Decoupling control method and system for fuel cell air intake system

Abstract

The embodiment of the application discloses a kind of decoupling control method and system of fuel cell air intake system.The method comprises: constructing target data model according to the state parameters corresponding to current time and historical time respectively;Determine the first air intake flow and the first air intake pressure of air intake system based on target data model;Determine the demand air intake flow and the demand air intake pressure;According to the difference between the first air intake flow and the demand air intake flow, the difference between the first air intake pressure and the demand air intake pressure, control air intake system.The embodiment of the application determines air intake flow and air intake pressure based on the constructed target data model, and respectively difference value is obtained to control air intake flow and demand air intake flow, and air intake pressure and demand air intake pressure, solve the coupling problem of air intake system, realize the collaborative control of air intake flow and air intake pressure.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fuel cell technology, and in particular to a decoupling control method and system for a fuel cell air intake system. BACKGROUND

[0002] The air intake system of a proton exchange membrane fuel cell is referred to as the life system of the fuel cell, and the performance of the fuel cell stack is ensured by controlling the air intake flow rate and pressure. If the intake amount is too low, the system demand will cause oxygen starvation, thereby causing the voltage of the stack to be too low and affecting the service life of the stack. If the pressure is too high, the operating conditions of the stack will not be met, which will have a fatal impact on the stack. Therefore, the control of the flow rate and pressure of the air intake system is crucial. In the prior art, the control of the air intake system is difficult due to the strong nonlinearity of the air pressure and flow rate, which makes it very difficult to establish a system model. The flow rate and pressure are also strongly coupled, which greatly affects the control effect. At present, most researchers use two controllers to cooperatively control the intake flow rate and pressure. Although this method can convert the nonlinearity problem into a linear problem, it does not address the coupling problem of the flow rate and pressure, resulting in unsatisfactory control effect. SUMMARY

[0003] Therefore, the present application provides a decoupling control method and system for a fuel cell air intake system, which can solve the coupling problem of the air intake system and achieve cooperative control of the air intake flow rate and air intake pressure.

[0004] According to an aspect of the present application, an embodiment of the present application provides a decoupling control method for a fuel cell air intake system, the method comprising:

[0005] constructing a target data model according to the state parameters of the air intake system corresponding to the current time and the historical time;

[0006] determining a first air intake flow rate and a first air intake pressure of the air intake system based on the target data model;

[0007] determining a required air intake flow rate and a required air intake pressure of the air intake system;

[0008] controlling the air intake system according to a first difference between the first air intake flow rate and the required air intake flow rate, and a second difference between the first air intake pressure and the required air intake pressure.

[0009] According to another aspect of the present application, an embodiment of the present application further provides a decoupling control system for a fuel cell air intake system, the system comprising: an air compressor, a motor, a stack, and a throttle,

[0010] The air compressor is connected with the motor and the electric pile, and is used for controlling the rotation speed of the air compressor according to the rotation speed instruction.

[0011] The throttle valve is connected with the electric pile, and is used for controlling the throttle opening value according to the received throttle opening instruction.

[0012] The motor is connected with the air compressor, and is used for driving the rotation speed of the air compressor.

[0013] The electric pile is connected with the air compressor and the throttle valve, and is used for forming the fuel cell.

[0014] According to another aspect of the present application, the present application further provides an electronic device, which comprises:

[0015] at least one processor; and

[0016] a memory connected with the at least one processor in communication; wherein,

[0017] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to execute the decoupling control method of the fuel cell air intake system according to any one of the embodiments of the present application.

[0018] According to another aspect of the present application, the present application further provides a computer readable storage medium, which stores computer instructions for enabling a processor to execute the decoupling control method of the fuel cell air intake system according to any one of the embodiments of the present application when executed by the processor.

[0019] The technical solution of the present application embodiment converts the linear problem between the air compressor and the throttle valve into a nonlinear problem by constructing a target data model, and determines the first air intake flow and the first air intake pressure of the air intake system based on the target data model, so as to control the air intake system according to the difference between the first air intake flow and the required air intake flow, and the difference between the first air intake pressure and the required air intake pressure, solve the coupling problem of the air intake system, and realize the collaborative control of the air intake flow and the air intake pressure.

[0020] It should be understood that the contents described in this part are not intended to identify the key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to make the technical solution in the embodiments of the present application clearer, the accompanying drawings needed in the embodiments will be briefly introduced. Obviously, the accompanying drawings in the following description only represent some of the embodiments of the present application, and all other drawings obtained by those skilled in the art without any creative effort should belong to the protection scope of the present application.

[0022] Figure 1 A flow chart of a decoupling control method of a fuel cell air intake system according to an embodiment of the present application is provided.

[0023] Figure 2 A flow chart of another decoupling control method of a fuel cell air intake system according to an embodiment of the present application is provided.

[0024] Figure 3 A decoupling control flowchart of a fuel cell air intake system according to an embodiment of the present application is provided.

[0025] Figure 4 A flow chart of another decoupling control method of a fuel cell air intake system according to an embodiment of the present application is provided.

[0026] Figure 5 A structure block diagram of a decoupling control system of a fuel cell air intake system according to an embodiment of the present application is provided.

[0027] Figure 6 A structure block diagram of another decoupling control system of a fuel cell air intake system according to an embodiment of the present application is provided. DETAILED DESCRIPTION

[0028] In order to make the technical solution in the embodiments of the present application clearer, the accompanying drawings needed in the embodiments will be briefly introduced. Obviously, the accompanying drawings in the following description only represent some of the embodiments of the present application, and all other drawings obtained by those skilled in the art without any creative effort should belong to the protection scope of the present application.

[0029] It is to be understood that the terminology "first", "second" and the like used in the specification and the claims of the application as well as the appended drawings is merely used for distinguishing between similar objects and does not necessarily imply a particular order or chronology. It is to be understood that the use of the term "act" in the description and the claims of the application does not limit the action to a single step, but that the act can comprise a plurality of steps. It is to be understood that the use of the term "including" does not limit the mentioned steps to the precise steps of the described embodiments. It is to be understood that the inclusion of a step does not preclude the inclusion of yet a further step or steps.

[0030] In an embodiment, Figure 1 A flow chart of a decoupling control method of a fuel cell air intake system is provided for an embodiment of the application, which can be applicable to the case of decoupling control of air flow and air intake pressure of the fuel cell air intake system.

[0031] As Figure 1 shown, the method comprises the following specific steps:

[0032] S110, constructing a target data model according to the state parameters of the air intake system corresponding to the current time and the historical time respectively.

[0033] The historical time can be understood as each time before the current time. The state parameters refer to the input parameters and output parameters corresponding to the air intake system. Of course, the state parameters can include but are not limited to: air machine speed value, throttle opening value, air intake flow and air intake pressure. The target data model can be understood as a data model constructed according to the relevant state parameters of the air intake system.

[0034] In this embodiment, the first state parameters corresponding to the current time and the historical time, and the second state parameters corresponding to the current time and the historical time can be used as inputs in a data-driven manner, and the air intake flow and the air intake pressure of the next time can be used as outputs to construct a first data model. Under certain conditions, the first data model is converted to obtain a target data model; in some embodiments, the air compressor system modeling, the intake manifold model, the cathode model and the throttle model can also be established by the positive correlation between the outlet flow of the compressor and its speed and the negative correlation between the outlet flow of the compressor and its compression ratio, and the air compressor system modeling, the intake manifold model, the cathode model and the throttle model are combined to form a target data model; in other embodiments, a mathematical model can also be established by other means, which is not limited in this embodiment.

[0035] S120, determine the first air intake flow and the first air intake pressure of the air intake system based on the target data model.

[0036] The first air intake flow can be understood as the actual air intake flow obtained by the target data model. The first air intake pressure can be understood as the actual air intake pressure obtained by the target data model.

[0037] In this embodiment, the parameter estimation value corresponding to the time-varying parameter matrix in the target data model can be determined according to a preset first criterion function, and the target air compressor speed value and the target throttle opening value at the current time can be determined according to a preset second criterion function, the target data model and the reference estimation value, and the target air compressor speed value is taken as the first air intake flow and the target throttle opening value is taken as the first air intake pressure. In some embodiments, the expected air mass flow and the expected fuel cell cathode pressure can also be preprocessed to obtain the expected volume flow and the expected pressure ratio. The expected volume flow is subtracted from the actual volume flow to obtain a volume flow error. The expected pressure ratio is subtracted from the actual pressure ratio to obtain a pressure ratio error. The volume flow error and the pressure ratio error are input into different controllers to obtain the control amount corresponding to the controller. The control amount is input into the decoupling controller to obtain the air intake flow and the air intake pressure.

[0038] S130, determine the required air intake flow and the required air intake pressure of the air intake system.

[0039] The required air intake flow refers to the air intake flow required by the air intake system, and the required air intake pressure refers to the intake pressure required by the air intake system.

[0040] In this embodiment, the required power of the air intake system can be determined, and the required air intake flow and the required air intake pressure of the air intake system can be determined according to the required power. In some embodiments, the required air intake flow and the required air intake pressure of the air intake system corresponding to the required power can be found in a pre-stored table by reading the table. In addition, the required air intake flow and the required air intake pressure of the air intake system can also be determined by other methods, which are not limited in this embodiment.

[0041] S140, control the air intake system according to the first difference between the first air intake flow and the required air intake flow, and the second difference between the first air intake pressure and the required air intake pressure.

[0042] The first difference value refers to a flow difference value between the first air intake flow and a required air intake flow. The second difference value refers to an air intake difference value between the first air intake pressure and a required air intake pressure. It should be noted that the first difference value and the second difference value can determine whether the current air intake system meets the control requirement.

[0043] In the embodiment, the absolute values of the first air intake flow and the required air intake flow are subtracted to obtain the first difference value, and the absolute values of the first air intake pressure and the required air intake pressure are subtracted to obtain the required difference value. In the case that the first difference value and the required difference value are both 0, it is determined that the first air intake flow and the first air intake pressure meet the requirement of the air intake system. The air compressor is controlled by the first air intake flow, and the throttle is controlled by the first air intake pressure, so as to control the air intake system. In the case that any one of the first difference value and the required difference value is 0, the steps of subtracting the absolute values of the first air intake flow and the required air intake flow and subtracting the absolute values of the first air intake pressure and the required air intake pressure are returned until the first difference value and the required difference value are both 0. In some embodiments, the air intake flow control quantity and the air intake pressure control quantity can be directly input into the decoupling controller, and the air intake flow and the air intake pressure can be directly calculated by the decoupling controller. The air compressor is controlled by the air intake flow, and the throttle is controlled by the air intake pressure, so as to control the air intake system.

[0044] The technical scheme of the embodiment of the application converts the linear problem between the air compressor and the throttle into a nonlinear problem by constructing a target data model, and determines the first air intake flow and the first air intake pressure of the air intake system based on the target data model. The air intake system is controlled according to the corresponding difference values of the first air intake flow and the required air intake flow, and the first air intake pressure and the required air intake pressure, so as to solve the coupling problem of the air intake system and realize the collaborative control of the air intake flow and the air intake pressure.

[0045] In an embodiment, Figure 2 The flowchart of another decoupling control method of the fuel cell air intake system provided by the embodiment of the application is further refined based on the above-mentioned embodiments. The target data model is constructed according to the state parameters of the air intake system corresponding to the current time and the historical time, the first air intake flow and the first air intake pressure of the air intake system are determined based on the target data model, the required air intake flow and the required air intake pressure of the air intake system are determined, and the air intake system is controlled according to the first difference value between the first air intake flow and the required air intake flow, and the second difference value between the first air intake pressure and the required air intake pressure.

[0046] like Figure 2 As shown, the decoupling control method for the fuel cell air intake system in this embodiment may specifically include the following steps:

[0047] S210. Take the first state parameters corresponding to the current time and the historical time, and the second state parameters corresponding to the current time and the historical time, as inputs, and take the air intake flow rate and air intake pressure of the next time as outputs to construct the first data model.

[0048] The first state parameters include: engine speed and throttle opening; the second state parameters include: air intake flow rate and air intake pressure; the first data model is a multiple-input multiple-output (MIMO) data model. The next moment can be understood as moment k+1, which is the moment following moment k.

[0049] In this embodiment, the engine speed and throttle opening values ​​corresponding to the current and historical times, respectively, as well as the air intake flow rate and air intake pressure corresponding to the current and historical times, are used as inputs to construct the first data model, and the air intake flow rate and air intake pressure at the next time moment are used as outputs. In one embodiment, considering a system with two inputs and two outputs, the first data model can be expressed by the formula y(k+1)=f(y(k),…,y(kn)). a ), u(k), ..., u(kn) b ), where k represents the current time, k+1 represents the next time, f(y(k), ..., y(kn) a ), u(k), ..., u(kn) b T(...) is a nonlinear function. y(k+1) represents the air intake flow rate and air intake pressure at time k+1; y(k) = [W ca P ca ] T Let W represent the output air intake flow rate and air intake pressure at time k, where W ca P represents the air intake flow rate. ca Represents the air intake pressure; u(k) = [N] cmd θ cmd ] T This represents the transpose of the matrix consisting of the output air compressor speed and throttle opening at time k, where N cmd Indicates the air compressor speed and θ cmd Throttle opening value; n a ,n b They are constants.

[0050] S220. If the Lipschitz condition is met and the difference between the air compressor speed and throttle opening values ​​corresponding to the current time and the previous time is not 0, the first data model is converted into the second data model, and the second data model is used as the target data model.

[0051] The target data model is a compact-format dynamically linearized data model. The previous time step refers to time step k-1, which is time step k.

[0052] In this embodiment, if the Lipschitz condition is satisfied and the difference between the air compressor speed and throttle opening values ​​corresponding to the current and previous times is not zero, the first data model can be converted into a second data model, and the second data model can be used as the target data model. Specifically, when f(y(k), ..., y(kn) in the two-input two-output system... a ), u(k), ..., u(kn) b Regarding the nth a The variables of +2 have continuous partial derivatives and the system satisfies the Lipschitz condition. Furthermore, when Δ‖u(k)‖≠0, there exists a time-varying parameter Γ(k) of the pseudo-Jacobi matrix (PJM). The first data model can be represented as a compact-format dynamic linearization (CFDL) data model, which is the target data model, expressed by the formula Δy(k+1)=Γ(k)Δu(k), where Γ(k) is the time-varying parameter matrix, expressed by the formula... Among them, Υ 11 (k), Υ 12 (k), Υ 21 (k) and Υ 22 (k) represents the time-varying parameters; Δy(k+1) represents the difference between y(k+1) and y(k), where y(k) represents the output air intake flow rate and air intake pressure at time k, and y(k+1) represents the output air intake flow rate and air intake pressure at time k+1; Δu(k) represents the difference between u(k) and u(k-1), where u(k) represents the output air compressor speed and throttle opening at time k, and u(k) represents the output air compressor speed and throttle opening at time k-1.

[0053] S230. Determine the parameter estimates corresponding to the time-varying parameter matrix in the target data model based on the preset first criterion function.

[0054] The preset first criterion function can also be called the parameter estimation criterion function. The parameter estimate refers to the parameter estimate corresponding to the time-varying parameter matrix.

[0055] In this embodiment, the parameter estimates corresponding to the time-varying parameter matrix in the target data model can be determined based on a preset first criterion function. Specifically, there are two ways to determine the parameter estimates corresponding to the time-varying parameter matrix in the target data model: one is to use an improved projection algorithm to determine the first parameter estimate corresponding to the time-varying parameter matrix in the preset first criterion function; the other is to use a preset pseudo-partial derivative identification algorithm to identify the time-varying parameter matrix in the preset first criterion function to obtain the second parameter estimate. It should be noted that since solving for the first parameter estimate using the improved projection algorithm involves the step of finding the matrix inverse, which is relatively time-consuming, the preset pseudo-partial derivative identification algorithm is generally chosen to identify the time-varying parameter matrix in the preset first criterion function to obtain the second parameter estimate.

[0056] In one embodiment, a preset first criterion function is established based on the fact that the modulus difference between the estimated parameter value and the actual parameter value is less than a first preset difference. The estimated parameter value corresponding to the time-varying parameter matrix in the target data model is determined according to the preset first criterion function, including at least one of the following:

[0057] An improved projection algorithm is used to determine the estimated value of the first parameter corresponding to the time-varying parameter matrix in the preset first criterion function;

[0058] A preset pseudo-partial derivative identification algorithm is used to identify the time-varying parameter matrix in the preset first criterion function in order to obtain the first parameter estimate.

[0059] In this embodiment, the preset first criterion function is established by ensuring that the magnitude difference between the estimated parameter value and the actual parameter value is less than a first preset difference. An improved projection algorithm can be used to determine the first parameter estimate corresponding to the time-varying parameter matrix in the preset first criterion function. In this embodiment, the preset first criterion function can be expressed by the formula: Where μ > 0 is a weighting parameter used to control the estimated value from changing significantly, Δy(k) represents the difference between y(k) and y(k-1), and Δu(k-1) represents the difference between u(k-1) and u(k-2).

[0060] In this embodiment, the estimated value of the first parameter can be expressed by the formula: Where Δy(k) represents the difference between y(k) and y(k-1), y(k) represents the output air intake flow rate and air intake pressure at time k, y(k+1) represents the output air intake flow rate and air intake pressure at time k+1, Δu(k-1) represents the difference between u(k-1) and u(k-2), u(k-1) represents the output air compressor speed and throttle opening at time k-1, u(k-2) represents the output air compressor speed and throttle opening at time k-2, and μ∈(0,2] is the step size factor. Let I be the estimated value of Γ(k), and let I denote the identity matrix.

[0061] S240. Based on the preset second criterion function, target data model and reference estimate, determine the target air compressor speed and target throttle opening value at the current moment, and use the target air compressor speed as the first air intake flow rate and the target throttle opening value as the first air intake pressure.

[0062] The preset second criterion function can also be called the air intake pressure and flow rate criterion function.

[0063] In this embodiment, the target air compressor speed and target throttle opening value at the current moment can be determined based on a preset second criterion function, a target data model, and a reference estimate. The target air compressor speed is used as the first air intake flow rate, and the target throttle opening value is used as the first air intake pressure. Specifically, the output of the target data model can be substituted into the preset second criterion function as the expected output pressure and flow rate to obtain the first function corresponding to the first air compressor speed and first throttle opening value at the current moment. The reference estimate value is substituted into the first function as the actual value of the time-varying parameter to obtain the target control function, and the target air compressor speed and target throttle opening value are output through the target control function.

[0064] In one embodiment, determining the target air compressor speed and target throttle opening value at the current moment based on a preset second criterion function, a target data model, and a reference estimate includes:

[0065] The pressure and flow rate of the target data model are substituted into the preset second criterion function as the expected output of the target data model, and the first function corresponding to the first air compressor speed value and the first throttle opening value at the current moment is obtained.

[0066] The reference estimated value is substituted into the actual value of the time-varying parameter in the first function to obtain the target control function, and the target air compressor speed value and target throttle opening value are output through the target control function.

[0067] The target control function refers to the control function that determines the target air compressor speed and the target throttle opening value.

[0068] In this embodiment, the preset second criterion function is established based on the fact that the modulus difference between the expected output value and the actual output value is less than a second preset difference and the deviation of the control input does not exceed a preset deviation; the preset second criterion function is expressed by the formula J(u(k))=||y * (k+1)-y(k+1)|| 2 +λ||u(k)-u(k-1)|| 2Where λ > 0 is the weight parameter, y * (k+1)=[W ca,ref P ca,ref ] T Let y(k+1) represent the desired output air intake pressure and air intake flow rate, y(k+1) represent the output air intake flow rate and air intake pressure at time k+1, u(k) represent the output air compressor speed and throttle opening at time k, and u(k-1) represent the output air compressor speed and throttle opening at time k-1.

[0069] In this embodiment, the output of the target data model can be substituted into the preset second criterion function as the expected output pressure and flow rate, to obtain the first function corresponding to the first air compressor speed and the first throttle opening value at the current moment. The reference estimated value is substituted into the first function as the actual value of the time-varying parameter, to obtain the target control function, and the target air compressor speed and target throttle opening value are output through the target control function. Specifically, by substituting the output of the target data model as the expected output pressure and flow rate of the preset second criterion function and differentiating it with respect to u(k), and setting the expression equal to zero, it can be seen that the first function can be expressed as: u(k)=u(k-1)+(λI+Γ) T (k)Γ(k)) -1 Γ T (k)(y * (k+1)-y(k)), where λ>0 is the weight parameter, y * (k+1)=[W ca,ref P ca,ref ] T Let Γ(k) represent the desired output air intake pressure and air intake flow rate, y(k) represent the output air intake flow rate and air intake pressure at time k, Γ(k) be the time-varying parameter matrix, and u(k-1) represent the output air compressor speed and throttle opening at time k-1.

[0070] In one embodiment, the target control function is expressed by the formula: Where α is the step size factor, α∈(0,1], u(k)=[N cmd θ cmd ] T , representing the output air compressor speed and throttle opening at time k, where N cmd θ represents the air compressor speed. cmd This is represented as the throttle opening value; λ > 0 is the weighting parameter, y * (k+1)=[W ca,ref P ca,ref ] TThe desired output air intake pressure and air intake flow rate; This represents the transpose of the matrix corresponding to the parameter estimates at time k; Let y(k) represent the square of the parameter estimate modulus, y(k) represent the output air intake flow rate and air intake pressure at time k, and u(k-1) represent the output air compressor speed and throttle opening at time k-1.

[0071] S250: Obtain the required power for the air intake system.

[0072] In this embodiment, the required power of the air intake system can be obtained, so as to determine the required air intake flow rate and required air intake pressure of the air intake system based on the required power.

[0073] It should be noted that the execution order of S250 and S210 can be understood as follows: the first air intake flow rate and the first air intake pressure of the air intake system can be determined first based on the target data model, and then the required air intake flow rate and the required air intake pressure of the air intake system can be determined; or the required air intake flow rate and the required air intake pressure of the air intake system can be determined first, and then the first air intake flow rate and the first air intake pressure of the air intake system can be determined based on the target data model.

[0074] S260. Read the pre-stored MAP table; wherein, the MAP table stores a set of data in the form of key-value pairs, with the required power as the key and the corresponding value as the value.

[0075] In this embodiment, a pre-stored MAP table is read; wherein, the MAP table stores a set of data in the form of key-value pairs, with the required power as the key and the corresponding value as the value. It should be noted that, in this embodiment, the values ​​corresponding to the required power are the required air intake flow rate and required air intake pressure of the air intake system, and each required power corresponds to the corresponding required air intake flow rate and required air intake pressure of the air intake system.

[0076] S270. Find the required air intake flow rate and required air intake pressure of the air intake system corresponding to the required power in the MAP table.

[0077] In this embodiment, the required air intake flow rate and required air intake pressure of the air intake system corresponding to the required power can be found in the MAP table by traversing or matching.

[0078] S280, the absolute values ​​of the first air intake flow rate and the required air intake flow rate are calculated to obtain the first difference value, and the absolute values ​​of the first air intake pressure and the required air intake pressure are calculated to obtain the required difference value.

[0079] In this embodiment, the absolute values ​​of the first air intake flow rate and the required air intake flow rate can be differed to obtain the first difference value, and it can be determined whether the first difference value is 0. The absolute values ​​of the first air intake pressure and the required air intake pressure can be differed to obtain the required difference value, and it can be determined whether the second difference value is 0.

[0080] S290. Determine whether the first difference and the demand difference are both 0; if yes, execute S2100; if no, execute S210.

[0081] In this embodiment, it is determined whether both the first difference and the demand difference are 0. If both the first difference and the demand difference are 0, it is determined that the first air intake flow rate and the first air intake pressure meet the requirements of the air intake system. The air compressor is controlled by the first air intake flow rate, and the throttle valve is controlled by the first air intake pressure to control the air intake system. If either the first difference or the demand difference is not 0, the process returns to the step of constructing a target data model to determine the first air intake flow rate and the first air intake pressure through the target data model.

[0082] S2100: Determine the first air intake flow rate and the first air intake pressure to meet the needs of the air intake system. Control the air compressor through the first air intake flow rate and control the throttle valve through the first air intake pressure to control the air intake system.

[0083] In this embodiment, if both the first difference and the demand difference are 0, it is determined that the first air intake flow rate and the first air intake pressure meet the demand of the air intake system. The air compressor is controlled by the first air intake flow rate, and the throttle valve is controlled by the first air intake pressure to control the air intake system.

[0084] The technical solution of this invention constructs a first data model by taking the first state parameters corresponding to the current time and the historical time, and the second state parameters corresponding to the current time and the historical time, as inputs, and taking the air intake flow rate and air intake pressure at the next time as outputs. Under the condition that the Lipschitz condition is met and the difference between the air compressor speed and throttle opening values ​​corresponding to the current time and the previous time is not zero, the first data model is converted into a second data model, which is then used as the target data model. This transforms the linear problem between the air compressor and the throttle into a nonlinear problem. The estimated parameter values ​​corresponding to the time-varying parameter matrix in the target data model are determined by a preset first criterion function. Based on the preset second criterion function, the target data model, and the reference estimated values, the target air compressor speed and target throttle opening values ​​at the current time are determined. The required air intake flow rate and required air intake pressure of the air intake system corresponding to the required power are found in the MAP table. Whether the control is satisfied is determined based on whether the first difference and the required difference are both zero. This further solves the coupling problem of the air intake system and achieves coordinated control of air intake flow rate and air intake pressure.

[0085] In one embodiment, to facilitate a better understanding of the decoupling control flowchart of the fuel cell air intake system, Figure 3 This is a schematic diagram of the decoupled control process of a fuel cell air intake system provided in an embodiment of the present invention. Since there is no order between determining the first air intake flow rate and the first air intake pressure of the air intake system based on the target data model and determining the required air intake flow rate and the required air intake pressure of the air intake system, in this embodiment of the present invention, the control of the fuel cell air intake system is further explained by taking the determination of the required air intake flow rate and the required air intake pressure of the air intake system as an example.

[0086] like Figure 3 As shown, the specific steps of the decoupling control process of the fuel cell air intake system are as follows:

[0087] S310, Obtain the required power for the air intake system.

[0088] S320. Determine the required air intake flow rate and required air intake pressure of the air intake system based on the required power.

[0089] S330. Determine the first air intake flow rate and the first air intake pressure of the air intake system based on the target data model.

[0090] S340. The first difference value is obtained by calculating the difference between the absolute values ​​of the first air intake flow rate and the required air intake flow rate, and the demand difference value is obtained by calculating the difference between the absolute values ​​of the first air intake pressure and the required air intake pressure.

[0091] S350. Determine if both the first difference and the required difference are 0; if yes, proceed to S360; otherwise, return to S330.

[0092] S360: Determine the required air intake flow rate and required air intake pressure to meet the needs of the air intake system. Control the air compressor by controlling the required air intake flow rate and control the throttle valve by controlling the required air intake pressure to control the air intake system.

[0093] In one embodiment, to facilitate a better understanding of the decoupled control block diagram of the fuel cell air intake system, Figure 4 This is a schematic diagram of the decoupling control process of another fuel cell air intake system provided in an embodiment of the present invention. Figure 4 W in ca,ref P ca,ref N represents the desired output air intake pressure and air intake flow rate, respectively. cmd θ represents the air compressor speed. cmd Represented as throttle opening value, W ca P ca These represent the final output air intake pressure and air intake flow rate, respectively. The parameter estimation criterion function is the preset first criterion function in the above embodiment.

[0094] In this embodiment, the required power of the air intake system is first determined. Based on the required power, the required air intake flow rate and required air intake pressure of the air intake system are determined. Then, the time-varying parameter matrix in the target data model is determined, and a time-varying parameter estimation criterion function is constructed. A preset pseudo-partial derivative identification algorithm is used to identify the time-varying parameter matrix in the time-varying parameter estimation criterion function to obtain parameter estimates. The reference estimates are substituted into the first function as the actual values ​​of the time-varying parameters to obtain the target control function. The target air compressor speed and target throttle opening value are output through the target control function. The air intake system is controlled based on the first difference between the target air intake flow rate and the required air intake flow rate, and the demand difference between the target air intake pressure and the required air intake pressure.

[0095] In one embodiment, Figure 5 The present invention provides a structural block diagram of a decoupling control system for a fuel cell air intake system, the system comprising: an air compressor 510, a motor 520, a fuel cell stack 530, and a throttle valve 540;

[0096] The air compressor 510 is connected to the motor 520 and the fuel cell stack 530 respectively, and is used to control the speed of the air compressor according to the speed command.

[0097] Throttle valve 540 is connected to fuel cell stack 530 and is used to control throttle valve opening value according to the received throttle valve opening command;

[0098] Motor 520 is connected to air compressor 510 and is used to drive the air compressor 510 to rotate.

[0099] The fuel cell stack 530 is connected to the air compressor 510 and the throttle valve 540 to form a fuel cell.

[0100] In one embodiment, Figure 6 The present invention provides a structural block diagram of a decoupling control system for a fuel cell air intake system according to an embodiment of the present invention. The system includes: a 610 air compressor, a 620 motor, a 630 fuel cell stack, a 640 intercooler, and a 650 throttle valve.

[0101] Among them, the 610 air compressor is connected to the 620 motor and the 630 fuel cell stack, and is used to control the speed of the air compressor according to the speed command;

[0102] The 650 throttle valve is connected to the 630 fuel cell stack and is used to control the throttle valve opening value according to the received throttle valve opening command;

[0103] The 620 motor is connected to the 610 air compressor to drive the air compressor's speed.

[0104] The 630 fuel cell stack is connected to the 610 air compressor and the 650 throttle valve to form a fuel cell;

[0105] The 640 intercooler is connected to the 630 fuel cell stack and the 610 air compressor to reduce the engine's intake air temperature.

[0106] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0107] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A decoupling control method for a fuel cell air intake system, characterized in that, include: Construct a target data model based on the state parameters of the air intake system at the current and historical times respectively; Based on the target data model, determine the first air intake flow rate and the first air intake pressure of the air intake system; Determine the required air intake flow rate and required air intake pressure of the air intake system; The air intake system is controlled based on a first difference between the first air intake flow rate and the required air intake flow rate, and a second difference between the first air intake pressure and the required air intake pressure. The step of constructing the target data model based on the state parameters of the air intake system corresponding to the current time and historical time respectively includes: The first data model is constructed by taking the first state parameters corresponding to the current time and the historical time, and the second state parameters corresponding to the current time and the historical time, as inputs, and taking the air intake flow rate and air intake pressure of the next time as outputs; wherein, the first state parameters include: air engine speed value and throttle opening value; the second state parameters include: air intake flow rate and air intake pressure; the first data model is a multi-input multi-output data model; If the Lipschitz condition is satisfied and the difference between the air compressor speed and throttle opening values ​​corresponding to the current time and the previous time is not zero, the first data model is converted into a second data model, and the second data model is used as the target data model; wherein, the target data model is a compact form dynamically linearized data model; The first data model is expressed by the formula y(k+1)=f(y(k),…,y(kn)). a ),u(k),…,u(kn b ), where y(k+1) represents the air intake flow rate and air intake pressure output at time k+1; y(k) = [W ca P ca ] T Let W represent the output air intake flow rate and air intake pressure at time k, where W ca P represents the air intake flow rate. ca Represents the air intake pressure; u(k) = [N] cmd θ cmd ] T This represents the transpose of the matrix consisting of the output air compressor speed and throttle opening at time k, where N cmd Indicates the air compressor speed and θ cmd Throttle opening value; n a ,n b They are constants; The target data model is expressed by the formula Δy(k+1)=Γ(k)Δu(k), where Γ(k) is the time-varying parameter matrix, expressed by the formula... Among them, Υ 11 (k), Υ 12 (k), Υ 21 (k) and Υ 22 (k) represents the time-varying parameters; Δy(k+1) represents the difference between y(k+1) and y(k), where y(k) represents the output air intake flow rate and air intake pressure at time k, y(k+1) represents the output air intake flow rate and air intake pressure at time k+1, Δu(k) represents the difference between u(k) and u(k-1), where u(k) represents the output air compressor speed and throttle opening at time k, and u(k-1) represents the output air compressor speed and throttle opening at time k-1.

2. The method according to claim 1, characterized in that, The step of determining the first air intake flow rate and the first air intake pressure of the air intake system based on the target data model includes: The parameter estimates corresponding to the time-varying parameter matrix in the target data model are determined based on a preset first criterion function. Based on the preset second criterion function, the target data model, and the parameter estimate, the target air compressor speed and the target throttle opening value at the current moment are determined, and the target air compressor speed is used as the first air intake flow rate, and the target throttle opening value is used as the first air intake pressure.

3. The method according to claim 2, characterized in that, The preset first criterion function is established when the modulus difference between the parameter estimate and the actual parameter value is less than a first preset difference. Determining the parameter estimate corresponding to the time-varying parameter matrix in the target data model based on the preset first criterion function includes at least one of the following: An improved projection algorithm is used to determine the estimated value of the first parameter corresponding to the time-varying parameter matrix in the preset first criterion function; A preset pseudo-partial derivative identification algorithm is used to identify the time-varying parameter matrix in the preset first criterion function to obtain the second parameter estimate.

4. The method according to claim 2, characterized in that, The preset second criterion function is established based on the fact that the magnitude difference between the expected output value and the actual output value is less than a second preset difference and the deviation of the control input does not exceed a preset deviation; the preset second criterion function is expressed by the formula: Where λ>0 is the weight parameter, y * (k+1)=[W ca,ref P ca,ref ] T This is expressed as the desired output air intake pressure and air intake flow rate; the determination of the target air compressor speed and target throttle opening value at the current moment based on the preset second criterion function, the target data model, and the parameter estimate includes: The pressure and flow rate of the target data model are substituted into the preset second criterion function as the expected output of the target data model to obtain the first function corresponding to the first air compressor speed value and the first throttle opening value at the current moment. The estimated parameter value is substituted into the first function as the actual value of the time-varying parameter to obtain the target control function, and the target air compressor speed value and the target throttle opening value are output through the target control function.

5. The method according to claim 4, characterized in that, The target control function is expressed by the formula: Where α is the step size factor, α∈(0,1], u(k)=[N cmd θ cmd ] T , representing the output air compressor speed and throttle opening at time k, N cmd θ represents the air compressor speed. cmd This is represented as the throttle opening value; λ > 0 is the weighting parameter, y * (k+1)=[W ca,ref P ca,ref ] T The desired output air intake pressure and air intake flow rate; This represents the transpose of the matrix corresponding to the parameter estimates at time k; Let y(k) represent the square of the parameter estimate modulus, y(k) represent the output air intake flow rate and air intake pressure at time k, and u(k-1) represent the output air compressor speed and throttle opening at time k-1.

6. The method according to claim 1, characterized in that, Determining the required air intake flow rate and required air intake pressure of the air intake system includes: Obtain the required power of the air intake system; Read the pre-stored MAP table; wherein, the MAP table stores a set of data in the form of key-value pairs, where the required power is the key and the value corresponding to the required power is the value; Find the required air intake flow rate and required air intake pressure of the air intake system corresponding to the required power in the MAP table.

7. The method according to claim 1, characterized in that, The step of controlling the air intake system based on a first difference between the first air intake flow rate and the required air intake flow rate, and a demand difference between the first air intake pressure and the required air intake pressure, includes: The first difference value is obtained by taking the difference between the absolute values ​​of the first air intake flow rate and the required air intake flow rate, and the required difference value is obtained by taking the difference between the absolute values ​​of the first air intake pressure and the required air intake pressure. Determine whether both the first difference and the demand difference are 0; If so, the first air intake flow rate and the first air intake pressure are determined to meet the requirements of the air intake system. The air compressor is controlled by the first air intake flow rate, and the throttle valve is controlled by the first air intake pressure to control the air intake system. If not, return to the steps of calculating the difference between the absolute values ​​of the first air intake flow rate and the required air intake flow rate, and the difference between the absolute values ​​of the first air intake pressure and the required air intake pressure, until both the first difference and the required difference are 0.

8. A decoupling control system for a fuel cell air intake system, characterized in that, A decoupling control method applied to a fuel cell air intake system as described in any one of claims 1-7, wherein the system comprises: an air compressor, a motor, a fuel cell stack, and a throttle valve; The air compressor is connected to the motor and the fuel cell stack, and is used to control the speed of the air compressor according to the speed command; The throttle valve is connected to the fuel cell stack and is used to control the throttle valve opening value according to the received throttle valve opening command; The motor is connected to the air compressor and is used to drive the air compressor to rotate. The fuel cell stack is connected to the air compressor and the throttle valve to form a fuel cell.

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