CN116314969B - Fuel starvation diagnosis and air supply configuration method for SOFC system - Google Patents
Fuel starvation diagnosis and air supply configuration method for SOFC system Download PDFInfo
- Publication number
- CN116314969B CN116314969B CN202310110927.XA CN202310110927A CN116314969B CN 116314969 B CN116314969 B CN 116314969B CN 202310110927 A CN202310110927 A CN 202310110927A CN 116314969 B CN116314969 B CN 116314969B
- Authority
- CN
- China
- Prior art keywords
- fuel
- fuel cell
- current
- starvation
- curve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000000446 fuel Substances 0.000 title claims abstract description 201
- 235000003642 hunger Nutrition 0.000 title claims abstract description 74
- 230000037351 starvation Effects 0.000 title claims abstract description 74
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000003745 diagnosis Methods 0.000 title claims abstract description 18
- 239000007787 solid Substances 0.000 claims abstract description 49
- 239000002737 fuel gas Substances 0.000 claims abstract description 37
- 238000012360 testing method Methods 0.000 claims abstract description 34
- 238000001514 detection method Methods 0.000 claims abstract description 9
- 230000000630 rising effect Effects 0.000 claims description 7
- 238000004832 voltammetry Methods 0.000 claims description 7
- 239000007789 gas Substances 0.000 claims description 5
- 238000001566 impedance spectroscopy Methods 0.000 claims description 5
- 230000003247 decreasing effect Effects 0.000 claims description 4
- 238000011156 evaluation Methods 0.000 abstract description 6
- 210000004027 cell Anatomy 0.000 description 128
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 15
- 229910052739 hydrogen Inorganic materials 0.000 description 13
- 239000001257 hydrogen Substances 0.000 description 13
- 238000001453 impedance spectrum Methods 0.000 description 4
- 239000012528 membrane Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04992—Processes for controlling fuel cells or fuel cell systems characterised by the implementation of mathematical or computational algorithms, e.g. feedback control loops, fuzzy logic, neural networks or artificial intelligence
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
- H01M8/04537—Electric variables
- H01M8/04544—Voltage
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
- H01M8/04537—Electric variables
- H01M8/04544—Voltage
- H01M8/04552—Voltage of the individual fuel cell
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
- H01M8/04537—Electric variables
- H01M8/04574—Current
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04298—Processes for controlling fuel cells or fuel cell systems
- H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
- H01M8/04537—Electric variables
- H01M8/04574—Current
- H01M8/04582—Current of the individual fuel cell
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
- H01M8/124—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte
- H01M8/1246—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte characterised by the process of manufacturing or by the material of the electrolyte the electrolyte consisting of oxides
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Electrochemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Chemical & Material Sciences (AREA)
- Sustainable Energy (AREA)
- Sustainable Development (AREA)
- Computing Systems (AREA)
- Theoretical Computer Science (AREA)
- Software Systems (AREA)
- Medical Informatics (AREA)
- Fuzzy Systems (AREA)
- Evolutionary Computation (AREA)
- Health & Medical Sciences (AREA)
- Automation & Control Theory (AREA)
- Artificial Intelligence (AREA)
- Fuel Cell (AREA)
Abstract
The invention discloses a fuel starvation diagnosis and air supply configuration method of an SOFC system, which comprises the steps of placing a solid oxide fuel cell in a high-temperature test furnace, maintaining a high-temperature test environment, supplying air to a cathode of the fuel cell and fuel gas to an anode of the fuel cell, and measuring a current-voltage curve of the whole fuel cell system by using an electronic load; measuring a solid oxide fuel cell local area voltage signal using a multi-channel voltmeter; calculating a current-area resistance (I-ASR) curve of the fuel cell; and diagnosing whether the fuel starvation phenomenon exists in the part of the solid oxide fuel cell according to the upwarp phenomenon of the resistor on the obtained I-ASR curve. The invention can amplify the fuel starvation condition of the local cell unit of the measurable fuel cell stack, reduce the local fuel starvation condition of the detectable single cell piece, and finally obtain the fuel starvation diagnosis method of the fuel cell system, which has steady evaluation index and can carry out local detection.
Description
Technical Field
The invention relates to the technical field of SOFC system operation and maintenance, in particular to a SOFC system fuel starvation diagnosis and air supply configuration method.
Background
Among the many types of fuel cells, solid oxide fuel cells (solid Oxide Fuel Cell, SOFC) have an all-ceramic solid structure, and can directly use carbon-based fuels, which are the type of fuel cells with the widest application prospect. In practical application, to increase output power, a plurality of SOFCs are required to be connected in series to form a stack, and then the stacks are assembled in series and parallel to form a module. In the series-parallel connection process, the non-uniformity of the gas distribution pipeline can cause non-uniformity of gas distribution. In actual operation, carbon deposition on the pipelines and the battery electrodes can also cause non-uniform gas distribution. The maldistribution in each of the above cases will be manifested as fuel starvation of the fuel cell electrical signal. Fuel starvation will cause cell anode oxidation, accelerate degradation of cell performance, and shorten fuel cell life.
Current SOFC fuel air supply configurations are mainly achieved by controlling fuel utilization: and setting an upper limit of fuel utilization rate for the fuel cell by means of current-voltage measured curve data of a single cell or a single cell stack sample, and keeping the fuel utilization rate not to exceed the limit in the operation of the fuel cell. Chinese patent CN103413955a discloses a control method for preventing the fuel utilization of a solid oxide fuel cell from overrun, which prevents the overrun from occurring by controlling the deviation between the output voltage value of the fuel cell system and the set value thereof; chinese patent CN115064741a discloses a method for calculating fuel utilization rate of fuel cell based on internal resistance model, which improves convenience and accuracy in calculating fuel utilization rate; chinese patent CN107464944a discloses a fuel cell system and a method of operating the same, measuring fuel flow, current and circulation ratio to estimate fuel utilization. Chinese patent CN101378130a discloses a method of driving a fuel cell device, controlling fuel utilization by detecting fuel outlet concentration and load current. The limitation of such methods is that the fuel utilization rate is an integral index of the fuel cell system, and the upper limit of the fuel utilization rate changes with the increase of the number of fuel cell sheets and the complexity of the system air supply pipeline. In addition, the fuel utilization rate as an overall index cannot avoid the occurrence of local fuel starvation, and direct experimental diagnosis of whether fuel supply of the fuel cell system is sufficient is one of the technologies to be broken through currently.
According to related patent reports at home and abroad, the diagnosis of fuel starvation is mainly realized through electric signal detection, and the diagnosis can be particularly divided into two major categories, namely impedance spectroscopy and voltammetry. With the aid of impedance spectroscopy, chinese patent CN109726452B, CN110676488A, CN113540534A, CN114899457A, CN115084593a reports a proton exchange membrane fuel cell fault diagnosis method, and part of the disclosure relates to a fuel starvation diagnosis method. The impedance spectrum method mainly realizes impedance detection by detecting the electric signal of the tested element under a series of frequency alternating current signals, and under each test frequency, a test system needs to meet good linear feedback characteristics so as to ensure the accuracy of impedance spectrum test. However, fuel cells in a fuel starved state will experience severe concentration polarization, resulting in non-linear enhancement of the system, which greatly increases the difficulty of impedance spectroscopy testing. In practical application, the impedance spectrum of the fuel cell in the fuel starvation state has poor repeatability, and the data has larger discreteness, so that the reliability of the impedance spectrum method is reduced. Compared with the prior art, the voltammetry has the advantages of low test cost, single test frequency, simple experimental operation, stable test data and low requirement on the linear characteristic of a test system: US patent 20190386323A1 discloses a method of detecting a fuel starvation condition of a fuel cell system by detecting the amplitude of fluctuations in an output electrical signal; US patent 2012028152A1 discloses a method for diagnosing and correcting the partial pressure of the low hydrogen concentration at the anode of a proton exchange membrane fuel cell system, in particular by detecting the change of the minimum voltage of the cell caused by the change of the anode pressure; furthermore, U.S. patent No. 9231263B2 discloses a method of distinguishing cathode and anode fuel starvation by detecting the rate of voltage drop based on the objective fact that the cathode voltage drop is slower than the anode when fuel starvation occurs with a proton exchange membrane fuel cell cathode noble metal catalyst loading greater than the anode. The limitation of the detection method is that setting the voltage signal as the control reference threshold value faces the problem that the judgment index has large fluctuation: even for the same type of fuel cells, the voltage deviation of fuel starvation of the fuel cells under different fuel supply amounts can reach more than 20%. Based on the above, the wide application of the voltammetry needs to invent a more robust evaluation index.
Disclosure of Invention
The invention aims to provide a fuel starvation diagnosis and air supply configuration method of an SOFC system with a steady evaluation index based on a voltammetry.
In order to achieve the above purpose, the invention provides a fuel starvation diagnosis and air supply configuration method of an SOFC system based on voltammetry, which comprises the following steps:
placing the solid oxide fuel cell in a 650-900 ℃ high-temperature test furnace, and maintaining a high-temperature test environment;
the cathode of the solid oxide fuel cell supplies air and the anode supplies fuel gas;
measuring a current-voltage curve (I-V curve) of the solid oxide fuel cell system as a whole using an electronic load based on voltammetry;
measuring a solid oxide fuel cell local area voltage signal using a multi-channel voltmeter;
determining a local area I-V curve based on the I-V curve of the whole solid oxide fuel cell and the voltage signal of the local area measured by the multi-channel voltmeter;
based on the local area I-V curve, calculating a current-area resistance (I-ASR) curve of the local area, wherein the area resistance is equivalent to the impedance of the fuel cell detected by an impedance spectroscopy at ultralow frequency, and is regarded as a kind of steady evaluation index in the invention;
and diagnosing whether the fuel starvation phenomenon exists in the part of the solid oxide fuel cell according to the rising of the upper resistor of the obtained I-ASR curve.
As a further scheme of the invention: the solid oxide fuel cell is provided with a voltage local detection point which is connected with a voltage connector of the multichannel voltmeter through a local voltage lead; the cathode of the solid oxide fuel cell is connected with a current testing joint of an electronic load through a current lead; the anode of the solid oxide fuel cell is connected to a voltage test connection of an electronic load via a voltage lead.
As a further scheme of the invention: an air inlet pipeline is arranged at the cathode of the solid oxide fuel cell, the air inlet pipeline is positioned above the cathode, the air outlet pipeline is arranged at one side of the cathode, and a current wire joint is connected at the other side of the cathode; a fuel gas inlet pipeline is arranged above the anode of the solid oxide fuel cell, a fuel gas outlet pipeline is arranged on one side of the anode, and a voltage connector is connected to the other side of the anode.
As a further aspect of the invention: the air inlet pipeline and the fuel gas inlet pipeline of the solid oxide fuel cell are respectively filled with quantitative air and fuel gas, namely, sufficient air and fuel gas are firstly obtained, namely, the condition that starvation phenomenon does not exist is avoided, then the air flow is reduced for a plurality of times in a proper amount, then the air flow returns to a proper amount, and the fuel gas flow is reduced for a plurality of times in a proper amount.
As a further aspect of the invention: the flow rates of air and fuel gas are controlled by a flow meter.
As a further aspect of the invention: firstly, determining an I-ASR curve when air and fuel gas are sufficient, setting the I-ASR curve as a standard curve, and observing that the resistor on the standard curve cannot warp upwards in a high-current discharge state; then comparing the I-ASR curve of other conditions with a standard curve, and observing that the resistance on the curve rises suddenly along with the increase of the current to generate a rising phenomenon, wherein the smaller the air supply flow is, the smaller the current of rising of the surface resistance is; the face resistance upturned is used as a criterion for the occurrence of fuel starvation, whether the fuel cell has the fuel starvation or not is diagnosed, and the obvious fuel starvation is started when the current under different air supply flows is determined.
As a further aspect of the invention: the solid oxide fuel cell includes a monolithic cell, a split cell, and a stack.
As a further aspect of the invention: the split cell is formed by splitting a solid oxide cell into a plurality of areas, and determining whether the split cell has a fuel starvation phenomenon by detecting whether each area has the fuel starvation phenomenon.
As a further aspect of the invention: the cell stack is formed by connecting a plurality of fuel cell units in series, and whether the fuel starvation phenomenon of the cell stack occurs can be determined by directly detecting whether the fuel starvation occurs in different cell units.
As a further aspect of the invention: in the actual operation of the solid oxide fuel cell system, if the surface resistance threshold value of the fuel cell is known, on the basis of the normal operation current of the fuel cell system, a plurality of tiny current step sizes are appropriately increased and decreased, the voltage value under the corresponding current is measured, the surface resistance of the fuel cell under the current operation current is calculated based on the current value and the voltage value and is compared with the surface resistance threshold value, if the surface resistance actual measurement value is larger than the threshold value, the system is in a fuel starvation state, otherwise, the system fuel supply is sufficient; if the surface resistance threshold is unknown, the surface resistance of the battery close to a plurality of operation current values can be measured, the surface resistance is upwarp as a criterion for the occurrence of fuel starvation, if the surface resistance is upwarp along with the increase of the current, the system is in a fuel starvation state, otherwise, the system fuel supply is sufficient.
Compared with the prior art, the invention has the following beneficial effects: the invention provides a fuel starvation diagnosis and air supply configuration method of an SOFC system, which takes a robust fuel cell surface resistance with intrinsic properties as a fuel starvation evaluation index, calculates an I-V curve of a corresponding local area by measuring voltage signals of the whole I-V curve and the local area of the SOFC, further obtains an I-ASR curve of the corresponding local area, takes the upturned surface resistance as a robust criterion of fuel starvation, diagnoses whether the SOFC is wholly and locally starved, and quantifies the starvation degree. According to the technical scheme, the fuel starvation condition of the local cell units of the fuel cell stack can be measured, the local fuel starvation condition of a single cell piece can be detected in a reduced mode, and finally the fuel starvation diagnosis and air supply configuration method of the fuel cell system, which is stable in evaluation index and capable of carrying out local detection, is obtained.
Drawings
Fig. 1 is a schematic view of the structure of an integrated fuel cell diagnostic device of the present invention.
Fig. 2 is a schematic diagram of the cathode supply of a solid oxide fuel cell in accordance with the present invention.
Fig. 3 is a schematic view of the anode supply of a solid oxide fuel cell of the present invention.
FIG. 4 is a graph of I-ASR for an integrated fuel cell of the present invention with a different anode hydrogen supply versus a fixed cathode air supply.
Fig. 5 is an I-ASR graph of a fuel cell with a difference in the cathode air intake fixed anode hydrogen intake for an overall fuel cell of the present invention.
Fig. 6 is a schematic view of a split battery in the present invention.
Fig. 7 is a schematic view of the structure of the split battery diagnosis apparatus in the present invention.
FIG. 8 is a graph of I-ASR for dividing cell region one in accordance with the present invention.
FIG. 9 is a graph of I-ASR for dividing cell region two in the present invention.
FIG. 10 is a graph of I-ASR for dividing cell region three in the present invention.
FIG. 11 is a graph of I-ASR for dividing cell region four in the present invention.
Fig. 12 is a schematic view of the structure of a fuel cell diagnosis device for a cell stack according to the present invention.
FIG. 13 is a graph of the I-ASR for cell three in the present invention.
FIG. 14 is a graph of the I-ASR for cell five in the present invention.
FIG. 15 is a graph of the I-ASR for cell six in the present invention.
In the figure: 1. a high temperature test furnace 2, a voltage local detection point 3, a current wire connector 4, a voltage wire connector 5, a local voltage lead 6, a current lead 7, a voltage lead 8, a voltage test connector 9, a current test connector 10, a voltage connector 11, a multichannel voltmeter 12, an electronic load 13, a solid oxide fuel cell 14, an air inlet pipeline, 15 air outlet duct, 16, cathode, 17, fuel gas inlet duct, 18, fuel gas outlet duct, 19, anode, 20, zone one, 21, zone two, 22, zone three, 23, zone four, 24, stack, 25, cell six, 26, cell five, 27, cell four, 28, cell three, 29, cell two, 30, cell one.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
1. Integral battery testing principle
Step 1, as shown in fig. 1, the whole solid oxide fuel cell 13 is placed in a high temperature test furnace 1, and a corresponding and appropriate high temperature test environment is maintained, wherein a temperature of 720 ℃ is taken.
Step 2, as shown in fig. 2, an air inlet pipe 14 is provided at a cathode 16 of the solid oxide fuel cell 13, the air inlet pipe 14 is located above the cathode 16 for supplying air, an air outlet pipe 15 is provided at one side of the cathode 16, and a current wire connector 3 is connected at the other side of the cathode 16; as shown in fig. 4, a fuel gas inlet pipe 17 for supplying fuel gas is provided above an anode 19 of the solid oxide fuel cell 13, a fuel gas outlet 18 for outputting fuel gas is provided on one side of the anode 19, and a voltage line terminal 4 is connected to the other side of the anode 19; the flow rates of air and fuel gas are controlled by a flow meter.
Step 3, as shown in fig. 1, the current lead 6 and the voltage lead 7 are connected to the current test terminal 9 and the voltage test terminal 8 of the electronic load 12 in the low temperature region, respectively, at the cathode current lead 3 and the anode voltage lead 4 of the solid oxide fuel cell 13. The electronic load 12 here can measure the current-voltage characteristic (I-V curve) of the battery as a whole; according to the measured I-V curve, the resistance value R corresponding to the output current Ii of the whole battery can be calculated by using the following formula;
that is, ASR (i) =Δu (i)/Δi;
the current-plane resistance curve is further smoothed using the following equation
ASR(i)＝α 1 ASR * (i-2Δi)+α 2 ASR * (i-Δi)+α 3 ASR * (i)+α 2 ASR * (i+Δi)+α 1 ASR * (i+2Δi)
Wherein the method comprises the steps of
2α 1 +2α 2 +α 3 ＝1
Wherein alpha is 1 ，α 2 ，α 3 Is a coefficient, and is set to 0.2 in this embodiment.
Step 4, respectively introducing quantitative air and fuel gas into an air inlet pipeline 14 and a fuel gas inlet pipeline 17 of the solid oxide fuel cell 13, firstly, obtaining sufficient fuel gas and air, namely, under the condition of no starvation phenomenon, and then, firstly, reducing the flow of the air for a proper amount for a plurality of times; and then returning the flow of the air to be sufficient, and reducing the flow of the fuel gas for a plurality of times. The I-V curve of the fuel cell system overall cell is measured by means of the electronic load 12.
As shown in FIG. 4, taking hydrogen as an example, the fuel gas is firstly fixed at a hydrogen flow rate of 2.0NL/min, and the air flow rates are sequentially set to be 3.0NL/min, 2.0NL/min, 1.5NL/min, 1.2NL/min, 1.0NL/min, 0.9NL/min, 0.8NL/min, 0.7NL/min and 0.65NL/min; as shown in FIG. 5, the air flow rate was fixed at 2.0NL/min, and the hydrogen flow rates were set to 1.0NL/min, 0.5NL/min, 0.4NL/min, 0.35NL/min, 0.32NL/min, 0.3NL/min, 0.28NL/min, 0.26NL/min, and 0.25NL/min, in that order.
And 5, determining a current-area resistance (I-ASR) curve when the air and the fuel gas are sufficient, as shown in fig. 4, observing that the upper resistance of the curve cannot rise in a high-current discharge state, setting the I-ASR curve at the moment as a standard curve, comparing the I-ASR curve under other conditions with the standard curve, observing that the upper resistance of the curve rises along with the increase of the current, generating a rising phenomenon, and the smaller the air supply flow is, the smaller the current of the upper resistance of the surface resistance is. The face resistance upturned is used as a criterion for the occurrence of fuel starvation, whether the fuel cell has the fuel starvation or not is diagnosed, and the obvious fuel starvation is started when the current under different air supply flows is determined.
As shown in fig. 4, the I-ASR curve of the cell in the case where the anode hydrogen supply amount was fixed and the cathode air supply amount was different, was a smooth curve when the hydrogen intake amount was 2.0NL/min and the air intake amount was 3.0NL/min, and the resistance of the cell gradually decreased with the increase of the current, and no abrupt increase in resistance occurred. Along with the reduction of the air inflow, the I-ASR curve starts to change gradually, when the current increases gradually, the curve starts to warp upwards to generate a resistance surge phenomenon, and the smaller the air inflow is, the more obvious the upward warp of the curve is, and the smaller the corresponding current is when the resistance surge is generated.
Therefore, it can be concluded that the solid oxide fuel cell has a sudden increase in resistance in the case of insufficient cathode air intake.
As shown in fig. 5, the I-ASR curve of the cell was obtained for different anode hydrogen intake amounts with the cathode air intake amount unchanged. The curve is a smooth curve without resistance surge in case of sufficient amounts of air and hydrogen. As the hydrogen gas inflow is reduced, the I-ASR curve starts to warp upwards, the phenomenon of sudden increase of resistance occurs in the battery, and the smaller the hydrogen gas inflow is, the smaller the current corresponding to the sudden increase of resistance is.
Therefore, it can be concluded that the solid oxide fuel cell has a sudden increase in resistance when the anode hydrogen intake amount is insufficient.
From the above experimental data, it can be seen that: the resistance of the fuel cell increases dramatically when starvation occurs, so based on this feature we can diagnose whether starvation occurs in the fuel cell by measuring and calculating the I-ASR curve of the fuel cell. Since the internal cell surface resistance is an intrinsic property of the cell, it is more feasible to set the surface resistance threshold against fuel starvation than the voltage threshold or the current threshold.
2. Split battery testing principle
Step 1, as shown in fig. 6, the cathode 16 of the solid oxide fuel cell 13 was measured to be divided into four regions: the first region 20, the second region 21, the third region 22 and the fourth region 23 are connected in parallel, and are placed in the high-temperature test furnace 1, so that a corresponding and proper high-temperature test environment is maintained, and the test structure is shown in fig. 7.
Step 2, connecting the four areas with local voltage leads 5 to the multi-channel voltmeter 11 to measure the corresponding local voltages, and knowing the measured four voltages V 'because the local voltage leads 5 have extremely small current and extremely small voltage division' 1 、V’ 2 、V’ 3 、V’ 4 For each partial cell voltage. The electronic load 12 is placed in the main circuit, and the current value I of the main circuit can be measured by the electronic load 12 Main unit And a voltage value V Main unit Obtaining the resistance R of each current lead 6 1 、R 2 、R 3 、R 4 The process is as follows:
the first 20, second 21, third 22 and fourth 23 batteries and the corresponding current leads 6 thereof are connected with the electronic load 12 and the corresponding ammeter voltmeter access circuit in sequence, and the resistance R of the corresponding current leads 6 is obtained by changing the resistance value of the electronic load 12 1 、R 2 、R 3 、R 4 . I.e.
Step 3, it can be seen that the battery current of the current lead 6 and the corresponding region is the same as I' 1 、I’ 2 、I’ 3 、I’ 4 The corresponding voltage of the current lead is the voltage V at the electronic load 12 Main unit And the cell voltage V 'of each region'The difference, i.e
Step 4, introducing quantitative air and fuel gas, namely firstly, the air and the fuel gas with the optimal quantity are the situation that starvation phenomenon does not exist, and then, firstly, the air flow rate is reduced for a plurality of times with the optimal quantity; and returning the air flow to an appropriate amount, and reducing the fuel gas flow for a plurality of times.
As shown in fig. 8 to 11, the air flow rate was fixed at 600Nml/min, the hydrogen flow rates were set at 100Nml/min,
60Nml/min，40Nml/min。
determining the I-V curve of each local area based on the experimental data and the calculation result and the I-V curve of the whole measured fuel cell, and calculating the more robust and more intrinsic I-ASR curve of each local area
And 5, firstly determining that the fuel gas and the air can be used as standard I-ASR curves when the air and the fuel gas are sufficient, then comparing the I-ASR curves in other cases with the standard I-ASR curves, and observing the sudden increase of the resistance on the curves so as to diagnose whether the fuel cell is partially starved or not and start obvious fuel starvation when the current is.
3. Cell stack testing principle
The cell stack is formed by connecting a plurality of fuel cell units in series, and if the fuel starvation of the cell stack is detected, the fuel starvation of different cell units is only detected directly. The method comprises the following specific steps:
step 1, as shown in fig. 12, the stack 24 is placed in a high temperature test furnace, the anode is supplied with hydrogen and the cathode is supplied with air, and the stack is operated.
And 2, taking the battery unit III 28, the battery unit V26 and the battery unit VI 25 as battery units to be detected, connecting the cathode and the anode of the battery stack 24 to the voltage test joint 8 and the current test joint 9 of the electronic load 12 in the normal temperature region through the voltage lead 7 and the current lead 6 respectively, and connecting the battery unit III 28, the battery unit V26 and the battery unit VI 25 with the multichannel voltmeter 11 through the local voltage lead 5 respectively.
Step 3, the voltage and the current of the cell stack 24 during operation can be obtained through the electronic load 12, and an I-V curve of the cell stack is drawn according to the current voltage values measured at each moment; voltages of a third battery 28, a fifth battery 26 and a sixth battery 25 can be measured through the multi-channel voltmeter 11.
And 4, measuring and calculating an I-ASR curve with more intrinsic characteristics of the battery according to the I-V curve of the battery stack obtained in the step 3, wherein the resistance is calculated by R=delta U/delta I. And observing whether the resistor is upwarp or not according to the obtained I-ASR curve, and if the resistor is upwarp, fuel starvation of the battery unit occurs.
As shown in fig. 13 to 15, I-ASR curves at different air concentrations were plotted for different three cells in the stack. As shown in fig. 13, cell three had a resistance that rose up at a current of 20A at an air concentration of 3.0NL/min and the cell was starved of fuel. As shown in fig. 14, cell five had a resistance of up at an air concentration of 3.0NL/min and a current of 18A, and the cell was starved of fuel. As shown in fig. 15, cell six had a resistance that rose up at a current of 25A at an air concentration of 3.0NL/min and the cell was starved of fuel.
As can be seen from fig. 13 to 15, the condition of whether or not fuel starvation occurs in different cells in the same stack may be different. The upwarp of the surface resistance can be used as a robust criterion of fuel starvation, and the fuel starvation condition of different battery units in the battery stack can be detected by a method for detecting the surface resistance of the fuel battery. The method has higher accuracy and sensitivity, and can be used for detecting the local fuel starvation of the fuel cell system, thereby making up the blank.
In the actual operation of a solid oxide fuel cell system, measuring the complete I-ASR curve still affects normal power supply; based on the above summary, the invention provides a fuel cell system fuel and air supply configuration method with strong practicability, which uses the upward warp of the surface resistance as a criterion for the occurrence of fuel starvation. If the surface resistance threshold value of the fuel cell is known, on the basis of the normal operation current I of the fuel cell system, a plurality of tiny current step sizes are appropriately increased and decreased, the voltage value under the corresponding current is measured, the surface resistance of the fuel cell under the current operation current I is calculated based on the current value and the voltage value, the surface resistance is compared with the surface resistance threshold value, if the measured value of the surface resistance is larger than the threshold value, the system is in a fuel starvation state, otherwise, the system fuel supply is sufficient; if the surface resistance threshold is unknown, the surface resistance of the battery close to a plurality of operation current values can be measured, the surface resistance is upwarp as a criterion for the occurrence of fuel starvation, if the surface resistance is upwarp along with the increase of the current, the system is in a fuel starvation state, otherwise, the system fuel supply is sufficient.
Claims (9)
1. A method for diagnosing fuel starvation and configuring air supply of an SOFC system, comprising the steps of:
placing the solid oxide fuel cell (13) into a high-temperature test furnace (1) at 650-900 ℃ to maintain a high-temperature test environment;
the cathode (16) of the solid oxide fuel cell (13) supplies air and the anode (19) supplies fuel gas;
measuring a current-voltage curve (I-V curve) of the solid oxide fuel cell (13) system as a whole using an electronic load (12) based on voltammetry;
measuring a local area voltage signal of the solid oxide fuel cell (13) using a multi-channel voltmeter (11);
determining a local area I-V curve based on the I-V curve of the whole solid oxide fuel cell (13) and the voltage signal of the local area measured by the multi-channel voltmeter (11);
calculating a current-area resistance (I-ASR) curve of the local area based on the I-V curve of the local area, wherein the area resistance is equivalent to the impedance of the fuel cell detected by an impedance spectroscopy at an ultralow frequency;
diagnosing whether the fuel starvation phenomenon exists in the part of the solid oxide fuel cell (13) according to the rising of the resistance on the obtained I-ASR curve;
the solid oxide fuel cell (13) is provided with a voltage local detection point (2), and the voltage local detection point (2) is connected with a voltage connector (10) of the multichannel voltmeter (11) through a local voltage lead (5); the cathode of the solid oxide fuel cell (13) is connected with a current test joint (9) of the electronic load (12) through a current lead (6); the anode of the solid oxide fuel cell (13) is connected to the voltage test connection (8) of the electronic load (12) via a voltage lead (7).
2. A method of diagnosing fuel starvation and supplying air in a SOFC system according to claim 1, wherein an air inlet pipe (14) is provided at the cathode (16) of the solid oxide fuel cell (13), the air inlet pipe (14) is located above the cathode (16), an air outlet pipe (15) is provided at one side of the cathode (16), and a current wire connector (3) is connected at the other side of the cathode (16); a fuel gas inlet pipeline (17) is arranged above an anode (19) of the solid oxide fuel cell (13), a fuel gas outlet pipeline (18) is arranged on one side of the anode (19), and a voltage line connector (4) is connected to the other side of the anode (19).
3. The method for diagnosing fuel starvation and supplying air of the SOFC system according to claim 2, wherein the air inlet pipe (14) and the fuel gas inlet pipe (17) of the solid oxide fuel cell (13) are respectively supplied with a certain amount of air and fuel gas, firstly sufficient air and fuel gas are used, that is, no starvation phenomenon exists, then the air flow is reduced a plurality of times in a proper amount, then the air flow is returned to a proper amount, and the fuel gas flow is reduced a plurality of times in a proper amount.
4. A method of SOFC system fuel starvation diagnosis and feed gas configuration according to claim 3, wherein the flow of air and fuel gas is controlled by a flow meter.
5. The method for diagnosing fuel starvation and configuring air supply of an SOFC system according to claim 3, wherein an I-ASR curve when air and fuel gas are sufficient is determined, the I-ASR curve is set as a standard curve, and resistance on the standard curve is observed not to rise in a high-current discharge state; then comparing the I-ASR curve of other conditions with a standard curve, and observing that the resistance on the curve rises suddenly along with the increase of the current to generate a rising phenomenon, wherein the smaller the air supply flow is, the smaller the current of rising of the surface resistance is; the face resistance upturned is used as a robust criterion for the occurrence of fuel starvation, diagnosing whether the fuel cell is suffering from fuel starvation, and determining what the current is at different air supply flows to begin to be obvious.
6. The SOFC system fuel starvation diagnosis and feed gas configuration method according to claim 1, wherein the solid oxide fuel cell comprises a monolithic cell, a split cell, a stack (24).
7. The method according to claim 6, wherein the dividing the solid oxide cell into a plurality of regions, and determining whether the divided cells are starved by detecting whether each region is starved.
8. The method of diagnosing fuel starvation and air supply configuration of a SOFC system of claim 6, wherein the stack (24) is formed by connecting several fuel cells in series, and determining whether the stack is starved by directly detecting whether different cells are starved.
9. The method for diagnosing fuel starvation and supplying air in a SOFC system according to claim 1, wherein in actual operation of the solid oxide fuel cell system, if the surface resistance threshold of the fuel cell is known, on the basis of the normal operation current of the fuel cell system, a plurality of minute current steps are appropriately increased or decreased, the voltage value at the corresponding current is measured, the surface resistance of the fuel cell at the current operation current is calculated based on the current value and the voltage value, and compared with the surface resistance threshold, if the measured value of the surface resistance is larger than the threshold, the system is in a fuel starvation state, otherwise, the system is sufficiently supplied; if the surface resistance threshold is unknown, the surface resistance of the battery close to a plurality of operation current values can be measured, the surface resistance is upwarp as a criterion for the occurrence of fuel starvation, if the surface resistance is upwarp along with the increase of the current, the system is in a fuel starvation state, otherwise, the system fuel supply is sufficient.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310110927.XA CN116314969B (en) | 2023-02-14 | 2023-02-14 | Fuel starvation diagnosis and air supply configuration method for SOFC system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310110927.XA CN116314969B (en) | 2023-02-14 | 2023-02-14 | Fuel starvation diagnosis and air supply configuration method for SOFC system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116314969A CN116314969A (en) | 2023-06-23 |
| CN116314969B true CN116314969B (en) | 2023-09-29 |
Family
ID=86789718
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310110927.XA Active CN116314969B (en) | 2023-02-14 | 2023-02-14 | Fuel starvation diagnosis and air supply configuration method for SOFC system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116314969B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102401883A (en) * | 2010-09-15 | 2012-04-04 | 通用汽车环球科技运作有限责任公司 | Method and signal processing algorithm to detect abnormal operation of individual fuel cell in plurality of series connected fuel cells |
| CN106374121A (en) * | 2015-07-21 | 2017-02-01 | 通用汽车环球科技运作有限责任公司 | Electrochemical hydrogen sensor for global/local hydrogen starvation detection in PEM fuel cells |
| CN112068019A (en) * | 2020-09-08 | 2020-12-11 | 清华大学 | Flat-plate SOFC current density distributed end plate test structure and test method |
| CN112582652A (en) * | 2020-12-08 | 2021-03-30 | 武汉理工大学 | Method for monitoring reverse pole degree of proton exchange membrane fuel cell |
| CN113764702A (en) * | 2021-09-08 | 2021-12-07 | 武汉理工氢电科技有限公司 | Method for evaluating anti-reverse polarity performance of fuel cell |
| CN114747058A (en) * | 2019-12-19 | 2022-07-12 | 宝马股份公司 | Method for diagnosing at least one fuel cell stack of a fuel cell device, computer-readable storage medium and fuel cell diagnostic system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6418245B2 (en) * | 2014-11-07 | 2018-11-07 | 日産自動車株式会社 | Fuel cell state determination device and method |
-
2023
- 2023-02-14 CN CN202310110927.XA patent/CN116314969B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102401883A (en) * | 2010-09-15 | 2012-04-04 | 通用汽车环球科技运作有限责任公司 | Method and signal processing algorithm to detect abnormal operation of individual fuel cell in plurality of series connected fuel cells |
| CN106374121A (en) * | 2015-07-21 | 2017-02-01 | 通用汽车环球科技运作有限责任公司 | Electrochemical hydrogen sensor for global/local hydrogen starvation detection in PEM fuel cells |
| CN114747058A (en) * | 2019-12-19 | 2022-07-12 | 宝马股份公司 | Method for diagnosing at least one fuel cell stack of a fuel cell device, computer-readable storage medium and fuel cell diagnostic system |
| CN112068019A (en) * | 2020-09-08 | 2020-12-11 | 清华大学 | Flat-plate SOFC current density distributed end plate test structure and test method |
| CN112582652A (en) * | 2020-12-08 | 2021-03-30 | 武汉理工大学 | Method for monitoring reverse pole degree of proton exchange membrane fuel cell |
| CN113764702A (en) * | 2021-09-08 | 2021-12-07 | 武汉理工氢电科技有限公司 | Method for evaluating anti-reverse polarity performance of fuel cell |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116314969A (en) | 2023-06-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11973248B2 (en) | Method for diagnosing degradation of fuel cell stack, method for multi-point analysis of fuel cell, and method for estimating performance of fuel cell membrane electrode | |
| US8470486B2 (en) | Fuel cell system | |
| CN100580988C (en) | Fuel cell system | |
| CN101669242B (en) | Fuel cell system | |
| US20120064424A1 (en) | Low cost method and signal processing algorithm to rapidly detect abnormal operation of an individual fuel cell in a plurality of series connected fuel cells | |
| JP5491787B2 (en) | Inspection method of fuel cell stack | |
| US10020525B2 (en) | Method and system for diagnosing state of fuel cell stack | |
| CN111224132B (en) | Shutdown purging method and system for fuel cell | |
| CN114094146A (en) | Method for testing hydrogen permeation current of fuel cell proton exchange membrane | |
| CN112582652B (en) | Method for monitoring reverse pole degree of proton exchange membrane fuel cell | |
| CN111525158A (en) | Method and device for detecting physical state of air-cooled hydrogen fuel cell | |
| US20050064252A1 (en) | Method for operating polymer electrolyte fuel cell | |
| US9080938B2 (en) | Extremum seeking algorithm in a variable time interval to detect anode pressure sensor stuck failure in a fuel cell system | |
| CN114583221B (en) | Method for measuring and calculating attenuation life of galvanic pile | |
| CN113611900A (en) | Membrane dry fault diagnosis method of proton exchange membrane fuel cell | |
| CN114628740B (en) | Method and device for detecting fluid distribution consistency of fuel cell stack | |
| WO2024152889A1 (en) | Method for analyzing water content in fuel cell | |
| CA2450848A1 (en) | Functional test and demonstration apparatus for fuel cell power system | |
| CN116314969B (en) | Fuel starvation diagnosis and air supply configuration method for SOFC system | |
| CN114709454B (en) | Fuel cell short-circuit resistance measurement method based on electrochemical impedance spectrum | |
| CN113346113B (en) | Method for calibrating optimal operation temperature of fuel cell system | |
| CN213903748U (en) | Anti-antipole test system of membrane electrode | |
| CN115064741A (en) | Method for calculating fuel cell fuel utilization rate based on internal resistance model | |
| CN113238151A (en) | Method for testing performance of fuel cell stack | |
| CN112611975A (en) | Anti-reversal testing system and anti-reversal testing method for membrane electrode |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |