CN-115579490-B - Parameter correction method for solid oxide fuel cell stack model

CN115579490BCN 115579490 BCN115579490 BCN 115579490BCN-115579490-B

Abstract

The invention discloses a parameter correction method of a solid oxide fuel cell stack model. The method comprises the following steps of constructing an output voltage model and a cathode and anode outlet component model, respectively testing output voltages of a fuel cell stack running under different output currents to obtain corresponding I-V discharge curves, dividing each I-V discharge curve, filtering steady-state data in each I-V discharge curve to obtain useful data of each I-V discharge curve, substituting current data in the useful data of each I-V discharge curve into the steady-state model to obtain mole fractions of hydrogen, oxygen and water corresponding to each I-V discharge curve, calculating corresponding partial pressure ratios, substituting the partial pressure ratios into the output voltage model, calculating correction values of various parameters in the output voltage model, and correcting. The invention can accurately correct the model parameters of the solid oxide fuel cell stack and more truly reflect the current characteristics and dynamic information of the solid oxide fuel cell stack.

Inventors

LI ZIYONG
WEI KAIQING
LI ZHUYA
WANG YANTING
HUANG QINGDAN
HUANG HUIHONG
ZHAO CHONGZHI
SONG HAOYONG
LIU JING

Assignees

广东电网有限责任公司广州供电局

Dates

Publication Date: 20260508
Application Date: 20221111

Claims (7)

1. A method for modifying parameters of a solid oxide fuel cell stack model, comprising the steps of: S1, building a solid oxide fuel cell stack model, wherein the solid oxide fuel cell stack model comprises an output voltage model and a cathode and anode outlet component model; S2, adjusting the anode inlet flow and the cathode inlet flow of the solid oxide fuel cell stack to set values, respectively testing the output voltages of the solid oxide fuel cell stack operated under different output currents, and drawing an I-V discharge curve under each output current; s3, dividing each I-V discharge curve, wherein the method comprises the following steps: Dividing data of a section with the voltage fluctuation amplitude smaller than or equal to +/-2% in each I-V discharge curve into steady-state data, and dividing data of a section with the voltage fluctuation amplitude larger than +/-2% in each I-V discharge curve into dynamic data; S4, filtering steady-state data in each I-V discharge curve by adopting a Kalman filtering algorithm to obtain useful data of each I-V discharge curve; s5, converting the cathode and anode outlet component model into a steady-state model, substituting current data in useful data of each I-V discharge curve into the steady-state model to obtain mole fractions of hydrogen, oxygen and water corresponding to each I-V discharge curve, and calculating a corresponding partial pressure ratio; S6, substituting the useful data and the partial pressure ratio corresponding to each I-V discharge curve into the output voltage model, calculating the correction value of each parameter in the output voltage model, and assigning each parameter as the corresponding correction value.
2. The method for correcting parameters of a solid oxide fuel cell stack model according to claim 1, wherein the formula of the output voltage model in step S1 is as follows: Wherein V is the output voltage of the solid oxide fuel cell stack, N cell is the number of cells of the solid oxide fuel cell stack, I is the output current of the solid oxide fuel cell stack, T s is the stack temperature, R is the gas constant, F is the Faraday constant, The hydrogen partial pressure, the oxygen partial pressure and the water partial pressure in the solid oxide fuel cell stack are respectively, T 0 is room temperature, z is the mole number of reaction electrons, C re is the concentration of hydrogen, E 0 、k E is the empirical constant of the Nernst electromotive force, delta and gamma are the empirical constant of ohmic resistance of the solid oxide fuel cell stack, k 1 、k 2 is the empirical constant of exchange current, and k 3 is the empirical constant of limiting current.
3. The method for correcting parameters of a solid oxide fuel cell stack model according to claim 1, wherein the formula of the cathode and anode outlet component model in the step S1 is as follows: i∈{CO,CO 2 ,H 2 ,H 2 O,O 2 ,N 2 }, Where N is the molar weight of the mixed fluid composed of all reactants, C 10,i is the molar fraction of the i-reactant at the anode outlet of the solid oxide fuel cell stack, C 12,i is the molar fraction of the i-reactant at the cathode outlet of the solid oxide fuel cell stack, F 9 is the anode inlet flow of the solid oxide fuel cell stack, F 11 is the cathode inlet flow of the solid oxide fuel cell stack, C 9,i is the molar fraction of the i-reactant at the anode inlet of the solid oxide fuel cell stack, C 11,i is the molar fraction of the i-reactant at the cathode inlet of the solid oxide fuel cell stack, F 10 is the anode outlet flow of the solid oxide fuel cell stack, F 12 is the cathode outlet flow of the solid oxide fuel cell stack, The stoichiometric coefficient of the reactant i in the reaction of j 1 , The stoichiometric coefficient of the reactant i in the reaction of j 2 , Is the reaction rate of the anode electrochemical reaction of the solid oxide fuel cell stack, The reaction rate is the reaction rate of the cathode electrochemical reaction of the solid oxide fuel cell stack, OR is the oxidation reaction, RR is the reduction reaction, F is the Faraday constant, N cell is the number of the cells of the solid oxide fuel cell stack, and I is the output current of the solid oxide fuel cell stack.
4. A method for modifying parameters of a solid oxide fuel cell stack model according to claim 1,2 or 3, wherein the test time for testing the output voltage of the solid oxide fuel cell stack at each output current in step S2 is not less than t1 minutes, and the interval between adjacent tests is not less than t2 minutes.
5. A method for modifying parameters of a solid oxide fuel cell stack model according to claim 3, wherein the method for converting the cathode and anode outlet component model to a steady state model is as follows: In the outlet component model of the cathode and the anode All are set to 0, and a steady-state model is obtained, wherein the steady-state model has the following formula: i∈{CO,CO 2 ,H 2 ,H 2 O,O 2 ,N 2 }。
6. the method for correcting parameters of a solid oxide fuel cell stack model according to claim 5, wherein the formula for calculating the corresponding partial pressure ratio according to the mole fractions of hydrogen, oxygen and water corresponding to a certain I-V discharge curve in step S5 is as follows: Wherein, the Respectively the hydrogen partial pressure, the oxygen partial pressure and the water partial pressure in the solid oxide fuel cell stack, Is the mole fraction of hydrogen at the anode outlet of the solid oxide fuel cell stack, Is the mole fraction of water at the anode outlet of the solid oxide fuel cell stack, Is the mole fraction of oxygen at the cathode outlet of the solid oxide fuel cell stack.
7. A method for modifying parameters of a solid oxide fuel cell stack model according to claim 1,2 or 3, wherein the correction values of the respective parameters in the output voltage model are calculated in step S6 by using a particle swarm optimization algorithm.

Description

Parameter correction method for solid oxide fuel cell stack model Technical Field The invention relates to the technical field of fuel cells, in particular to a parameter correction method of a solid oxide fuel cell stack model. Background The Solid Oxide Fuel Cell (SOFC) is the fuel cell technology with highest power generation efficiency at present, has the characteristics of wide fuel applicability, high waste heat quality, low maintenance cost, reversible operation and the like, and has great application prospect in the field of the current power generation system. With the growing widespread use of SOFCs, the importance of designing, simulating, analyzing and developing efficient fuel cell systems is increasingly highlighted, wherein the problem of accurate modeling of the fuel cell system core element stacks is increasingly emphasized. At present, the construction of a solid oxide fuel cell stack model is mainly based on two major categories of a mechanism analysis method and a testing method. However, the various process structures and the complex thermal, gas and electrical mechanisms of SOFCs are difficult to describe accurately, which brings certain difficulties to the establishment of the mechanism model. The test rule requires a large amount of experimental data, is limited by the hardware and the operation condition of an actual system, and the perfect data acquisition can face great difficulty. Disclosure of Invention In order to solve the technical problems, the invention provides a parameter correction method of a solid oxide fuel cell stack model, which realizes accurate correction of the solid oxide fuel cell stack model parameters through limited experimental test data and reflects current characteristics and dynamic information of the solid oxide fuel cell stack more truly. In order to solve the problems, the invention is realized by adopting the following technical scheme: The invention relates to a parameter correction method of a solid oxide fuel cell stack model, which comprises the following steps: S1, building a solid oxide fuel cell stack model, wherein the solid oxide fuel cell stack model comprises an output voltage model and a cathode and anode outlet component model; S2, adjusting the anode inlet flow and the cathode inlet flow of the solid oxide fuel cell stack to set values, respectively testing the output voltages of the solid oxide fuel cell stack operated under different output currents, and drawing an I-V discharge curve under each output current; s3, dividing each I-V discharge curve, wherein the method comprises the following steps: Dividing data of a section with the voltage fluctuation amplitude smaller than or equal to +/-2% in each I-V discharge curve into steady-state data, and dividing data of a section with the voltage fluctuation amplitude larger than +/-2% in each I-V discharge curve into dynamic data; S4, filtering steady-state data in each I-V discharge curve by adopting a Kalman filtering algorithm to obtain useful data of each I-V discharge curve; s5, converting the cathode and anode outlet component model into a steady-state model, substituting current data in useful data of each I-V discharge curve into the steady-state model to obtain mole fractions of hydrogen, oxygen and water corresponding to each I-V discharge curve, and calculating a corresponding partial pressure ratio; S6, substituting the useful data and the partial pressure ratio corresponding to each I-V discharge curve into the output voltage model, calculating the correction value of each parameter in the output voltage model, and assigning each parameter as the corresponding correction value. In the scheme, a solid oxide fuel cell stack model is firstly constructed, then output voltages of the solid oxide fuel cell stack running under a plurality of different output currents are tested, I-V discharge curves under the output currents are collected, the I-V discharge curves under each output current are processed to obtain useful stable data in the I-V discharge curves under each output current, the useful stable data are substituted into the steady-state model, the mole fractions of hydrogen, oxygen and water corresponding to each I-V discharge curve are calculated, corresponding partial pressure ratios are calculated, finally the data are substituted into the output voltage model, correction values of all parameters in the output voltage model are calculated, and all the parameters are assigned to corresponding correction values, so that the solid oxide fuel cell stack model can reflect real current characteristics and dynamic information of the solid oxide fuel cell stack. Preferably, the output voltage model in the step S1 has the following formula: Wherein V is the output voltage of the solid oxide fuel cell stack, N cell is the number of cells of the solid oxide fuel cell stack, I is the output current of the solid oxide fuel cell stack, T s is the stack temperature, R is the gas consta