Fuel Cell Operating Parameters Monitoring

A system and method for monitoring the cold start status of a fuel cell to improve cold start reliability. The system has a monitoring device that tracks key parameters during cold start, like stack temperature, stack pressure, and stack current, and uses them to determine the risk of ice formation. If the stack temperature is below a certain point and the stack overpressure is above a threshold, it indicates a high risk of icing. This information can be used to adjust the fuel cell operating parameters during cold start to mitigate ice formation and improve startup success.

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A method to determine relative humidity inside a fuel cell stack without using a humidity sensor. The method involves detecting supply air parameters, like temperature and humidity, along with the air flow rate. At the cathode inlet, the same parameters are measured. Using a pre-generated map, the humidifier water flow is calculated based on the cathode inlet parameters. The relative humidity is then determined from the supply air water flow, the calculated humidifier water flow, and the cathode inlet parameters. This avoids needing an internal humidity sensor.

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Water and heat management inside a fuel cell stack without adding sensors. The method involves monitoring the stack temperature to intuitively display the temperature of all single cells in a histogram. It also monitors the stack water status and single cell water status using algorithms. This allows closed-loop control of water status and hydrogen flow based on the stack and cell temperatures.

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A digital control system for fuel cells that enables unified monitoring and control of fuel cell components during low-temperature operation. The system uses digital twin technology to create a virtual model of the fuel cell that maps to the physical cell. Sensors on the cell collect data like temperature and humidity. This data is fed into the digital twin model, which calculates optimal operating parameters for the cell based on environmental factors. The control module adjusts the cell's components accordingly. This provides accurate purging and starting procedures at low temperatures.

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Calibrating fuel cell pressure sensor offsets in large scale fuel cell systems that operate continuously without frequent shutdowns, unlike fuel cells in vehicles. The system has multiple independent fuel cell modules that can be controlled individually. It calibrates pressure sensor offsets by stopping power generation of modules that need calibration. This allows calibration without affecting overall system power output. The calibration is triggered based on monitoring offset deviations or a preset time. It prevents durability issues from miscalibrated sensors in long-running fuel cells.

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A method to distinguish between reversible fuel cell degradation mechanisms like drying out versus irreversible catalyst poisoning, based on the buildup of platinum oxide (PtOx) species. The method involves monitoring the PtOx concentration in fuel cell exhaust gas. If PtOx levels increase, it indicates catalyst poisoning due to oxide formation. However, if PtOx levels decrease, it indicates drying out due to water loss. This allows targeted recovery strategies, like humidification for drying out versus platinum regeneration for catalyst poisoning, to mitigate the specific degradation mechanism.

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Estimating the amount of condensed water in the anode of a fuel cell system and controlling a drain valve based on that estimation to prevent malfunction and stack flooding. The amount of water vapor in the anode is calculated by estimating initial water, diffusion from the cathode, purging, and recirculation during fuel cell operation. The anode water vapor is subtracted from saturated vapor at temperature to get condensed water in the trap. A drain valve opens when trap water exceeds a threshold and closes when purge amount reaches a threshold.

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Fuel cell system that accurately detects the dryness/wetness of the fuel cell and improves system performance by using a physical quantity with higher correlation to fuel cell moisture than temperature to detect dryness/wetness. When deviation from ideal moisture state is detected, a reset operation is performed to recover. This involves lowering air stoichiometric ratio after increasing pressure or vice versa to suppress fuel cell output decrease while recovering moisture.

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Correcting the offset of a hydrogen pressure sensor in a fuel cell system without opening the drain valve, which eliminates issues like excessive starting time and hydrogen emission. The method involves checking if hydrogen supply is normal, constantly supplying hydrogen, determining if the pressure sensor offset needs correction based on factors like long stop time, calculating the offset correction, and applying it during starting. This allows offset correction without drain valve opening, improves accuracy and stability, and prevents reverse voltage risk.

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Controlling humidity in a fuel cell without using humidity sensors at the cathode outlet. The method involves periodically opening a hydrogen purge valve on the anode outlet to evacuate excess water. The opening time is measured, and longer times indicate more water. This indicates high cathode humidity without needing a separate sensor. The purge time is automatically adapted based on the water amount, so only necessary purging is done. The opening time can also be used to infer cathode humidity.

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Monitoring the operating environment of a fuel cell to improve its service life by detecting abnormal conditions and isolating faulty components. The monitoring involves systematic measurement of environmental parameters like cooling system pressure, power supply voltage, and air supply pressure. This data is analyzed to generate a health index for the external operating environment of the fuel cell. It allows early detection and isolation of abnormal health conditions.

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Online measurement system for internal temperature and humidity of fuel cells that provides real-time monitoring of water and heat distribution inside the fuel cell. The system uses embedded temperature and humidity sensors in the cathode and anode gas flow fields of the fuel cell. The sensors convert the temperature and humidity data into electrical signals that are transmitted to a recording module. This allows quantitative measurement of water content without requiring transparent windows or complex imaging techniques. The system is installed inside the fuel cell during operation to provide insights into water management and performance optimization.

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Device for detecting temperature and humidity inside a fuel cell stack without wiring. The device has a detection bipolar plate with a matrix of partitions inside the stack. Each partition has an installation groove that passes through multiple partitions. Wireless sensors are inserted into the grooves to simultaneously detect temperature and humidity at multiple locations inside the stack without wiring. The sensors transmit the data wirelessly to an external receiver connected to a computer. This allows real-time monitoring of internal conditions to optimize fuel cell performance and lifetime.

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Fuel cell system with improved water management to prevent flooding and degradation while minimizing hydrogen waste. The system calculates the exact amount of water in the fuel cell stack in real time based on stack output power and a calculated maximum residual water level. This allows accurate prediction and timely discharge of water without overpurge. The controller calculates the water level using stack power data and avoids using stack hydrogen flow as a water indicator, which can overestimate water. This prevents hydrogen waste from unnecessary purging.

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A cooling control system for a fuel cell stack that cools the stack and humidifies the air supply based on the stack temperature. The system adjusts the air flow and pressure to optimize cooling and prevent overheating. It also adjusts the amount of water supplied to the stack. The control method maximizes fuel cell efficiency and performance while preventing damage from overheating.

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Estimating hydrogen concentration inside a fuel cell stack to accurately converge the hydrogen concentration on a target hydrogen concentration. The method involves predicting the initial gas amount, calculating gas crossover and purging, and estimating the current anode hydrogen concentration using the initial amount, crossover, and purging. This allows reliable estimation of hydrogen concentration in all sections, not just when current is zero, for accurate control of optimum hydrogen level.

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Real-time monitoring of the internal state of the anode side of a fuel cell with a blind-end anode to optimize purge strategies and improve system efficiency. The method uses a nonlinear dynamic model of the anode side, unscented Kalman filtering, and measurements of battery parameters, purge valve action, and anode pressure to estimate anode variables like hydrogen, nitrogen, and water vapor partial pressures. This allows real-time observation of the anode state without requiring intrusive sensors.

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Fuel cell monitoring method to accurately detect issues like catalyst degradation or reactive gas distribution failures in fuel cell stacks. The method involves estimating the water content inside each cell using impedance measurements. A reference water content estimate is derived from the stack impedance. If the individual cell estimate falls below the reference by a certain threshold, it indicates catalyst degradation or gas distribution issues. This is because water content correlates with catalyst degradation and gas distribution failures. By comparing the cell estimates to the stack reference, it allows distinguishing between these issues.

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Fuel cell system with real-time steam concentration monitoring and control to improve performance and avoid damage. A humidity sensor measures the steam content of the anode exhaust stream recycle stream. This allows continuously monitoring the steam concentration in the recycle loop. A master controller uses the sensor data to adjust recycle blower flow and valve settings to optimize fuel cell operation and prevent issues like coking due to low steam-to-carbon ratios.

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Intelligent fuel cell control system that optimizes performance and reliability of fuel cells by comprehensively monitoring and controlling factors like power output, humidity, temperature, and hydrogen supply. The system uses fuzzy logic to dynamically adjust variables based on deviations from optimal values. This allows adaptive control of factors like stack temperature, humidity, and hydrogen supply to mitigate issues like degradation, drying, and crossover.

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