BMW I01 Product Information page 71

I01￿High-voltage￿Components
4.￿Electrical￿Machine￿Electronics
The￿temperature￿of￿the￿DC/DC￿converter￿is￿measured￿using￿a￿temperature￿sensor￿and￿monitored
by￿the￿EME￿control￿unit.￿If￿the￿temperature￿exceeds￿the￿permissible￿range￿despite￿cooling￿using￿the
coolant,￿the￿EME￿control￿unit￿reduces￿the￿power￿of￿the￿DC/DC￿converter￿to￿protect￿the￿components.
Power￿electronics￿for￿activation￿of￿the￿electrical￿machine
The￿power￿electronics￿for￿the￿activation￿of￿the￿electrical￿machine￿are￿mainly￿made￿up￿of￿the
bidirectional￿DC/AC￿converter.￿It￿is￿a￿pulse￿converter￿with￿a￿two-pin￿DC￿voltage￿connection￿and￿a￿3-
phase￿AC￿voltage￿connection.￿This￿DC/AC￿converter￿can￿work￿as￿an￿inverter￿and￿conduct￿electrical
energy￿from￿the￿high-voltage￿battery￿to￿the￿electrical￿machine￿when￿it￿should￿work￿as￿an￿engine.
However,￿it￿can￿also￿work￿as￿a￿rectifier￿and￿transfers￿electrical￿energy￿from￿the￿electrical￿machine￿to
the￿high-voltage￿battery.￿This￿operating￿mode￿occurs￿during￿brake￿energy￿regeneration￿in￿which￿the
electrical￿machine￿works￿as￿an￿alternator￿and￿"generates"￿electrical￿energy.
Operating￿modes￿of￿the￿bidirectional￿DC/AC￿converter
65