Fuel cell variable altitude power optimization method and system considering intercooler energy consumption

Abstract

The present application relates to the technical field of fuel cell system control, and discloses a fuel cell variable altitude power optimization method and system considering the energy consumption of an intercooler, which comprises the following steps: establishing a fuel cell stack model, a cathode air supply system model and an atmospheric environment parameter model; establishing an intercooler heat load model considering altitude changes, and incorporating the heat dissipation power consumption of the intercooler into the calculation of the net power of the fuel cell system; constructing a four-dimensional mapping relationship of load current-supply parameter-stack performance-parasitic power, and solving the optimal supply parameters under different altitudes and load currents with the maximum net power of the fuel cell system as the target; and designing a hierarchical disturbance observer method, and using the optimal supply parameters as the feedforward value to correct the working voltage of the air compressor and the opening degree of the back pressure valve online. The present application incorporates the heat dissipation power consumption of the intercooler into the optimization target of the net power of the system, adopts a hierarchical architecture of "offline calibration + online correction", and effectively improves the net output power of the fuel cell system under variable altitude conditions.

Description

Technical Field

[0001] This invention relates to the field of fuel cell system control technology, and in particular to a method and system for optimizing fuel cell power at varying altitudes, taking into account intercooler energy consumption. Background Technology

[0002] In recent years, fuel cell vehicles have become an important technological path for electrification in the transportation sector due to their high efficiency and cleanliness. However, the power degradation problem of fuel cell systems in varying altitude environments has limited their large-scale application in high-altitude transportation. Existing technologies have proposed solutions to the power optimization problem of fuel cells in varying altitude environments. For example, Chinese invention application CN117154149A discloses a real-time power optimization method for fuel cell systems in varying altitudes. This method combines particle swarm optimization algorithm feedforward with perturbation-observation, using the air compressor operating voltage as the optimization variable to achieve real-time optimization of the net power of the fuel cell system under varying altitude conditions. However, its optimization objective only considers the air compressor power consumption and does not fully consider the changes in intercooler heat dissipation power consumption under varying altitude environments. Furthermore, the optimization variable in this patent is the air compressor operating voltage, and the back pressure valve opening is set to a constant value.

[0003] In fact, the increased compression ratio of the air compressor in high-altitude, low-pressure environments leads to a sharp rise in its outlet temperature, exceeding the thermal stability threshold of the proton exchange membrane. To prevent high-temperature air from causing membrane electrode performance degradation, the cathode air supply system must utilize an intercooler to cool the incoming air. The intercooler's heat dissipation requirements increase significantly with altitude, and its heat dissipation power consumption (including the power consumption of the circulating water pump and cooling fan) as a proportion of the system's net power also increases. Ignoring this power consumption will lead to errors in the calculation of the system's net power, thus affecting the effectiveness of the power optimization strategy. Furthermore, traditional single-variable optimization structures cannot simultaneously account for the coupled effects of oxygen ratio and cathode pressure; while purely offline optimization methods cannot meet real-time requirements due to high computational complexity and difficulty in covering all operating conditions. Summary of the Invention

[0004] The purpose of this invention is to solve the problems in the prior art.

[0005] The technical solution adopted by this invention to solve its technical problem is: to provide a method for optimizing the power of a fuel cell at varying altitudes, considering the energy consumption of the intercooler, comprising the following steps:

[0006] Establish fuel cell stack models, cathode air supply system models, and atmospheric environmental parameter models;

[0007] Establish a heat load model for the intercooler that takes into account altitude changes, quantify the impact of the increase in air compressor outlet air temperature under altitude gradient on the heat dissipation power consumption of the intercooler, and incorporate the heat dissipation power consumption of the intercooler into the net power calculation of the fuel cell system.

[0008] A four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power is constructed. With the goal of maximizing the net power of the fuel cell system, a global optimization algorithm is used to solve for the optimal gas supply parameters under different altitudes and load currents, including the air compressor operating voltage and back pressure valve opening.

[0009] The design incorporates a hierarchical perturbation observation method that optimizes the main and auxiliary cycles for oxygen ratio and cathode pressure. An adaptive perturbation step size mechanism is introduced to use the optimal air supply parameters as feedforward values ​​to correct the air compressor operating voltage and back pressure valve opening online.

[0010] When a change in load current or altitude parameter is detected, the feedforward value is recalled and the hierarchical disturbance observation optimization process is restarted until the maximum net system power point under the current operating condition is tracked.

[0011] Preferably, the establishment of the fuel cell stack model and the cathode air supply system model includes:

[0012] An electric stack model was established based on electrochemical principles, including open-circuit voltage, activation polarization voltage, ohmic polarization voltage, and concentration polarization voltage.

[0013] Establish a model of the cathode air supply system, including an air compressor model, a cathode supply manifold model, a cathode flow channel model, and an exhaust manifold model;

[0014] An atmospheric environmental parameter model was established based on the international standard atmospheric model to reflect the relationship between altitude and ambient temperature, pressure, and air density.

[0015] Preferably, the step of establishing an intercooler heat load model considering altitude changes, quantifying the impact of increased air compressor outlet temperature under altitude gradients on intercooler heat dissipation power consumption, and incorporating intercooler heat dissipation power consumption into the net power calculation of the fuel cell system includes the following steps:

[0016] Establish the intercooler heat load model, which is expressed as:

[0017] ;

[0018] in, For the intercooler heat load, Air mass flow rate, For the specific heat of air, The air temperature entering the intercooler, This refers to the air temperature at the intercooler outlet.

[0019] A power consumption model for the intercooler is established, including the power consumption of the circulating water pump and the power consumption of the cooling fan, which are expressed as follows:

[0020] ;

[0021] ;

[0022] in, For the power consumed by the water pump, This refers to the coolant flow rate. For the water pump head, It is the acceleration due to gravity. For pump efficiency, The specific heat capacity of the coolant. and These are the inlet and outlet temperatures of the coolant, respectively. The cooling fan consumes power. For cooling fan airflow, For fan efficiency, For fan air pressure, Due to environmental pressures, This refers to the specific heat capacity ratio of air. The function representing the solution for the pump head is a polynomial empirical function fitted using experimental data. Indicates ambient temperature;

[0023] Including the intercooler's heat dissipation power consumption in the calculation of the fuel cell system's net power, it is expressed as:

[0024] ;

[0025] in, For the net power of the fuel cell system, For the output power of the fuel cell stack, The air compressor consumes power. This is for the intercooler's heat dissipation power consumption;

[0026] The power consumption of an air compressor is expressed as:

[0027] ;

[0028] in, To supply pipeline pressure, This refers to the air compressor efficiency.

[0029] Preferably, the construction of the four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power aims to maximize the net power of the fuel cell system. A global optimization algorithm is used to solve for the optimal gas supply parameters under different altitudes and load currents. Specifically:

[0030] With the goal of maximizing the net power of the fuel cell system, a genetic algorithm is used to solve for the optimal gas supply parameters under different altitudes and load currents. The fitness function is expressed as:

[0031] ;

[0032] in, Represents the fitness function. Indicates the net power of the fuel cell system;

[0033] The constraints include:

[0034] ;

[0035] ;

[0036] ;

[0037] ;

[0038] in, This indicates the operating voltage of the air compressor. Indicates the superoxide ratio; Indicates the opening degree of the back pressure valve. Indicates the cathode pressure ratio; Indicates the load current. Indicates the lower limit of the load current. Indicates the upper limit of the load current; Altitude Indicates the lowest altitude. Indicates the highest altitude;

[0039] Based on the solution results, the optimal control rate expression is obtained through bivariate polynomial fitting:

[0040] ;

[0041] ;

[0042] in, The optimal operating voltage for the air compressor. For optimal back pressure valve opening; and It is an empirical constant. and Both represent empirical constant indices; This is the load current.

[0043] Preferably, the optimization space dimension of the genetic algorithm is 2, the population size is 100, and the maximum number of iterations is 25.

[0044] Preferably, the mutation probability and crossover probability of the genetic algorithm are set to 0.05 and 0.8, respectively.

[0045] Preferably, the oxygen ratio optimization range is 1.5~3.0, and the cathode pressure ratio optimization range is 1.5~2.5.

[0046] Preferably, the design employs a hierarchical perturbation observation method for optimizing the primary and secondary cycles of oxygen ratio and cathode pressure, and introduces an adaptive perturbation step size mechanism. This mechanism uses the optimal air supply parameters as feedforward values ​​to online correct the air compressor's operating voltage and back pressure valve opening. Specifically:

[0047] The main circulation optimizes the oxygen ratio by adjusting the air compressor's operating voltage, while the auxiliary circulation optimizes the cathode pressure by adjusting the back pressure valve opening. The main and auxiliary circulations are executed sequentially.

[0048] perturbation step size The adaptive dynamic adjustment based on the net power change rate of the fuel cell system is expressed as follows:

[0049] ;

[0050] ;

[0051] in, Based on the perturbation step size coefficient, As an adaptive factor, Due to power difference, The output power for the current cycle. This represents the output power of the previous cycle. To optimize the time cycle;

[0052] The execution logic of the hierarchical perturbation observation method is as follows:

[0053] ;

[0054] in, To preset the error threshold, , and These represent the operating voltage of the air compressor in the previous cycle, the operating voltage of the air compressor in the current cycle, and the operating voltage of the air compressor in the next cycle, respectively. , and These represent the back pressure valve opening in the previous cycle, the back pressure valve opening in the current cycle, and the back pressure valve opening in the next cycle, respectively. This indicates the perturbation step size of the air compressor's operating voltage. This indicates the disturbance step size of the back pressure valve opening; This means that if the conditions on the left are met, the calculation formula on the right will be executed.

[0055] Preferably, when a change in load current or altitude parameter is detected, the feedforward value is recalled and the hierarchical disturbance observation and optimization process is restarted until the maximum net system power point under the current operating condition is tracked. Specifically:

[0056] When a change in load current is detected or altitude change When the preset threshold is exceeded, the hierarchical perturbation observation method is triggered to reinitialize, using the offline-calibrated optimal gas supply parameters as the starting search point, thus avoiding the misjudgment and convergence delay problems of the traditional perturbation observation method when the operating conditions change abruptly.

[0057] The present invention also provides a fuel cell variable altitude power optimization system considering intercooler energy consumption, comprising:

[0058] The first module establishes a model, including a fuel cell stack model, a cathode air supply system model, and an atmospheric environmental parameter model.

[0059] The second module establishes a model to build a heat load model for the intercooler that takes into account altitude changes. It quantifies the impact of the increase in air compressor outlet air temperature under altitude gradient on the heat dissipation and power consumption of the intercooler and incorporates the heat dissipation and power consumption of the intercooler into the net power calculation of the fuel cell system.

[0060] The optimal parameter solution module constructs a four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power. With the goal of maximizing the net power of the fuel cell system, it uses a global optimization algorithm to solve for the optimal gas supply parameters under different altitudes and load currents.

[0061] The parameter correction module is designed with a hierarchical disturbance observation method that optimizes the main and auxiliary cycles of oxygen ratio and cathode pressure. It introduces an adaptive disturbance step size mechanism and uses the optimal air supply parameters as feedforward values ​​to correct the air compressor operating voltage and back pressure valve opening online.

[0062] The real-time monitoring module, when it detects changes in load current or altitude parameters, recalls the feedforward value and restarts the hierarchical disturbance observation and optimization process until it tracks the maximum net system power point under the current operating conditions.

[0063] The present invention has the following beneficial effects:

[0064] (1) This invention incorporates the heat dissipation power consumption of the intercooler under varying altitudes into the net power optimization target of the fuel cell system, overcoming the limitation of the prior art that only considers the power consumption of the air compressor, and making the calculation of the net power of the system more accurate;

[0065] (2) This invention designs a hierarchical perturbation observation method for the optimization of the main and auxiliary cycles for the two coupled variables of oxygen ratio and cathode pressure, which solves the problem that the traditional single-variable perturbation observation method cannot optimize multiple gas supply parameters at the same time. The optimal gas supply parameters under different altitudes and loads are solved offline by the global optimization algorithm as feedforward values, and then corrected online by the hierarchical perturbation observation method. When the load or altitude changes, the offline feedforward values ​​are automatically called to reinitialize the optimization process, which effectively avoids the misjudgment and convergence delay problems of the traditional perturbation observation method when the operating conditions change suddenly, thus ensuring both optimization accuracy and real-time requirements.

[0066] (3) The present invention dynamically adjusts the disturbance step size according to the net power change rate of the system, which improves the convergence speed while ensuring convergence accuracy.

[0067] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the present invention is not limited to the embodiments. Attached Figure Description

[0068] Figure 1 This is a flowchart illustrating the steps of a method for optimizing the power of a fuel cell at varying altitudes, taking into account the energy consumption of the intercooler, according to an embodiment of the present invention.

[0069] Figure 2 This is a flowchart illustrating a method for optimizing the power of a fuel cell at varying altitudes, taking into account the energy consumption of the intercooler, according to an embodiment of the present invention.

[0070] Figure 3 This invention illustrates the variations in intercooler heat load and heat dissipation power consumption at different altitudes according to embodiments of the invention.

[0071] Figure 4 This describes the convergence process of the optimal gas supply parameters obtained by the genetic algorithm in an embodiment of the present invention.

[0072] Figure 5 The results of solving the optimal control law under different altitudes and load currents in the embodiments of the present invention;

[0073] Figure 6 This is a real-time power optimization result under customized variable altitude conditions in an embodiment of the present invention;

[0074] Figure 7 This is a schematic diagram of a fuel cell variable altitude power optimization system that takes into account the energy consumption of the intercooler, according to an embodiment of the present invention. Detailed Implementation

[0075] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0076] See Figure 1 and Figure 2 As shown in the figure, an embodiment of the present invention provides a method for optimizing the power of a fuel cell at varying altitudes, taking into account the energy consumption of the intercooler, comprising the following steps:

[0077] S101, Establish fuel cell stack model, cathode air supply system model and atmospheric environment parameter model;

[0078] S102, Establish a heat load model for the intercooler that takes into account altitude changes, quantify the impact of the increase in air compressor outlet air temperature under altitude gradient on the heat dissipation power consumption of the intercooler, and incorporate the heat dissipation power consumption of the intercooler into the net power calculation of the fuel cell system.

[0079] S103, construct a four-dimensional mapping relationship between load current, gas supply parameters, stack performance and parasitic power. With the goal of maximizing the net power of the fuel cell system, use a global optimization algorithm to solve for the optimal gas supply parameters under different altitudes and load currents, including the air compressor operating voltage and back pressure valve opening.

[0080] S104 is designed with a hierarchical perturbation observation method that optimizes the main and auxiliary cycles of oxygen ratio and cathode pressure. It introduces an adaptive perturbation step size mechanism and uses the best gas supply parameters as feedforward values ​​to correct the air compressor operating voltage and back pressure valve opening online.

[0081] S105: When a change in load current or altitude parameter is detected, the feedforward value is recalled and the hierarchical disturbance observation and optimization process is restarted until the maximum net system power point under the current operating condition is tracked.

[0082] Specifically, in S101, a fuel cell stack model is established based on electrochemical principles, including open-circuit voltage, activation polarization voltage, ohmic polarization voltage, and concentration polarization voltage. The voltage of a single fuel cell unit can be expressed as:

[0083] (1)

[0084] In the formula, E nerst V is the open-circuit voltage of the fuel cell. act V is the electrode activation polarization voltage. ohm V is the ohmic polarization voltage. con This is the concentration polarization voltage.

[0085] A fifth-order nonlinear cathode air supply system model is established based on the law of conservation of mass and the ideal gas law, including an air compressor model, a cathode supply manifold model, a cathode flow channel model, and an exhaust manifold model.

[0086] An atmospheric environmental parameter model was established based on the international standard atmospheric model. The relationship between ambient temperature, pressure, and air density and altitude is as follows:

[0087] (2)

[0088] (3)

[0089] (4)

[0090] Where T0 is the sea level temperature. The temperature is at an altitude h, and the unit of temperature is K. Sea level pressure, The pressure is at an altitude h, and the unit of pressure is P; h is the altitude, and the unit of altitude is m. M is the air density at an altitude h. Air For the molar mass of air, Indicates the compression factor. Represents the universal gas constant. This indicates the molar mass of water vapor.

[0091] Among them, the influence parameters of the atmospheric environment parameter model are used as inputs into the cathode air supply system model; all the above models are based on bench test data to verify the accuracy of the models and ensure that the model output error is controlled within 5%.

[0092] See Figure 3 As shown, in S102, the heat load of the intercooler comes from the heat generated by the air compressor compressing air:

[0093] (5)

[0094] In the formula, W air，cp For air mass flow rate, c air For the specific heat of air, T air,in T represents the air temperature entering the intercooler. air,out This refers to the air temperature at the intercooler outlet.

[0095] The outlet air temperature of the air compressor increases with altitude, and its heat load increases accordingly. Under rated operating conditions, the intercooler heat load increases from 10.41kW in a plain environment to 18.22kW at an altitude of 4000m.

[0096] The power consumption of the circulating water pump is:

[0097] (6)

[0098] In the formula, W cool H represents the coolant flow rate. pump Let g be the pump head, g be the acceleration due to gravity, and η be the acceleration due to gravity. pump For water pump efficiency.

[0099] The power consumption of the cooling fan is:

[0100] (7)

[0101] In the formula, W air,fan η is the airflow rate of the cooling fan. fan For fan efficiency, p fan For fan air pressure, p atm Due to environmental pressure, γc This is the specific heat ratio of air.

[0102] The total heat dissipation power of the intercooler is:

[0103] (8)

[0104] The net power of the fuel cell system is:

[0105] (9)

[0106] Among them, P st P is the output power of the fuel cell stack. comp For the power consumed by the air compressor, P inter This refers to the power consumption for heat dissipation of the intercooler.

[0107] The power consumption of the air compressor is calculated as follows:

[0108] (10)

[0109] Where, p sm To supply pipeline pressure, η comp This refers to the air compressor efficiency.

[0110] See Figure 4 As shown, in step S103, a four-dimensional mapping relationship is constructed between load current, gas supply parameters, fuel cell stack performance, and parasitic power. With the goal of maximizing the net power of the fuel cell system, a genetic algorithm is used to solve for the optimal gas supply parameters under different altitudes and load currents. Here, gas supply parameters refer to the parameters in the cathode air supply system model; fuel cell stack performance refers to the performance of the fuel cell stack model; and parasitic power is the power consumed by the auxiliary system, specifically the power consumed by the air compressor and the heat dissipation power of the intercooler in this embodiment.

[0111] The fitness function and optimization variable are the superoxide ratio λ. O2 And cathode pressure ratio PR ca The constraints are:

[0112] (11)

[0113] The solution results are as follows Figure 5 As shown. Based on the solution results, the optimal control rate expression is obtained through bivariate polynomial fitting:

[0114] (12)

[0115] Among them, a ij b ij I is an empirical constant. st denoted as load current and h as altitude.

[0116] Specifically, in S104, the hierarchical disturbance observation method adopts a main-auxiliary cycle optimization architecture: the main cycle optimizes the oxygen ratio (achieved by adjusting the working voltage of the air compressor), and the auxiliary cycle optimizes the cathode pressure (achieved by adjusting the opening of the back pressure valve), and the two cycles are executed sequentially.

[0117] The net power difference between the current period and the previous period is:

[0118] (13)

[0119] Where Δt is the optimization time period.

[0120] The disturbance step size is adaptively adjusted according to the net power change rate:

[0121] (14)

[0122] Where k1 is the basic perturbation step size coefficient and k2 is the adaptive factor.

[0123] The optimized execution logic is as follows:

[0124] (15)

[0125] Where, d net The preset error threshold is denoted by u, which represents the air compressor operating voltage or the back pressure valve opening.

[0126] The hierarchical perturbation observation method uses the offline calibration value obtained from S103 as the feedforward starting point, which effectively shortens the optimization time.

[0127] Specifically, in S105, the feedforward value is re-called to restart the optimization when the operating conditions change. When a change in load current |ΔI is detected... st When the change in altitude, Δh, exceeds the preset threshold, the current loop is exited, the offline calibration feedforward value of step S3 is called again, the hierarchical perturbation observation method is initialized, and the optimization process is restarted.

[0128] In this embodiment, the selected fuel cell system has a rated power of 100kW, a rated current of 400A, and 450 individual cells. The genetic algorithm has an optimization space dimension of 2, a population size of 100, and a maximum number of iterations of 25. The mutation and crossover probabilities of the genetic algorithm are set to 0.05 and 0.8, respectively. The optimization range for the excess oxygen ratio is 1.5~3.0, and the optimization range for the cathode pressure ratio is 1.5~2.5. The optimization time period Δt is 1.0s, and the error threshold d... net It is 10W.

[0129] To verify the superior performance of the proposed strategy, the optimization effect of fuel cell system power was compared and analyzed under custom altitude and load conditions (e.g., Figure 6As shown), and compared with the traditional non-optimization strategy (peroxygen ratio λ) O2 =2 and cathode pressure ratio PR ca =2, denoted as Strategy I), traditional single-layer P&O method (only optimizing the superoxide ratio λ). O2 Cathode pressure ratio PR ca The proposed power hierarchical optimization method is compared with five other strategies: a fixed value (strategy II), a global optimization algorithm (strategy III), a hierarchical optimization method without feedforward (strategy IV), and a partitioning optimization method with feedforward but reversed main and auxiliary loop optimization order (strategy V). Compared with the other five strategies, the proposed power hierarchical optimization method can improve power efficiency by up to 1.53%, 2.14%, 2.03%, 2.58%, and 3.29%, respectively, demonstrating good power optimization performance.

[0130] See Figure 7 The diagram shown is a structural schematic of a fuel cell variable altitude power optimization system considering intercooler energy consumption according to an embodiment of the present invention, comprising:

[0131] The first model building module 701 establishes a fuel cell stack model, a cathode air supply system model, and an atmospheric environment parameter model.

[0132] The second model building module 702 establishes a heat load model for the intercooler that takes into account altitude changes, quantifies the impact of the increase in air compressor outlet air temperature under altitude gradient on the heat dissipation and power consumption of the intercooler, and incorporates the heat dissipation and power consumption of the intercooler into the net power calculation of the fuel cell system.

[0133] The optimal parameter solution module 703 constructs a four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power. With the goal of maximizing the net power of the fuel cell system, it uses a global optimization algorithm to solve for the optimal gas supply parameters under different altitudes and load currents, including the air compressor operating voltage and back pressure valve opening.

[0134] The parameter correction module 704 is designed with a hierarchical disturbance observation method that optimizes the main and auxiliary cycles of oxygen ratio and cathode pressure. It introduces an adaptive disturbance step size mechanism and uses the best gas supply parameters as feedforward values ​​to correct the air compressor operating voltage and back pressure valve opening online.

[0135] The real-time monitoring module 705, when detecting changes in load current or altitude parameters, recalls the feedforward value and restarts the hierarchical disturbance observation and optimization process until it tracks the maximum net system power point under the current operating conditions.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for optimizing the power of a fuel cell at varying altitudes, considering the energy consumption of the intercooler, characterized in that, Includes the following steps: Establish fuel cell stack models, cathode air supply system models, and atmospheric environmental parameter models; Establish a heat load model for the intercooler that takes into account altitude changes, quantify the impact of the increase in air compressor outlet air temperature under altitude gradient on the heat dissipation power consumption of the intercooler, and incorporate the heat dissipation power consumption of the intercooler into the net power calculation of the fuel cell system. A four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power is constructed. With the goal of maximizing the net power of the fuel cell system, a global optimization algorithm is used to solve for the optimal gas supply parameters under different altitudes and load currents, including the air compressor operating voltage and back pressure valve opening. The design incorporates a hierarchical perturbation observation method that optimizes the main and auxiliary cycles for oxygen ratio and cathode pressure. An adaptive perturbation step size mechanism is introduced to use the optimal air supply parameters as feedforward values ​​to correct the air compressor operating voltage and back pressure valve opening online. When a change in load current or altitude parameter is detected, the feedforward value is recalled and the hierarchical disturbance observation optimization process is restarted until the maximum net system power point under the current operating condition is tracked.

2. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 1, characterized in that, The establishment of the fuel cell stack model and the cathode air supply system model includes: An electric stack model was established based on electrochemical principles, including open-circuit voltage, activation polarization voltage, ohmic polarization voltage, and concentration polarization voltage. Establish a model of the cathode air supply system, including an air compressor model, a cathode supply manifold model, a cathode flow channel model, and an exhaust manifold model; An atmospheric environmental parameter model was established based on the international standard atmospheric model to reflect the relationship between altitude and ambient temperature, pressure, and air density.

3. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 1, characterized in that, The establishment of an intercooler heat load model considering altitude changes, quantifying the impact of increased air compressor outlet temperature on intercooler heat dissipation power consumption under altitude gradients, and incorporating intercooler heat dissipation power consumption into the net power calculation of the fuel cell system includes the following steps: Establish the intercooler heat load model, which is expressed as: ； in, For the intercooler heat load, Air mass flow rate, For the specific heat of air, The air temperature entering the intercooler, This refers to the air temperature at the intercooler outlet. A power consumption model for the intercooler is established, including the power consumption of the circulating water pump and the power consumption of the cooling fan, which are expressed as follows: ； ； in, For the power consumed by the water pump, This refers to the coolant flow rate. For the water pump head, It is the acceleration due to gravity. For pump efficiency, The specific heat capacity of the coolant. and These are the inlet and outlet temperatures of the coolant, respectively. The cooling fan consumes power. For cooling fan airflow, For fan efficiency, For fan air pressure, Due to environmental pressures, This refers to the specific heat capacity ratio of air. The function representing the solution for the pump head is a polynomial empirical function fitted using experimental data. Indicates ambient temperature; Including the intercooler's heat dissipation power consumption in the calculation of the fuel cell system's net power, it is expressed as: ； in, For the net power of the fuel cell system, For the output power of the fuel cell stack, The air compressor consumes power. This is for the intercooler's heat dissipation power consumption; The power consumption of an air compressor is expressed as: ； in, To supply pipeline pressure, This refers to the air compressor efficiency.

4. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 1, characterized in that, The construction of a four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power aims to maximize the net power of the fuel cell system. A global optimization algorithm is used to solve for the optimal gas supply parameters at different altitudes and load currents. Specifically: With the goal of maximizing the net power of the fuel cell system, a genetic algorithm is used to solve for the optimal gas supply parameters under different altitudes and load currents. The fitness function is expressed as: ； in, Represents the fitness function. Indicates the net power of the fuel cell system; The constraints include: ； ； ； ； in, This indicates the operating voltage of the air compressor. Indicates the superoxide ratio; Indicates the opening degree of the back pressure valve. Indicates the cathode pressure ratio; Indicates the load current. Indicates the lower limit of the load current. Indicates the upper limit of the load current; Altitude Indicates the lowest altitude. Indicates the highest altitude; Based on the solution results, the optimal control rate expression is obtained through bivariate polynomial fitting: ； ； in, The optimal operating voltage for the air compressor. To achieve the optimal back pressure valve opening; and It is an empirical constant. and Both represent empirical constant indices; This is the load current.

5. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 4, characterized in that, The optimization space dimension of the genetic algorithm is 2, the population size is 100, and the maximum number of iterations is 25.

6. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 4, characterized in that, The mutation probability and crossover probability of the genetic algorithm are set to 0.05 and 0.8, respectively.

7. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 1, characterized in that, The optimized range for the oxygen permeability ratio is 1.5 to 3.0, and the optimized range for the cathode pressure ratio is 1.5 to 2.

5.

8. The fuel cell variable altitude power optimization method considering intercooler energy consumption according to claim 1, characterized in that, The design employs a hierarchical perturbation observation method for optimizing the primary and secondary cycles of oxygen ratio and cathode pressure. It introduces an adaptive perturbation step size mechanism, using the optimal air supply parameters as feedforward values ​​to online correct the air compressor's operating voltage and back pressure valve opening. Specifically: The main circulation optimizes the oxygen ratio by adjusting the air compressor's operating voltage, while the auxiliary circulation optimizes the cathode pressure by adjusting the back pressure valve opening. The main and auxiliary circulations are executed sequentially. perturbation step size The adaptive dynamic adjustment based on the net power change rate of the fuel cell system is expressed as follows: ； ； in, Based on the perturbation step size coefficient, As an adaptive factor, Due to power difference, The output power for the current cycle. This represents the output power of the previous cycle. To optimize the time cycle; The execution logic of the hierarchical perturbation observation method is as follows: ； in, To preset the error threshold, , and These represent the operating voltage of the air compressor in the previous cycle, the operating voltage of the air compressor in the current cycle, and the operating voltage of the air compressor in the next cycle, respectively. , and These represent the back pressure valve opening in the previous cycle, the back pressure valve opening in the current cycle, and the back pressure valve opening in the next cycle, respectively. This indicates the perturbation step size of the air compressor's operating voltage. This indicates the disturbance step size of the back pressure valve opening. This means that if the conditions on the left are met, the calculation formula on the right will be executed.

9. The method for optimizing the power of a fuel cell at varying altitudes, considering intercooler energy consumption, as described in claim 1, is characterized in that... When a change in load current or altitude parameter is detected, the feedforward value is recalled and the hierarchical disturbance observation and optimization process is restarted until the maximum net system power point under the current operating condition is tracked. Specifically: When a change in load current is detected or altitude change When the preset threshold is exceeded, the hierarchical perturbation observation method is triggered to reinitialize, using the offline-calibrated optimal gas supply parameters as the starting search point, thus avoiding the misjudgment and convergence delay problems of the traditional perturbation observation method when the operating conditions change abruptly.

10. A fuel cell variable altitude power optimization system considering intercooler energy consumption, characterized in that, include: The first module establishes a model, including a fuel cell stack model, a cathode air supply system model, and an atmospheric environmental parameter model. The second module establishes a model to build a heat load model for the intercooler that takes into account altitude changes. It quantifies the impact of the increase in air compressor outlet air temperature under altitude gradient on the heat dissipation and power consumption of the intercooler and incorporates the heat dissipation and power consumption of the intercooler into the net power calculation of the fuel cell system. The optimal parameter solution module constructs a four-dimensional mapping relationship between load current, gas supply parameters, stack performance, and parasitic power. With the goal of maximizing the net power of the fuel cell system, it uses a global optimization algorithm to solve for the optimal gas supply parameters under different altitudes and load currents. The parameter correction module is designed with a hierarchical disturbance observation method that optimizes the main and auxiliary cycles of oxygen ratio and cathode pressure. It introduces an adaptive disturbance step size mechanism and uses the optimal air supply parameters as feedforward values ​​to correct the air compressor operating voltage and back pressure valve opening online. The real-time monitoring module, when it detects changes in load current or altitude parameters, recalls the feedforward value and restarts the hierarchical disturbance observation and optimization process until it tracks the maximum net system power point under the current operating conditions.

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