Fuel cell system with dynamic power distribution

Abstract

A method and system for distribution of a plurality of fuel cell systems (FCSs) configured to provide electrical energy. The distribution is configured to determine a demand for electrical energy by a load and to implement a power supply operation accordingly. The power supply operation performs a start-up operation according to a start-up order specified for one or more auxiliary FCSs of the FCSs. The power supply operation includes individually implementing the start-up operation for each of the auxiliary FCSs according to the start-up order, and while each of the auxiliary FCSs is implementing the start-up operation, controlling another one or more of the FCSs to mask power variations associated therewith.

Description

Technical Field

[0001] This disclosure generally relates to power distribution, such as, but not limited to, the distribution of types of electrical energy that can be obtained from multiple independently operating fuel cell systems (FCS) in a dynamic and coordinated manner. Background Technology

[0002] Fuel cells convert fuel into usable electricity through a chemical reaction. A significant advantage of this energy-generating device is that it is achieved without relying on combustion as an intermediate step. Consequently, fuel cells offer several environmental advantages over internal combustion engines (ICEs) and related power sources used for propulsion and related power applications. In typical fuel cells, such as proton exchange membrane or polymer electrolyte membrane fuel cells, a pair of catalytic electrodes are separated by an ion transport medium commonly known as a membrane electrode assembly (MEA).

[0003] An electrochemical reaction occurs when a first reactant, in the form of a gaseous reducing agent (such as hydrogen, H2), is introduced to the anode and ionized there, and then passed through an ion transport medium to combine with a second reactant, in the form of a gaseous oxidizing agent (such as oxygen, O2), which has already been introduced through the other electrode (cathode); this reactant combination forms water as a byproduct. Electrons released during the ionization of the first reactant enter the cathode as direct current (DC) via an external circuit, which typically includes a load (such as an electric motor, device, etc.) in which useful work can be performed. The power generated by this DC current can be increased by combining many such cells into a larger current-generating assembly. In one such configuration, fuel cells are connected along a common stack dimension (much like a deck of cards) to form a fuel cell stack.

[0004] A fuel cell stack, along with its associated compressors, supplies, valves, sensors, controllers, etc., is defined as an integral or collectively independent entity when considered as a whole. An FCS can be characterized accordingly as an integrated system or a separate functional element or structure having all or most of the components required to operate one or more fuel cell stacks; optionally, associated resources are included within a common housing or encapsulation. FCSs possess significant energy storage density, and therefore, devices such as automobiles, vehicles, equipment, etc., that rely on them have historically depended on a single instance of an FCS—that is, a single FCS providing its power requirements. However, like other electrical energy sources, FCSs can be connected in series or parallel, such as in the form of power plants, to provide a greater amount of power.

[0005] The scalability of connecting multiple FCSs in a power plant (especially when doing so to achieve higher power levels, such as megawatts) can be problematic due to the variability inherent in the manufacturing of individual FCSs. Manufacturing tolerances (such as those associated with capacity, throughput, efficiency, etc.) can vary on an FCS-by-FCS basis, amplifying the differences between FCSs as the size of the power plant increases. Therefore, the problem becomes more pronounced and complex with each additional FCS. Some differences present at the initial construction and implementation (i.e., at manufacturing or initial deployment) can often be mitigated by technicians or other skilled individuals through testing, reconfiguration, or other ad hoc corrections performed during construction or prior to deployment. While this early capability mitigates some differences between FCSs, this intervention aims to correct for current or pre-existing setups, unlike unknowns that develop over time due to degradation and tolerance creep.

[0006] As equipment progresses through its life cycle, the changes present at deployment become inherently more variable and dramatic, and in some cases, may introduce entirely new variations. For example, a high-power implementation may be designed to be a robust, long-term operating solution intended to operate over a significant life cycle and under numerous operating and environmental conditions. Longer life cycles and unknown environments are difficult to predict, and therefore, it is difficult to adequately compensate for the use of pre-manufacturing or pre-deployment corrections. Variableness and foreseeable challenges and obstacles are, to some extent, intangible and speculative. These uncertainties become even more pronounced when the life cycle necessitates replacement or repair of the FCS and / or its components due to normal wear and tear. Replacement and repair may result in the addition of fuel cells or other components, possibly from other suppliers or under new or unknown conditions. When implementing newer / repaired FCS components, any changes or manipulations made at the time of manufacturing or prior to repair or replacement become essentially inapplicable. Summary of the Invention

[0007] This document discloses methods and systems for dynamically distributing electrical energy from a fuel cell system (FCS) to one or more loads, such as for supplying power to equipment, vehicles, motors, heavy equipment, stationary power plants, or other electrically operable devices through the coordinated activities of multiple FCSs capable of scalable high-power or megawatt operation. Distribution can be controlled according to power supply operations, whereby the FCSs are dynamically ranked and coordinated according to their power capabilities, and in some cases sequentially, adapting to time-varying FCS operating characteristics based on start-up and shutdown operations. For example, ranking can be used to periodically or continuously update the start-up order and / or shutdown to account for FCS performance variations, while simultaneously adjusting the distribution to meet demand fluctuations. Start-up operations can include masking operations to conceal start-up changes, and shutdown operations can similarly include hiding operations to conceal shutdown changes. Masking and concealment operations with collaborative and dynamic ranking can help coordinate the power distribution of FCSs in a flexible manner and adjust operations according to fluctuations and other changes associated with the equipment used, such as taking into account differences between FCSs due to use, degradation, degradation, tolerance creep, wear and damage, replacement, maintenance and other types of effects that are difficult to predict or foresee.

[0008] One aspect of this disclosure relates to a dynamic power distribution method for a vehicle having multiple fuel cell systems (FCS). The method includes determining the power capability of each FCS individually to supply electrical energy to a traction motor and determining a power request representing the traction motor's demand for electrical energy. The method then contemplates implementing a power supply operation to meet the demand. The power supply operation includes performing a startup operation according to a specified startup order for one or more auxiliary FCSs among the FCSs, the startup order listing the auxiliary FCSs sequentially relative to the primary FCS. By implementing the power supply operation individually for each of the auxiliary FCSs according to the startup order, each of the auxiliary FCSs begins its startup operation before the primary FCS and thus completes its startup operation accordingly.

[0009] Methods could include controlling the FCS to perform a masking operation to mask the startup changes of the next FCS that occurs after it in the startup sequence (such as by determining the startup change to be equal to the startup electrical energy provided when the FCS undergoes a startup operation alone), and correspondingly controlling the next FCS to mask the startup change by providing supplemental electrical energy equal to the startup amount.

[0010] Once startup is complete, the approach can be to control the FCS to operate in load-following mode, where each FCS provides a target power in order of total power associated with demand. The target power equals the corresponding supplementary amount plus a proportional amount, which is, for example, a percentage determined based on the upper limit of the corresponding FCS and the total power requested in the demand. The upper limit can be determined as a value specified within the power capacity defined for the corresponding FCS.

[0011] Once the load-following mode is complete or it is determined that one or more of the FCSs need to be shut down in another way, a method can be conceived to control the last FCS to perform a shutdown operation, causing the last FCS listed in the startup sequence to stop providing its associated target power. Shutdown can further include controlling the preceding FCS in the startup sequence to perform a hiding operation to conceal the shutdown change that occurs when the last FCS performs the shutdown operation. For example, the shutdown change could be equal to the shutdown energy provided by the last FCS during the shutdown process. The preceding FCS can conceal the shutdown change by providing complementary energy equal to the shutdown amount, and thereafter, once the last FCS completes its shutdown operation, the preceding FCS can be controlled to stop providing complementary energy.

[0012] One approach is to determine the startup order in alignment with a ranking of FCS types based on the sum of ranking values ​​calculated for each of several characteristics, such as the sum of the ranking values ​​calculated for each of the multiple characteristics, in order of power capability. For example, the multiple characteristics are values ​​that can be associated with or otherwise weighted with active fault characteristics, available or usable power characteristics, efficiency characteristics, and thermal capacity characteristics to generate a normalized ranking.

[0013] One aspect of this disclosure relates to a dynamic power distribution system. The system may include multiple fuel cell systems (FCS) configured to provide electrical energy and a controller configured to selectively distribute electrical energy from one or more of the FCSs to a load. The controller may include a processor and a memory having a plurality of non-transitory instructions, which, when executed by the processor, are configured to determine the load's demand for electrical energy and to perform power supply operations to meet that demand. Power supply operations may include performing startup operations according to a startup sequence specified for one or more auxiliary FCSs in the FCS. Power supply operations may include performing startup operations individually for each of the auxiliary FCSs according to the startup sequence, and controlling another or more of the FCSs to mask associated power changes while each of the auxiliary FCSs is performing a startup operation.

[0014] The FCS can be controlled to mask startup changes by providing supplemental electrical energy in proportion to the startup changes.

[0015] After the startup operation is completed, the FCS can be controlled to provide a target power equal to the corresponding supplementary amount plus a percentage of the total power requested in the demand.

[0016] The last FCS can be controlled to perform a shutdown operation in accordance with the control of the last FCS to stop providing the target power, and in conjunction with this, the preceding FCS can optionally be controlled to perform a hiding operation to hide the shutdown change that occurs when the last FCS performs a shutdown operation. The hiding operation may include the preceding FCS providing complementary electrical energy close to the shutdown change.

[0017] The system may include a vehicle with a traction motor and multiple FCSs, wherein the traction motor requires at least a portion of the load.

[0018] The system may include the ability to provide at least 1 megawatt of power, such as when the outputs of multiple FCSs are combined.

[0019] One aspect of this disclosure relates to a method for controlling the distribution of multiple fuel cell systems (FCS) configured to provide megawatt-level electrical energy. The method includes determining the load's demand for electrical energy and implementing power supply operations to meet that demand. The power supply operations may include performing startup operations according to a specified startup sequence for one or more auxiliary FCSs among the FCSs. The power supply operations may include individually implementing a startup operation for each of the auxiliary FCSs according to the startup sequence, and controlling one or more of the other FCSs to mask associated power changes while each of the auxiliary FCSs is performing a startup operation.

[0020] The above features and advantages, as well as other features and incidental advantages of this disclosure, will readily become apparent from the following detailed embodiments, taken in conjunction with the accompanying drawings and claims, and from the illustrative examples and models used to carry out this disclosure. Furthermore, this disclosure explicitly includes combinations and sub-combinations of the elements and features presented above and below.

[0021] The present invention also includes the following technical solutions.

[0022] Technical Solution 1. A dynamic power distribution method for a vehicle having multiple fuel cell systems (FCS), the method comprising:

[0023] Determine the power capacity of each FCS to individually supply electrical energy to the traction motor, which converts electrical energy into mechanical energy to propel the vehicle.

[0024] Determine the power request of the traction motor, which represents the traction motor's demand for electrical energy; and

[0025] Power supply operation is implemented to meet the demand. The power supply operation includes performing a startup operation according to a startup order specified for one or more auxiliary FCSs in the FCS. The startup order lists the auxiliary FCSs in order relative to the main FCS in the FCS. The power supply operation includes performing a startup operation individually for each of the auxiliary FCSs according to the startup order, such that each of the auxiliary FCSs begins its startup operation after the main FCS, and each auxiliary FCS thus completes its startup operation.

[0026] Technical Solution 2. The method according to Technical Solution 1 further includes controlling the FCS to perform a masking operation to mask the startup changes of the next FCS that occurs subsequently in the startup sequence.

[0027] Technical Solution 3. The method according to Technical Solution 2, wherein the startup change is equal to the startup electrical energy provided when the FCS undergoes a startup operation alone.

[0028] Technical Solution 4. The method according to Technical Solution 3 further includes controlling the next FCS to mask startup changes by providing supplemental electrical energy equal to the startup amount.

[0029] Technical Solution 5. The method according to Technical Solution 4 further includes controlling the FCS to operate according to a load follow mode after the startup operation is completed, the load follow mode corresponding to a target power provided by each FCS, the target power being equal to the corresponding supplementary amount plus a proportional amount, the proportional amount being a percentage determined based on the upper limit of the corresponding FCS and the total power requested in demand.

[0030] Technical Solution 6. The method according to Technical Solution 5 further includes determining the upper limit as equal to a value specified within the power capability determined for the corresponding FCS.

[0031] Technical Solution 7. The method according to Technical Solution 5 further includes, after completing the startup operation for each of the FCS:

[0032] Controlling the last FCS to perform a shutdown operation, the last FCS listed last in the startup sequence, the shutdown operation corresponds to controlling the last FCS to stop providing the target power; and

[0033] In the control startup sequence, the preceding FCS performs a hiding operation to hide the shutdown change that occurs when the last FCS performs a shutdown operation, the shutdown change being equal to the shutdown electrical energy provided by the last FCS during the shutdown operation.

[0034] Technical Solution 8. The method according to Technical Solution 7 further includes controlling the preceding FCS to hide the shutdown change by providing complementary electrical energy equal to the shutdown amount.

[0035] Technical Solution 9. The method according to Technical Solution 8 further includes controlling the previous FCS to stop providing complementary electrical energy after the last FCS completes the shutdown operation.

[0036] Technical Solution 10. The method according to Technical Solution 1 further includes determining the startup order to be aligned with the ranking, wherein the ranking ranks the FCSs in order based on the power capabilities determined for the FCS.

[0037] Technical Solution 11. The method according to Technical Solution 10, further comprising determining a ranking based on the sum of ranking values ​​calculated for each of a plurality of characteristics determined for the corresponding FCS.

[0038] Technical Solution 12. The method according to Technical Solution 11, wherein the plurality of characteristics includes active fault characteristics, available or usable power characteristics, efficiency characteristics, and thermal capacity characteristics.

[0039] Technical Solution 13. A dynamic power distribution system, comprising:

[0040] Multiple fuel cell systems (FCS) configured to provide electrical energy; and

[0041] A controller configured to selectively distribute electrical energy from one or more of the FCSs to a load, the controller including a processor and a memory, the memory including a plurality of non-transitory instructions, which, when executed by the processor, are configured to:

[0042] Determine the load's power requirements; and

[0043] To enable power supply operations to meet demand, the power supply operations include performing startup operations according to a startup sequence specified for one or more auxiliary FCSs in the FCS, the startup sequence being a sequential list of auxiliary FCSs relative to the primary FCS in the FCS, the power supply operations include individually performing a startup operation for each of the auxiliary FCSs according to the startup sequence, and controlling another or more of the FCSs to mask the associated startup changes while each of the auxiliary FCSs is performing a startup operation.

[0044] Technical Solution 14. The system according to Technical Solution 13, wherein the instructions are configured to control the FCS to mask the startup change by providing supplemental electrical energy proportional to the startup change.

[0045] Technical Solution 15. The system according to Technical Solution 14, wherein the instructions are configured to control the FCS to provide a target power after the startup operation is completed, the target power being equal to the corresponding supplementary amount plus a percentage of the total power requested in the demand.

[0046] Technical Solution 16. The system according to Technical Solution 15, wherein the instructions are configured to:

[0047] Controlling the last FCS to perform a shutdown operation, the last FCS listed last in the startup sequence, the shutdown operation corresponds to controlling the last FCS to stop providing the target power; and

[0048] In the control startup sequence, the preceding FCS performs a hiding operation to conceal the shutdown change that occurs when the last FCS performs a shutdown operation. The hiding operation includes the preceding FCS providing complementary electrical energy close to the shutdown change.

[0049] Technical Solution 17. The system according to Technical Solution 16, wherein the instructions are configured to control the previous FCS to stop providing complementary electrical energy once the last FCS has completed its shutdown operation.

[0050] Technical Solution 18. The system according to Technical Solution 13 further includes a vehicle having a traction motor and a plurality of FCSs, wherein the traction motor requires at least a portion of the load.

[0051] Technical Solution 19. The system according to Technical Solution 13, wherein a plurality of FCSs are configured to provide at least 1 megawatt of power when combined.

[0052] Technical Solution 20. A method for controlling the allocation of multiple fuel cell systems (FCS) configured to provide megawatt-level electrical energy, the method comprising:

[0053] Determine the load's power requirements; and

[0054] To enable power supply operations to meet demand, the power supply operations include performing startup operations according to a startup sequence specified for one or more auxiliary FCSs in the FCS, the startup sequence of which lists the auxiliary FCSs sequentially relative to the primary FCS in the FCS, the power supply operations include performing a startup operation individually for each of the auxiliary FCSs according to the startup sequence, and controlling another or more of the FCSs to mask the associated power changes while each of the auxiliary FCSs is performing a startup operation. Attached Figure Description

[0055] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the disclosure and, together with this specification, serve to explain the principles of the disclosure.

[0056] Figure 1 This is a schematic perspective view of a dynamic power distribution system conceivable herein for facilitating the power supply of devices, which are shown as vehicles for illustrative and non-limiting purposes.

[0057] Figure 2 It is a non-limiting example of n FCSs that can be selectively combined in response to instructions from a scalable array controller to individually and / or collectively provide power to the output.

[0058] Figure 3 This is a flowchart describing a power allocation method associated with a non-limiting aspect of this disclosure.

[0059] Figure 4 The diagram illustrates a start-stop sequence used to control the startup and shutdown of the FCS based on dynamic ranking and power demand.

[0060] The accompanying drawings are not necessarily drawn to scale and may present slightly simplified representations of various features of the present disclosure as disclosed herein, including, for example, specific dimensions, orientations, positions, and shapes. Details associated with such features will be determined in part by the specific intended application and environment of use. Detailed Implementation

[0061] This disclosure may be implemented in many different forms. Representative examples are shown in various figures and are described in detail herein as non-limiting representations of the disclosed principles. For this purpose, elements and limitations described in the abstract, introduction, summary, and detailed description sections but not expressly set forth in the appended claims should not be incorporated into the claims individually or collectively by implication, inference, or otherwise. Furthermore, unless specifically denied, the use of the singular includes the plural, and vice versa; the terms “and” and “or” should be conjunctions and antonyms; “any” and “all” should both mean “any and all”; and the words “including,” “comprising,” “including,” “having,” etc., should mean “including but not limited to.”

[0062] Similar terms (such as “about,” “almost,” “basically,” “roughly,” “approximately,” etc.) may be used herein in the sense of “within,” “close to,” or “almost within,” or “within 0-5%,” or “within acceptable manufacturing tolerances,” or logical combinations thereof. Similarly, as used herein, a component “configured” to perform a specified function is capable of performing the specified function without alteration, rather than having the potential to perform the specified function only after further modification. In other words, the described hardware, when explicitly configured to perform the specified function, is specifically selected, created, implemented, utilized, programmed, and / or designed for the purpose of performing the specified function.

[0063] In the following text, the term "battery" means a device comprising multiple interconnected electrochemical units (battery cells) arranged in series and / or parallel, and may also refer to battery cells grouped together (e.g., stacked) to form battery modules and / or battery packs. The term "vehicle" is used primarily for illustrative purposes, as contemplated systems are similarly applicable to electrically driven devices, including equipment, etc. For ease of description, spatially relative terms (such as "inside," "outside," "below," "under," "lower," "above," "upper," etc.) may be used herein to describe the relationship between one element or feature and another as illustrated in the accompanying drawings. In addition to the orientations depicted in the drawings, spatially relative terms may be intended to include different orientations of devices or systems in use or operation.

[0064] Referring now to the accompanying drawings, throughout several views, similar reference numerals denote similar features. Figure 1 This is a schematic perspective view of a dynamic power distribution system 10 for facilitating power supply to device 14, which is shown as a vehicle for illustrative and non-limiting purposes. Device 14 can be a mobile platform, such as, but not limited to, passenger cars, SUVs, light trucks, heavy vehicles, ATVs, minivans, buses, transit vehicles, bicycles, mobile robots, agricultural implements (e.g., tractors), sports-related equipment (e.g., golf carts), boats, aircraft, and trains. Alternatively, device 14 can be a non-mobile platform or fixed infrastructure, including but not limited to electronic / computing devices, manufacturing equipment, commercial, industrial, and residential power supplies, a piece of heavy equipment, a stationary power plant, or other consumable devices. It should be understood that the device can take many different forms and have additional components, and the drawings are not necessarily drawn to scale; for example, the scaling may not explicitly indicate the size and range of the power distribution system 10, especially when used with devices that depend on high power or megawatt power types.

[0065] The exemplary power distribution system 10 is primarily described in relation to coordinating the operation of a fuel cell power plant (FCPP) 11 to meet the electrical energy demands of associated loads, which in the illustration can correspond to providing sufficient electrical energy to operate traction motors and / or other vehicle components 13 / to power them. As with the exemplary device, the load 13 can take many forms and consist of more than one consuming device; for example, the load 13 can be a power grid or another type of network associated with distributing electrical energy to multiple components. Accordingly, the load is not specifically represented and only describes the intended recipients, many of which are capable of issuing demands or otherwise requesting power from the FCPP. System 10 schematically illustrates an output 15 for providing electrical energy to the load 13, as numerous interfaces, buses, etc., can be used to connect the FCPP 11 together or facilitate electrical connections to the FCPP 11.

[0066] Demands and similar requests, instructions, commands, etc., for loading or otherwise requesting power from distribution system 10 may be made by a suitable entity associated with device 14, which is described with respect to host controller 17 for illustrative purposes. Host controller 17 may include a processor and memory, wherein the memory includes a plurality of non-transitory instructions sufficient, when executed by the processor, to calculate total charge, voltage, current, and / or combinations thereof to support or otherwise express the power demand of load 13. Host 17 may communicate this information to scalable array controller 19, whereby a processor operating thereon, in cooperation with the execution of the corresponding non-transitory instructions stored in the included memory, processes the instructions in a manner conceivable herein and controls power distribution to facilitate the distribution of electrical energy from one or more fuel cell systems (FCS) 21, shown as 21(1)-(n), to load 13.

[0067] Because the energy storage density associated with fuel cells and / or fuel cell stacks included therein is particularly well-suited and scalable to deliver megawatts of power to loads, this disclosure is primarily described with respect to the electrical energy source being FCS 21. However, its use and application in facilitating power distribution from other electrical energy sources are entirely conceivable, including, but not limited to, batteries of a type capable of facilitating the combination of their output in a manner sufficient to meet high power demands (if not megawatt demands). This disclosure provides methods and processes designed to account for differences resulting from use, degradation, deterioration, tolerance creep, wear and damage, replacement, repair, and other unpredictable or unforeseeable types of effects. Therefore, while this disclosure can be used with batteries or other electrical energy sources, the operations conceivable herein specifically take into account the long-term differences to which FCSs are particularly susceptible.

[0068] One susceptibility unique to FCS, or at least more pronounced in FCS than in batteries, is startup ripple, experienced during the transition from an inoperable or non-powered, off state to an operating or power-operating state (i.e., the duration of fluctuation in the periodic stretch between when the FCS is activated or commanded to begin providing power and when the FCS eventually stabilizes and provides a consistent amount of available power). Startup ripple is typically associated with the FCS providing more or less power than the target or requested power; for example, the FCS may temporarily deviate above or below the expected output threshold during startup. (Even when not providing the expected available output power, the FCS can maintain a degree of operation to preserve telemetry and other features expected to be activated.) Another such susceptibility is the tendency of FCS to experience shutdown ripple, at least similarly to batteries, i.e., a temporary persistence of a certain power level during the transition from an operating state to a off state. FCS may also experience fluctuations in output capability, such as providing more or less power than requested due to degradation or other changes over time.

[0069] The construction of FCS 21 may differ, and therefore, Figure 2 This is a non-limiting example of n FCSs that can selectively combine in response to instructions from the scalable array controller 19 to individually and / or collectively provide power to the output 15. Relatedly, Figure 2 Each of the FCS 21 schematically illustrates a fuel cell assembly 12, which has a fuel cell stack 16 and associated components typically housed within an encapsulation or housing. The fuel cell stack 16 includes a plurality of membrane electrode assemblies 17 stacked together, each membrane electrode assembly 17 having a corresponding membrane M sandwiched between a corresponding anode A and a corresponding cathode C. It should be understood that the membrane electrode assembly 17 may include other layers or packing not shown. The fuel cell stack 16 receives hydrogen reactant gas from a source 18, which flows into the anode side of the fuel cell stack 16 via an anode inlet line 20. The hydrogen dissociates at the corresponding anode A to produce free protons and electrons. The protons pass through the corresponding membrane M to the corresponding cathode C. The fuel cell stack 16 produces anode exhaust gas, which is removed via an anode outlet line. The fuel cell assembly 12 may include a vent valve 24 to regulate the removal of the anode exhaust gas.

[0070] Compressor 26 is adapted to supply airflow to the cathode side of fuel cell stack 16 via cathode inlet line 28. Protons react with oxygen (in the airflow) and electrons in the corresponding cathode C to generate water. Electrons from the corresponding anode A cannot pass through the corresponding membrane M and are directed through the load to do work. Cathode outlet line 32 is used to discharge cathode exhaust gas from fuel cell stack 16. Fuel cell assembly 12 may include bypass valve 34 in communication with water vapor delivery unit 30. Bypass valve 34 is adapted to selectively redirect cathode exhaust gas through or around water vapor delivery unit 30 for humidifying cathode inlet air. Water recovered from cathode exhaust gas flow can be returned to fuel cell stack 16 via cathode inlet line 28. Excess water can also be directed to water tank 36. Fuel cell stack 16 receives cooling fluid, referred to herein as stack coolant, through coolant circuit 38 connected to coolant pump 40. Stack coolant flows through flow channels (not shown) in fuel cell stack 16.

[0071] The fuel cell membrane operates at a controlled hydration level, ensuring that the ionic resistance across the respective membrane M is sufficiently low to efficiently conduct protons. During operation of the fuel cell assembly 12, a model can be used to estimate the amount of water in the fuel cell stack 16 based on stack operating parameters. The amount of water in the fuel cell stack 16 can also be assessed using a high-frequency resistance circuit 42, which measures the high-frequency resistance of the respective membrane M. The resistance of the high-frequency component indicates the humidification level λ of the fuel cell stack 16. When the fuel cell assembly 12 is shut down or started up, it is desirable for the respective membrane M to have a hydration level within a specific range, such that it is neither too wet nor too dry. If the fuel cell stack 16 contains too much water since a previous shutdown, the water generated during a long start-up period may block gas flow channels in the fuel cell stack 16. Excess water can be removed by purging the fuel cell stack 16, where an airflow passes through the fuel cell stack 16 and the flow field. Water vapor is then diffused from the wet / humidified membrane to the dry airflow, causing the respective membrane M to dry out.

[0072] The controller 50 has at least one processor 52 and at least one memory 54 (or a non-transitory tangible computer-readable storage medium) on which instructions for facilitating the operations described herein are recorded. The memory 54 may store executable instructions, and the processor 52 may execute the instruction set stored in the memory 54. Sensors S, 44, 46 may communicate with the controller 50 via a network 60, which may be a short-range or long-range network. The network 60 may be a communication bus, which may be in the form of a Serial Controller Area Network (CAN-BUS). The network 60 may be a wireless local area network (LAN) linking multiple devices using a wireless distribution method, a wireless metropolitan area network (MAN) connecting several wireless LANs, or a wireless wide area network (WAN) covering a large area such as a neighboring town or city. The scalable array controller 19 may utilize the network to facilitate communication with the FCS 21, including performing sensing and other calculations associated with determining accompanying operational capabilities.

[0073] Figure 3 This is a flowchart 70 describing a power distribution method associated with a non-limiting aspect of this disclosure. The method can be implemented through the corresponding execution of instructions stored within the host controller 17, the scalable controller 19, and / or the FCS 21 or other processing elements included within the device. Numerous processes, operations, and other procedures are contemplated to facilitate the control of power distribution among multiple FCS 21 based on the required load and the availability of power provided by the distribution system. The related functions are primarily actions taken relative to the scalable array controller and described according to the illustrated sequence; however, this is for illustrative purposes and is not intended to limit the scope and implications of this disclosure, particularly regarding the order and / or entities responsible for the functions, as related actions can be facilitated by other entities, including those remotely operated and / or independent of the power distribution system and / or the devices requesting power.

[0074] Power distribution operation 72 relates to a scalable array controller implementing power supply operations. In an exemplary case where electrical energy is distributed from independently operable fuel cells or power supply cabinets, the power supply operation includes coordinating the operations of multiple FCSs. Coordination of the FCSs may include a power demand operation 74 and a ranking operation 76. Power demand operation 74 corresponds to a power request issued by the host controller, load 13, or other entity desiring electrical energy. The amount of power or other parameters associated with its delivery may be included in the demand. Where the FCS is an energy source, and energy cannot be stored or otherwise received from other sources, the demand is a positive value or a value indicating the need to draw energy from the FCS. Optionally, the FCS may be coordinated with batteries or other smoothing elements to facilitate the manipulation of energy flowing from them; however, such coordination may be omitted from the demand, or it may be added to the demand, resulting in the demand substantially effectively representing the total energy desired to be obtained from the FCS.

[0075] One aspect of this disclosure is conceivable in that power distribution operation 72 is used to select the FCS considered to be in the optimal position to meet demand. Additional FCSs may be added as needed when demand exceeds the capacity of a single FCS, or when the currently operating FCS requires assistance, and / or when it is desired to distribute the load across more FCSs, such as to achieve efficiency or improve degradation. Without limiting the scope as conceivable herein, the FCS considered to have the maximum power delivery capacity may be considered the primary FCS, and one or more additional FCSs used in conjunction with it may be identified as auxiliary FCSs. The power and capacity of the FCSs can be determined according to ranking operation 76, whereby the scalable array controller generates a ranking order based on information collected as part of power capability operation 78. Power capability operation 78 may correspond to the scalable array controller monitoring sensors and other operating states of multiple FCSs and making a corresponding determination of the individual capacity of each FCS.

[0076] The ranking, or more specifically, sorting, of FCSs can be implemented dynamically in real time, enabling continuous monitoring of FCS capacity. If the relative ranking changes, the sorting is adjusted accordingly, allowing the scalable array controller to track and monitor changes in FCS capacity. This capability can facilitate adaptation to FCS changes throughout the expected long lifespan, and particularly enable self-adjustment during FCS maintenance, replacement, and other changes. The ranking and other processes conceivable herein can optionally be implemented in software or within the logic processing of the scalable array controller, eliminating the need for skilled technicians to adjust rankings after maintenance or replacement. Dynamic ranking effectively enables the scalable array controller to maintain up-to-date statistics and decision-making information for FCSs throughout the entire lifespan of the power distribution system, thereby coordinating FCS activity relative to desired thresholds. For example, FCSs can be selected based on metrics associated with achieving maximum efficiency, maximum throughput, minimum degradation, etc., to meet specific requirements.

[0077] For example, the ranking process 76 can be based on multiple metrics, such as, but not limited to, active failures, available power, used power, efficiency, thermal management, degradation, and so on. Statistical analysis performed when ranking FCSs can help account for many factors influencing FCS variations, even when FCSs are shared within the same equipment or used to power the same load. For instance, an FCS on one side of the equipment (such as the side more frequently exposed to sunlight) may experience different degradation and performance characteristics compared to an FCS on the other side. Similarly, FCSs located close to certain components of the equipment may experience different conditions and environments than those located elsewhere, and / or some FCSs may have less reliability or tolerance maintenance due to manufacturing variations. Ranking operations are particularly helpful when coupled with other processes described herein to adapt the distribution system to these variations without requiring software updates or other significant operations; that is, the methods conceived herein can self-tune according to the current capacity of the FCSs.

[0078] Power demand operation 74 and ranking operation 76 can be implemented on a substantially continuous basis, allowing the allocation system to adjust to changes in FCS performance as quickly as possible, and optionally, the operations can be implemented on a cycle-by-cycle basis whenever the system or individual controllers therein perform calculations. Thus, power allocation operation 72 is capable of making power supply adjustments whenever changes in demand and / or ranking are determined. If the physical infrastructure or transition capabilities of the FCSs limit switching between FCSs or otherwise restrict power delivery, those constraints can be compensated for by correspondingly limiting hysteresis and bounce between FCSs. Power allocation operations may include generating a startup sequence and a shutdown sequence to control the startup and shutdown of FCSs accordingly. The startup sequence can incrementally indicate the ordering of FCSs (e.g., from largest to lowest) based on their power capabilities, such that the FCS listed first in the sequence is designated as the primary FCS and targeted for first use, and the remaining FCSs are designated as secondary FCSs and targeted for subsequent sequential use. In the case where FCSs are arranged in an incremental capacity order, the shutdown sequence can be similar, but in reverse of the startup sequence, the shutdown sequence can be used to start the shutdown ordering from the lowest-ranked FCS.

[0079] Decision operation 82 involves determining whether multiple FCSs are needed to meet demand and whether the primary FCS is already providing power. If the primary FCS can meet the demand, a control operation 84 can be implemented, such as activating the primary FCS if it starts from a cold stop, or continuing corresponding control of the primary FCS to meet the demand if it is already running. If the primary FCS is already running and its ranking has changed so that the running primary FCS is no longer ranked as the primary FCS, the control operation switches to another higher-ranked FCS. When multiple FCSs are needed and the primary FCS is already running, decision operation 86 occurs. As can be seen, for the sake of explanation, decision operation 86 assumes that the primary FCS is already running, such as due to the initial start or initialization of the distribution system from a cold stop. However, this may be a design requirement associated with starting the primary FCS first and is exemplary, as it is entirely conceivable in this disclosure to start multiple FCSs simultaneously, optionally at least initially, with two additional FCSs designated to act consistently as the primary FCS.

[0080] The initiation of auxiliary operation 88 involves a decision operation 86 indicating that one or more auxiliary FCSs are needed to help the main FCS meet its requirements, or that additional auxiliary FCSs need to be added if a number of auxiliary FCSs are already running. One aspect of this disclosure is conceivable in implementing the initiation of auxiliary operation 88 according to the initiation order, such that one or more auxiliary FCSs to be added are initiated sequentially, one after another. This could include, for example, initiating the highest-ranking auxiliary FCS after the main FCS has completed its initiation, and then initiating the next auxiliary FCS after the previous FCS has completed its initiation, until another FCS is initiated. This disclosure is conceivable with n FCSs, such that the initiation of auxiliary operation 88 could include looping through n initiation sequences until the requirements are met. The initiation of an auxiliary FCS can be implemented together with the previous FCS (i.e., the main FCS or the previous auxiliary FCS in the sequence), thereby implementing a masking operation to account for initiation changes associated with the FCS currently undergoing initiation.

[0081] Masking operations correspond to the FCS immediately preceding the currently activated FCS compensating for the energy supplied by activating the FCS, for example, by providing a supplementary amount of additional power equal to the difference between the FCS and the preceding FCS. For example, the activated FCS can be controlled to provide a target power amount, i.e., a portion or percentage of the total power demand; however, during startup (i.e., from the start of startup to its completion), the FCS may temporarily provide more or less power than the target amount. This deviation from the target power amount of the activated FCS affects the distribution system, causing it to receive more or less power than expected. Masking operations can also correspond to the preceding FCS compensating for the activated FCS's inability to meet its target power; for example, after startup is complete, the activated FCS may still be unable to meet its target power due to operational problems or other factors. By controlling the preceding FCS to correspondingly increase or decrease its power, i.e., provide a supplementary amount of power, the masking operations conceivable herein address the variations associated with the activated FCS and the FCS's inability to provide the target power amount once activated.

[0082] After the auxiliary operation 88 is completed, for example, after the required FCS is started and / or when the auxiliary FCS is no longer needed, a decision process 90 regarding the reordering of FCSs is performed. A reordering process 92 occurs when, for example, in response to a recent ranking operation determining that another FCS should become the primary FCS or when the auxiliary FCS is no longer determined to be reordered based on a previous ranking operation (e.g., the FCS order has changed due to a corresponding change in operational capability), a reordering process 92 is performed. The reordering operation 92 may include switching the power supply requirements of each FCS according to the ranking change, such that the changed FCS replaces the replaced FCS accordingly; that is, the changed FCS changes its target power to the target power of the replaced FCS and the amount of supplementary power provided by the FCS to mask the next ranked FCS. The FCS reordering operation 92 may help ensure that the FCS best able to meet the power supply requirements is prioritized and controlled to do so.

[0083] If no additional FCS needs to be started or no FCS reordering is required, a decision process 94 is made regarding whether any FCS needs to be shut down. For example, if power demand changes and / or the performance of one or more FCSs increases, such as in response to changes in the operating environment, it may be necessary to shut down one or more FCSs. When it is determined that one or more FCSs should be shut down, a shutdown operation 96 begins. In cases where FCSs are shut down according to their current ranking (i.e., shut down the last or lowest-ranked FCS, and then sequentially shut down each of the next lowest-ranked FCSs until the desired number of FCSs is achieved), the shutdown operation 96 can be similar to the startup operation. The shutdown operation may include a hiding operation (such as a masking operation) that controls the FCS immediately preceding the FCS to be shut down in the shutdown sequence to provide a complementary power amount when the FCS is shut down. The complementary power amount is close to the supplementary power amount used to adjust for startup changes.

[0084] Figure 4 The diagram illustrates a start-stop sequence for controlling the startup and shutdown of an FCS based on dynamic ranking and power demand. The dynamic ranking, power demand, and startup / shutdown operations associated with flowchart 110 can be implemented as described above and represent an exemplary method for calculating the total power demand and the individual power demand for each FCS (including power demands associated with compensating for or supplementing startup, shutdown, and operational differences). The start-stop sequence is described with respect to n FCSs, and the associated power supply commands vary as the FCSs are started and shut down according to their ranking and other assumptions discussed herein.

[0085] Box 112 relates to the ranking of FCSs generated from highest to lowest power supply capabilities, and then the startup of the main FCS, which can be considered the startup main state (StupP). Box 114 relates to the main FCS completing startup and reaching a normal or expected operating state, which can be considered the running main state (RunP) with the following power settings:

[0086] P Pri Req = P Req

[0087] P Sec Req = 0

[0088] Where P Req P represents the total power request of the distribution system. Pri Req This indicates the power request for the main FCS, and P Sec Req This indicates a power request to the top-ranked auxiliary FCS.

[0089] Box 116 relates to the initial startup operation for the first auxiliary FCS, which can be considered as a startup auxiliary (1) state (StupS1) with the following power settings:

[0090] P Pri Req = P Req + P Sec Req – P Sec FB

[0091] P Sec Req = 0

[0092] Where P Sec FB This represents the amount of power feedback used to adjust the power difference when the first auxiliary FCS is undergoing startup, which is considered equal to the supplementary amount as mentioned above.

[0093] Box 118 relates to the first-ranked auxiliary FCS completing startup, thus achieving the desired operating conditions, which can be considered as the running auxiliary (1) state (RunS1) with the following power settings:

[0094] P Pri Req = (P Pri UpLim / (P Pri UpLim + P Sec UpLim ))*P Req + (P Sec1 Req – P Sec1 FB )

[0095] P Sec1 Req = (P Sec1 UpLim / (P Pri UpLim + P Sec1 UpLim ))*P Req

[0096] Where P Pri UpLim It is the upper limit of power obtainable from the main FCS, and P Sec1 UpLimThis is the upper limit of the power available from the auxiliary (1) FCS. In this box, both the primary and auxiliary (1) FCS operate at the desired levels accordingly, each providing a percentage of the total power demand based on its associated power upper limit. The primary FCS also maintains, as needed, the supplementary power amount defined in the previous box to compensate for the power difference of the auxiliary (1) FCS.

[0097] Box 120 illustrates Startup Assist (n) FCS, which can be considered as a Startup Assist (n) state (StupSn) with the following power settings:

[0098] P Pri Req = (P Pri UpLim / P Total UpLim )*P Req + (P Sec1 Req – P Sec1 FB )

[0099] P Sec1 Req = (P Sec1 UpLim / P Total UpLim )*P Req + (P Sec2 Req – P Sec2 FB )

[0100] * * * * *

[0101] P Secn-1 Req = (P Secn-1 UpLim / P Total UpLim )*P Req + (P Secn Req – P Secn FB )

[0102] P Secn Req = 0

[0103] Where P Total UpLim = P Pri UpLim + P Sec1 UpLim + …..PSecn UpLim .

[0104] Box 124 illustrates that the auxiliary (n) FCS has completed startup, thus reaching the desired operating conditions. This can be considered as the run auxiliary (n) state (RunSn) with the following power settings:

[0105] P Pri Req = (P Pri UpLim / P Total UpLim )*P Req + (P Sec1 Req – P Sec1 FB )

[0106] P Sec1 Req = (P Sec1 UpLim / P Total UpLim )*P Req + (P Sec2 Req – P Sec2 FB )

[0107] * * * * *

[0108] P Secn-1 Req = (P Secn-1 UpLim / P Total UpLim )*P Req + (P Secn Req – P Secn FB )

[0109] P Secn Req = (P Secn UpLim / P Total UpLim )*P Req

[0110] Box 126 illustrates the start of the auxiliary (n) FCS shutdown operation, which can be considered as the shutdown auxiliary (N) state (ShdnSn) with the following power settings:

[0111] P Pri Req = (PPri UpLim / P Total UpLim )*P Req + (P Sec1 Req – P Sec1 FB )

[0112] P Sec1 Req = (P Sec1 UpLim / P Total UpLim )*P Req + (P Sec2 Req – P Sec2 FB )

[0113] * * * * *

[0114] P Secn-1 Req = (P Secn-1 UpLim / P Total UpLim )*P Req + (P Secn Req – P Secn FB )

[0115] P Secn Req = 0

[0116] Once the auxiliary FCS (excluding the auxiliary (1) FCS) is shut down according to the shutdown sequence, the process returns to box 118, where the main FCS can then be controlled at the box to power the remaining power supply after shutting down the auxiliary (1) FCS. Box 128 can be referred to as the shutdown of the auxiliary (1) FCS (ShdnS1) with the following power settings:

[0117] P Pri Req = P Req + P Sec Req – P Sec FB

[0118] P Sec Req = 0

[0119] The detailed description and figures are intended to support and illustrate this teaching, but the scope of this teaching is defined solely by the claims. While some preferred modes and other embodiments for carrying out this teaching have been described in detail, various alternative designs and embodiments exist for practicing the teaching as defined in the appended claims. Furthermore, this disclosure explicitly includes combinations and sub-combinations of the elements and features presented above and below.

Claims

1. A method for dynamic power distribution in a vehicle having multiple fuel cell systems (FCS), the method comprising: Determine the power capacity of each FCS to individually supply electrical energy to the traction motor, which converts electrical energy into mechanical energy to propel the vehicle. Determine the power request of the traction motor, which represents the traction motor's demand for electrical energy. as well as To enable power supply operation to meet demand, the power supply operation includes performing a startup operation according to a startup order specified for one or more auxiliary FCSs in the FCS, the startup order being to list the auxiliary FCSs in order relative to the main FCS in the FCS, the power supply operation includes performing a startup operation individually for each of the auxiliary FCSs according to the startup order, such that each of the auxiliary FCSs begins the startup operation after the main FCS, and each auxiliary FCS thus completes the startup operation; Control the FCS to perform a masking operation to mask the startup changes of the next FCS that appears after it in the startup sequence.

2. The method according to claim 1, wherein, The startup change is equal to the startup electrical energy provided when the FCS undergoes a startup operation alone.

3. The method of claim 2, further comprising controlling the next FCS to mask startup changes by providing supplemental electrical energy equal to the startup amount.

4. The method of claim 3, further comprising controlling the FCS to operate according to a load-following mode after the startup operation is completed, the load-following mode corresponding to a target power provided by each FCS, the target power being equal to the corresponding supplementary amount plus a proportional amount, the proportional amount being a percentage determined based on the upper limit of the corresponding FCS and the total power requested in demand.

5. The method of claim 4, further comprising determining the upper limit as equal to a value specified within the power capability determined for the corresponding FCS.

6. The method of claim 4, further comprising, after completing the startup operation for each of the FCS: Controlling the last FCS to perform a shutdown operation, the last FCS listed last in the startup sequence, the shutdown operation corresponds to controlling the last FCS to stop providing the target power; and In the control startup sequence, the preceding FCS performs a hiding operation to hide the shutdown change that occurs when the last FCS performs a shutdown operation, the shutdown change being equal to the shutdown electrical energy provided by the last FCS during the shutdown operation.

7. The method of claim 6, further comprising controlling the preceding FCS to conceal the shutdown change by providing complementary electrical energy equal to the amount of shutdown.

8. The method of claim 7, further comprising controlling the previous FCS to stop providing complementary electrical energy after the last FCS completes its shutdown operation.

9. The method of claim 1, further comprising determining the startup order to align with a ranking, wherein the ranking ranks the FCSs in order based on the power capabilities determined for the FCS.

10. The method of claim 9, further comprising determining a ranking based on the sum of ranking values ​​calculated for each of a plurality of characteristics determined for the corresponding FCS.

11. The method according to claim 10, wherein, The multiple characteristics include active fault characteristics, available or usable power characteristics, efficiency characteristics, and heat capacity characteristics.

12. A dynamic power distribution system, comprising: Multiple fuel cell systems (FCS) configured to provide electrical energy; as well as A controller configured to selectively distribute electrical energy from one or more of the FCSs to a load, the controller including a processor and a memory, the memory including a plurality of non-transitory instructions, which, when executed by the processor, are configured to: Determine the load's power requirements; and To enable power supply operations to meet demand, the power supply operations include performing startup operations according to a startup order specified for one or more auxiliary FCSs in the FCS, the startup order being the order in which auxiliary FCSs are listed relative to the primary FCS in the FCS, the power supply operations include performing startup operations individually for each of the auxiliary FCSs according to the startup order, and controlling another or more of the FCSs to mask the associated startup changes while each of the auxiliary FCSs is performing a startup operation.

13. The system according to claim 12, wherein, The instructions are configured to control the FCS to mask the startup change by providing supplemental electrical energy in proportion to the startup change.

14. The system according to claim 13, wherein, The instructions are configured to control the FCS to provide a target power after the startup operation is completed, the target power being equal to the corresponding supplemental amount plus a percentage of the total power requested in the demand.

15. The system according to claim 14, wherein, The instruction is configured to be used for: Control the last FCS to perform a shutdown operation. The last FCS is the last FCS listed in the startup sequence. The shutdown operation corresponds to controlling the last FCS to stop providing the target power. as well as In the control startup sequence, the preceding FCS performs a hiding operation to conceal the shutdown change that occurs when the last FCS performs a shutdown operation. The hiding operation includes the preceding FCS providing complementary electrical energy equal to the shutdown change.

16. The system according to claim 15, wherein, The instructions are configured to control the previous FCS to stop providing complementary electrical energy once the last FCS has completed its shutdown operation.

17. The system of claim 12, further comprising a vehicle having a traction motor and a plurality of FCSs, wherein the traction motor requires at least a portion of the load.

18. The system according to claim 12, wherein, Multiple FCSs are configured to provide at least 1 megawatt of power when combined.

19. A method for controlling the allocation of multiple fuel cell systems (FCS) configured to provide megawatt-level electrical energy, the method comprising: Determine the load's electrical energy requirements; as well as To enable power supply operations to meet demand, the power supply operations include performing startup operations according to a startup sequence specified for one or more auxiliary FCSs in the FCS, the startup sequence being the auxiliary FCSs listed sequentially relative to the primary FCS in the FCS, the power supply operations include performing a startup operation individually for each of the auxiliary FCSs according to the startup sequence, and controlling another or more of the FCSs to mask the associated power changes while each of the auxiliary FCSs is performing a startup operation.

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