An apparatus for converting power of a fuel cell for power generation to remove an open voltage of the fuel cell and a method thereof are provided. A power converter converts and supplies power generated by the fuel cell to a system or load. A controller maintains a current linkage to the system or load to reduce an open circuit voltage (OCV) of the fuel cell, after power generation of the fuel cell is ended. The apparatus removes the OCV of the fuel cell to reduce performance and life of the fuel cell, when the fuel cell is stopped.

An apparatus for converting power of a fuel cell for power generation to remove an open voltage of the fuel cell and a method thereof are provided. A controller links current to a system or load to reduce an open circuit voltage (OCV) of the fuel cell before power generation of the fuel cell is started, after the fuel cell is started. A power converter converts and supplies power generated by the fuel cell to the system or load. The apparatus removes an OCV of a fuel cell stack to prevent performance and life of the fuel cell from being reduced.

A system, such as for a fuel cell electric vehicle, includes a fuel cell stack (FCS) and a controller. The FCS is configured to provide, such as for vehicle propulsion, a stack power commensurate with a stack power request. The stack power is a product of a stack current of the FCS and a stack voltage of the FCS. The controller is configured to, upon the stack voltage meeting a predetermined threshold, control the FCS to increase the stack current to cause the FCS to provide an increased stack power commensurate with an increased stack power request.

The disclosure relates to a fuel cell stack and corresponding method of operating the fuel cell stack. The method comprises: determining a maximum allowable current that may be drawn from the fuel cell stack; repeatedly determining a magnitude of change to the prevailing maximum allowable current based on a prevailing allowable current ramp rate and an actual measured current of the fuel cell stack; updating the maximum allowable current according to the periodically determined magnitude of change; and controlling operating parameters of the fuel cell stack according to the prevailing maximum allowable current.

A system for a fuel cell vehicle including a plurality of fuel cell modules, a plurality of battery packs, and a controller. At least one of the plurality of fuel cell modules having a state of health (SOH) different from a corresponding SOH of other fuel cell modules. Each battery pack including a plurality of battery cells. At least one of the plurality of battery packs having a SOH different from a corresponding SOH of other battery packs. The controller is communicatively coupled to monitor and control operation of the plurality of fuel cell modules and the plurality of battery packs. The controller is configured to receive a power demand and determine a power split between the plurality of fuel cell modules and the plurality of battery packs based on an operating phase of the vehicle.

In a control device for a power converter converting electric power of a fuel cell stack, the power converter includes first and second reactors, a first switching element connected to the first reactor, and a second switching element connected to the second reactor. The second reactor is located closer to a cooling water discharge manifold than the first reactor. The control device configured to: set first and second duty cycles of the first and second switching element; and execute limit control in which, by controlling the setting of the first and second duty cycles, a second amount of heat generated by the second reactor due to a second current is limited to a value smaller than a first amount of heat generated by the first reactor due to a first current within a period of at least multiple ON-OFF cycles of the first and second switching elements.

A fuel cell system herein may include a battery configured to supply electric power to a fuel cell auxiliary device used for activating a fuel cell stack. When remaining electric energy in the battery is higher than an electric energy threshold upon activation of the fuel cell stack, a controller of the fuel cell system may start outputting current from the fuel cell stack after a fuel concentration in the fuel cell stack reaches a predetermined fuel concentration threshold, and when the remaining electric energy decreases below the electric energy threshold while the fuel concentration is being increased, the controller may start outputting current from the fuel cell stack regardless of the fuel concentration in the fuel cell stack. The current can be obtained from the fuel cell stack even when the remaining electric energy in the battery is low.

To provide a fuel cell system configured to increase fuel cell performance even at high altitude. A fuel cell system for air vehicles, wherein the fuel cell system comprises: a fuel cell, an oxidant gas system for supplying oxidant gas to the fuel cell, an altitude sensor, and a controller; wherein the oxidant gas system comprises an air compressor and a bypass flow path bypassing the fuel cell; wherein the bypass flow path comprises a bypass valve; and wherein, when the controller detects an altitude increase measured by the altitude sensor, the controller increases a rotational speed of the air compressor, and the controller increases an opening degree of the bypass valve.

Provided is a fuel cell system including: a fuel cell; a reactant gas supply section; a converter; an alternating-current superimposing unit; a phase difference deriving unit configured to derive a phase difference that is a phase lag of an alternating-current voltage relative to an alternating current in an alternating-current component output from the fuel cell; and a first inference unit. The first inference unit infers that the fuel cell is in an inappropriate wet state, when the absolute value of an amount of change in the phase difference has become equal to or larger than a predetermined criterion value immediately after the magnitude of a change in the value of at least one of parameters that are a flow rate of a reactant gas, a stoichiometric ratio, and an output current has exceeded a predetermined criterion.

A fuel cell system includes a first converter to convert power, which is output from a fuel cell stack or a battery, into power in a specific level, a second converter to convert power which is input to or output from the battery, a power relay assembly to control power flow between a super capacitor and the first converter, and a controller to control outputs of the first converter and the second converter, depending on a starting state or an operating state of the fuel cell system, and to control an operation of the power relay assembly.