METHOD AND ARRANGEMENT FOR MINIMIZING NEED FOR SAFETY GASES

摘要

The focus of the invention is an arrangement for minimizing need for safety gases in high temperature fuel cell system, each fuel cell in the fuel cell system comprises an anode side (100), a cathode side (102), and an electrolyte (104) between the anode side and the cathode side, the fuel cells being arranged in fuel cell stacks (103), and the fuel cell system comprises a fuel cell system piping for reactants, and means (108) for feeding fuel to the anode sides (100) of the fuel cells. The arrangement comprises means (122) for electrical anode protection supplying a predefined voltage separately to at least two fuel cell stacks (103) or groups of fuel cell stacks (103) to prohibit oxidation of anodes (100), a source (120) of energy sufficient for providing electrical energy for at least a predetermined minimum time for said means (122) for electrical anode protection, means (124) to reduce said predefined voltage to limit anode protection current to a predefined maximum current value separately for at least two stacks (103) or groups of stacks (103), and means (126) to reliably trigger said means (122) for electrical anode protection in a situation where anode oxidation cannot be prohibited by the means (108) for feeding fuel to the anode sides (100) of the fuel cells.