Introduction - BMW I01 Product Information

I01￿High-voltage￿Components
4.￿Electrical￿Machine￿Electronics
4.1.￿Electrical￿machine￿electronics￿(EME)
4.1.1.￿Introduction
The￿electrical￿machine￿electronics￿EME￿serves￿mainly￿as￿control￿electronics￿for￿the￿electrical￿machine,
which￿drives￿the￿I01.￿It￿assumes￿the￿task￿of￿converting￿the￿DC￿voltage￿(up￿to￿about￿400 V￿DC)￿from
the￿high-voltage￿battery￿into￿a￿three-phase￿AC￿voltage￿(up￿to￿about￿360 V￿AC)￿for￿activating￿the
electrical￿machine￿as￿a￿motor.￿Vice￿versa,￿when￿the￿electrical￿machine￿works￿as￿an￿alternator,￿the
electrical￿machine￿electronics￿converts￿the￿three-phase￿AC￿voltage￿of￿the￿electrical￿machine￿to￿a
direct￿current￿voltage￿and￿can￿thus￿charge￿the￿high-voltage￿battery.￿This￿takes￿place￿during￿brake
energy￿regeneration.￿For￿these￿two￿operating￿modes￿a￿bidirectional￿DC/AC￿converter￿is￿necessary
which￿can￿work￿as￿both￿an￿inverter￿and￿a￿rectifier.
The￿DC/DC￿converter￿which￿is￿also￿integrated￿in￿the￿electrical￿machine￿electronics￿ensures￿the￿voltage
supply￿to￿the￿12 V￿vehicle￿electrical￿system.￿The￿electrical￿machine￿electronics￿has￿another￿control
unit￿which￿bears￿the￿same￿name,￿"EME"￿for￿short.
The￿entire￿electrical￿machine￿electronics￿of￿the￿I01￿is￿located￿in￿an￿aluminium￿housing.￿The￿control
unit￿of￿the￿bidirectional￿AC/DC￿converter￿for￿the￿conversion￿of￿the￿AC￿voltage￿to￿direct￿current￿voltage
for￿charging￿the￿high-voltage￿battery,￿as￿well￿as￿conversion￿of￿the￿direct￿current￿voltage￿from￿the￿high-
voltage￿battery￿to￿3-phase￿AC￿voltage￿and￿the￿DC/DC￿converter￿for￿the￿voltage￿supply￿of￿the￿12 V
vehicle￿electrical￿system￿are￿located￿in￿this￿housing.
The￿housing￿of￿the￿electrical￿machine￿electronics￿cannot￿be￿opened￿in￿Service.
The￿electrical￿machine￿electronics￿of￿the￿I01￿is￿developed￿and￿supplied￿by￿the￿relevant￿departments￿of
BMW￿AG.￿The￿production￿is￿carried￿out￿in￿a￿division￿of￿the￿plant￿in￿Dingolfing.
Only￿Service￿employees￿who￿satisfy￿all￿the￿prerequisites￿are￿permitted￿to￿work￿on￿the￿designated
high-voltage￿components:￿suitable￿qualifications,￿compliance￿with￿the￿safety￿rules,￿procedure
following￿the￿exact￿repair￿instructions.
The￿diagnosis￿and￿repair￿of￿the￿high-voltage￿components￿is￿only￿allowed￿in￿a￿retail￿service
center￿that￿has￿qualified￿and￿certified￿service￿technicians.￿These￿technicians￿must￿have
completed￿the￿ST1403b￿I01￿High￿Voltage￿Battery￿and￿Maintenance￿instructor￿led￿course￿and
successfully￿passed￿the￿hands￿on￿certification.
4.1.2.￿Installation￿location
The￿electrical￿machine￿electronics￿is￿installed￿in￿the￿rear￿of￿the￿I01,￿in￿an￿area￿separated￿from￿the
luggage￿compartment.
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