The present disclosure relates to a fuel cell system and a method of controlling a heater thereof. A fuel cell system according to the present disclosure includes a cathode oxygen depletion (COD) heater that is disposed on a line through which cooling water flowing into a fuel cell stack circulates and heats the cooling water or consumes residual power of the fuel cell stack, and a controller that determines power consumption according to a target heating amount of the COD heater and controls an operation of the COD heater based on the determined power consumption.

Disclosed is a method and a device configured to control deterioration avoidance operation of a fuel cell system. In one aspect, the method may include starting the deterioration avoidance operation when an operation of a fuel cell is restarted in a state where an energy storage device is operating, and the fuel cell is stopped; controlling anode hydrogen pressure based on a predetermined condition, the condition indicating that the anode hydrogen pressure needs to be increased; determining hydrogen recirculation and supplying hydrogen including a process to determine whether to recirculate hydrogen based on a predetermined condition, the condition indicating that hydrogen needs to be recirculated, before supplying hydrogen; determining air recirculation and supplying air including a process to determine whether to recirculate air based on a predetermined condition, the condition indicating that air needs to be recirculated, before supplying air; and terminating the deterioration avoidance operation and starting operation of the fuel cell.

Disclosed herein is a method of controlling start/stop of a parallel fuel cell system, which, when controlling stop of a parallel fuel cell system in which two or more fuel cell systems are connected in parallel, considers operating state information of each fuel cell system, such as a current speed value of an air compressor and an opening degree of an air-exhaust-side air pressure valve of a fuel cell stack. Accordingly, the method can calculate a delay time for performing fuel cell system stop control for the two or more fuel cell systems, and sequentially perform the fuel cell system stop control for the two or more fuel cell systems based on the calculated delay time. Therefore, it is possible to minimize output delay of each fuel cell system and to achieve deterioration prevention and efficiency improvement of the fuel cell stack by fuel cell system start/stop control.

Disclosed herein is a method of controlling start/stop of a parallel fuel cell system, which, when controlling stop of a parallel fuel cell system in which two or more fuel cell systems are connected in parallel, considers operating state information of each fuel cell system, such as a current speed value of an air compressor and an opening degree of an air-exhaust-side air pressure valve of a fuel cell stack. Accordingly, the method can calculate a delay time for performing fuel cell system stop control for the two or more fuel cell systems, and sequentially perform the fuel cell system stop control for the two or more fuel cell systems based on the calculated delay time. Therefore, it is possible to minimize output delay of each fuel cell system and to achieve deterioration prevention and efficiency improvement of the fuel cell stack by fuel cell system start/stop control.

A power generation control system includes a plurality of fuel cell systems mounted in an electric device that operates using electric power, a battery mounted in the electric device, and a control device configured to control each of the plurality of fuel cell systems on the basis of states of the plurality of fuel cell systems, a state of the battery, and required power of the plurality of fuel cell systems.

A power generation control system includes a plurality of fuel cell systems mounted in an electric device that operates using electric power, a battery mounted in the electric device, and a control device configured to control each of the plurality of fuel cell systems on the basis of states of the plurality of fuel cell systems, a state of the battery, and required power of the plurality of fuel cell systems.

A method of controlling a fuel cell device includes: a step of purging a hydrogen supply unit of a fuel electrode and purging a gas supply unit of an oxidant electrode when an operation of the fuel cell device ends; a step of measuring a voltage between the fuel electrode and the oxidant electrode and determining whether the voltage is greater than a predetermined threshold; a step of continuing power generation in the fuel cell device when the voltage is greater than the predetermined threshold; and a step of depressurizing the hydrogen supply unit and the gas supply unit when the voltage is equal to or less than the predetermined threshold.

Introduced is an fuel cell power net including a fuel cell configured to generate power through a reaction between a fuel gas and an oxidizing gas, a power storage device configured to be charged with power generated by the fuel cell or discharged to supply power, a main line configured to electrically connect the fuel cell and the power storage device to each other; a main relay disposed on the main line so as to break or make an electrical connection between the fuel cell and the power storage device, a bypass line which is branched from the main line, bypasses the main relay, and is connected to the power storage device, a bypass relay disposed on the bypass line so as to break or make an electrical connection of the bypass line, and a controller configured to control the main relay or the bypass relay such that the power stored in the storage device is supplied to the fuel cell while the power generation of the fuel cell is stopped.

Disclosed are a method of improving fuel efficiency of a fuel cell electric vehicle, and an apparatus and a system therefor. The method includes collecting navigation information and vehicle speed information, calculating a coasting line when a specified event point is detected based on the navigation information, determining whether deceleration is necessary by comparing a current traveling speed with a coasting line speed corresponding to a current location, and changing a criterion for determining whether to enter a fuel cell stop (FC STOP) state when the deceleration is necessary as a determination result.

Disclosed are a method of improving fuel efficiency of a fuel cell electric vehicle, and an apparatus and a system therefor. The method includes collecting navigation information and vehicle speed information, calculating a coasting line when a specified event point is detected based on the navigation information, determining whether deceleration is necessary by comparing a current traveling speed with a coasting line speed corresponding to a current location, and changing a criterion for determining whether to enter a fuel cell stop (FC STOP) state when the deceleration is necessary as a determination result.