Fuel cell system

A fuel cell system comprising:

• a fuel cell;
• a compressor for supplying an oxidant gas to the fuel cell, having a first rotational speed region within which as a rotational speed increases, a vibration becomes greater than a predetermined value, and a second rotational speed region within which as the rotational speed increases, the vibration becomes equal to or less than the predetermined value, and the first rotational speed region alternates with the second rotational speed region;
• and
• a compressor controlling means for controlling the compressor by calculating a command rotational speed for commanding the compressor based on a required amount of power generation,
• wherein the compressor controlling means prohibits the compressor from rotating at a rotational speed within the first rotational speed region, and when the command rotational speed within the first rotational speed region is calculated, the command rotational speed is changed to a rotational speed within the second rotational speed region which is above the first rotational speed region, or the command rotational speed is changed to a rotational speed within the second rotational speed region which is below the first rotational speed region.