A control method, apparatus, controller, and storage medium for a fuel cell system.

Abstract

This application discloses a control method, apparatus, controller, and storage medium for a vehicle fuel cell system. The method and apparatus are applied to the controller of the vehicle fuel cell system. Specifically, it involves calculating an operating condition compensation amount based on the current state of the fuel cell stack under dynamic and steady-state operating conditions; calculating a compensation coefficient based on the current state of the fuel cell stack under steady-state operating conditions; correcting the current operating conditions based on the operating condition compensation amount and the compensation coefficient to obtain optimal control conditions; and controlling the vehicle fuel cell based on the optimal control conditions. This ensures that the fuel cell stack is always in the most suitable operating state, reducing performance losses in various polarization processes and improving stack performance and lifespan.

Description

Technical Field

[0001] This application relates to the field of new energy technology, and more specifically, to a control method, device, controller, and storage medium for a fuel cell system. Background Technology

[0002] The continuous and stable power output of a fuel cell system depends on a continuous and stable supply of reactants, timely removal of reaction products, and good control of temperature and humidity. This necessitates effective fuel cell control methods to manage the fuel cell stack. Currently, fuel cell system control primarily relies on bench and vehicle calibration. This involves conducting sensitivity experiments under steady-state conditions on various operating conditions, including hydrogen and air inlet / outlet pressures and metering ratios, operating temperature, and hydrogen exhaust frequency, to determine the optimal operating conditions for each current density. These operating conditions are then embedded into the control software in the form of a calibration table. During operation, the controller retrieves the corresponding operating conditions in real-time based on the current current density and uses them as control setpoints for closed-loop control of each submodule. Figure 1 As shown.

[0003] The problem with existing solutions is that the calibration table stores the optimal operating conditions obtained under steady-state conditions, while fuel cell systems operate under dynamic conditions for most of the time. Since there are significant differences between the two operating conditions, the operating conditions calibrated under steady-state conditions cannot be fully applied to dynamic conditions, resulting in poor performance and short lifespan of automotive fuel cell systems. Summary of the Invention

[0004] In view of this, this application provides a control method, apparatus and controller for a fuel cell system to improve the performance and lifespan of a vehicle fuel cell system.

[0005] To achieve the above objectives, the following solution is proposed:

[0006] A control method for a fuel cell system, applied to a controller of the fuel cell system, the control method comprising the steps of:

[0007] The operating condition compensation amount is calculated based on the current stack state of the fuel cell system under dynamic operating conditions and the current stack state under steady-state operating conditions.

[0008] Calculate the compensation coefficient based on the current state of the fuel cell stack under the aforementioned steady-state operating conditions;

[0009] The current operating conditions are corrected based on the compensation amount and the compensation coefficient to obtain the optimal control conditions;

[0010] The vehicle fuel cell is controlled according to the optimal control conditions.

[0011] Optionally, the step of calculating the operating condition compensation amount based on the current stack state of the fuel cell system under dynamic operating conditions and the current stack state under steady-state operating conditions includes the following steps:

[0012] Detect the current status of the fuel cell stack in the fuel cell system;

[0013] The deviation between the current state of the fuel cell stack under the dynamic operating condition and the current state of the fuel cell stack under the steady-state operating condition is calculated to obtain the operating condition compensation amount.

[0014] Optionally, the current state of the fuel cell stack includes high-frequency impedance and low-frequency impedance.

[0015] Optionally, the step of calculating the compensation coefficient based on the current state of the fuel cell stack under the steady-state operating condition includes the following steps:

[0016] The fuel cell stack status diagnosis result is determined based on the current state of the fuel cell stack under the aforementioned steady-state operating conditions.

[0017] The compensation coefficient is determined based on the results of the fuel cell condition diagnosis.

[0018] A control device for a fuel cell system, applied to a controller of the fuel cell system, the control device comprising:

[0019] The first calculation module is configured to calculate the operating condition compensation amount based on the current stack state of the fuel cell system under dynamic operating conditions and the current stack state under steady-state operating conditions.

[0020] The second calculation module is configured to calculate the compensation coefficient based on the current state of the fuel cell stack under the steady-state operating conditions.

[0021] The correction execution module is configured to correct the current operating conditions based on the operating condition compensation amount and the compensation coefficient to obtain the optimal control conditions;

[0022] The control execution module is configured to control the vehicle fuel cell according to the optimal control conditions.

[0023] Optionally, the first computing module includes:

[0024] The status detection unit is configured to detect the current status of the fuel cell stack of the fuel cell system;

[0025] The compensation calculation unit is configured to calculate the deviation between the current state of the fuel cell stack under the dynamic operating condition and the current state of the fuel cell stack under the steady-state operating condition, and obtain the operating condition compensation amount.

[0026] Optionally, the current state of the fuel cell stack includes high-frequency impedance and low-frequency impedance.

[0027] Optionally, the second computing module includes:

[0028] The first determining unit is configured to determine the stack state diagnosis result based on the current state of the stack under the steady-state operating condition.

[0029] The second determining unit is configured to determine the compensation coefficient based on the stack condition diagnosis results.

[0030] A controller for use in a vehicle fuel cell, the controller comprising at least one processor and a memory connected to the processor, wherein:

[0031] The memory is used to store computer programs or instructions;

[0032] The processor is used to execute the computer program or instructions to enable the controller to implement the control method described above.

[0033] A storage medium is applied to a controller, the storage medium carrying one or more computer programs that can be executed by the controller to enable the controller to implement the control method described above.

[0034] As can be seen from the above technical solution, this application discloses a control method, device, controller, and storage medium for a vehicle fuel cell system. This method and device are applied to the controller of the vehicle fuel cell system. Specifically, it involves calculating the operating condition compensation amount based on the current state of the fuel cell stack under dynamic operating conditions and the current state of the fuel cell stack under steady-state operating conditions; calculating the compensation coefficient based on the current state of the fuel cell stack under steady-state operating conditions; correcting the current operating conditions based on the operating condition compensation amount and the compensation coefficient to obtain the optimal control conditions; and controlling the vehicle fuel cell based on the optimal control conditions. This ensures that the fuel cell stack is always in the most suitable operating state, reducing performance losses in various polarization processes and improving the performance and lifespan of the fuel cell stack. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the control logic of a traditional fuel cell system.

[0037] Figure 2 This is a schematic diagram showing the polarization curves of a fuel cell system and the performance losses in each reaction process.

[0038] Figure 3 This is a schematic diagram of the AC impedance spectrum of a fuel cell system and the performance loss of each reaction process.

[0039] Figure 4 This is a schematic diagram showing the stack polarization performance and corresponding operating points of a fuel cell system under steady-state and dynamic operating conditions.

[0040] Figure 5 This is a flowchart of a control method for a fuel cell system according to an embodiment of this application;

[0041] Figure 6 This is a schematic diagram showing the measurement of high-frequency and low-frequency impedances of a fuel cell system.

[0042] Figure 7 A schematic diagram of the implementation scheme for AC impedance measurement of a fuel cell system;

[0043] Figure 8 This is a schematic diagram of the closed-loop control logic of a fuel cell system based on stack condition monitoring.

[0044] Figure 9 A flowchart illustrating the closed-loop control process of a fuel cell system based on stack condition monitoring.

[0045] Figure 10a This is a graph showing the test results of high-frequency impedance under dynamic operating conditions in an embodiment of this application.

[0046] Figure 10b This is a graph showing the test results of low-frequency impedance under dynamic operating conditions according to an embodiment of this application.

[0047] Figure 11 This is a block diagram of the control device of the fuel cell system according to an embodiment of this application;

[0048] Figure 12 This is a block diagram of the controller according to an embodiment of this application. Detailed Implementation

[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0050] The polarization curves of a fuel cell system reflect its performance under different discharge loads, such as... Figure 2As shown, the polarization curve contains three main performance losses: activation loss, ohmic loss, and mass transfer loss. These three performance losses correspond to three processes in the operation of a fuel cell: charge transfer during the electrochemical reaction, the transfer of electrons and protons in the conductive medium, and the transport of reactants to the reaction site. Improving the performance of a fuel cell system is the process of reducing these three performance losses.

[0051] AC impedance spectroscopy is the most effective method for distinguishing performance losses in a fuel cell system in situ. The conventional AC impedance measurement method involves applying a small sinusoidal current perturbation, i(t) = I0 sin(wt), and then monitoring the system's voltage response, v(t) = V0 sin(wt+φ).

[0052] Where i(t) and v(t) represent the current and voltage at time t, I0 and V0 are the amplitudes of the current and voltage signals, and w is the angular frequency. Generally, the voltage response of the system will exhibit a phase shift relative to the current perturbation; this phase shift effect is described by φ. Therefore, the sinusoidal impedance response of the fuel cell is:

[0053]

[0054] The impedance response of a system can also be expressed in complex form as real and imaginary parts:

[0055]

[0056] By applying sinusoidal perturbations from high to low frequencies (typically 10kHz-0.1Hz), calculating the impedance response at each perturbation frequency, and plotting it on a Nyquist plot, the AC impedance spectrum can be obtained. Figure 3 As shown in the figure, each point represents the impedance response of the fuel cell at the current frequency. According to the mechanism of each reaction process in the fuel cell system, the high-frequency region of the AC impedance spectrum corresponds to ohmic loss, the mid-frequency region corresponds to activation loss, and the low-frequency region corresponds to mass transfer loss. Therefore, by measuring and analyzing the impedance at different frequencies, the magnitude of the performance loss of each reaction process in the fuel cell can be obtained.

[0057] This application describes a method for real-time acquisition of optimal operating conditions during the dynamic operation of a fuel cell stack under vehicle conditions. Based on this, a closed-loop control method is implemented to improve the efficiency of the fuel cell system, and by improving efficiency, its lifespan is extended. The specific process is as follows.

[0058] First, the operating states of the fuel cell system under steady-state and dynamic conditions are analyzed, such as... Figure 4As shown in the figure, the different polarization curves represent the polarization performance of the fuel cell system under different conditions. Curve 1 represents the polarization performance under standard operating conditions, while curves 2 and 3 represent the polarization performance when the operating state of the fuel cell system deviates from the standard conditions. Point S in the figure represents the fuel cell system operating stably under standard conditions at a current density of j0, at which point the stack voltage is U0. The dashed line connecting A, B, and C represents a dynamic operating path of the stack, where point B represents the moment when the current density is j0 in this dynamic condition, and the corresponding voltage is U1. Point B does not coincide with point S, which also has a current density of j0, because there is a difference between the dynamic and steady-state operating conditions of the fuel cell system. The optimal operating condition corresponding to point S is the one obtained from bench calibration under steady-state conditions. The optimal operating condition corresponding to point B is: Since the stack states at points S and B are different, M0 and M1 should be different combinations of operating conditions.

[0059] Figure 4 The voltage at point S can be expressed as:

[0060] U0=OCV-η act0 -η ohmic0 -η conc0 (3)

[0061] The voltage at point B can be expressed as:

[0062] U1=OCV-η act1 -η ohmic1 -η conc1 (4)

[0063] Where, η act η ohmic η conc Let S represent activation loss, ohmic loss, and mass transfer loss, respectively. Then, the voltage difference between point S (steady state) and point B (dynamic state) can be expressed as:

[0064] ΔU=U1-U0=(η act1 -η act0 )+(η ohmic1 -η ohmic0 )+(η conc1 -η conc0 )=Δη act +Δη ohmic +Δη conc (5)

[0065] The relationship between the performance loss differences and each reaction process is as follows:

[0066] Δη act =f(ΔR) ct ,j0) (6)

[0067] Δη ohmic =ΔR ohmic ×j0 (7)

[0068] Δη conc =g(ΔR) conc ,j0) (8)

[0069] Where R ct R ohmic R conc These represent the activation impedance, ohmic impedance, and mass transfer impedance, respectively, and the difference between them under dynamic and steady-state conditions is:

[0070] ΔR ct =R ct1 -R ct0 (9)

[0071] ΔR ohmic =R ohmic1 -R ohmic0 (10)

[0072] ΔR conc =R conc1 -R conc0 (11)

[0073] High and low frequency impedance and R ct R ohmic R conc The relationship is:

[0074] ΔR ohmic =ΔHFR=HFR1-HFR0 (12)

[0075] LFR=α(j)R ct +β(j)R conc (13)

[0076] HFR (High frequency resistance) is the high-frequency impedance, and LFR (Low frequency resistance) is the low-frequency impedance.

[0077] Without considering the effect of concentration on the reversible potential, the mass transfer loss is essentially due to the increase in activation loss, i.e.:

[0078]

[0079] Therefore:

[0080] ΔR conc =γ(j)ΔR ct (15)

[0081] and then:

[0082] ΔLFR=LFR1-LFR0=α(j)(ΔR ct )+β(j)(ΔR conc )=α(j)(ΔR ct )+β(j)γ(j)(ΔR ct )=δ(j)ΔR ct (16)

[0083] Where α(j), β(j), γ(j), and δ(j) are all functions of the current density j.

[0084] Based on the above analysis, this application proposes the following specific embodiments.

[0085] Example 1

[0086] Figure 5 This is a flowchart illustrating a control method for a fuel cell system according to an embodiment of this application.

[0087] like Figure 5 As shown, the control method provided in this embodiment is applied to the controller of a fuel cell system, and is used to control the fuel cell system based on the hardware device of the controller, so as to improve the efficiency of the fuel cell system. The controller can be understood as a computer or embedded device with data computing and information processing capabilities. The control method provided in this application includes the following steps:

[0088] S1. Calculate the operating condition compensation amount based on the current state of the fuel cell stack under dynamic and steady-state conditions.

[0089] This involves calculating the current state of the fuel cell stack under dynamic operating conditions and the current state of the fuel cell stack under steady-state operating conditions to obtain the operating condition compensation amount for the fuel cell system. The specific calculation steps are as follows:

[0090] First, the current state of the fuel cell stack is detected, specifically its current state under dynamic operating conditions and steady-state operating conditions. This invention employs impedance testing at two selected frequencies, one in the high-frequency region and the other in the low-frequency region.

[0091] like Figure 6 As shown, the high-frequency impedance frequency should be selected close to the intersection of the impedance spectrum and the real axis, such as 1000Hz, while the low-frequency impedance should be selected in the frequency band where activation and mass transfer processes work together, such as 10Hz. Then, the current state of the fuel cell stack is obtained based on the real-time measurement results of the high-frequency and low-frequency impedances. The current state of the fuel cell stack is represented by the stack status factor (ssf), which includes the high-frequency impedance (HFR) and the low-frequency impedance (LFR), i.e., ssf(HFR,LFR).

[0092] Then, based on the deviation between the current state of the fuel cell stack under dynamic operating conditions and the current state of the fuel cell stack under steady-state operating conditions, the operating condition compensation amount is obtained. The current state of the fuel cell stack under steady-state operating conditions, ssf0(HFR, LFR), is obtained through bench testing and pre-stored in the controller, while the current state of the fuel cell stack under dynamic operating conditions, ssf1(HFR, LFR), is measured online in real time. When calculating this compensation amount, the operating condition compensation amount ΔM is determined by analyzing the deviation of the fuel cell stack state factors between the dynamic operating process (point B) and the steady-state operating process (point S), i.e.:

[0093] ΔM=w1(ΔHFR)+w2(ΔLFR) (17)

[0094] Where w1 and w2 are weighting coefficients determined in advance through sensitivity experiments.

[0095] S2. Calculate the compensation coefficient based on the current state of the fuel cell stack under the steady-state operating conditions.

[0096] That is, the compensation coefficient is calculated based on the current state of the fuel cell stack under steady-state operating conditions. The specific process is as follows:

[0097] First, determine the stack condition diagnosis results (D,F,S) based on the current state of the stack under steady-state operating conditions.

[0098] Then, the compensation coefficient is determined based on the stack condition diagnosis results (D,F,S). (D, F, S) correspond to the following faults in the fuel cell stack: dry, flooding, and starvation, respectively. The compensation coefficients are... Different values ​​are used when different faults occur in the fuel cell stack.

[0099] S3. Correct the current operating conditions based on the compensation amount and compensation coefficient to obtain the optimal control conditions.

[0100] That is, based on the compensation amount and compensation coefficient of the operating conditions, and using a preset calculation method, the current operating conditions are... After correction, the current optimal control conditions are obtained. The specific calculation formula is as follows:

[0101] M1(P air ) = M0(P air )*(1+f air *ΔM) (18)

[0102]

[0103] M1(T) = M0(T) * (1 + f T*ΔM) (20)

[0104] in, The optimal operating conditions at point S under steady-state conditions are given. The optimal operating conditions are those corresponding to operation point B during dynamic operation.

[0105] S4. Control the vehicle fuel cell according to the optimal control conditions.

[0106] During the operation of the fuel cell system, the stack is controlled according to the above-mentioned optimal control conditions, so that the stack is always in the most suitable working state, reducing the performance loss of each polarization process, reducing the occurrence of irreversible losses, and improving the performance and lifespan of the stack.

[0107] As can be seen from the above technical solution, this embodiment provides a control method for a fuel cell system. This method is applied to the controller of the fuel cell system, specifically by calculating the operating condition compensation amount based on the current state of the fuel cell stack under dynamic and steady-state conditions; calculating the compensation coefficient based on the current state of the fuel cell stack under steady-state conditions; correcting the current operating conditions based on the operating condition compensation amount and the compensation coefficient to obtain the optimal control conditions; and controlling the vehicle fuel cell based on the optimal control conditions. This ensures that the fuel cell stack is always in the most suitable operating state, reducing performance losses in various polarization processes and improving the performance and lifespan of the fuel cell stack.

[0108] like Figure 7 As shown in one specific embodiment of this application, during the operation of the fuel cell system, a small-amplitude, multi-frequency superimposed sinusoidal excitation current is injected into the fuel cell stack through the system's built-in DC-DC converter. The amplitude can be selected from 2 to 5A, and the superposition frequency can be selected from 10Hz and 1000Hz. The AC components on the bus current and bus voltage at the output terminal of the modulated fuel cell stack are measured by the current sensor and conditioning circuit built into the DC-DC converter, and transmitted to the high-speed sampling port of the system controller FCU through the low-voltage wiring harness. The analog current and voltage signals are acquired at high speed in the FCU, and the current fuel cell stack state factor ssf1 can be obtained by calculating the high and low frequency impedances (HFR, LFR) in real time through the time-frequency transformation algorithm.

[0109] By using the real-time calculated ssf1 from the FCU and the pre-stored ssf0 of the stack under the same electrically dense steady-state standard conditions within the FCU, stack condition diagnosis and calculation of stack operating condition compensation ΔM can be achieved. The stack condition diagnosis logic based on HFR and LFR is shown in Table 1. Here, "—" indicates that it remains essentially unchanged relative to the reference value; "↑" indicates that it rises above the reference value exceeding the threshold; and "↓" indicates that it falls below the reference value exceeding the threshold.

[0110]

[0111] Table 1

[0112] fuel cell stack condition diagnosis correspondence Figure 7 Box 1 in the middle of the figure shows the calculation of the compensation amount ΔM for the fuel cell stack operating conditions. Figure 8 Box 2 in the middle of the figure. The operating condition compensation coefficient can be obtained from the stack condition diagnosis results (D,F,S). Multiply by ΔM and add to the steady-state operating conditions pre-stored in the controller. Figure 8 The updated optimal operating conditions can be obtained from node 3. It is used as the control setpoint for each submodule for closed-loop control.

[0113] Meanwhile, the FCU continuously calculates the stack state factor ssf1. If the closed-loop control fails to achieve abs(ssf1-ssf0) within a preset time, the result will be calculated. <Thr ssf That is, the absolute difference between ssf1 and ssf0 is less than the threshold Thr. ssf Then the FCU will actively reduce the set power Δp. Figure 8 Node 4), that is, ensuring stable operation of the fuel cell stack by limiting power output. The closed-loop control process based on fuel cell stack condition monitoring described above is as follows: Figure 9 As shown, Figure 10a and Figure 10b Displayed based on Figure 7 The test results of HFR(a) and LFR(b) implemented by the scheme under dynamic working conditions.

[0114] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0115] Although the operations are described in a specific order, this should not be construed as requiring these operations to be performed in the specific order shown or in a sequential order. In certain environments, multitasking and parallel processing may be advantageous.

[0116] It should be understood that the steps described in the method embodiments of this disclosure may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect.

[0117] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including but not limited to object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer.

[0118] Example 2

[0119] Figure 11 This is a block diagram of a control device for a fuel cell system according to an embodiment of this application.

[0120] like Figure 11 As shown, the control device provided in this embodiment is applied to the controller of a fuel cell system. It is used to control the fuel cell system based on the hardware of the controller, thereby improving the efficiency of the fuel cell system. The controller can be understood as a computer or embedded device with data computing and information processing capabilities. The control device provided in this application includes a first computing module 10, a second computing module 20, a correction execution module 30, and a control execution module 40.

[0121] The first calculation module is used to calculate the operating condition compensation amount based on the current state of the fuel cell stack under dynamic and steady-state operating conditions.

[0122] This module calculates the current state of the fuel cell stack under dynamic and steady-state conditions to obtain the operating condition compensation amount for the fuel cell system. It includes a state detection unit and a compensation amount calculation unit.

[0123] The state detection unit is used to detect the current state of the fuel cell stack, that is, to detect its current state under dynamic operating conditions and steady-state operating conditions. This invention performs impedance testing by selecting one frequency each in the high-frequency and low-frequency regions.

[0124] like Figure 6 As shown, the high-frequency impedance frequency should be selected close to the intersection of the impedance spectrum and the real axis, such as 1000Hz, while the low-frequency impedance should be selected in the frequency band where activation and mass transfer processes work together, such as 10Hz. Then, the current state of the fuel cell stack is obtained based on the real-time measurement results of the high-frequency and low-frequency impedances. The current state of the fuel cell stack is represented by the stack status factor (ssf), which includes the high-frequency impedance (HFR) and the low-frequency impedance (LFR), i.e., ssf(HFR,LFR).

[0125] The compensation calculation unit is used to obtain the operating condition compensation amount based on the deviation between the current state of the fuel cell stack under dynamic operating conditions and the current state of the fuel cell stack under steady-state operating conditions. The current state of the fuel cell stack under steady-state operating conditions, ssf0(HFR, LFR), is obtained through bench testing and pre-stored in the controller, while the current state of the fuel cell stack under dynamic operating conditions, ssf1(HFR, LFR), is measured online in real time. When calculating this compensation amount, the operating condition compensation amount ΔM is determined by analyzing the deviation of the fuel cell stack state factors between the dynamic operating process (point B) and the steady-state operating process (point S), i.e.:

[0126] ΔM=w1(ΔHFR)+w2(ΔLFR) (17)

[0127] Where w1 and w2 are weighting coefficients determined in advance through sensitivity experiments.

[0128] The second calculation module is used to calculate the compensation coefficient based on the current state of the fuel cell stack under steady-state operating conditions. That is, it calculates the compensation coefficient based on the current state of the fuel cell stack under steady-state operating conditions. This second calculation module includes a first determining unit and a second determining unit.

[0129] The first determining unit is used to determine the stack condition diagnosis result (D,F,S) based on the current state of the stack under steady-state operating conditions.

[0130] The second determining unit is used to determine the compensation coefficient based on the stack condition diagnosis results (D, F, S). (D, F, S) correspond to the following faults in the fuel cell stack: dry, flooding, and starvation, respectively. The compensation coefficients are... Different values ​​are used when different faults occur in the fuel cell stack.

[0131] The correction execution module is used to correct the current operating conditions based on the compensation amount and compensation coefficient of the operating conditions to obtain the optimal control conditions.

[0132] That is, based on the compensation amount and compensation coefficient of the operating conditions, and using a preset calculation method, the current operating conditions are... After correction, the current optimal control conditions are obtained. The specific calculation formula is as follows:

[0133] M1(P air ) = M0(P air )*(1+f air *ΔM) (18)

[0134]

[0135] M1(T) = M0(T) * (1 + f T *ΔM) (20)

[0136] in, The optimal operating conditions at point S under steady-state conditions are given. The optimal operating conditions are those corresponding to operation point B during dynamic operation.

[0137] The control execution module is used to control the vehicle fuel cell according to the optimal control conditions.

[0138] During the operation of the fuel cell system, the stack is controlled according to the above-mentioned optimal control conditions, so that the stack is always in the most suitable working state, reducing the performance loss of each polarization process, reducing the occurrence of irreversible losses, and improving the performance and lifespan of the stack.

[0139] As can be seen from the above technical solution, this embodiment provides a control device for a fuel cell system. This device is applied to the controller of the fuel cell system and specifically calculates the operating condition compensation amount based on the current state of the fuel cell stack under dynamic operating conditions and the current state of the fuel cell stack under steady-state operating conditions; calculates the compensation coefficient based on the current state of the fuel cell stack under steady-state operating conditions; corrects the current operating conditions based on the operating condition compensation amount and the compensation coefficient to obtain the optimal control conditions; and controls the vehicle fuel cell based on the optimal control conditions. This ensures that the fuel cell stack is always in the most suitable operating state, reducing performance losses in various polarization processes and improving the performance and lifespan of the fuel cell stack.

[0140] The units described in the embodiments of this disclosure can be implemented in software or in hardware. The name of a unit does not necessarily limit the unit itself; for example, the first acquisition unit can also be described as "a unit that acquires at least two Internet Protocol addresses".

[0141] The functions described above in this document can be performed, at least in part, by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: Field Programmable Gate Arrays (FPGAs), Application-Specific Integrated Circuits (ASICs), Application Standard Products (ASSPs), System-on-Chip (SoCs), Complex Programmable Logic Devices (CPLDs), and so on.

[0142] Example 3

[0143] refer to Figure 12 The diagram illustrates a suitable structural schematic for implementing the controller in the embodiments of this disclosure. The terminal devices in the embodiments of this disclosure may include, but are not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. The controller in this application is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this disclosure.

[0144] The controller may include a processing device (e.g., a central processing unit, a graphics processing unit, etc.) 601, which can perform various appropriate actions and processes according to a program stored in read-only memory (ROM) 602 or a program loaded from storage device 608 into random access memory (RAM) 603. RAM 603 also stores various programs and data required for the operation of the controller 600. The processing device 601, ROM 602, and RAM 603 are interconnected via bus 604. Input / output (I / O) interface 605 is also connected to bus 604.

[0145] Typically, the following devices can be connected to I / O interface 605: input devices 606 including, for example, a touchscreen, touchpad, keyboard, mouse, camera, microphone, accelerometer, gyroscope, etc.; output devices 607 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 608 including, for example, magnetic tape, hard disk, etc.; and communication devices 609. Communication device 609 allows the controller to communicate wirelessly or wiredly with other devices to exchange data. Although this application shows a controller with various devices, it should be understood that it is not required to implement or have all of the devices shown. More or fewer devices may be implemented alternatively.

[0146] Example 4

[0147] This embodiment provides a computer-readable storage medium carrying one or more computer programs. When these programs are executed by a controller, the controller calculates operating condition compensation amounts based on the current stack state under dynamic and steady-state conditions; calculates compensation coefficients based on the current stack state under steady-state conditions; corrects the current operating conditions based on the compensation amounts and coefficients to obtain optimal control conditions; and controls the vehicle fuel cell based on these optimal control conditions. This ensures the fuel cell stack is always in its most suitable operating state, reducing performance losses in various polarization processes and improving stack performance and lifespan.

[0148] It should be noted that the computer-readable storage medium described above in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0149] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0150] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0151] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0152] The technical solution provided by the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A control method for a fuel cell system, applied to the controller of the fuel cell system, characterized in that, The control method includes the following steps: The operating condition compensation amount is calculated based on the current stack state of the fuel cell system under dynamic operating conditions and the current stack state under steady-state operating conditions. By performing impedance tests at selected frequencies in both the high-frequency and low-frequency regions, the current state of the fuel cell, ssf(HFR,LFR), is obtained, expressed as a fuel cell state factor that includes both the high-frequency impedance (HFR) and the low-frequency impedance (LFR). w1 and w2 are weighting coefficients determined in advance through sensitivity experiments; ∆HFR represents the high-frequency impedance deviation, that is, the difference between the high-frequency impedance HFR1 under dynamic conditions and the high-frequency impedance HFR0 under steady-state conditions; ∆LFR represents the low-frequency impedance deviation, that is, the difference between the low-frequency impedance LFR1 under dynamic conditions and the low-frequency impedance LFR0 under steady-state conditions; the frequency of the high-frequency region is selected close to the frequency at the intersection of the impedance spectrum and the real axis, and the frequency of the low-frequency region is selected in the frequency band where the activation and mass transfer processes work together. Based on the current state of the fuel cell stack under the steady-state operating condition, the fuel cell stack condition diagnosis result (D, F, S) is determined according to the fuel cell stack condition diagnosis logic of the HFR and LFR. The compensation coefficient is then determined based on the fuel cell stack condition diagnosis result (D, F, S). Where D represents membrane dryness, F represents flooding, and S represents undergassing. The compensation coefficient takes different values ​​when different faults occur in the fuel cell stack. Compensation amount based on the operating conditions and the compensation coefficient for the current operating conditions Make corrections to obtain the optimal control conditions. ;in, ; ; ; These are the optimal operating conditions under steady-state conditions. These are the optimal operating conditions during the dynamic operation process. The fuel cell is controlled according to the optimal control conditions.

2. The control method as described in claim 1, characterized in that, The calculation of the operating condition compensation amount based on the current stack state of the fuel cell system under dynamic operating conditions and steady-state operating conditions includes the following steps: Detect the current status of the fuel cell stack in the fuel cell system; The deviation between the current state of the fuel cell stack under the dynamic operating condition and the current state of the fuel cell stack under the steady-state operating condition is calculated to obtain the operating condition compensation amount.

3. A control device for a fuel cell system, applied to the controller of the fuel cell system, characterized in that, The control device includes: The first calculation module is configured to calculate the operating condition compensation amount based on the current stack state of the fuel cell system under dynamic operating conditions and the current stack state under steady-state operating conditions. By performing impedance tests at selected frequencies in both the high-frequency and low-frequency regions, the current state of the fuel cell, ssf(HFR,LFR), is obtained, expressed as a fuel cell state factor that includes both the high-frequency impedance (HFR) and the low-frequency impedance (LFR). w1 and w2 are weighting coefficients determined in advance through sensitivity experiments; ∆HFR represents the high-frequency impedance deviation, that is, the difference between the high-frequency impedance HFR1 under dynamic conditions and the high-frequency impedance HFR0 under steady-state conditions; ∆LFR represents the low-frequency impedance deviation, that is, the difference between the low-frequency impedance LFR1 under dynamic conditions and the low-frequency impedance LFR0 under steady-state conditions; the frequency of the high-frequency region is selected close to the frequency at the intersection of the impedance spectrum and the real axis, and the frequency of the low-frequency region is selected in the frequency band where the activation and mass transfer processes work together. The second calculation module is configured to determine the stack condition diagnosis result (D,F,S) based on the stack condition diagnosis logic of the HFR and LFR according to the current state of the stack under the steady-state operating condition, and to determine the compensation coefficient based on the stack condition diagnosis result (D,F,S). Where D represents membrane dryness, F represents flooding, and S represents undergassing. The compensation coefficient takes different values ​​when different faults occur in the fuel cell stack. The correction execution module is configured to compensate for the amount based on the operating conditions. and the compensation coefficient For current operating conditions Make corrections to obtain the optimal control conditions. ;in, ; ; ; These are the optimal operating conditions under steady-state conditions. These are the optimal operating conditions during the dynamic operation process. The control execution module is configured to control the fuel cell according to the optimal control conditions.

4. The control device as described in claim 3, characterized in that, The first computing module includes: The status detection unit is configured to detect the current status of the fuel cell stack of the fuel cell system; The compensation calculation unit is configured to calculate the deviation between the current state of the fuel cell stack under the dynamic operating condition and the current state of the fuel cell stack under the steady-state operating condition, and obtain the operating condition compensation amount.

5. A controller for use in automotive fuel cells, characterized in that, The controller includes at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs or instructions; The processor is used to execute the computer program or instructions to enable the controller to implement the control method as described in any one of claims 1 to 2.

6. A storage medium used in a controller, characterized in that, The storage medium carries one or more computer programs that can be executed by the controller to enable the controller to implement the control method as described in any one of claims 1 to 2.

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