Introduction - BMW I01 Product Information

I01￿High-voltage￿Components
9.￿Range￿Extender￿Electrical￿Machine
9.1.￿Introduction
The￿high-voltage￿components￿examined￿up￿to￿now￿pave￿the￿way￿for￿a￿pure￿electric￿driving￿of￿the
I01.￿The￿electrical￿machine￿receives￿the￿energy￿required￿for￿the￿electric￿motor￿from￿the￿high-voltage
battery.￿The￿EME￿converts￿the￿direct￿current￿voltage￿from￿the￿high-voltage￿battery￿into￿3-phase￿AC
voltage.
The￿I01￿with￿a￿pure￿electric￿driving￿is￿designed￿so￿that￿a￿distance￿of￿about￿150 km￿/￿93￿mi￿(115￿mi
using￿efficiency￿mode)￿can￿be￿covered￿before￿the￿high-voltage￿battery￿must￿be￿charged￿up￿again.￿The
high-voltage￿battery￿can￿also￿be￿charged￿at￿an￿earlier￿stage.
A￿I01￿which￿is￿equipped￿with￿a￿range￿extender￿can￿cover￿a￿distance￿of￿about￿300 km￿/￿186￿mi￿(200
mi￿using￿efficiency￿mode)￿before￿the￿high-voltage￿battery￿has￿to￿be￿charged￿or￿the￿tank￿has￿to￿be
refuelled.￿This￿means￿a￿I01￿with￿range￿extender￿offers￿double￿the￿range￿in￿comparison￿to￿a￿I01￿with￿a
purely￿electric￿motor.
Also￿in￿the￿I01￿with￿range￿extender￿the￿electric￿motor￿with￿energy￿from￿the￿high-voltage￿battery￿is￿used
as￿a￿primary￿drive￿type.￿The￿range￿extender￿system￿is￿only￿activated￿when￿the￿state￿of￿charge￿of￿the
high-voltage￿battery￿falls￿below￿a￿certain￿value.
The￿range￿extender￿system￿consists￿of￿the￿following￿components:
• W20￿Combustion￿engine
• Range￿extender￿electrical￿machine
• Range￿Extender￿Electrical￿Machine￿Electronics
• Range￿Extender￿Digital￿Engine￿Electronics.
The￿W20￿combustion￿engine￿is￿a￿2-cylinder￿engine.￿It￿is￿a￿small,￿very￿smooth-running￿and￿quiet
gasoline￿engine,￿which￿is￿connected￿mechanically￿to￿the￿range￿extender￿electrical￿machine￿via￿a
geared￿shaft.￿At￿a￿low￿state￿of￿charge￿of￿the￿high-voltage￿battery￿the￿W20￿engine￿is￿started￿using￿the
range￿extender￿electrical￿machine.￿In￿this￿case￿the￿range￿extender￿electrical￿machine￿works￿in￿engine
mode.￿The￿electrical￿energy￿for￿starting￿the￿W20￿engine￿comes￿from￿the￿high-voltage￿battery.￿As￿soon
as￿the￿W20￿has￿been￿started,￿the￿range￿extender￿electrical￿machine￿changes￿from￿engine￿to￿alternator
mode￿and￿generates￿electrical￿energy￿which￿is￿used￿for￿the￿electric￿motor￿of￿the￿vehicle￿via￿the￿(main)
electrical￿machine.￿The￿W20￿engine￿is￿not￿connected￿mechanically￿to￿the￿sprockets.￿The￿mechanical
energy￿of￿the￿W20￿engine￿is￿converted￿by￿the￿range￿extender￿electrical￿machine￿solely￿into￿electrical
energy.￿The￿(main)￿electrical￿machine￿uses￿this￿electrical￿energy￿and￿converts￿it￿to￿mechanical￿energy
to￿drive￿the￿rear￿wheels.￿The￿layout￿of￿these￿components￿corresponds￿to￿a￿serial￿hybrid￿car.
In￿this￿chapter￿the￿range￿extender￿electrical￿machine￿is￿described￿and￿in￿the￿next￿chapter￿details￿are
provided￿on￿the￿range￿extender￿electrical￿machine￿electronics.
The￿W20￿engine￿and￿the￿engine￿control￿of￿the￿range￿extender￿digital￿engine￿electronics￿are￿described
in￿the￿product￿information￿bulletin￿"W20￿Engine".
9.2.￿Technical￿data
The￿performance￿data￿of￿the￿range￿extender￿electrical￿machine￿is￿summarized￿in￿the￿following￿table:
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