Environmental Engineering Reference
In-Depth Information
Fig. 6.31 Hard hybrid procedure during R40 cycle on fuel cell scooter. a electric energy profiles
instantaneously exchanged by electric drive, battery pack, and FCS with the electric bus versus
cycle length. b histogram of individual cell voltage during the steady-state FCS working
analyzed by monitoring of individual cell voltages during all the R40 cycle length.
In Fig.
6.32
b, three acquisitions corresponding to three instants of the third
acceleration phase of the R40 cycle are shown. Only at the end of the acceleration
phase (about 2 kW) an appreciable but not dangerous cell working irregularity is
observed, while a very good dynamic performance is provided by the stack during
all the other phases of the cycle. This management strategy appears to be par-
ticularly suitable for a scooter application, where weight and size issues of on
board electric energy storage systems are more stringent, suggesting to satisfy
driving range demands mainly by the fuel.
The values of efficiency obtained for the main components of the power drive
by experimental measurements are reported in Table
6.6
for R40 cycle in soft and
hard hybrid configurations. The evaluation of power train total efficiency takes
