BMW I01, Информация о продукте

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I01�High-voltage�Components
3.�Electric�Motor
49
The�selector�level�position�N�is�thus�not�achieved�by�opening�a�clutch�in�the�transmission.�Instead,�the
electrical�machine�is�activated�so�that�it�neither�generates�an�engine�nor�alternator�torque.�One�can
therefore�imagine�as�if�the�coils�of�the�stator�were�open�and�no�voltage�is�applied�from�outside.�There
is�in�fact�voltage,�generated�by�the�electrical�machine�electronics�–�however,�this�is�adjusted�in�the
amplitude,�frequency�and�phase�so�that�the�rotor�can�rotate�without�a�load�(torque�0 Nm).
The�difference�between�the�drive�positions�N�and�P�is�solely�in�the�condition�of�the�parking�lock
module.�In�N�it�is�disengaged,�in�P�it�is�engaged.
Power�management�function
For�historical�reasons�and�due�to�an�indirect�relation�to�the�drive�functions,�other�functions�are
integrated�in�the�drive�control�units,�especially�in�the�EDME�control�unit.
For�many�years�the�electrical�power�management�of�conventional�vehicles�has�been�integrated�as
a�function�in�the�engine�control.�The�evaluation�of�the�12 V�battery�state�of�charge�via�the�IBS�and
the�consumer�shutdown�are�examples�for�this�power�management�function.�This�tradition�is�also
continued�in�the�I01:�The�EDME�control�unit�performs�the�power�management�function�for�the�low-
voltage�vehicle�electrical�system.�The�power�management�in�the�low-voltage�vehicle�electrical�system
includes�the�following�subfunctions:
• Determination�of�the�current�energy�requirement�of�the�electrical�consumers�(signals�in�the
form�of�bus�signals,�e.g.�switch-on�status�of�exterior�lights�by�the�Body�Domain�Controller
BDC)
• Determination�of�state�of�health,�state�of�charge�and�charge�current/discharge�current�of�the
12 V�battery�(signals�from�the�IBS)
• Controling�the�power�of�the�DC/DC�converter
• Monitoring�of�the�standby�current
• Switch-off�of�terminals�or�consumers�in�order�to�protect�the�12 V�battery�against�heavy
discharge.
The�task�of�the�conventional�12 V�alternator�is�assumed�in�the�I01�by�the�DC/DC�converter�in�the
electrical�machine�electronics.�Depending�on�the�power�required,�the�power�management�in�the
EDME�requests�corresponding�power�from�the�electrical�machine�electronics�via�bus�signals.
3.3.3.�Electrical�Digital�Motor�Electronics�(EDME)
The�designation�"Electrical�Digital�Motor�Electronics�(EDME)"�reflects�the�electric�motor�in�the�I01
(in�comparison�to�the�conventional�drive�with�a�combustion�engine).�The�manufacturer�of�the�EDME
control�unit�is�"Delphi�Electronics�Group".�The�manufacturer's�internal�designation�is�"DCM 3.8"�–�this
Delphi�engine�control�unit�is�already�used�by�other�vehicle�manufacturers�and�was�adapted�for�the�I01
in�terms�of�the�electrical�interfaces.
The�installation�location�is�shown�in�the�following�graphic: