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.

Disclosed are a deterioration estimation system for the fuel cell, a hydrogen supply system for a fuel cell including the same, and a hydrogen supply method for a fuel cell, the deterioration estimation system including a fuel cell which receives hydrogen gas and oxidizing gas respectively supplied to an anode side and a cathode side thereof to generate electrical power, a hydrogen supply line which is connected to the anode side of the fuel cell and supplies gas containing hydrogen gas to the fuel cell, a hydrogen supply valve which is located between the hydrogen supply line and a hydrogen tank, supplies, when opened, hydrogen gas stored in the hydrogen tank to the hydrogen supply line, and blocks the supply of the hydrogen gas when closed, and a deterioration estimating unit which estimates the deterioration state of the fuel cell, based on the opening and closing control of the hydrogen supply valve or a change in the pressure in the hydrogen supply line.

The present disclosure relates to a fuel cell system including: an air supply line configured to supply air to a fuel cell stack; a discharge line connected to the fuel cell stack and configured to guide exhaust gas discharged from the fuel cell stack; a discharge adapter connected to the discharge line and configured to discharge the exhaust gas to the outside; and a bypass line having one end connected to the air supply line and the other end connected to the discharge adapter, the bypass line being configured to selectively allow the air to flow from the air supply line to the discharge adapter, thereby effectively reducing a hydrogen concentration in exhaust gas discharged from the fuel cell stack.

A method for operating a propulsion system for an aircraft, the propulsion system including a gas turbine engine and a fuel cell assembly, the fuel cell assembly including a fuel cell stack having a fuel cell defining an outlet positioned to remove output products from the fuel cell during operation, the method including: executing a startup sequence for the fuel cell assembly, wherein executing the startup sequence for the fuel cell assembly includes initiating the startup sequence for the fuel cell assembly; executing a startup sequence for the gas turbine engine, wherein executing the startup sequence for the gas turbine engine comprises initiating the startup sequence for the gas turbine engine subsequent to initiating the startup sequence for the fuel cell assembly; and operating the fuel cell assembly to provide output products to a combustion section of the gas turbine engine.

A method for operating a propulsion system for an aircraft, the propulsion system including a gas turbine engine and a fuel cell assembly, the fuel cell assembly comprising a fuel cell stack having a fuel cell defining an outlet positioned to remove output products from the fuel cell during operation, the method including: executing a startup sequence for the gas turbine engine, wherein executing the startup sequence comprises initiating the startup sequence for the gas turbine engine; executing a startup sequence for the fuel cell assembly concurrently with, or subsequent to, initiating the startup sequence for the gas turbine engine; and operating the fuel cell assembly to provide output products to a combustion section of the gas turbine engine.

The present invention relates to a sensor device (10) for a fuel cell system (100) for determining a purging parameter (SP) for controlling a purging process of the fuel cell system (100), comprising a first flow channel (20) for arranging in an anode feed section (122) of an anode section (120) of a fuel cell stack (110) and a second flow channel (130) for arranging in a recirculation section (126) of the anode section (120) of the fuel cell stack (110), which are separated from each other, at least in sections, by means of a gas-tight membrane (40), wherein the membrane (40) is designed to be permeable for protons and has an electrode section (42, 44) on both sides, as well as comprising a measuring device (50) for determining a fuel concentration difference between the first flow channel (20) and the second flow channel (30) as a purging parameter (SP) based on an electrical voltage between the two electrode sections (42, 44).

A fuel cell system includes a fuel cell stack, an anode system apparatus, a control unit, an anode outlet temperature sensor, and a purge valve. In a method of starting operation of the fuel cell system at low temperature, a control unit compares a predetermined freezing temperature threshold value with an anode outlet temperature detected by an anode outlet temperature sensor. Then, the control unit performs low temperature control to place the purge valve in the constantly open state in the case where the temperature is not higher than the freezing temperature threshold value, and performs normal control for switching opening/closing of the purge valve in the case where the temperature exceeds the freezing temperature threshold value.

A method and system of controlling hydrogen purge are provided. The method includes estimating an air supply rate supplied to a fuel cell stack and then executing hydrogen purge based on the estimated air supply rate.

An illustrative example method of controlling operation of a fuel cell power plant includes opening a pneumatic valve using pneumatic pressure of pressurized fuel cell reactant, allowing the pressurized fuel cell reactant to flow through the pneumatic valve to a cell stack assembly, determining that shutdown of the cell stack assembly is desired, and control a rate that the pneumatic valve closes by controlling a rate of release of the pneumatic pressure.

Disclosed is a method of controlling an air supply system for a fuel cell. The air supply system includes a fuel cell stack, an air channel to supply air to an inlet of the fuel cell stack, a gas adsorption unit disposed on the air channel and configured to adsorb oxygen contained in air introduced into the air channel. In particular, the method includes: determining whether a power generation operation of the fuel cell stack is resumed; when the power generation operation of the fuel cell stack is resumed, controlling a voltage source to apply a voltage to the gas adsorption unit; and supplying air to the fuel cell stack through the air channel in a state in which the voltage is applied to the gas adsorption unit.