A hydrogen supply limited health constraint collaborative control method for a pemfc-haice hybrid system

Abstract

The present application belongs to the technical field of control of hybrid power system, and particularly relates to a hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system, which acquires the health state of the PEMFC unit by collecting the state information of the hybrid system, determines the current power upper limit and the power gap thereof; acquires the current hydrogen supply capacity to correct the hydrogen supply constraint for the power gap to obtain a compensable gap; inputs the compensable gap into a preset target equivalence ratio mapping relationship to obtain the target equivalence ratio of the HAICE unit, and further obtains the actual compensation power of the HAICE unit to determine the total output power of the system after collaborative control. The present application unifies the PEMFC health state sensing, system hydrogen supply boundary constraint and HAICE combustion parameter dynamic adjustment, solves the problem that the prior art is difficult to simultaneously consider the PEMFC life protection, hydrogen resource reasonable distribution, HAICE stable combustion and emission control under the conditions of PEMFC aging, hydrogen supply limitation or fluctuation, and effectively improves the overall output capacity and operation robustness of the hybrid system.

Description

Technical Field

[0001] This invention belongs to the field of control technology for hybrid power systems, specifically relating to a collaborative control method for hydrogen supply-constrained health conditions in PEMFC-HAICE hybrid systems. Background Technology

[0002] With the increasing global demand for zero-carbon power, hybrid power systems consisting of proton exchange membrane fuel cells (PEMFCs) and hydrogen-ammonia internal combustion engines (HAICEs) are showing great potential in heavy-duty transportation (such as heavy trucks, ships, and construction machinery) and distributed energy. This system aims to combine the high efficiency and low emissions of PEMFCs with the high power density, strong transient response, and convenient fuel (ammonia) storage and transportation advantages of HAICEs. In this system, the PEMFC typically serves as the base load power unit, bearing the basic load of the system, while the HAICE acts as a dynamic power compensation unit, providing power compensation during transient high-power demand conditions such as acceleration and hill climbing.

[0003] However, existing technical solutions mainly focus on system integration and waste heat utilization, emphasizing fuel injection and combustion control on the engine side. They have poor coordination and under long-term complex operating conditions, the PEMFC will experience a decline in its state of health (SOH) due to aging mechanisms such as membrane dehydration and catalyst decay. Under transient operating conditions, there may be insufficient or fluctuating hydrogen supply, and the combustion stability of HAICE cannot be guaranteed, thus affecting the service life of the hybrid power system. Summary of the Invention

[0004] To address the problems existing in the prior art, the purpose of this invention is to provide a collaborative control method for hydrogen supply-constrained health conditions in PEMFC-HAICE hybrid systems, which improves the overall output capacity, dynamic adaptability, and operational robustness of the hybrid system under complex operating conditions.

[0005] The technical solution of this invention is: A collaborative control method for hydrogen supply-constrained health constraints in PEMFC-HAICE hybrid systems includes the following steps: The status information of the hybrid system is collected. The hybrid system includes an ammonia storage and supply unit, an ammonia cracking hydrogen supply unit, a hydrogen buffer unit, a PEMFC unit, a HAICE unit, and a hybrid system controller. The current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit is obtained. The current health status of the PEMFC unit is obtained based on the status information, and the current power limit of the PEMFC unit is determined based on the health status. Based on the current power limit of the PEMFC unit and the preset reference output power of the PEMFC unit in a healthy state, the power gap of the PEMFC unit is determined. Based on the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit, the power gap of the PEMFC unit is corrected by hydrogen supply constraint to obtain the compensable gap after hydrogen supply constraint. The compensable gap after the hydrogen supply constraint is input into the preset target equivalent ratio mapping relationship to obtain the target equivalent ratio of the HAICE unit; Based on the target equivalent ratio of the HAICE unit, the actual compensation power of the HAICE unit is obtained through the HAICE output mapping relationship; Based on the actual compensation power of the HAICE unit and the current power limit of the PEMFC unit, the total output power of the system after coordinated control is determined.

[0006] Preferably, the status information of the hybrid system includes: the stack voltage, stack current, output power, temperature and internal resistance characteristic parameters of the PEMFC unit; the outlet hydrogen flow rate, cracking temperature and hydrogen production capacity of the ammonia cracking hydrogen supply unit; the hydrogen storage capacity, pressure and releasable hydrogen flow rate of the hydrogen buffer unit; and the engine speed, load, output power and related operating status parameters of the HAICE unit.

[0007] Preferably, the current health status of the PEMFC unit is obtained by: determining it by monitoring one or more of the characteristics of the PEMFC unit, such as stack voltage decay, internal resistance growth, and output power decay, or by obtaining it based on historical operating data through a health status assessment model.

[0008] Preferably, the power gap is corrected by hydrogen supply constraints to obtain a compensable gap after the hydrogen supply constraints, including: Based on the status information, it is determined whether the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit meets the requirement of compensating the power gap; if it does, the power gap is taken as the compensable gap after the hydrogen supply constraint; if it does not, the maximum compensation power that the HAICE unit can support at the current moment is determined according to the current hydrogen supply capacity, and the power gap is compared with the maximum compensation power to obtain the smaller value as the compensable gap after the hydrogen supply constraint.

[0009] Preferably, the preset target equivalence ratio mapping relationship is implemented by one-dimensional lookup table, two-dimensional lookup table, rule base or function mapping method, and the determination principle of the target equivalence ratio mapping relationship includes: under the premise of meeting the current power compensation requirements, the operating point of the HAICE unit is in the stable combustion region, and nitrogen oxide emissions and ammonia escape emissions are constrained.

[0010] Preferably, the preset target equivalence ratio mapping relationship also takes one or more of the engine speed, load, hydrogen blending ratio and air coefficient of the HAICE unit as additional input parameters, and combines them with the compensable gap after the hydrogen supply constraint to obtain the target equivalence ratio of the HAICE unit.

[0011] Preferably, the input parameters for the HAICE output mapping relationship include the compensable gap after hydrogen supply constraints, the target equivalence ratio, and engine operating parameters.

[0012] Preferably, the current power limit of the PEMFC unit is determined according to the following formula: , In the formula, This represents the current power limit of the PEMFC unit. This is the reference output power of the PEMFC unit in a healthy state. This indicates the health status of the PEMFC unit.

[0013] Preferably, the power gap is determined according to the following formula: , In the formula, For power gap, This represents the current power limit of the PEMFC unit. This is the reference output power of the PEMFC unit in a healthy state.

[0014] Preferably, the determination of whether the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit meets the requirements for compensating the power gap is based on the following formula: , In the formula, Real-time hydrogen supply flow rate for the ammonia cracking hydrogen supply unit. The hydrogen buffer unit can release hydrogen flow. The target hydrogen flow rate required to compensate the current power deficit of the HAICE unit, the It can be obtained by conversion based on the current power deficit, the lower heating value of hydrogen, and the equivalent power compensation efficiency of the HAICE unit, or determined by the calibrated power deficit-hydrogen flow rate mapping relationship.

[0015] Compared with the prior art, the present invention provides a collaborative control method for hydrogen supply-constrained health requirements in PEMFC-HAICE hybrid systems, which has the following advantages: This invention first determines the current power limit of a PEMFC unit by real-time acquisition of system status and evaluation of its state of health (SOH). This allows for dynamic limitation of the PEMFC's output based on its actual aging, avoiding forced overload operation under power shortages and thus proactively protecting the PEMFC's lifespan. Secondly, by introducing the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit, the power shortage is constrained and corrected to obtain a "compensable shortage." This ensures that the power compensation demand of the HAICE unit never exceeds the system's real-time hydrogen supply capacity limit, achieving rational allocation and utilization of hydrogen fuel resources and preventing power compensation failure or system instability due to insufficient hydrogen supply. Furthermore, by mapping the "compensable shortage" to the target equivalence ratio of the HAICE unit, its actual compensation power is obtained. This allows the HAICE's combustion parameters (equivalence ratio) to be dynamically and precisely adjusted according to the actual power compensation demand after hydrogen supply constraint correction, rather than using fixed parameters. This ensures that the HAICE unit operates in a stable combustion region under various operating conditions and is beneficial for the synergistic control of nitrogen oxides (NOx). x The system's total output power is determined by reducing emissions such as ammonia slip (NH3Slip) and other emissions. This allows for the determination of the optimal or feasible output under multiple constraints (health constraints, hydrogen supply constraints, and combustion constraints), significantly improving the overall output capacity, dynamic adaptability, and operational robustness of the hybrid system under complex operating conditions. Attached Figure Description

[0016] Figure 1 This is a block diagram of the hybrid system structure in an embodiment of the present invention; Figure 2 This is a flowchart of the collaborative control method in an embodiment of the present invention; Figure 3 This is a block diagram illustrating the collaborative control principle in an embodiment of the present invention; Figure 4 This is a comparison chart of system output power in an embodiment of the present invention; Figure 5 This is a time-series variation diagram of key power variables in an embodiment of the present invention; Figure 6 This is a time-series variation diagram of the target equivalence ratio in an embodiment of the present invention. Detailed Implementation

[0017] 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 and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0019] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0020] With the continued growth in global demand for zero-carbon power, hybrid systems consisting of proton exchange membrane fuel cells (PEMFCs) and hydrogen-ammonia internal combustion engines (HAICEs) are becoming an important technological route in heavy-duty transportation and distributed energy fields. PEMFCs offer advantages such as high electrical efficiency, low noise, and suitability as high-efficiency baseload power units, typically handling the system's base load output. HAICEs, on the other hand, utilize the convenience of ammonia fuel storage and transportation, its high energy density, and the increased combustion rate and faster transient response after hydrogen blending, undertaking dynamic power compensation tasks under high-load conditions such as acceleration and hill climbing. However, under conditions of long-term, significant load variations, fluctuating hydrogen supply, unbalanced hot water management, and frequent start-stop cycles, PEMFCs are prone to degradation phenomena such as catalyst decay, membrane dehydration, membrane electrode aging, and flow field plate corrosion, leading to polarization curve shifts, increased internal resistance, and decreased maximum output capacity. Meanwhile, although HAICEs possess strong transient power compensation capabilities, their combustion process is highly sensitive to stoichiometry, hydrogen blending ratio, ignition, and gas supply conditions, exhibiting a limited stable combustion range and NO2 content. x There are issues such as difficulty in co-optimizing with NH3Slip and the susceptibility to misfires under lean-burn conditions. Furthermore, the hydrogen in the mixed system typically comes from the ammonia cracker and buffer hydrogen storage unit, and its hydrogen production process is itself affected by reaction temperature, thermal management status, dynamic hysteresis, and capacity limits. Therefore, in a system where PEMFC, HAICE, and cracked hydrogen supply units coexist, the control problem is no longer a simple "power allocation" problem, but a cross-domain coupled control problem involving hydrogen supply resource constraints, component health constraints, combustion / emission constraints, and dynamic power compensation requirements.

[0021] To enhance the overall output capacity, dynamic adaptability, and operational robustness of hybrid systems under complex operating conditions, this embodiment provides a coordinated control method for hydrogen supply-constrained health conditions in PEMFC-HAICE hybrid systems. By integrating PEMFC health status, output decay characteristics, cracking hydrogen supply capacity, and HAICE combustion boundaries and emission constraints, and dynamically coordinating the power distribution, hydrogen flow distribution, and engine target equivalence ratio between PEMFC and HAICE, this method achieves the goal of balancing PEMFC lifespan protection, system hydrogen supply coordination, stable HAICE combustion, and NOx and NH3 emission control under conditions of PEMFC aging and hydrogen supply constraints.

[0022] See Figure 1 As shown, the hybrid system mainly includes an ammonia storage and supply unit, an ammonia cracking hydrogen supply unit, a hydrogen buffer unit, a PEMFC unit, a HAICE unit, a power conversion unit, a load, and a hybrid system controller. Based on the existing hybrid system hardware, the hybrid system controller coordinates the PEMFC unit, HAICE unit, ammonia cracking hydrogen supply unit, and hydrogen buffer unit in a unified manner, enabling the system to maintain PEMFC lifespan protection, stable HAICE power replenishment, and overall system output capacity even under conditions of PEMFC aging, limited or fluctuating hydrogen supply.

[0023] like Figure 1 As shown, the ammonia storage and supply unit stores and transports ammonia, providing fuel for the ammonia cracking hydrogen supply unit and the HAICE unit; the ammonia cracking hydrogen supply unit cracks ammonia into hydrogen-rich gas under external heating or waste heat conditions and transports the resulting hydrogen to the hydrogen buffer unit; the hydrogen buffer unit smooths out fluctuations in cracked hydrogen supply, compensates for hydrogen supply lag, and provides hydrogen support to the PEMFC unit and HAICE unit respectively; the PEMFC unit is responsible for the system's basic power output, characterized by high efficiency, but its allowable output power decreases as the state of oxygen (SOH) decreases; the HAICE unit is responsible for dynamic power compensation, and its output capacity is closely related to hydrogen supply conditions and combustion parameters; the power conversion unit matches the output power of the PEMFC unit and HAICE unit and supplies power to the load; the hybrid system controller outputs coordinated control commands to the PEMFC unit, HAICE unit, and hydrogen supply link according to the system status, hydrogen supply status, and power demand (dashed arrows indicate the control command and status signal transmission relationship between the hybrid system controller and each unit). This structure not only shows the positional and connection relationships of each functional unit in the system, but also clarifies the distribution paths of material flow, power flow and control signal flow, providing a platform for the implementation of subsequent control methods.

[0024] Based on the aforementioned hardware system, this invention provides a control route: when the permissible output power of the PEMFC unit decreases due to membrane dehydration, catalyst degradation, or other health risks, the system does not directly transfer the power shortfall to the HAICE unit using a fixed ratio or fixed equivalence ratio strategy. Instead, it first comprehensively assesses the current hydrogen supply capacity and then generates the target combustion parameters and actual compensation output of the HAICE unit within the feasible hydrogen supply domain. This avoids power compensation failure, combustion degradation, or even emission degradation caused by insufficient hydrogen supply or combustion parameter mismatch. The execution sequence of this process is as follows: Figure 2 As shown: First, the hybrid system status information is collected to estimate the state of health (SOH) of the PEMFC and determine its current power limit. Then, the power gap is determined based on the difference between the baseline output power and the current allowable power. Next, it is determined whether the current hydrogen supply meets the compensation requirements. If the hydrogen supply is insufficient, the power gap is corrected by hydrogen supply constraints. Based on this, the target equivalence ratio of HAICE and the corresponding output are further generated, and finally the total system output after coordinated control is formed, which is compared with the fixed strategy or the next control cycle is entered. This invention is not a simple power allocation method, but a multi-stage control process that includes health status identification, hydrogen supply constraint judgment, combustion parameter mapping, and output coordination.

[0025] Based on the above control approach, this invention provides a collaborative control method for hydrogen supply-constrained health requirements in PEMFC-HAICE hybrid systems, such as... Figure 2 As shown, it includes the following steps: Step 1: Collect the status information of the hybrid system.

[0026] Step 2: Obtain the current health status of the PEMFC unit based on the status information, and determine the current power limit of the PEMFC unit based on the health status.

[0027] Step 3: Based on the current power limit of the PEMFC unit and the preset reference output power of the PEMFC unit in a healthy state, determine the power gap of the PEMFC unit.

[0028] Step 4: Obtain the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit, and perform hydrogen supply constraint correction on the power gap of the PEMFC unit based on the current hydrogen supply capacity to obtain the compensable gap after hydrogen supply constraint. Specifically, the hydrogen supply constraint correction for the power gap involves: determining whether the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit meets the requirements for compensating the power gap based on the state information; if it does, the power gap is taken as the compensable gap after hydrogen supply constraint; if it does not, the maximum compensable power that the HAICE unit can support at the current moment is determined based on the current hydrogen supply capacity, and the power gap is compared with the maximum compensable power, with the smaller value being taken as the compensable gap after hydrogen supply constraint.

[0029] Step 5: Input the compensable gap after hydrogen supply constraint into the preset target equivalence ratio mapping relationship to obtain the target equivalence ratio of the HAICE unit.

[0030] Step 6: Based on the target equivalent ratio of the HAICE unit, obtain the actual compensation power of the HAICE unit through the HAICE output mapping relationship.

[0031] Step 7: Determine the total output power of the system after coordinated control based on the actual compensation power of the HAICE unit and the current power limit of the PEMFC unit.

[0032] Specifically, during the execution of this invention, the hybrid system status information includes: the stack voltage, stack current, output power, temperature, and internal resistance characteristic parameters of the PEMFC unit; the outlet hydrogen flow rate, cracking temperature, and hydrogen production capacity of the ammonia cracking hydrogen supply unit; the hydrogen storage capacity, pressure, and releasable hydrogen flow rate of the hydrogen buffer unit; and the engine speed, load, output power, and related operating status parameters of the HAICE unit. This status information can be obtained through voltage sensors, current sensors, temperature sensors, pressure sensors, flow sensors, and the controller's internal estimation module, and then input into the hybrid system controller for unified processing. For this invention, the PEMFC aging process can be characterized through aging perturbations in simulation; in other execution schemes, the current SOH of the PEMFC can also be obtained through voltage decay, internal resistance growth, output power decay, or a health assessment model based on historical operating data.

[0033] like Figure 3 The diagram of the cooperative control principle shown first simulates the decline in the health status of a PEMFC cell using a PEMFC aging disturbance module. Then, the PEMFC allowable power limit module maps the State of Health (SOH) to the power that the PEMFC can currently safely output. Based on this, the PEMFC reference output power is compared with the current allowable power to obtain the power gap Δ. P This amount represents the power demand requiring external compensation due to PEMFC aging; subsequently, the power gap enters the gap module after the hydrogen supply constraint, where the hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit is combined to address the power gap Δ. P The correction is performed to obtain the actual compensation gap that the HAICE unit can handle under the current hydrogen supply conditions. The corrected gap is input into the target equivalent ratio mapping module to generate the target equivalent ratio of the HAICE unit. Then, the target equivalent ratio is converted into the actual compensation power that the HAICE can provide through the HAICE output lookup module. Finally, the actual output of HAICE is superimposed with the current output of PEMFC to form the system output after coordinated control, and is compared with the system output under the traditional fixed strategy.

[0034] In the collaborative control process of this invention, the PEMFC unit's SOH Its output capability attenuation can be estimated and characterized based on the degree of attenuation. The reference output power of the PEMFC unit in a healthy state is denoted as... The current power limit of the PEMFC unit is denoted as In the current simulation experiment, SOH is used for Characterizes the degree of degradation of PEMFC output capability relative to the healthy state baseline output capability.

[0035] Accordingly, the current power limit of PEMFC can be expressed as: , In other implementation schemes, the stack voltage, unit consistency, internal resistance estimate, temperature rise characteristics, or data-driven models can also be used. SOH As long as the current health status of PEMFC can be characterized and its allowable output capacity can be adjusted accordingly, the implementation of this invention will not be affected.

[0036] And the power gap Δ P This can be obtained from the difference between the PEMFC reference output power and the current power limit, i.e.: The power gap Δ P This reflects the power demand that needs to be compensated by other power units due to the decline in the health status of the PEMFC. Assuming that in the current simulation verification... When PEMFCs age and cause When the power drops to 40kW, the power gap Δ P It is 10kW.

[0037] like Figure 3 As shown in the overall cooperative control principle diagram: (1) PEMFC aging disturbance reflects the source of health changes and is used to represent the process of the fuel cell health status changing from normal to deterioration; (2) PEMFC allows the power limit to reflect health constraints, used to indicate the current SOH Under certain conditions, the PEMFC unit can maintain maximum output capacity for safe and economical operation; (3) The PEMFC reference output power reflects the basic power supply reference and is used to represent the basic load power that it should have undertaken under healthy conditions (assuming 50kW). (4) Power gap Δ P It reflects the power compensation requirement and is used to indicate the output capacity lost by PEMFC due to aging; (5) The gap after the hydrogen supply constraint reflects the hydrogen supply boundary and is used to represent the actual compensation demand that HAICE can bear under the current constraints of ammonia cracking hydrogen supply capacity and hydrogen buffer capacity. (6) The target equivalence ratio mapping reflects the combustion control strategy and is used to represent the target combustion parameters generated by the hybrid system controller for the HAICE unit under the current operating conditions. It reflects the trend of the engine adjusting from the lean combustion region to the stronger power compensation region. (7) The HAICE output lookup table reflects the engine compensation execution, indicating the actual compensation power that the engine can provide under the target equivalence ratio. (8) The fixed power of traditional HAICE reflects the fixed strategy of power compensation. It is used to indicate that under the traditional control strategy, the HAICE unit does not dynamically adjust with the changes in the health status of PEMFC and the hydrogen supply conditions, and always outputs the compensation power according to the preset fixed value (assuming 50kW). (9) The output of the system after collaborative control reflects the total output capability under the strategy of this invention, and is used to represent the sum of the current output of PEMFC and the compensation output of HAICE; (10) The fixed strategy system output reflects the total output capability under the traditional strategy and is used to represent the sum of the current output of PEMFC and the fixed power output of traditional HAICE; (11) The comparison of total system output power reflects the comparison of control effects and is used to indicate the difference in total system output between the collaborative control strategy of the present invention and the traditional fixed strategy under the PEMFC aging conditions.

[0038] The above constitutes the core control chain of this invention, which is passed down step by step from "health status - gap formation - hydrogen supply constraint - combustion regulation - power compensation".

[0039] The criterion for determining whether the current hydrogen supply meets the compensation requirement can be expressed as follows: If the sum of the hydrogen flow rate currently available from the ammonia cracking hydrogen supply unit and the equivalent hydrogen supply capacity currently available from the hydrogen buffer unit is greater than or equal to the target hydrogen supply required by the HAICE unit to compensate for the current power deficit, then the current hydrogen supply is considered to meet the compensation requirement; otherwise, the current hydrogen supply is considered insufficient. The judgment relationship can be expressed as follows:

[0040] , in, This represents the real-time hydrogen supply flow rate of the ammonia cracking unit. The hydrogen buffer unit can release hydrogen flow. The target hydrogen flow rate required to compensate for the current power deficit in the HAICE unit. The power compensation can be calculated based on the current power deficit, the lower heating value of hydrogen, and the equivalent power compensation efficiency of the HAICE unit, or it can be directly obtained from the calibration mapping relationship. Simultaneously, the maximum compensation power that the HAICE unit can support at the current moment can be calculated based on the current hydrogen supply capacity. Then the power gap Δ P and By comparison, the compensable gap Δ after hydrogen supply constraint is obtained. P′ , can be represented as:

[0041] , According to this formula, the actual compensable gap does not exceed the maximum compensation capacity that the HAICE unit can bear under the current hydrogen supply conditions. The compensation gap Δ can be calculated from the current hydrogen supply capacity of ammonia cracking, the release capacity of the hydrogen buffer unit, and the equivalent power compensation efficiency of the HAICE unit under current operating conditions, or determined based on the pre-established correspondence between hydrogen supply capacity and the maximum compensable power of HAICE. For example, if the theoretical power gap in the current simulation verification is 10kW, but the current hydrogen supply capacity only supports an additional 8kW of HAICE compensation, then the compensable gap Δ after the hydrogen supply constraint is... P′ It has a power of 8kW.

[0042] Target equivalence ratio mapping module for compensable gap Δ after hydrogen confinement P′ As input, the target equivalent ratio of the HAICE unit. This is the output. The mapping can be implemented using one-dimensional lookup tables, two-dimensional lookup tables, rule bases, or function mapping methods, and can be represented as:

[0043] Engine speed, load, hydrogen supply status, and emission constraints can also be used as input parameters to establish... Where n is the engine speed and load is the engine load. For hydrogen doping ratio, This refers to the air coefficient. Typically, when the compensable gap after hydrogen supply constraints is small, the HAICE unit can operate in a lean-burn region; as the compensable gap increases, the target equivalence ratio shifts to a region more favorable for power compensation, thereby achieving a coordinated match between power compensation demand, hydrogen supply boundaries, and engine combustion states. The principle for determining the target equivalence ratio mapping relationship is: under the premise of meeting current power compensation demands, to ensure that the HAICE unit operating point is as close as possible to the stable combustion region, and to avoid NO... x The emission risks of NO, NH3Slip, etc., have significantly worsened. Further improvements in emission control capabilities could potentially reduce NO... x NH3Slip is introduced as an additional constraint or correction factor into the target equivalence ratio generation process to further optimize the HAICE combustion state.

[0044] The HAICE output lookup module is used to determine the target equivalent ratio. Obtain the actual compensation power that HAICE can provide. This can be expressed as: , or , The mapping relationship between the target equivalence ratio mapping module and the HAICE output lookup table module can be constructed based on simulation calibration data, engine operating rules in publicly available literature, historical calibration databases, or subsequent calibration data. For the current execution process, simulation calibration data is preferentially used to establish the mapping relationship between the compensable gap after hydrogen supply constraints, the target equivalence ratio, and the HAICE compensation output; if new calibration results are obtained subsequently, this mapping relationship can also be corrected or updated. The input parameters of its mapping relationship include the compensable gap after hydrogen supply constraints, the target equivalence ratio, and engine operating parameters. In addition to the lookup table method, the same function can also be achieved using rule functions, empirical models, or data-driven models. As long as the control process is essentially implemented to dynamically generate the HAICE target equivalence ratio based on the PEMFC health status and hydrogen supply constraints, and further determine the compensation output, it is an optional implementation of this invention.

[0045] Finally, the system output after coordinated control can be expressed as: , The output of a fixed-policy system can be represented as: , in, This represents the fixed compensation power for HAICE under the traditional fixed strategy. (Comparison) and This allows for the evaluation of the compensation effect of the cooperative control method of the present invention relative to the fixed strategy. It should be noted that the comparison of the system output and total system output power under the fixed strategy is mainly used to illustrate the compensation effect of the cooperative control method of the present invention relative to the traditional strategy.

[0046] To verify the effectiveness of the control method of the present invention, Figure 4 A comparison of the system output power after cooperative control (the strategy of this invention) and the system output power under a fixed strategy is presented. Figure 4 It can be seen that when the PEMFC is in normal health, both strategies can maintain the total system output at the rated level. When a PEMFC aging disturbance occurs at a preset time (5s), the PEMFC can allow a power decrease. The fixed strategy, because it does not dynamically correct according to the hydrogen supply constraint and the target equivalence ratio, results in a significant decrease in the total system output. However, the system output after cooperative control (the strategy of this invention) can improve the HAICE unit output according to the hydrogen supply constraint and combustion parameter mapping, thereby significantly reducing the decrease in total power and maintaining a higher level of system output capability. In the current simulation verification, the total system output under the fixed strategy decreased from 100kW to 90kW, while the system output after cooperative control decreased from 100kW to 98kW. Figure 5 and Figure 6 The time-series changes of key power variables and the target equivalence ratio are presented, including the curves showing the changes in PEMFC allowable power, power deficit, target equivalence ratio, and HAICE output. Combining the two figures, it can be seen that when the PEMFC allowable power decreases, the power deficit appears and increases simultaneously; under the constraint of hydrogen supply, the target equivalence ratio adjusts to a region more conducive to power compensation, and the HAICE output increases accordingly, ultimately supporting the system output after coordinated control. This fully demonstrates that the present invention is not simply about "giving the engine more power," but rather achieving compensatory control through the combined action of health status perception, hydrogen supply boundary correction, and combustion parameter adjustment.

[0047] In summary, the present invention has the following technical advantages: (1) This invention integrates the PEMFC health status, the system hydrogen supply feasible domain, the HAICE target equivalence ratio and related constraints into the control framework, thereby improving the integration of hybrid system control.

[0048] (2) The present invention dynamically identifies the output decay based on the health status of PEMFC and combines the hydrogen supply constraint to correct the compensation requirements, thereby helping to avoid unreasonable overload operation of PEMFC and improve the rationality of hydrogen supply coordination.

[0049] (3) In the existing technology, the engine is difficult to adapt to the dynamic changes in power compensation demand and hydrogen supply conditions. By dynamically generating the HAICE target equivalence ratio based on the compensable gap after hydrogen supply constraints, the engine combustion state can be coordinated with the power compensation demand, which is more conducive to maintaining stable combustion and taking into account the emission control requirements of NOx, NH3 and other substances.

[0050] (4) Because the health status, hydrogen supply capacity and combustion control are not uniformly integrated, the system output capacity is prone to decline significantly under the conditions of PEMFC aging and hydrogen supply fluctuation. However, by coordinating the power distribution, hydrogen flow distribution and engine target equivalence ratio of PEMFC and HAICE, the overall output capacity, dynamic adaptability and operational robustness of the hybrid system under complex operating conditions are improved.

[0051] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system, characterized in that, Includes the following steps: The status information of the hybrid system is collected. The hybrid system includes an ammonia storage and supply unit, an ammonia cracking hydrogen supply unit, a hydrogen buffer unit, a PEMFC unit, a HAICE unit, and a hybrid system controller. The current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit is obtained. The current health status of the PEMFC unit is obtained based on the status information, and the current power limit of the PEMFC unit is determined based on the health status. Based on the current power limit of the PEMFC unit and the preset reference output power of the PEMFC unit in a healthy state, the power gap of the PEMFC unit is determined. Based on the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit, the power gap of the PEMFC unit is corrected by hydrogen supply constraint to obtain the compensable gap after hydrogen supply constraint. The compensable gap after the hydrogen supply constraint is input into the preset target equivalent ratio mapping relationship to obtain the target equivalent ratio of the HAICE unit; Based on the target equivalent ratio of the HAICE unit, the actual compensation power of the HAICE unit is obtained through the HAICE output mapping relationship; Based on the actual compensation power of the HAICE unit and the current power limit of the PEMFC unit, the total output power of the system after coordinated control is determined.

2. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 1, characterized in that, The status information of the hybrid system includes: the stack voltage, stack current, output power, temperature and internal resistance characteristic parameters of the PEMFC unit; the outlet hydrogen flow rate, cracking temperature and hydrogen production capacity of the ammonia cracking hydrogen supply unit; the hydrogen storage capacity, pressure and releasable hydrogen flow rate of the hydrogen buffer unit; and the engine speed, load, output power and related operating status parameters of the HAICE unit.

3. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 2, wherein, Obtaining the current health status of the PEMFC unit includes: determining it by monitoring one or more of the characteristics of the PEMFC unit's stack voltage decay, internal resistance growth, and output power decay, or obtaining it based on historical operating data through a health status assessment model.

4. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 1, wherein, Obtaining the compensable gap after the hydrogen supply constraint includes: Based on the status information, it is determined whether the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit meets the requirement of compensating the power gap; if it does, the power gap is taken as the compensable gap after the hydrogen supply constraint; if it does not, the maximum compensation power that the HAICE unit can support at the current moment is determined according to the current hydrogen supply capacity, and the power gap is compared with the maximum compensation power to obtain the smaller value as the compensable gap after the hydrogen supply constraint.

5. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 2, wherein, The preset target equivalence ratio mapping relationship is implemented using one-dimensional lookup table, two-dimensional lookup table, rule base or function mapping method, and the determination principle of the target equivalence ratio mapping relationship includes: under the premise of meeting the current power compensation requirements, the operating point of the HAICE unit is in the stable combustion region, and nitrogen oxide emissions and ammonia escape emissions are constrained.

6. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 5, wherein, The preset target equivalence ratio mapping relationship also takes one or more of the engine speed, load, hydrogen blending ratio and air coefficient of the HAICE unit as additional input parameters, and combines them with the compensable gap after the hydrogen supply constraint to obtain the target equivalence ratio of the HAICE unit.

7. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 1, wherein, The input parameters for the HAICE output mapping relationship include the compensable gap after hydrogen supply constraints, the target equivalence ratio, and engine operating parameters.

8. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 1, wherein, The current power limit of the PEMFC unit is determined according to the following formula: ， wherein is the current upper limit of the power of the PEMFC unit, is the reference output power of the PEMFC unit in a healthy state, is the health state of the PEMFC unit.

9. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 8, wherein, The power gap is determined according to the following formula: ， wherein is the power gap, is the current upper power limit of the PEMFC unit, is the reference output power at the PEMFC unit health state.

10. The hydrogen supply limited health constraint collaborative control method for a PEMFC-HAICE hybrid system according to claim 4, wherein, Whether the current hydrogen supply capacity of the ammonia cracking hydrogen supply unit and the hydrogen buffer unit meets the requirements for compensating the power gap is determined according to the following formula: ， wherein, is the real-time hydrogen supply flow rate of the ammonia cracking hydrogen supply unit, is the releasable hydrogen flow rate of the hydrogen buffer unit, is the target hydrogen flow rate required by the HAICE unit to compensate for the current power gap, which is calculated according to the current power gap, the low heating value of hydrogen, and the equivalent power compensation efficiency of the HAICE unit, or determined by a calibrated power gap-hydrogen demand flow rate mapping relationship. is the target hydrogen flow rate required by the HAICE unit to compensate for the current power gap, which is calculated according to the current power gap, the low heating value of hydrogen, and the equivalent power compensation efficiency of the HAICE unit, or determined by a calibrated power gap-hydrogen demand flow rate mapping relationship.

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