BMW I01, Информация о продукте

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I01�High-voltage�Components
3.�Electric�Motor
48
In�order�to�generate�the�drive�torque�using�the�electrical�machine,�the�phase�voltages�(size,�frequency
and�phase)�have�to�be�generated�at�the�coils�of�the�electrical�machine.�This�task�is�not�completed�by
the�EDME�itself,�but�by�the�electrical�machine�electronics�EME.�Via�bus�signals�on�the�PT-CAN2�the
EDME�sends�the�requested�drive�torque�to�the�EME.�The�EME�control�unit�then�calculates�the�phase
voltages�and�the�power�electronics�of�the�EME,�which�is�located�in�its�own�housing,�generates�the
phase�voltages.
Shift-by-Wire�function
Another�important�function�of�the�drive�control�is�the�shift-by-wire�function,�which�evaluates�the
electronic�gear�selector�switch�and�other�signals,�in�order�to�simulate�the�drive�positions�of�a
conventional�automatic�transmission�(P,�R,�N,�D).
The�change�between�the�drive�positions�is�achieved�in�the�I01�the�same�way�as�in�conventional
vehicles�with�automatic�transmission�and�electronic�gear�selector�switch.�Some�important
preconditions�and�functions�are�listed�below:
• Interlock:�Change�from�P�to�another�drive�position�only�when�driving�readiness�is�switched�on
• Shift�lever�interlock:�Change�from�P�or�N�to�D�or�R�only�when�brake�pedal�is�operated�at�the
same�time
• Change�from�P�or�R�to�N�or�D�only�when�selector�lever�is�operated�at�the�same�time
• Automatic�engaging�of�P:�P�is�automatically�engaged�from�the�other�drive�positions�(at�vehicle
standstill)�if�neither�the�brake�pedal�or�accelerator�pedal�are�operated,�the�driver's�door�is
open�and�the�driver's�seat�belt�is�not�inserted�in�the�seat�belt�buckle.�P�is�also�automatically
engaged�if�the�driving�readiness�is�switched�off
• Car�wash�function:�When�the�driving�readiness�is�switched�on�engage�drive�position�N,�switch
off�driving�readiness.�N�remains�engaged.
As�the�transmission�of�the�I01�only�has�a�fixed�ratio,�there�are�no�gears�and�thus�also�no�adaptive�EGS,
no�Sport�program�and�also�no�manual�program.�The�transmission�also�has�no�clutch�to�interrupt�or
establish�the�power�transmission.�There�is�also�no�reverse�gear�in�the�transmission�of�the�I01.�The
following�table�shows�how�the�drive�control�in�the�EDME�realizes�the�individual�drive�positions:
Drive�position Activation�of�the�electrical�machine Actuator�for�parking
lock
Drive�D Direction�of�rotation�forwards,�engine�or
alternator�depending�on�accelerator�pedal
operation
Disengaged
Reverse�R Direction�of�rotation�reverse,�engine�or
alternator�depending�on�accelerator�pedal
operation
Disengaged
Neutral�N Direction�of�rotation�is�specified�by
movement�direction�of�vehicle,�torque�is
adjusted�to�0 Nm
Disengaged
Parking�P Standstill,�torque�at�0 Nm Engaged