Sensors - BMW I01 Product Information

I01￿High-voltage￿Components
9.￿Range￿Extender￿Electrical￿Machine
The￿electrical￿machine￿is￿designed￿for￿a￿large￿temperature￿range.￿The￿coolant￿can￿reach￿a￿temperature
of￿up￿to￿70 °C￿(158￿°F)￿at￿the￿input￿(supply)￿at￿a￿flow￿of￿six￿liters￿per￿minute.￿The￿temperature￿at
the￿input￿is￿time-restricted￿and￿can￿rise￿up￿to￿85 °C￿(185￿°F).￿And￿although￿the￿electrical￿machine
demonstrates￿less￿losses￿during￿energy￿conversion￿than￿a￿combustion￿engine,￿its￿housing￿can￿absorb
a￿temperature￿of￿up￿to￿100 °C￿(212￿°F).
The￿two￿connections￿for￿the￿coolant￿lines￿integrate￿the￿range￿extender￿electrical￿machine￿in￿the
cooling￿circuit￿of￿the￿electric￿motor.￿This￿is￿described￿in￿the￿chapter￿"Cooling￿of￿electric￿motor
components".￿The￿graphics￿in￿this￿chapter￿show￿the￿range￿extender￿electrical￿machine￿and￿the￿W20
engine￿without￿coating.￿In￿the￿production￿vehicle￿sometimes￿these￿components￿are￿still￿covered￿by￿a
foam￿part.￿This￿serves￿for￿the￿acoustic￿encapsulation￿of￿the￿range￿extender￿components￿and￿absorbs
noises￿which￿the￿customer￿may￿find￿irritating.
The￿housing￿of￿the￿range￿extender￿electrical￿machine￿is￿airtight￿and￿waterproof.￿A￿vent￿line￿is￿required
to￿prevent￿water￿(resulting￿from￿temperature￿changes￿and￿thus￿possible￿condensation￿of￿air￿humidity)
collecting￿inside￿the￿range￿extender￿electrical￿machine.
9.3.2.￿Sensors
Temperature￿sensor
In￿order￿to￿avoid￿damage￿to￿the￿components￿due￿to￿the￿high￿temperature,￿there￿is￿a￿temperature
sensor￿in￿the￿range￿extender￿electrical￿machine￿of￿the￿I01.￿The￿temperature￿sensor￿is￿a￿temperature-
dependent￿resistor￿and￿is￿located￿in￿the￿coils￿of￿the￿stator.￿The￿temperature￿of￿the￿rotor￿is￿not
measured￿directly,￿but￿can￿be￿determined￿from￿the￿measured￿values￿of￿the￿temperature￿sensors￿in
the￿stator.￿The￿signal￿is￿read￿in￿and￿evaluated￿analogously￿by￿the￿range￿extender￿electrical￿machine
electronics.
Rotor￿position￿sensor
The￿rotor￿position￿sensor￿cannot￿be￿replaced￿in￿Service￿
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