Vehicle Concepts
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HEV operating modes
Electric driving
Combustion engine off
The combustion engine is deactivated. The electric
motor/generator drives the vehicle. In a hybrid, all
functions that are normally driven by the running
combustion engine are performed by different high-
voltage and 12V units.
Power electronics
High-voltage
battery
supplies power
Electric motor/generator runs as drive unit
Combustion engine operation
Combustion engine running
Combustion engine drives the vehicle. The high-
voltage battery is charged (depending on the charge
status). The operating point of the engine is shifted to
an efficient range.
High-voltage
battery
is charged
Electric motor/generator runs as alternator
E-boost
Combustion engine running
The electric drive motor supports the combustion
engine when there is a high load requirement.
The outputs of the combustion engine and electric
motor/generator are combined briefly.
High-voltage
battery
supplies power
Electric motor/generator runs as drive unit
Combustion engine off
Regenerative braking
The combustion engine is normally switched off. The
braking energy is converted into electrical energy by
the electric motor/generator (which is functioning as
an alternator) and stored in the high-voltage battery.
High-voltage
battery
is charged
Electric motor/generator runs as alternator
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