BMW I01, Информация о продукте

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I01�High-voltage�Components
4.�Electrical�Machine�Electronics
67
High-voltage�power�management
The�power�management�for�the�high-voltage�electrical�system�includes�two�subfunctions:�one�for
driving�and�one�for�charging�mode.�In�driving�mode�the�energy�flows�from�the�high-voltage�battery
to�the�high-voltage�consumers�are�coordinated.�The�following�steps�are�performed�by�the�EME�and
repeated�constantly:
1 Query�of�the�power�available�from�the�high-voltage�battery�(signal�source:�SME)
2 Query�of�the�requested�power�from�the�electric�motor�(signal�source:�EDME)
3 Query�of�the�requested�power�for�climate�control�(electric�heating,�EKK,�IHKA)
4 Decision�on�the�distribution�of�the�electrical�power�and�communication�to�the�control�units�of�the
consumers.
For�charging�mode�the�task�of�the�high-voltage�power�management�is�different:�It�controls�the�energy
flow�from�outside�the�vehicle�via�the�EME�and/or�the�convenience�charging�electronics�KLE�to�the
high-voltage�battery�and�if�required�to�the�electric�heating�or�to�the�EKK.�The�procedure�constantly
repeated�in�the�EME�consists�of�the�following�individual�steps:
1 Query�of�the�available�power�from�outside�(signal�source:�LIM)
2 Query�of�the�power�which�the�high-voltage�battery�can�use�(SME)
3 Query�of�the�power�which�is�required�for�the�climate�control�(IHKA)
4 Requesting�the�necessary�power�from�the�(EME/KLE)
5 Communication�of�the�available�partial�powers�to�the�receiver�of�the�high-voltage�battery�(SME
control�unit)�and�heating�and�air-conditioning�system�(IHKA�control�unit).
The�externally�available�power�cannot�be�at�a�high�level;�it�is�restricted�by�the�power�network�and�the
EME/KLE.�Therefore,�the�available�power�must�be�queried�first�before�it�can�be�distributed.�The�high-
voltage�battery�cannot�absorb�much�power,�for�example�due�to�its�state�of�charge,�which�is�why�this
value�is�also�queried�first.�Depending�on�the�temperature�of�the�high-voltage�battery�or�on�a�heating�or
an�air-conditioning�request�by�the�driver,�the�heating�and�air-conditioning�system�also�needs�electrical
power,�whose�amount�is�the�third�important�input�signal�for�the�high-voltage�power�management�in�the
charging�mode.�Using�this�information�the�externally�requested�power�is�controlled�and�distributed�to
the�consumers.
Voltage�supply�for�other�high-voltage�consumers
The�electrical�machine�electronics�supplies�voltage�not�only�to�the�electrical�machine.�The�high-
voltage�consumers�"EKK"�and�"electric�heating"�also�receive�their�high-voltage�supply�from�the
electrical�machine�electronics.
However,�there�is�no�complex�control�function�in�the�electrical�machine�electronics.�Instead,�the
electrical�machine�electronics�serves�as�a�simple�distributor�of�the�high-voltage�direct�current�voltage,
which�is�provided�by�the�high-voltage�battery.�In�order�to�protect�the�high-voltage�cable�for�the�two
high-voltage�consumers�against�overloading�in�the�event�of�a�short�circuit,�the�electrical�machine
electronics�contains�a�high-voltage�fuse�for�the�EKK�and�a�high-voltage�fuse�for�the�electric�heating.
Both�high-voltage�fuses�have�a�nominal�current�level�of�40 A.
The�distribution�and�the�electrical�connection�of�the�fuses�are�already�shown�in�the�chapter�"High-
voltage�connections".