BMW I01, Информация о продукте

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I01�High-voltage�Components
4.�Electrical�Machine�Electronics
63
Operating�principle�of�the�DC/DC�converter
Index Explanation
1 Voltage�of�the�high-voltage�electrical�system,�about�250 V�to�about�410 V
2 Down�conversion
3 DC/DC�converter�in�the�EME
4 Voltage�of�the�low-voltage�vehicle�electrical�system,�about�14 V
The�technology�of�the�DC/DC�converter�in�the�I01�would�also�enable�the�operating�mode�"Boost
mode",�such�as�the�DC/DC�converter�in�the�F04.�However,�this�operating�mode�is�not�used�in�the�I01.
Charging�of�the�high-voltage�battery�of�the�I01�is�not�possible�using�energy�from�the�12 V�vehicle
electrical�system.
The�last�operating�mode�of�the�DC/DC�converter�is�assumed�during�(regular�or�quick)�shutdown�of�the
high-voltage�system.�For�the�shutdown�of�the�high-voltage�system�the�system�must�be�discharged
to�a�safe�voltage�less�than�60 V�within�a�specified�time.�The�DC/DC�converter�has�a�discharge�circuit
for�the�link�capacitors.�First�of�all,�these�try�to�transmit�the�energy�stored�in�the�link�capacitors�to
the�low-voltage�vehicle�electrical�system.�If�this�does�not�lead�to�a�sufficiently�quick�reduction�of�the
voltage,�the�discharging�is�effected�via�an�active�resistor.�This�way�the�high-voltage�electrical�system
is�discharged�in�less�than�5�seconds.�For�safety�reasons�there�is�also�a�so-called�passive�discharge