Intelligent system for the dynamic modeling and operation of fuel cells
10122034 ยท 2018-11-06
Inventors
Cpc classification
H01M8/04305
ELECTRICITY
H01M8/04992
ELECTRICITY
Y02E60/50
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
H01M8/1065
ELECTRICITY
H01M8/1067
ELECTRICITY
International classification
H01M8/04
ELECTRICITY
H01M8/1067
ELECTRICITY
H01M8/04992
ELECTRICITY
H01M8/04298
ELECTRICITY
Abstract
A system and method for controlling an output of a dynamic fuel cell is provided. A dynamic fuel cell has a membrane wherein a dimension of the membrane is variable during operation of the dynamic fuel cell in response to a control signal from an intelligent controller. By varying the dimension of the membrane, the output voltage of the dynamic fuel cell can be altered. An intelligent controller is provided that can measure a number of outputs and input parameters of the dynamic fuel cell and approximate input parameters using the measured values to adjust the input of the dynamic fuel cell to the approximated values.
Claims
1. A method for controlling an output of a fuel cell having a membrane between an anode and a cathode and operative to vary at least one effective dimension of the membrane, said method comprising: continuously sense an output of the fuel cell; continuously approximate a given effective membrane dimension for a desired output of the fuel cell using a non-linear process model; and continuously control a membrane dimension control system associated with the fuel cell and operable to change an effective dimension of the membrane in order to selectively change said effective dimension of said membrane to said given effective membrane dimension.
2. A method for controlling an output of a fuel cell having a separation layer between an anode and a cathode and operative to vary at least one effective dimension of the separation layer, said method comprising: continuously sense an output of the fuel cell; continuously approximate a given effective separation layer dimension for a desired output of the fuel cell using a non-linear process model; and continuously control a separation layer dimension control system associated with the fuel cell and operable to change an effective dimension of the separation layer in order to selectively change said effective dimension of said separation layer to said given effective separation layer dimension.
3. The method of claim 2 wherein the separation layer comprises a plurality of layers.
4. The method of claim 2 wherein the at least one dimension is a thickness of the separation layer and wherein said separation layer dimension control system is operable to vary the thickness of the separation layer by at least one of: stretching and contracting the separation layer; applying pressure to outside surfaces of the cathode layer and the anode layer; introducing electronic pulses into the separation layer; bending at least one of the cathode layer and the anode layer to compress the separation layer; where the separation layer comprises a pair of outer layers and an inner layer positioned in between the pair of outer layers, the inner layer containing a liquid film, selectively supplying and evacuating liquid from the inner layer.
5. The method of claim 2 wherein the at least one dimension is a thickness of the separation layer and wherein the thickness of the separation layer is varied by at least one of: stretching and contracting the separation layer; applying pressure to outside surfaces of the cathode layer and the anode layer; introducing electronic pulses into the separation layer; bending at least one of the cathode layer and the anode layer to compress the separation layer; where the separation layer comprises a pair of outer layers and an inner layer positioned in between the pair of outer layers, the inner layer containing a liquid film, selectively supplying and evacuating liquid from the inner layer.
6. The method of claim 1 wherein the at least one dimension is a contact area between the membrane and the anode layer and the membrane and the cathode layer and wherein said membrane dimension control system is operable to vary the contact area by at least one of: moving at least one of the cathode layer and the anode layer relative to the membrane; moving the membrane relative to at least one of the cathode layer and the anode layer; bending at least one of the cathode layer and the anode layer, relative to the membrane; moving at least one of the cathode layer and anode layer longitudinally in relation to the membrane.
7. The method of claim 1 wherein the at least one dimension is a contact area between the membrane and the anode layer and the membrane and the cathode layer and wherein the contact area is varied by at least one of: moving at least one of the cathode layer and the anode layer relative to the membrane; moving the membrane relative to at least one of the cathode layer and the anode layer; bending at least one of the cathode layer and the anode layer, relative to the membrane; moving at least one of the cathode layer and anode layer longitudinally in relation to the membrane.
8. The method of claim 1 wherein the at least one dimension is at least one of a thickness of the membrane and a contact area between at least one of the anode layer and the membrane and the cathode layer and the membrane, and said membrane dimension control system is operable to rotate at least one of the cathode layer, the anode layer and the membrane to vary at least one of said thickness and said contact area.
9. The method of claim 1 wherein the at least one dimension is at least one of a thickness of the membrane and a contact area between at least one of the anode layer and the membrane and the cathode layer and the membrane, and comprising rotating at least one of the cathode layer, the anode layer and the membrane to vary at least one of said thickness and said contact area.
10. A method for controlling an output of a fuel cell having a membrane between an anode and a cathode and operative to vary at least one effective dimension of the membrane, said method comprising: continuously sense an output of the fuel cell; continuously approximate a given effective membrane dimension for a desired output of the fuel cell using a non-linear process model; and continuously change an effective dimension of the membrane in order to selectively change said effective dimension of said membrane to said given effective membrane dimension.
11. The method of claim 10 wherein the at least one dimension of the membrane is at least one of: a thickness of the membrane and a contact surface between an anode layer and a cathode layer.
12. The method of claim 10 wherein the at least one dimension is a thickness of the membrane and wherein the thickness of the membrane is varied by at least one of: stretching and contracting the membrane; applying pressure to outside surfaces of the cathode layer and the anode layer; introducing electronic pulses into the membrane; bending at least one of the cathode layer and the anode layer to compress the membrane; where the membrane comprises a pair of outer membrane layers and an inner layer positioned in between the pair of outer membrane layers, the inner layer containing a liquid film, selectively supplying and evacuating liquid from the inner layer.
13. The method of claim 10 wherein the at least one dimension is a contact area between the membrane and the anode layer and the membrane and the cathode layer and wherein the contact area is varied by at least one of: moving at least one of the cathode layer and the anode layer, relative to the membrane; moving the membrane relative to at least one of the cathode layer and the anode layer; bending at least one of the cathode layer and the anode layer, relative to the membrane; moving at least one of the cathode layer and anode layer longitudinally in relation to the membrane.
14. The method of claim 10 wherein the at least one dimension is at least one of a thickness of the membrane and a contact area between at least one of the anode layer and the membrane and the cathode layer and the membrane, and comprising rotating at least one of: the cathode layer and the anode layer relative to the membrane to vary at least one of said thickness and said contact area.
15. The method of claim 2 wherein the at least one dimension of the separation layer is at least one of: a thickness of the separation layer and a contact surface between an anode layer and a cathode layer.
16. A method for controlling an output of a fuel cell having a separation layer between an anode and a cathode and operative to vary at least one effective dimension of the separation layer, said method comprising: continuously sense an output of the fuel cell; continuously approximate a given effective separation layer dimension for a desired output of the fuel cell using a non-linear process model; and continuously change an effective dimension of the separation layer in order to selectively change said effective dimension of said separation layer to said given effective separation layer dimension.
17. The method of claim 16 wherein the at least one dimension of the separation layer is at least one of: a thickness of the separation layer and a contact surface between an anode layer and a cathode layer.
18. The method of claim 16 wherein the at least one dimension is a thickness of the separation layer and wherein the thickness of the separation layer is varied by at least one of: stretching and contracting the separation layer; applying pressure to outside surfaces of the cathode layer and the anode layer; introducing electronic pulses into the separation layer; bending at least one of the cathode layer and the anode layer to compress the separation layer; where the separation layer comprises a pair of outer separation layer layers and an inner layer positioned in between the pair of outer separation layer, the inner layer containing a liquid film, selectively supplying and evacuating liquid from the inner layer.
19. The method of claim 1 wherein said continuously approximate further comprises continuously approximating each of an amount of fuel, an amount of oxygen, and a temperature for said desired output of the fuel cell using said non-linear process model, and wherein said continuously change further comprises, based on approximations from said continuously approximate, continuously changing said amount of fuel, said amount of oxygen, and said temperature along with continuously changing said effective dimension of the membrane.
20. The method of claim 19 wherein said continuously change further comprises simultaneously changing said amount of fuel, said amount of oxygen, said temperature, and said effective dimension of the membrane.
21. The method of claim 16 wherein said continuously approximate further comprises continuously approximating each of an amount of fuel, an amount of oxygen, and a temperature for said desired output of the fuel cell using said non-linear process model, and wherein said continuously change further comprises, based on approximations from said continuously approximate, continuously changing said amount of fuel, said amount of oxygen, and said temperature along with continuously changing said effective dimension of the membrane.
22. The method of claim 21 wherein said continuously change further comprises simultaneously changing said amount of fuel, said amount of oxygen, said temperature, and said effective dimension of the membrane.
Description
DESCRIPTION OF THE DRAWINGS
(1) While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like pasts in each of the several diagrams axe labeled with like numbers, and where:
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DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
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(17) The dynamic fuel cell 110 uses a fuel, such as hydrogen, methanol or any other fuel suitable to be used in a fuel cell, to generate an output voltage, V.sub.cell, and output current, I.sub.cell, which is supplied to a load 180). In a general aspect, the dynamic fuel cell 110 can be square, rectangular, circular, cylindrical, ball or tube type and of variable configuration. The anode, cathode and or membrane dimension parameters may be appropriately varied according to a proper operation control scheme. The dynamic fuel cell 110 is operative to vary at least one dimension of a membrane in the dynamic fuel cell 110 in response to a control signal from the intelligent controller 120.
(18) Fuel cell control system 100 has a number of systems that provide input to the dynamic fuel cell 110. These systems include: a fuel input system 130; a temperature control system 140; a membrane dimension control system 150; and on oxygen supply system 160.
(19) The fuel input system 130 provides the fuel to the dynamic fuel cell 110. For example, for a hydrogen fuel cell, the fuel input system 130 supplies the needed hydrogen to the dynamic fuel cell 110, although the fuel input system 130 could also be used to supply any type of fuel that can used in the dynamic fuel cell 110. The fuel inputs system 130 has a number of controllable variables in its supply of fuel to the dynamic fuel cell 110. These variables include the concentration of the incoming fuel, the pressure of the incoming fuel and/or the velocity of the incoming fuel.
(20) The temperature control system 140 is operative to vary the operating temperature of the dynamic fuel cell 110. In one aspect it could be a pressurized coolant system that can vary the flow of coolant through the dynamic fuel cell 110 in other aspects it could comprises a fan portion and/or vary the temperatures of the incoming fuel and oxygen.
(21) The membrane dimension control system 150, in one aspect, is operative to vary the thickness of a membrane in the dynamic fuel cell 110 and, in another aspect, is operative to vary the contact area between the membrane and the incoming fuel and oxygen. These dimensions can be varied by a number of mechanical, electronic, electromagnetic, electrostatic, electro-mechanical, electro-mechanical-chemical, chemical or other mechanisms.
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(23) In one aspect, the thickness, T, of the membrane 210 can be varied by stretching and contracting the membrane 210. By applying a force to the membrane 210, such as a mechanical force, along the X-axis, Y-axis, Z-axis or combination of two or more, the thickness, T, of membrane 210 can be varied. Alternatively, the anode layer 270 and cathode layer 230 could be rotated slightly, for example, in a screw like manner, in relation to each other causing the thickness, T, of the membrane 210 to be varied.
(24) Additionally, the thickness, T, of the membrane 210 can be varied by exerting pressure to the outer surfaces of both the anode layer 220 and cathode layer 230 in directions A and B. By increasing the pressure exerted on the outer surfaces of the anode layer 220 and cathode layer 230, the thickness, T, of the membrane 210 can be decreased and vice versa.
(25) The anode layer 220 and cathode layer 210 can also be bent to produce pressure on the membrane 210 which will result in the thickness, T, of the membrane 210 being varied.
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(28) Additionally, the concentration of the protons in the liquid solution will also change, changing the performance of the dynamic fuel cell 110, rapidly.
(29) Referring again to
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(32) Referring again to
(33) All of these controllable variables in the fuel supply system 130, temperature control system 140, membrane dimension control system ISO and oxygen supply system 160 have a significant effect on performance of the dynamic fuel cell 110. These variables are related to the voltage output, V.sub.cell, and current output, I.sub.cell, of the dynamic fuel cell 110 by a complicated and highly non-linear function. By altering the variables, the performance of the dynamic fuel cell 110 can be greatly varied.
(34) The intelligent controller 120 is operative to control the operation of the fuel supply system 130, temperature control system 140, membrane dimension control system 150 and the oxygen supply system 160, respectively. The intelligent controller 120 monitors the voltage output, V.sub.cell, and the current output, I.sub.cell, of the dynamic fuel cell 110 and uses these measured values to alter the variables in the fuel supply system 130, temperature control system 140, membrane dimension control system 150 and the oxygen supply system 160. In order to control the output of the dynamic fuel cell 110 using a relatively large number of input parameters of the dynamic fuel cell 110 in real-time, the intelligent controller 120 uses a nonlinear process model such as an artificial neural network, fuzzy inference system, neuro-fuzzy inference system and or other advance inference system to quickly approximate the needed input parameters based on a demanded or desired output voltage for the dynamic fuel cell 110. The intelligent controller 120 then uses the approximated input parameters to control the variables in the fuel supply system 130, temperature control system 140, membrane dimension control system 150 and the oxygen supply system 160 to result in the dynamic fuel cell 110 providing the desired voltage output.
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(36) At step 710 of the method 700, the intelligent controller 120 measures the voltage output and current output of the dynamic fuel cell 110 and these measured values are then used to determine a demanded voltage at step 720 that is demanded by the load 180.
(37) At step 730 the method 700 uses the calculated demanded voltage and the nonlinear process model to approximate desired input parameters for the dynamic fuel cell 110.
(38) At step 740 the intelligent controller 120 controls the dynamic fuel cell 110 by adjusting the various input parameters to match approximated input parameters determined at step 730. The intelligent controller 120 provides signals to the fuel input system 130; the temperature control system 140; the membrane dimension control system 150; and the oxygen supply system 160 which set these systems to provide the input parameters approximated by the intelligent controller 120. Operating under the adjusted input parameters, the dynamic fuel call 110 will provide a voltage output the same as or sufficiently close to the voltage demanded by the load 180.
(39) In this manner, die intelligent controller 120 allows real-time control of the voltage output of the dynamic fuel cell 110. As the voltage demanded or desired by the load 180 varies, the intelligent controller 120 approximates new input parameters that will produce the demanded or desired voltage (or sufficiently close voltage) and adjusts the inputs to the dynamic fuel cell 110, accordingly. By adjusting the above mentioned input parameters, a wide range of voltage outputs can be achieved with the dynamic fuel cell 110.
(40) The intelligent controller 120 can be tuned and optimized by obtaining experimental data from an actual dynamic fuel cell 110. Outputs of the dynamic fuel cell 110 and their corresponding inputs can be recorded and used to train or tune the artificial neural network, fuzzy inference system, neuro-fuzzy inference system and/or other advanced inference system methodologies used by the intelligent controller 120. Alternatively, outputs of the dynamic fuel cell 110 and their corresponding inputs can be determined by solving mathematical functions describing the operation of the dynamic fuel cell 110 and these determined values used to tune and/or optimize the intelligent controller 120 directly. Although the complicated and highly nonlinear equations describing the operation of the intelligent controller 120 may not be solvable in real-time while the dynamic fuel cell 110 is in operation, it is often possible to solve them for various inputs and outputs given enough time. A data set to configure the intelligent controller 120 can be determined by solving for the equations to create a sufficient data set for training.
(41) In a further aspect, the dynamic fuel cell 110 can be modeled using an intelligent model that models nonlinear processes in order to emulate the operation of the dynamic fuel cell 110. For many engineering and science problems, in order to analyze or to optimize some processes, sometimes it is not possible nor necessary to perform costly laboratory experiments using the dynamic fuel cell 110 to get meaningful data over a wide spectrum of operation conditions, in order to configure the intelligent controller 120 to approximate input parameters that will result in a output voltage, Vcell, of the dynamic fuel cell 110 that is sufficiently close to the desired or demanded voltage. The intelligent model that is created is then used to determine a set of outputs and their corresponding set of inputs in order to train the intelligent controller 120.
(42) The method 800 begins at step 810, where a first data set is determined comprising the values of a set of input parameters and the output resulting from die set of input parameters for the dynamic fuel cell 110. Typically, the output cell voltage is determined for a corresponding set of input parameters which comprise fuel variables, temperature, membrane dimensions, cell current and oxygen variables (the same input parameters that can be adjusted by the intelligent controller 120). The first data set doe not have to be extensive with each set of possible input parameters and the resulting output for the entire operating range of the dynamic fuel cell 110, but rather just a subset of the range of operation of the dynamic fuel cell 110, with enough data to create a sufficient model of the dynamic fuel cell 110.
(43) The first data set can be determined or obtained in a number of ways. The output resulting from a set of input parameters can be determined by calculating from the highly non-linear function equations and/or obtained from other trained intelligent systems and/or from experimentation.
(44) The highly non-linear function equations can be solved, for various sets of input variables, to determine a calculated output of the dynamic fuel cell 110. In some cases it is possible to solve the equations describing the operation of the dynamic fuel cell 110. While these equations are complicated and highly nonlinear making it hard to calculate solutions, they are not necessarily unsolvable. However, while they may be solvable, the time and effort needed to solve them for various input variables can be quite extensive; making it impractical to use the equations in the intelligent controller 120 where input parameters must be determined in real time conditions. However, even with the time and effort required to solve the equations describing the operation of the dynamic fuel cell 110, because the creation of the first data set does not require it to be done tinder a real-time constraint, like the operation of the intelligent controller 120.
(45) Experimentation on the dynamic fuel cell 110 can also be done to create the corresponding output values to input parameters values of the first data set. By varying the input parameter of the dynamic fuel cell 110 and recording the resulting output of the dynamic fuel cell 110 the first data set can be determined.
(46) Alternatively, nonlinear process models can also be used to generate some initial data which can be used to determine the output values and corresponding input values for the first data set.
(47) Referring again to
(48) The intelligent model 1000 is a nonlinear process model and can be implemented using an artificial neural network, a fuzzy inference system, a neuro-fuzzy inference system (for example, although not necessarily, of the CANFIS type), and/or any other advanced inference system.
(49) Referring again to
(50) Once the intelligent model 1000 has been sufficiently configured by training it or properly parameter updating/tuning it, the intelligent model 1000 will closely approximate the voltage output, V.sub.cell, for the dynamic fuel cell 110 for a given set of input parameters. Providing the values for the input parameters of the fuel variables 1030, the temperature 1040, the membrane dimensions 1050, the cell current 1055 and the oxygen variables 1060 to the intelligent model 1000, causes the intelligent model 1000 to approximate a voltage output 1070, which will be sufficiently close to or the same as the output of the dynamic fuel cell 110 for the provided input parameters. By changing any or all of the input parameters of the intelligent model 1000, an approximation of the cell voltage 1070 is provided by the intelligent model 1000.
(51) At step 840, the intelligent model 1000 is used to determine a second data set of input parameter values and the corresponding approximated output in order to configure the intelligent controller 120 by training or tuning using the second data set. The second data set is created of a subset of inputs to the fuel cell model 1000 and the resulting cell voltage 1070 that is sufficient to train or update the intelligent controller 120.
(52) At step 850, the intelligent controller 120 is configured by training and/or updating the intelligent controller 120 using the second data set generated at step 840 of the method 800.
(53) Using method 800, the intelligent controller 120 is configured to provide approximations of the input parameters so that by adjusting the input parameters of the dynamic fuel cell 110 to the approximated input parameters, the output voltage, V.sub.cell, will be sufficiently close to the voltage demanded or desired by the load 180.
(54) Experimental data from the dynamic fuel cell 110, input and outputs calculated for the dynamic fuel cell 110 or the method 800 can also be used to configure a variety of intelligent controllers that can be used to adjust one or more of a number of different input parameters. An intelligent controller can be configured, to measure the voltage output, V.sub.cell, the current output, I.sub.cell, of the dynamic fuel cell 110 and any of the variable input parameters to the dynamic fuel cell 110 to approximate a value for any of the variable input parameters that the intelligent controller can adjust so that the dynamic fuel cell 110 has a voltage output, V.sub.cell, the same or close to a voltage demanded or desired by a load 180. For example,
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(60) The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the exact constriction and operation shown and described, and accordingly, all such suitable changes or modifications in structure or operation which may be resorted to are intended to fall within the scope of the claimed invention.