CN-122025705-A - Thermoelectric cooperative control method and system for fuel cell based on methanol reforming hydrogen production

CN122025705ACN 122025705 ACN122025705 ACN 122025705ACN-122025705-A

Abstract

The invention discloses a thermoelectric cooperative control method and a thermoelectric cooperative control system for a fuel cell based on methanol reforming, which belong to the field of fuel cell control, wherein the control method comprises the steps of acquiring a real-time operation parameter set of a fuel cell system, calculating a theoretical hydrogen consumption rate of a galvanic pile anode based on a galvanic pile instantaneous current and a preset Faraday electrolysis mathematical equation, and performing algebraic mapping calculation to generate transient heat mismatch quantity of a reformer; and synchronously outputting a first control instruction and a second control instruction through a hardware control interface according to the transient heat mismatch amount. The invention does not need to rely on an online identification algorithm, a neural network or frequent manual recalibration, so that the feedforward control model can maintain good control precision at each stage of the full life cycle of the equipment.

Inventors

Xue Zengyi
XU JIE
Zhai Shouqing
DONG XIAOLONG
WANG HONGHUI

Assignees

四川蓉氢科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. A thermoelectric cooperative control method for a fuel cell based on methanol reforming hydrogen production is characterized in that the thermoelectric cooperative control method comprises the following steps of, A real-time set of operating parameters of the fuel cell system is acquired, The real-time operation parameter set at least comprises a galvanic pile instantaneous current, a current wall surface temperature of the reformer, a total methanol liquid inlet flow and a total flow of reformed gas entering the galvanic pile; Calculating theoretical hydrogen consumption rate of the anode of the electric pile based on the electric pile instantaneous current and a preset Faraday electrolysis mathematical equation, and Performing difference operation on the hydrogen partial pressure flow in the total flow of the reformed gas and the theoretical hydrogen consumption rate, and multiplying the difference operation by a fixed hydrogen low-order heating value constant to generate real-time tail gas heating value data representing the energy of unreacted hydrogen in the anode tail gas; Inputting the current change rate of the current of the galvanic pile, the current wall temperature of the reformer and the real-time tail gas heat value data into a preset current-hydrogen production-waste heat needed solution coupling model to perform algebraic mapping calculation, and generating the transient heat mismatch quantity of the reformer; According to the transient heat loss amount, synchronously outputting a first control instruction and a second control instruction through a hardware control interface, The first control instruction is used for driving a proportional three-way valve arranged at the discharge end of the anode tail gas to adjust the mixing proportion of the tail gas entering the combustion chamber, The second control command is used for driving an auxiliary methanol afterburner pump to adjust the amount of auxiliary methanol afterburner directly entering the combustion chamber.
2. The method for the coordinated control of thermoelectricity of a hydrogen production fuel cell based on methanol reforming as claimed in claim 1, wherein the total flow of reformed gas is directly measured by a dual channel mass flow controller before entering the stack, and The dual-channel mass flow controller is connected with the proportional three-way valve through the same hardware control bus, and the real-time operation parameter set and the first control instruction are synchronously received and transmitted by adopting a deterministic time division multiplexing protocol.
3. The method for the coordinated control of thermoelectricity of a hydrogen production fuel cell based on methanol reforming according to claim 1, wherein the step of calculating a theoretical hydrogen consumption rate of the anode of the stack comprises: Acquiring the total number of single cell pieces of a galvanic pile; Acquiring the current of the electric pile at the current sampling moment; Dividing the product of the total number of the single cell pieces and the instant current of the electric pile by the product of Faraday constant and the number of electrons transferred by hydrogen per mole to obtain the theoretical hydrogen consumption rate.
4. The method of thermal and electrical cooperative control of a methanol reforming based hydrogen production fuel cell of claim 1, wherein the step of generating real-time tail gas heating value data indicative of unreacted hydrogen energy in the anode tail gas comprises: Multiplying the total flow of the reformed gas by the mole fraction of hydrogen to obtain the total supply mole flow of hydrogen currently entering the anode of the electric pile; Subtracting the theoretical hydrogen consumption rate from the total hydrogen supply molar flow to obtain the molar flow of unreacted hydrogen in the anode tail gas; And multiplying the molar flow of the unreacted hydrogen by the physical heat recovery efficiency constant of the tail gas pipeline and multiplying the fixed hydrogen low-order heating value constant to obtain the real-time tail gas heat value data.
5. The method for the coordinated control of thermoelectricity of a hydrogen fuel cell based on methanol reforming as in claim 4, further comprising a boundary anomaly handling step, prior to said step of generating real-time tail gas heating value data indicative of unreacted hydrogen energy in the anode tail gas: comparing the average voltage of the single cell of the electric pile obtained at the current moment with a theoretical voltage corresponding to the instant current of the electric pile in a pre-stored standard polarization curve; And if the average voltage of the single cells of the electric pile is lower than the theoretical voltage by more than a preset difference value, and the real-time tail gas heat value data indicate that sufficient unreacted hydrogen exists in the anode tail gas, judging that a flooding working condition occurs in the electric pile.
6. The method for the coordinated control of thermoelectricity of a methanol reforming based hydrogen production fuel cell of claim 5, further comprising, after determining that the flooding condition occurs inside the stack: Forcibly suspending the subsequent algebraic map calculation step and the step of synchronously outputting a first control instruction and a second control instruction; commanding an exhaust electromagnetic valve arranged at the exhaust end of the anode tail gas to alternately execute full-opening and full-closing actions at a frequency of more than 10 Hz, and triggering a pulse purging time sequence; and continuously monitoring the average voltage of the electric pile single cells until the average voltage of the electric pile single cells is recovered to be within the preset difference range corresponding to the theoretical voltage in the standard polarization curve, releasing the suspension state, and recovering to execute the algebraic mapping calculation step and the step of synchronously outputting a first control command and a second control command.
7. The method for the coordinated control of thermoelectricity of a fuel cell based on the reforming of methanol to produce hydrogen according to claim 1, characterized in that said step of generating a transient heat mismatch amount of said reformer comprises: Calculating the current change rate of the pile instantaneous current in three continuous sampling periods through a first-order backward differential algorithm; Mapping the current change rate of the transient current of the electric pile into a target hydrogen production increment in a next time window through a preset ratio conversion coefficient, and converting the target hydrogen production increment into feedforward heat absorption demand power according to a molar heat absorption enthalpy change constant of a methanol steam reforming reaction; and extracting a thermal inertia damping coefficient calibrated in advance based on the specific heat capacity of the structural member of the reformer, subtracting the real-time tail gas heat value data from the feedforward heat absorption required power, and multiplying the thermal inertia damping coefficient to obtain the transient heat loss.
8. The thermoelectric cooperative control method of a fuel cell based on methanol reforming hydrogen production according to claim 1, wherein the current-hydrogen yield-waste heat needed solution coupling model is implemented in the form of a static multidimensional search matrix compiled in a read-only memory, and the algebraic mapping calculation specifically comprises the steps of: Mapping the quantized current change rate of the pile instantaneous current into a row index vector of the static multidimensional search matrix; mapping the current wall temperature of the reformer into a column index vector of the static multidimensional search matrix after quantization; Mapping the quantized real-time tail gas heat value data into a depth index vector of the static multidimensional search matrix; and addressing and extracting a corresponding pre-calculated value from the static multidimensional search matrix to serve as the transient heat mismatch amount according to a three-dimensional index coordinate formed by the row index vector, the column index vector and the depth index vector.
9. The method for controlling a hydrogen production fuel cell based on methanol reforming according to claim 1, wherein in the step of synchronously outputting the first control command and the second control command according to the transient heat mismatch amount, according to a numerical interval in which the transient heat mismatch amount is located, the following mutually exclusive operating mode branches are executed: When the transient heat loss amount is positive and is larger than a first preset threshold value, judging that the load is in a sudden increase working condition; And when the transient heat loss amount is a negative value and the absolute value is larger than a second preset threshold value, judging that the load suddenly drops.
10. A thermoelectric cooperative control system for a fuel cell based on methanol reforming hydrogen production, the thermoelectric cooperative control system comprising: A processor; a memory storing a computer program which, when executed by a processor, implements the thermoelectric cooperative control method based on a methanol reforming hydrogen production fuel cell as defined in any one of claims 1 to 9.

Description

Thermoelectric cooperative control method and system for fuel cell based on methanol reforming hydrogen production Technical Field The invention relates to the field of fuel cell control, in particular to a thermoelectric cooperative control method and a thermoelectric cooperative control system for a fuel cell based on methanol reforming hydrogen production. Background The methanol reforming hydrogen production fuel cell system takes a methanol aqueous solution as a raw material, generates hydrogen-rich reformed gas in situ through a methanol steam reforming reaction in a reformer, and supplies the hydrogen-rich reformed gas to a proton exchange membrane fuel cell stack for electrochemical power generation. Since the reforming reaction is a strongly endothermic process, the system needs to continuously supply heat to the reformer to maintain the normal progress of the reaction. In the prior art, the heat required by the reformer mainly comes from two parts, namely catalytic combustion heat release of residual hydrogen in tail gas discharged from the anode of the electric pile in a combustion chamber and supplementary combustion heat release of auxiliary methanol in the combustion chamber. Maintaining the dynamic balance between the heat supply amount and the heat absorption amount of the reforming reaction is a key for ensuring the safe and efficient operation of the system. However, existing control schemes suffer from the following disadvantages: On the one hand, the available heat value carried by the residual hydrogen in the anode tail gas lacks a real-time accurate quantification means, and is generally only estimated empirically according to a preset fixed proportion, and when the working condition of the system deviates from the standard point, the error between the estimated value and the true value is obviously increased, so that the subsequent heat distribution decision is based on distorted data. On the other hand, a feedback control mode based on a temperature sensor is generally adopted for adjusting the heat demand change of the reformer. Because the reformer structural member has larger thermal inertia, obvious time delay exists between the change of load and the detection of temperature deviation by the temperature sensor, the control action is seriously delayed from the actual demand change, and the over-temperature of the catalyst bed layer of the reformer or the insufficient supply of hydrogen is easily caused under the abrupt load condition. Disclosure of Invention The invention aims to provide a thermoelectric cooperative control method for a fuel cell for hydrogen production based on methanol reforming, which aims to solve the problems that in the prior art, available heat value of anode tail gas can only be estimated through proportional experience and cannot be accurately quantified in real time, meanwhile, the regulation of heat demand change of a reformer depends on temperature feedback control and is limited by thermal inertia of a structural member of the reformer, control actions are seriously delayed from actual demand change, reforming-combustion heat balance is damaged when load is suddenly changed, and catalyst bed overtemperature or hydrogen starvation is caused. The invention discloses a thermoelectric cooperative control method of a fuel cell based on methanol reforming, which comprises the following steps of obtaining a real-time operation parameter set of a fuel cell system, wherein the real-time operation parameter set at least comprises a current wall temperature of a galvanic pile, a total methanol feed-in flow and a total flow of reformed gas entering the galvanic pile, calculating a theoretical hydrogen consumption rate of an anode of the galvanic pile based on the current wall temperature of the galvanic pile, the total methanol feed-in flow and a preset Faraday electrolysis mathematical equation, performing difference operation on a hydrogen partial pressure flow in the total flow of the reformed gas and the theoretical hydrogen consumption rate, multiplying a fixed hydrogen low-level heating value constant to generate real-time tail gas heating value data representing unreacted hydrogen energy in tail gas of the anode, inputting the current change rate of the current wall temperature of the galvanic pile, the current wall temperature of the galvanic pile and the real-time tail gas heating value data into a preset current-hydrogen production quantity-waste heat required solution coupling model to perform algebraic mapping calculation, generating the transient heat quantity of the galvanic pile, synchronously outputting a first control instruction and a second control instruction through a hardware control interface according to the transient heat loss quantity, and driving a methanol complementary combustion control instruction to enter a methanol complementary combustion chamber of the first control instruction to enter a three-way combustion auxiliary proporti