Page 28 - TeamStrunz_e_mobil_structure_study_en

Basic HTML Version

The charger can either be installed in the vehicle (on-board-char-
ging), which at this point in time is the prevalent design, or it can
be installed in the charge column as an external device (off-board
charging). Off-board-charging is usually used for fast charging.
In this case, for example, direct current for the battery is already
generated in the charge station. Depending on the concept im-
plemented, the adaptation is executed as inversion or as voltage
conversion; for which separate chargers are also necessary. The
topologies required for this are currently the subject of intensive
discussion and research, as is standardization of the charge pro-
cesses and connector systems. So-called „integrated chargers“
are an interesting development. These exploit the existing infra-
structure of converters in the vehicle for the charge process and
involve significantly lower costs. TRANSMISSION
Due to the torque characteristics of a combustion engine, conven-
tional vehicles require a clutch and transmission. Efficiency and
optimization for comfort have allowed these to become extremely
complex and expensive, the trade off is that current eight-gear au-
tomatic transmissions or dual-clutch transmissions no longer offer
any comfort disadvantages over continuously variable transmissi-
ons (CVT).
Integration of an additional electric motor for power-split hybrids
and parallel hybrids adds additional complexity in the drivetrain
and the transmission. Different automotive manufacturers are
employing different solution approaches to combine the electric
propulsion system and combustion engine: Toyota uses a single
Fig. 15: Charge and discharge curves of a lithium-ion cell at fast charge
16 Lutz (2008)
Chapter 2