The fuel cell control system includes: a reactor; an air compressor, wherein the air compressor has a compressing cavity, the compressing cavity has a gas inlet and a gas outlet, a rotatable pressure wheel is disposed inside the compressing cavity, and the gas outlet is in communication with the reactor; a control flow channel, wherein a first end of the control flow channel is in communication with the gas-intake side of the pressure wheel, a second end of the control flow channel is in communication with the wheel-back side of the pressure wheel, and the control flow channel is provided with a return valve for regulating the flow rate of the control flow channel; and a central control unit, wherein the central control unit is communicatively connected to the return valve to control the opening degree of the return valve.

A fuel cell power generation system is provided with: at least one fuel cell module each of which includes a fuel cell having a fuel-side electrode, an electrolyte, and an oxygen-side electrode; at least one fuel supply line for supplying a fuel gas to the fuel-side electrode included in the at least one fuel cell module; at least one oxidizing gas supply line for supplying an oxidizing gas to the oxygen-side electrode included in the at least one fuel cell module; and a most downstream exhaust fuel gas line through which an exhaust fuel gas discharged from a most downstream module that is disposed most downstream in a flow of the fuel gas among the at least one fuel cell module flows. The most downstream exhaust fuel gas line is configured to supply the exhaust fuel gas to the oxygen-side electrode included in any of the fuel cell modules.

A fuel supply control system and method for a fuel cell are disclosed. The system includes: a fuel cell configured to receive a fuel gas and an oxidation gas and generate electric power; a recirculation line configured to circulate gas containing the fuel gas and connected to a fuel electrode of the fuel cell; a discharge valve provided in the recirculation line and configured to allow the gas to be discharged to the outside when open; a discharge amount estimator configured to estimate a discharge amount of the discharged gas based on a supply amount of the fuel gas supplied to the recirculation line, a consumption amount of the fuel gas consumed in the fuel cell, and a change in the amount of the gas in the recirculation line; an offset calculator configured to calculate the discharge amount of the gas estimated by the discharge amount estimator with the discharge valve closed, as a discharge offset; and a controller configured to control opening/closing of the discharge valve.

An air pressure in fuel cells of an electric power generation system comprising a fuel cell stack (PCS) is raised with a pressurized air cooling system with recirculation to values at least two times greater than typical values for an PCS with air cooling. The FCS is either placed in a high-pressure chamber to which air is injected, or air outgoing from the FCS is redirected via a duct back to the FCS inlet and a portion of pressurized fresh air is added thereto. The chamber or the duct is provided with a radiator by means of which circulating air heat is transferred into the external environment. Air recirculation in the chamber or the duct is effected by means of fans for cooling fuel cells. Useful capacity of electric power generation systems based on fuel cells is raised significantly, the necessity of using a humidifier is excluded, and the temperature range of fuel cell operation is expanded.

A fuel cell deterioration prevention system includes a cell voltage stability determination unit determining cell voltage stability according to a preset operating condition, a fuel cell deterioration diagnosing unit diagnosing deterioration of a fuel cell by changing and controlling a control variable pre-selected according to an operating condition and monitoring a resultant change in the cell voltage of the fuel cell, and a deterioration avoidance operation control unit performing a deterioration avoidance operation based on a diagnosis result of the fuel cell deterioration diagnosing unit.

A valve device for controlling an air flow of a fuel cell stack includes: a housing connected to the fuel cell stack and including a plurality of manifolds formed therein; a disk rotatably provided in the housing to control the air flow of the fuel cell stack; and a central shaft provided at the center of the housing to rotate the disk.

A fuel cell system including: a first fuel cell performing power generation using a fuel gas; a separation membrane separating at least one of carbon dioxide or water vapor from an anode off gas discharged from the first fuel cell; a second fuel cell disposed in the downstream of the separation membrane and performing power generation using the anode off gas, the anode off gas having at least one of carbon dioxide or water vapor separated therefrom; and a distribution channel disposed on a permeation side of the separation membrane and distributing any of the following: a raw material gas serving as the fuel gas to be reformed and used for the power generation of the first fuel cell, a cathode gas including oxygen to be used for the power generation of the first fuel cell, an anode off gas discharged from the second fuel cell, a cathode off gas discharged from the first fuel cell and to be supplied to the second fuel cell, or a cathode off gas discharged from the second fuel cell, in which at least one of permeability coefficient ratio α1 of the separation membrane or permeability coefficient ratio α2 of the separation membrane is 30 or higher.

A reaction device comprising: a first flow path to which a fuel gas is supplied; a second flow path to which a gas containing oxygen is supplied; a hydrogen permeable membrane that separates the first flow path and the second flow path and allows hydrogen contained in the fuel gas supplied to the first flow path to permeate toward the second flow path; and a catalyst that is provided in the second flow path and promotes oxidation reaction between the oxygen and hydrogen passing through the hydrogen permeable membrane, wherein the hydrogen permeable membrane comprises a barium zirconium oxide membrane.

A fuel cell system is provided that includes a fuel cell with an assembly of multiple individual cells, each of which has an anode section, an electrolyte membrane, and a cathode section, an anode gas supply, which leads to an anode gas inlet and includes a fuel cell and a fuel metering device, a cathode gas supply, and a passive anode gas recirculation device, which connects an anode gas outlet to the recirculation gas inlet of a mixer arranged in the anode gas supply. The fuel cell system is started up after a standstill in that in a first phase, the fuel cell is activated while fuel is supplied from the fuel source, and the anode recirculation is suppressed without actively blocking the anode gas recirculation device, and in a second phase, anode gas is recirculated in addition to the supply of fuel from the fuel source.

A fuel cell device with a fuel tank which has a fuel supply line which is branched into fuel portion supply lines, having a plurality of fuel cell stacks which stacks each have, on the anode inlet side, a fuel connection which is respectively fluidically connected to one of the fuel portion supply lines. Exclusively one of the fuel cell stacks is connected on the anode outlet side to a fuel recirculation line. The flow guidance of the fuel recirculation line is selected in such a way that the fuel can be returned exclusively into the fuel cell stack connected to the fuel recirculation line. Furthermore, a method for operating the fuel cell device is provided.