Environmental Engineering Reference
In-Depth Information
Mode 3
Mode 2
Mode 1
Mode
4
Vehicle speed (mph)
Mode 5
Figure 2.17 Operational map of electromechanical transmission
Mode 5
. All deceleration events are used to replenish the vehicle battery by
regenerating in either Mode 1 or Mode 2 depending on vehicle speed. Both speeder
and torquer M/Gs act as generators.
The modern incarnation of the original TRW electromechanical transmission
system is available to the public in the Toyota Prius hybrid.
2.3.1 Power split
Power split is a dual M/G architecture depicted functionally in Figure 2.18. The
basic functionality is that of engine output shaft connected to the carrier of an
epicyclic gear set. Mechanical power is transferred to the driveline from the engine
through the planetary gear set via the ring gear to the final drive and to the wheels.
To effect this mechanical path, an electric path is split off via the MG1, or S/A,
operating as a generator so that its reaction torque is developed against the carrier.
Wheels
R
M/G
3
f
C
Gearbox
FD
ICE
S
S/A
3
f
Battery
pack
Figure 2.18 Power split single mode eCVT functional architecture
