1741results about "Fuel cell control" patented technology

A fuel cell gas management system including a cathode humidification system for transferring latent and sensible heat from an exhaust stream to the cathode inlet stream of the fuel cell; an anode humidity retention system for maintaining the total enthalpy of the anode stream exiting the fuel cell equal to the total enthalpy of the anode inlet stream; and a cooling water management system having segregated deionized water and cooling water loops interconnected by means of a brazed plate heat exchanger.

Described herein are fuel cell systems and methods of using fuel cell systems. The systems include a fuel cell that generates electrical energy using hydrogen and a fuel processor that produces hydrogen from a fuel source. The fuel processor includes a reformer and a burner that heats the reformer. One heat efficient fuel cell system described herein heats internal portions of a fuel cell using a heating medium from a fuel processor. The heating medium may comprise gases exhausted at high temperatures from the fuel processor, which are then transported to the fuel cell. The heating medium may also include a gas that reacts catalytically in the fuel cell to produce heat. Systems and methods for expediting fuel cell system start up are provided. Methods for shutting down a fuel cell system are also described that reduce the amount of moisture and gases in the reformer and in one or more fuel cell components. One hydrogen efficient fuel cell system described herein transports hydrogen to an inlet of a burner. The hydrogen may comprise unused hydrogen from a fuel cell and/or hydrogen produced in a reformer. The burner comprises a catalyst that facilitates production of heat in the presence of the hydrogen.

The invention relates to hybrid fuel cell systems that protect a fuel cell with a second electrical energy source. The second electrical energy source powers a load to prevent the fuel cell from witnessing stoichiometric levels that may lead to reductions in fuel cell performance or health. The hybrid fuel cell system includes an electrical circuit that electrically initiates the electrical energy source to provide power to the load in response to detecting a potential stoichiometric disturbance for the fuel cell.

A fuel cell system is provided which estimates a water content in a fuel cell based on a predetermined map using an integrated value of electric current generated by the fuel cell (ST4) before power generation is stopped (ST5). When a temperature of the fuel cell has fallen lower than a predetermined value (ST7) after the power generation is stopped (ST5), the fuel cell system determines a dry degree in the fuel cell (ST8) and an anode scavenging period (ST9) based on predetermined maps. Scavenging is performed in an anode in the fuel cell for the anode scavenging period (ST10).

A fuel cell includes a stack of unit cells, each including: a hydrogen-ion conductive polymer electrolyte membrane; an anode and a cathode sandwiching the polymer electrolyte membrane; an anode-side conductive separator plate having a gas flow path for supplying and discharging a fuel gas to and from the anode; and a cathode-side conductive separator plate having a gas flow path for supplying and discharging an oxidant gas to and from the cathode. At least one of the anode-side and cathode-side separator plates has, in one face thereof, a plurality of independent gas flow channels, which constitute the gas flow path. When the fuel cell is operated at low load, the fuel gas or the oxidant gas is supplied to one or more of the plurality of independent gas flow channels, so that the fuel cell is capable of securing sufficient gas velocity.

A fuel cell system that includes a control system for regulating the power produced by the fuel cell system. The fuel cell system includes a fuel cell stack adapted to produce electrical power from a feed. In some embodiments, the fuel cell system includes a fuel processing assembly adapted to produce the feed for the fuel cell stack from one or more feedstocks. The control system regulates the power produced by the fuel cell system to prevent damage to, and/or failure of, the system.

A fuel cell system includes a fuel cell stack, a hydrogen flowing passage, an air flowing passage and a control valve. At least one of the gas flowing passages includes a bypass, a selecting means, a gas flowing means and a control unit. The bypass allows a gas to flow therethrough so as to detour the fuel cell stack and the control valve. The selecting means selects one of a passage which passes through the fuel cell stack and the bypass. The gas flowing means flows the gas to the bypass. In the control unit, the through passage is selected by the selecting means when the system is operated, The bypass is selected by the selecting means when the operation of the system is stopped. The gas is flowed to the bypass by operating the gas flowing means when the control valve is frozen thereby heating the control valve.

A system and method for putting a fuel cell vehicle system into a stand-by mode where there is little or no power being consumed, the quantity of fuel being used is minimal and the fuel cell system is able to quickly recover from the mode. The method includes determining whether predetermined stand-by mode vehicle level entrance criteria have been satisfied at a vehicle control level and predetermined stand-by mode fuel cell level entrance criteria have been satisfied for a fuel cell system control level, and putting the vehicle in the stand-by mode if both the vehicle level entrance criteria and the fuel cell level entrance criteria have been satisfied. The method exits the stand-by mode if predetermined vehicle level exit criteria have been satisfied or predetermined fuel cell level exit criteria have been satisfied.

The invention relates to a control method for predicting an air supply system model of a fuel cell and belongs to the technical field of control. The invention aims to provide the control method for predicting the air supply system model of the fuel cell to achieve steady operation of the system by adjusting the peroxy ratio of a proton exchange membrane fuel cell to avoid air hunger. The method comprises the following steps: S1, establishing an air supply system dynamic model of the fuel cell for high precision control; S2, determining a preoxy reference value of the proton exchange membranefuel cell system; S3, evaluating the internal pressure value of a cathode and system disturbance by adopting an expanding state observer; and S4, designing a peroxy ratio controller of the proton exchange membrane fuel cell system. By adjusting the output evaluation error in real time by using the expanding state observer and retraining the output error to zero within an infinite time, the pressure of a cathode pipeline which cannot be measured is evaluated accurately.

A method of operating a fuel cell having an anode passage. The method includes collecting hydrogen from the anode passage that does not pass through the catalyst membrane. The hydrogen, together with water and inert gases, are directed to a hydrogen storage container. The hydrogen storage container includes a hydrogen storage media such as metal hydride, carbon adsorbents, or carbon nanofibers. A sensor determines whether or not the vehicle is moving. When the vehicle is stopped or moving slowly, the surplus hydrogen is directed to the hydrogen storage container for temporary storage. When the sensor determines that the vehicle is moving at a high speed, the surplus hydrogen is vented to atmosphere and the hydrogen storage media is renewed.

A fuel cell system arrangement is disclosed for controlling an Oxygen-to-Carbon (O/C) relationship by providing water to an anode side fuel recirculation, pumping the provided water to facilitate a water flow, and evaporating water from the facilitated water flow for generating pressurized steam having at least the motive pressure for a steam jet-ejector. The at least one steam jet-ejector can inject at least part of the steam to the fuel cell system, and entrain part of an essentially low pressure anode exhaust gas stream in the anode side gas recirculation and compress the gas mixture to an intermediate pressure of the fuel feed-in stream for controlling the Oxygen-to-Carbon (O/C) relationship in the fuel side of the fuel cell system.

A molten carbonate fuel cell stack and a method of operating a molten carbonate fuel cell stack, which fuel cell comprises a porous anode, a carbonate-comprising matrix and a porous cathode, wherein the anode section is supplied with a hydrogenous gas and the cathode section is supplied with a gaseous mixture comprising oxygen and carbon dioxide, the fuel cell is operated at a temperature in a range of about 823-973 K, with the carbonate of the carbonate-comprising matrix being in a fluid state, oxygen and carbon dioxide are reacted at the cathode, yielding carbonate ions which move from the cathode to the anode generating an electric voltage between the anode and the cathode and an electrical current circulating in the external circuit and water that has been formed is led away from the fuel cell together with carbon dioxide, comprising sampling the temperature of inlet of the reactants, sampling the temperature of outlet of reactants, sampling the current density and voltage sampling the flow rate and gas composition of the inlet and outlet gases analyzing the sampled temperature, current density, voltage flow rates and gas composition, and regulating the inlet flow rate such as the pressure drop between inlet and outlet is below 20 mbar and the temperature in each element of a cell of the stack is below 973K.

A system for providing field deployable electrical power distribution is provided. The system includes a plurality of power sources providing electrical power to meet the electrical needs of a field operations camp. The power sources include at least one regenerative fuel cell that is arranged to provide a electrical power when renewable energy sources are unavailable. Also provided is at least one generator and one regenerative fuel cell electrically connected to the plurality of loads. Also provided is a plurality of power converters, each of the plurality of power converters being electrically connected between the at least one generator and regenerative fuel cell and one of the plurality of loads. An arrangement is also included for providing a high availability battery charging station.

A method utilizing the resistance of the electrolytic membrane of a fuel cell is known conventionally as a method for detecting abnormality occurring in the fuel cell. As shown on FIG. 4, resistance of the electrolytic membrane increases as the temperature thereof decreases or the moisture content thereof decreases (i.e. dry state), and decreases as the temperature increases or the moisture content increases (i.e. wet state), and thereby it was difficult to judge whether a deterioration in performance or a simple drop in performance has occurred by simply detecting an increase in resistance. A criterion for judging a deterioration in performance of a fuel cell based on the resistance of an electrolytic membrane is thereby set higher as the electrolytic membrane approaches a dry state and temperature thereof decreases and set lower as the electrolytic membrane approaches a wet state and the temperature thereof increases. Consequently, a deterioration in performance of a fuel cell can be judged easily regardless of the operating state thereof.

The temperature/humidity control system includes a humidifying device having a vibrator to convert water into vapor. The control system also includes, a storage member storing the vapor generated by the vibrator, and at least one mixing member to humidify hydrogen and air supplied to the fuel cell stack with the vapor stored in the storage member. The control system fuel cell includes a preheating device configured to preheat the hydrogen and air humidified by the mixing member, and at least one temperature sensor detecting temperatures of hydrogen and air having passed the preheating device and a temperature of coolant of the fuel cell stack. Finally, the control system includes at least one humidity sensor detecting humidities of hydrogen and air having passed the humidifying devices, and a fuel cell control unit controlling the humidifying device and the preheating device based on signals of the temperature sensor and the humidity sensor.

During a normal control (CP) having a fuel supply (3) supplying a fuel (Fg), an air supply (3) supplying an oxidizer (Og), a stack (1) of fuel cells generating power with the fuel and the oxidizer supplied, a battery (7) as a secondary cell operable for power charge and discharge, and a power distributor (4) distributing power from the stack to a main load (5) and operable for distribution of power from the stack to the battery and from the battery to the load, after a startup with the stack and the battery warmed-up, a controller (8) serves for raising a temperature (Ts) of the stack when a possible generation (Gp) of power is reduced and for raising a temperature (Tb) of the battery when a possible charge (Cp) of power or a possible discharge (Dp) of power is reduced, to maintain stable power supply to the load even under a continued low-output condition.

The invention provides a redox flow battery rebalance system, a redox flow battery system containing the same and a method for cycle capacity rebalance of a redox flow battery. The above system or method is particularly and suitably used for a Fe-Cr flow battery. The redox flow battery rebalance system has a flow battery structure, wherein a positive electrolyte storage tank of the rebalance system is used for storing a positive electrode containing active positive ions, a negative electrolyte storage tank of the rebalance system is simultaneously taken as a positive electrode storage tank of a working flow battery and is used for storing a positive electrolyte of the working flow battery, and the redox flow battery rebalance system is only used for charging after being started. With the technical scheme provided by the invention, the redox flow battery rebalance system has the advantages of high rebalance efficiency and convenience, rapidness and high efficiency in operation.

Fuel cell covers, electronic systems and methods for optimizing the performance of a fuel cell system are disclosed. In the various embodiments, a fuel cell cover includes an interface structure proximate to one or more fuel cells. The interface structure is configured to affect one or more environmental conditions proximate to the one or more fuel cells. An electronic system includes an electronic device, one or more fuel cells operably coupled to the electronic device, and an interface structure proximate to the one or more fuel cells. The interface structure affects one or more environmental conditions near or in contact with the one or more fuel cells. A method includes providing a fuel cell layer, and positioning an interface layer proximate to the fuel cell layer.

Disclosed is a segmented modular solid oxide fuel cell device having a plurality of independently controllable electrical power producing segments disposed within a common thermal environment. Also disclosed are methods for selectively operating one or more segments of the disclosed segmented modular solid oxide fuel cell device. Also disclosed are methods for performing a maintenance process on one or more segments of a segmented modular fuel cell device during fuel cell operation.

A control system for controlling the amount of water in at least one fluid stream that is passed through a fuel cell stack comprises a humidifier arrangement, a sensor and a controller. The humidifier arrangement is operable to humidify the fluid stream. The sensor is disposed downstream of the humidifier arrangement and configured to measure at least one characteristic of the fluid stream. The at least one characteristic of fluid stream is indicative of the amount of water in the fluid stream. The controller is configured to receive a signal from the sensor and to use the signal to determine a difference between an amount of water in the fluid stream and a target amount of water. The controller is operable to control the humidifier arrangement to control the amount of water in the fluid stream based on the difference.

The invention discloses a fuel cell thermal management system with heat accumulation and heating functions and a control method. The fuel cell thermal management system comprises water circulation systems including a small circulation waterway system, a large circulation cooling system, a deionized water circulation system and the like and a control system which takes an ECU (Electric Control Unit) as a core. According to the fuel cell thermal management system disclosed by the invention, the small circulation waterway system is capable of realizing a low-temperature heating function on a fuel cell by adopting a heat accumulator, so that compared with a traditional electric heater technology, the fuel cell thermal management system has the advantages that the control accuracy is higher, and the fuel cell thermal management system is more energy-saving and efficient; meanwhile, as the deionized water circulation system is adopted, an ion exchanger is skillfully designed on a degassing pipe of a large circulation waterway, a degassing function and a deionizing function of the fuel cell thermal management system are perfectly combined together, and the influence of a high-water-resistance ion exchanger in the prior art on a main circulation waterway is effectively avoided.