Environmental Engineering Reference
In-Depth Information
Supervisory
control
Alt
TDI
S
tr
Ultra-
capacitor
storage
Power
inverter
M/G
CVT trans
& FD
High voltage
12 V
battery
dc/dc
converter
Low voltage
Figure 2.6 Toyota Motor Company ES
3
experimental hybrid vehicle
from the ultra-capacitor to the vehicle's 12 V battery. An engine driven alternator
replenishes the storage battery when the engine is running. In addition to the hybrid
functionality the vehicle's brake system also maintains grade holding during engine-
OFF periods. Cabin climate control is sustained during idle-stop by a cooling storage
device so that air conditioning is available at all times.
Ford Motor Co. has developed a series-parallel switching architecture similar
to Figure 2.5 but using a hydrogen fuelled ICE instead of a CIDI as used by the
Hino company. In the Ford Model U concept vehicle a 2.3 L I4 engine is coupled
to the hybrid M/G via a pair of hydraulically activated clutches C1 and C2
(Figure 2.5). The M/G is energized by power from a 300 V NiMH battery pack
located beneath the trunk floor pan. Hydrogen compressed gas is stored in two
cylinders located beneath the front and rear seats. The Model U has a distinctive
cross-trainer style with no B-pillar. Figure 2.7 shows the Model U in side view.
The hydrogen fuel cylinders are visible in Figure 2.7 beneath the seats but
above the floor pan. The 2.3 L I4 engine and M/G are packaged in a standard front
wheel drive package. Idle-stop start times are claimed to be in the sub-300 ms
range for seamless operation.
2.1.3 Load tracking architecture
Two final configurations of series hybrids are discussed in this section. The load
tracking series hybrid, so called because the ICE must respond to all road load
inputs, consists of an engine rated for full propulsion power and a modest electrical
energy storage. Load tracking series hybrids are locomotive drives augmented with
energy storage for dynamic events such as vehicle launch, acceleration and braking.
The second series hybrid architecture is the electrically peaking powertrain. An
