Concepts for PEMFC applications
All systems are tested in a preliminary test phase in the
laboratory. After successful completion of those tests, they
are installed at operating sites and subjected to field tests. At
the operating sites the complete fuel cell systems are installed
in parallel with existing backup batteries. The control system
is designed to ensure that in the case of an outage the fuel
cells will be the first backup system to supply power.
Two different system versions are being tested. One
version uses a small battery to ensure uninterrupted power
supply until the 5-kW FC kicks in. In the second version, a
high-capacity capacitor ensures power supply. This capacitor
is discharged by the downstream loads, and cyclically
recharged by the 2x2.5-kW fuel cell.