摘要 |
A PEM-fuel-cell-stack backup electric generator (1) comprising: a fuel-cell stack (2), formed by a plurality of stacked PEM fuel cells (3) electrically connected in series for supplying electrical energy to an electrical load; a cell- voltage monitor (4) for measuring the voltage supplied by each fuel cell (3); an electrical-energy management and conditioning unit (5), connected between the fuel-cell stack (2) and the electrical load; a blower (6) for supplying the amount of air necessary for the chemical reactions that occur in the fuel cells (3); a hydrogen recirculator (7) for recirculating hydrogen between the outlet and the inlet of the fuel-cell stack (2); a hydrogen-purging device (8) for carrying out a primary purging of hydrogen at a lower flow rate, and a secondary purging of hydrogen at a higher flow rate; and a controller (10), programmed for managing operation of the electric generator (1) differently at start¬ up, at shut-down, and during normal operation thereof. |