Fuel cell system and method for operating a fuel cell system

Abstract

The invention relates to a method for operating a fuel cell system (2) having at least one fuel cell (4) and having a compressor (16), wherein the compressor (16) is designed and provided to receive air, to compress it and to make it available to the at least one fuel cell (4) as a cathode mass flow (mf) at an increased pressure (p).The method comprises determining, from the value of a requested electrical current intensity (i) requested by a higher-level instance (9) from the at least one fuel cell (4), the cathode mass flow (mf) required to provide the requested electrical current intensity (i); determining a cathode pressure (pC) of the cathode mass flow (mf) required for low-wear operation of the at least one fuel cell (4); determining the maximum cathode pressure (pmax) of the cathode mass flow (mf) that can be provided by the compressor (16) under the current operating conditions at the determined cathode mass flow (mf); and reducing the requested electrical current intensity (i) if the cathode pressure (pC) of the cathode mass flow (mf) specified by the fuel cell (4) exceeds the maximum cathode pressure (pmax) that can be provided by the compressor (16) under the current operating conditions.

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