ion adsorption rate of the deionizer reach equilibrium; by monitoring the conductivity change rate, it can be understood whether the deionizer in the stack cooling circuit has fully acted on the coolant; a small conductivity change indicates that through the rotation of the water pump, the ions in the coolant are fully mixed, and the deionizer has fully adsorbed, and the ion precipitation rate in the cooling circuit and the ion adsorption rate of the deionizer have reached equilibrium; the preset time period is any time period during the operation of the water pump, which can be calibrated manually, or determined by experimental personnel according to the actual situation, and will not be specifically limited here.

[0040] Specifically, when performing the preset deionization operation, the embodiments of the present invention can achieve the deionization operation by controlling the operation of the water pump of the fuel cell system, and obtain the conductivity change rate within a preset time period and the operation duration of the water pump during the operation of the water pump. If the conductivity change rate within the preset time period is less than the preset change rate threshold, or the operation duration of the water pump is greater than the preset duration, or the conductivity change rate within the preset time period is less than the preset change rate threshold and the operation duration of the water pump is greater than the preset duration, it is determined that the coolant ions are evenly mixed and the deionizer has fully functioned.

[0041] For example, assume that the preset change rate threshold is 1 μS / cm. If the conductivity change rate within the preset time period obtained during the operation of the water pump is 0.5 μS / cm, it indicates that the conductivity change rate within the preset time period is less than the preset change rate threshold, and it is determined that the coolant ions are evenly mixed and the deionizer has fully functioned. Another example, if the preset duration is 10 minutes and the obtained operation duration of the water pump is 11 minutes, it indicates that the operation duration of the water pump is greater than the preset duration, and it is determined that the coolant ions are evenly mixed and the deionizer has fully functioned.

[0042] It should be noted that a smaller conductivity change rate indicates that the coolant ions in the stack are evenly mixed, that is, the deionizer has fully worked and cannot further increase the stack insulation resistance value. Similarly, when the operation duration of the water pump is greater than the preset duration, it means that the mixing duration of the coolant ions in the stack is greater than the theoretical mixing duration of the coolant ions in the stack. At this time, continuing to operate the water pump cannot increase the stack insulation resistance value either.

[0043] In step S103, if the insulation resistance value after deionization is greater than the second preset insulation threshold, it is determined that the fuel cell system meets the start-up condition; otherwise, a warning message is generated according to the insulation resistance value after deionization.

[0044] Among them, the second preset insulation threshold is the condition threshold for judging whether the fuel cell can be normally started. If the insulation resistance value after deionization is greater than the second preset insulation threshold, it means that the fuel cell can be normally started at this time, and the stack insulation resistance value is continuously monitored; if the insulation resistance value after deionization is less than the second preset insulation threshold, it means that the deionizer still cannot make the stack out of the insulation failure risk after working fully. At this time, a warning message is generated to indicate that there is a fault in the stack.

[0045] Among them, in some embodiments, generating a warning message according to the insulation resistance value after deionization includes: obtaining the current conductivity; calculating a reference insulation resistance value based on the current conductivity, and determining whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to a preset deviation value; if the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, it is determined that the deionizer in the fuel cell system fails, and a deionizer replacement message is generated.

[0046] Among them, the reference insulation resistance value is the insulation resistance value that the deionizer should reach theoretically after completing its work. The reference insulation resistance value can be calculated by using the resistance formula in combination with the physical structure of the fuel cell cooling pipeline. For example, the reference insulation resistance value is calculated through the resistance formula: R = L / σ / S, where L is the length of the cooling pipeline, σ is the conductivity reading, and S is the cross-sectional area of the cooling pipeline; the deionizer failure information is a warning message for replacing the deionizer sent to the vehicle when the deionizer reaches the upper limit of ion absorption and an insulation failure is about to occur.

[0047] Further, in some embodiments, after determining whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, it further includes: if the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is greater than the preset deviation value, it is determined that the cooling path structure in the fuel cell system fails, and a cooling path structure failure message is generated.

[0048] Among them, the cooling path structure failure means that the grounding point of the cooling path has shifted for some reason. At this time, no matter how the deionizer works, the insulation resistance value after deionization will be too different from the reference insulation resistance value due to the failure of the cooling path; the cooling path structure failure information is a warning message for the cooling path structure failure sent to the vehicle when the cooling path fails.

[0049] As a possible implementation method, denote the reference insulation resistance value as Rf1 and the insulation resistance value after deionization as Rf3. If the absolute value of the difference between the reference insulation resistance value Rf1 and the insulation resistance value after deionization Rf3 is less than or equal to 15%, it is determined that the deionizer has basically failed. At this time, the coolant has been fully affected by the deionizer, but the conductivity is still relatively high and the insulation is still relatively low. The deionizer has reached the upper limit of ion absorption, and it is determined that an insulation failure is about to occur, and an insulation warning is issued. Since the deionizer is about to fail, a deionizer replacement warning is also issued at the same time; if the absolute value of the difference between the reference insulation resistance value Rf1 and the insulation resistance value after deionization Rf3 is greater than 15%, it means that the deviation between the theoretical insulation resistance value and the actual insulation resistance value is too large, and it can be determined that the grounding point of the cooling path has shifted for some reason; a cooling path structure failure warning is issued.

[0050] It should be noted that the warning information of the deionizer and the warning information of the cooling circuit structure failure can be transmitted to the current vehicle through the vehicle communication line or through the cloud. The vehicle can use a variety of warning devices to remind the user of the fault. For example, the fault warning can be displayed on the central control screen or the instrument screen of the user's vehicle. Another example is that a sound warning can be given through the buzzer of the user's vehicle. Still another example is that the user's vehicle can be informed of the fault warning information through the warning light of the user's vehicle.

[0051] Thus, the deionization operation is performed when the current insulation resistance value of the fuel cell stack is less than the first preset insulation threshold; and after the deionization operation, a warning information is generated when the insulation resistance value after deionization is less than the second preset insulation threshold.

[0052] In addition, when the vehicle has been stopped for a long time, it is more likely that ions will precipitate from the components in the fuel cell cooling circuit, resulting in a decrease in the insulation resistance value of the fuel cell system, and further leading to the risk of the vehicle being unable to start. Therefore, the embodiment of the present invention can also determine whether the fuel cell system is in a shutdown state to obtain the current insulation resistance value of the fuel cell stack when the fuel cell system is in a shutdown state.

[0053] Among them, in some embodiments, before obtaining the current insulation resistance value of the fuel cell stack, it further includes: determining whether the fuel cell system is in a shutdown state; if the fuel cell system is in a shutdown state, then performing the step of obtaining the current insulation resistance value of the fuel cell stack.

[0054] The shutdown state of the fuel cell system is the state when the vehicle has been normally shut down and the fuel cell is powered off. It should be noted that if the fuel cell system is shut down for a long time, ions may precipitate from the fuel cell cooling circuit components, resulting in an increase in conductivity and a decrease in the overall insulation resistance value of the system, and further causing the vehicle to be unable to start normally. Therefore, insulation monitoring is required when the fuel cell system is shut down.

[0055] To enable those skilled in the relevant art to better understand the insulation control method of the fuel cell system in the embodiment of the present invention, the following will be combined with Figure 2 and Figure 3 specific embodiments for explanation.

[0056] As Figure 3 shown, Figure 3 is a control flow chart of the insulation control method of the fuel cell system provided according to a specific embodiment of the present invention.

[0057] In step S301, the vehicle stops.

[0058] In step S302, the first relay KM1, the second relay KM2, the third relay KM3, and the fourth relay KM4 are disconnected in sequence, while the fifth relay KM5 remains closed, and the fuel cell controller 211, the conductivity meter continue to operate, and the insulation monitoring module starts to operate.

[0059] While step S303 is being executed, step S312 is executed.

[0060] In step S303, the insulation monitoring module continuously monitors the current insulation resistance value Rf2 of the stack.

[0061] While step S304 is being executed, step S312 is executed.

[0062] In step S304, the controller determines whether the IMD monitored insulation value is close to the insulation threshold Rt, and whether the current insulation resistance value Rf2 of the stack is less than or equal to the first preset insulation threshold 1.1Rt. If the current insulation resistance value Rf2 of the stack is not less than or equal to the first preset insulation threshold 1.1Rt, then step S305 is executed; otherwise, return to execute step S303.

[0063] In step S305, request to apply high voltage on the vehicle, control the third relay KM3 and the fourth relay KM4 to close, power on the water pump at high voltage, and the FCU controls the operation of the water pump through CAN communication.

[0064] In step S306, it is judged whether the conductivity change rate within the preset arbitrary time t1 is less than 1 μS / cm, or the time is greater than the preset stop time t2. If the conductivity change rate within the arbitrary time t1 is less than 1 μS / cm or the time is greater than the preset stop time t2, then step S307 is executed; otherwise, return to execute step S305.

[0065] In step S307, the water pump stops running, and it is judged whether the IMD monitored insulation resistance value Rf3 after deionization is greater than the second preset insulation threshold 1.5Rt. If the insulation resistance value Rf3 after deionization is greater than the second preset insulation threshold 1.5Rt, then step S303 is executed; otherwise, step S308 is executed.

[0066] In step S308, read the conductivity meter reading σ at this time, calculate the reference insulation resistance value Rf1 according to the resistance formula R = L / σ / S, and read the IMD stack insulation resistance value Rf3 at this time.

[0067] In step S309, compare the reference insulation resistance value Rf1 and the insulation resistance value Rf3 after deionization, and whether the absolute value of the deviation is less than 15%. If the absolute value of the deviation between the reference insulation resistance value Rf1 and the insulation resistance value Rf3 after deionization is less than 15%, then step S310 is executed; otherwise, step S311 is executed.

[0068] In step S310, if the theoretical insulation resistance and the actual insulation resistance are within the deviation range, it means that the deionizer has basically failed and an insulation failure is about to occur, and an insulation warning is issued, and a warning to replace the deionizer is issued.

[0069] In step S311, the deviation between the theoretical insulation resistance and the actual insulation resistance is too large, indicating that the cooling path grounding point is offset for some reason; a cooling path structure fault warning is issued, and the process ends.

[0070] In step S312, it is determined whether a vehicle start command is received. If no vehicle start command is received, step S303 is executed; otherwise, step S313 is executed.

[0071] In step S313, the insulation monitoring module is disconnected, and the third relay KM3, the fourth relay KM4, the first relay KM1 and the second relay KM2 are closed in sequence, and the fuel cell operates normally.

[0072] In step S314, the vehicle is started successfully.

[0073] According to the insulation control method of the fuel cell system provided in an embodiment of the present invention, a deionization operation is performed when the current stack insulation resistance value is less than a first preset insulation threshold value. After the deionization operation, a warning message is generated when the insulation resistance value after deionization is less than a second preset insulation threshold value. This solves the problem in the related technology that when the vehicle is shut down for a long time, components in the fuel cell cooling circuit will precipitate ions, and these ions will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system, but there is still a risk of the vehicle being unable to start. This reduces the insulation risk of the fuel cell system and improves the user experience.

[0074] Next, the insulation control device of the fuel cell system according to the embodiment of the present invention will be described with reference to the accompanying drawings.

[0075] Figure 4 It is a block diagram of an insulation control device of a fuel cell system provided according to an embodiment of the present invention.

[0076] like Figure 4 As shown, the insulation control device 10 of the fuel cell system includes: an acquisition module 100 , a control module 200 and an early warning module 300 .

[0077] Among them, the acquisition module 100 is used to acquire the current insulation resistance value of the stack; the control module 200 is used to perform a preset deionization operation when the current insulation resistance value is less than the first preset insulation threshold, and after the deionization operation is completed, acquire the insulation resistance value of the stack after deionization; the warning module 300 is used to determine that the fuel cell system meets the start-up condition when the insulation resistance value after deionization is greater than the second preset insulation threshold, otherwise, generate a warning message according to the insulation resistance value after deionization.

[0078] Further, in some embodiments, the control module 200 is specifically configured to: control the water pump of the fuel cell system to run, and acquire the conductivity change rate within a preset time period, and / or, the running duration of the water pump; if the conductivity change rate within the preset time period is less than the preset change rate threshold, and / or, the running duration is greater than the preset duration, it is determined that the deionization operation is completed.

[0079] Further, in some embodiments, the warning module 300 is specifically configured to: acquire the current conductivity; calculate a reference insulation resistance value based on the current conductivity, and determine whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to a preset deviation value; if the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, it is determined that the deionizer in the fuel cell system fails, and a deionizer replacement message is generated.

[0080] Further, in some embodiments, after determining whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, the warning module 300 is further configured to: when the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is greater than the preset deviation value, determine that the cooling path structure in the fuel cell system fails, and generate a cooling path structure failure message.

[0081] It should be noted that the foregoing explanation of the embodiments of the insulation control method for the fuel cell system also applies to the insulation control device of the fuel cell system in this embodiment, and will not be elaborated here.

[0082] According to the insulation control device of the fuel cell system proposed by the embodiment of the present invention, a deionization operation is performed when the current insulation resistance value of the stack is less than the first preset insulation threshold. After the deionization operation, when the insulation resistance value after deionization is less than the second preset insulation threshold, a warning message is generated, solving the problem in the related art that when the vehicle stops for a long time, ions will precipitate from the components in the fuel cell cooling circuit, and these ions will cause the conductivity of the cooling medium to increase, thereby reducing the insulation resistance value of the fuel cell system, and there is still a risk that the vehicle cannot start, reducing the insulation risk of the fuel cell system and improving the user experience.

[0083] Figure 5Schematic structural diagram of a vehicle provided according to an embodiment of the present invention. The vehicle may include:

[0084] A memory 501, a processor 502, and a computer program stored on the memory 501 and executable on the processor 502.

[0085] When the processor 502 executes the program, it implements the insulation control method of the fuel cell system provided in the above embodiment.

[0086] Furthermore, the vehicle further includes:

[0087] A communication interface 503 for communication between the memory 501 and the processor 502.

[0088] The memory 501 is used to store a computer program executable on the processor 502.

[0089] The memory 501 may include a high-speed RAM memory, and may also include a non-volatile memory, such as at least one disk memory.

[0090] If the memory 501, the processor 502, and the communication interface 503 are implemented independently, the communication interface 503, the memory 501, and the processor 502 may be interconnected through a bus and communicate with each other. The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 only a thick line is shown in the figure, but it does not mean that there is only one bus or one type of bus.

[0091] Optionally, in a specific implementation, if the memory 501, the processor 502, and the communication interface 503 are integrated on a chip, the memory 501, the processor 502, and the communication interface 503 may communicate with each other through an internal interface.

[0092] The processor 502 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0093] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the insulation control method of the fuel cell system as described above is implemented.

[0094] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0095] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0096] Any process or method description shown in the flowchart or described in other ways herein can be understood as representing a module, segment, or part of code including one or more executable instructions for implementing a customized logic function or process, and the scope of the preferred embodiments of the present invention includes additional implementations, where the functions can be executed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present invention belong.

[0097] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following well-known technologies in the art can be used: discrete logic circuits having logic gate circuits for implementing logic functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0098] Those of ordinary skill in the art can understand that all or part of the steps carried out in implementing the above-described embodiment methods can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

Claims

1. An insulation control method for a fuel cell system, characterized in that Including the following steps: Obtain the current insulation resistance value of the stack; If the current insulation resistance value is less than the first preset insulation threshold, perform a preset deionization operation, and after completing the deionization operation, obtain the insulation resistance value of the stack after deionization; If the insulation resistance value after deionization is greater than the second preset insulation threshold, determine that the fuel cell system meets the startup conditions; otherwise, generate a warning message based on the insulation resistance value after deionization.

2. The method according to claim 1, characterized in that The execution of the preset deionization operation includes: Control the water pump of the fuel cell system to run, and obtain the conductivity change rate within a preset time period, and / or the running duration of the water pump; If the conductivity change rate within the preset time period is less than the preset change rate threshold, and / or the running duration is greater than the preset duration, determine that the deionization operation is completed.

3. The method according to claim 1, characterized in that, The generation of the warning message based on the insulation resistance value after deionization includes: Obtain the current conductivity; Calculate the reference insulation resistance value based on the current conductivity, and determine whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value; If the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, determine that the deionizer in the fuel cell system is faulty, and generate deionizer replacement information.

4. The method according to claim 3, characterized in that, After determining whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, it further includes: If the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is greater than the preset deviation value, determine that the cooling path structure in the fuel cell system is faulty, and generate cooling path structure fault information.

5. The method according to claim 1, characterized in that, Before obtaining the current insulation resistance value of the stack, it further includes: Determine whether the fuel cell system is in a shutdown state; If the fuel cell system is in the shutdown state, perform the step of obtaining the current insulation resistance value of the stack.

6. An insulation control device for a fuel cell system, characterized in that, The device includes: An acquisition module, configured to obtain the current insulation resistance value of the stack; A control module, configured to perform a preset deionization operation when the current insulation resistance value is less than the first preset insulation threshold, and after completing the deionization operation, obtain the insulation resistance value of the stack after deionization; A warning module, configured to determine that the fuel cell system meets the startup conditions when the insulation resistance value after deionization is greater than the second preset insulation threshold; otherwise, generate a warning message based on the insulation resistance value after deionization.

7. The insulation control device of the fuel cell system according to claim 6, characterized in that, The control module is specifically configured to: Control the water pump of the fuel cell system to run, and obtain the conductivity change rate within a preset time period, and / or the running duration of the water pump; If the conductivity change rate within the preset time period is less than the preset change rate threshold, and / or the running duration is greater than the preset duration, determine that the deionization operation is completed.

8. The insulation control device of the fuel cell system according to claim 6, characterized in that, The warning module is specifically configured to: Obtain the current conductivity; Calculate a reference insulation resistance value based on the current conductivity, and determine whether the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to a preset deviation value; If the absolute value of the difference between the reference insulation resistance value and the insulation resistance value after deionization is less than or equal to the preset deviation value, it is determined that the deionizer in the fuel cell system is faulty, and deionizer replacement information is generated.

9. A vehicle, characterized in that, Comprising: A memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the insulation control method of the fuel cell system according to any one of claims 1-5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to be used to implement the insulation control method of the fuel cell system according to any one of claims 1-5.

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