BMW I01 Product Information page 23

I01￿High-voltage￿Components
3.￿Electric￿Motor
Principal￿structure￿of￿the￿synchronous￿machine
Index
A
B
1
2
3
4
To￿improve￿the￿technical￿data￿the￿structure,￿primarily￿of￿the￿rotor,￿was￿modified￿and￿optimized.￿The
rotor￿has￿a￿new￿arrangement￿of￿the￿permanent￿magnets￿and￿a￿stack￿of￿sheets￿which￿has￿a￿positive
influence￿on￿the￿characteristic￿of￿the￿magnetic￿field￿lines.￿On￿the￿one￿hand,￿this￿improves￿the￿torque.
On￿the￿other￿hand,￿there￿are￿lower￿current￿levels￿in￿the￿stator￿coils,￿whereby￿the￿efficiency￿is￿increased
in￿comparison￿to￿a￿conventional￿synchronous￿machine.
The￿impressive￿performance￿data￿are￿summarized￿in￿the￿following￿table.
Nominal￿voltage
Nominal￿current
Maximum￿peak￿output
Maximum￿continuous￿output
Maximum￿torque
Maximum￿engine￿speed
Weight
The￿maximum￿power￿of￿125 kW￿can￿only￿be￿made￿available￿for￿a￿maximum￿duration￿of￿30￿s.
Otherwise,￿the￿components￿of￿the￿drive￿train￿would￿be￿damaged￿through￿overheating￿–￿this￿affects￿not
only￿the￿electrical￿machine,￿but￿also￿the￿high-voltage￿battery￿and￿the￿electrical￿machine￿electronics.
The￿maximum￿power￿applies￿for￿the￿motor￿operation￿–￿in￿theory￿it￿could￿also￿be￿used￿in￿the￿alternator
Explanation
Conventional￿synchronous￿machine
Synchronous￿machine￿in￿the￿I01
Stator
Stack￿of￿sheets,￿rotor
South￿pole￿of￿a￿permanent￿magnet
North￿pole￿of￿a￿permanent￿magnet
360 V
400 A
125 kW/170 bhp
about￿75 kW
250 Nm/184￿lb-ft
about￿11,400 1￿min.
about￿49 kg
Actual￿value
for￿a￿maximum￿duration￿of￿30 s
continuous
in￿the￿engine￿speed￿range
0 – 5,000 rpm.
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