Close

Valeo

EG efficiency generator

An alternator, connected to the crankshaft by a belt, transforms mechanical energy into electrical in order to power the operating systems of a motor vehicle. However, it adds a substantial load and drain on power production, and is not entirely efficient; losing about 30% of power in the transition. Ten percent, or one third of the total loss, is attributable to the rectifying bridge. The purpose of the rectifying bridge is to convert alternating into direct current. Until now diodes have been used for this purpose.

Valeo has substituted MOSFETs (metal oxide semiconductor field effect transistors) for diodes, and solved the problems of location in a hostile environment. MOSFETs lose essentially no power in transition, improving alternator efficiency by ten percent, and improving fuel efficiency by 0.7 mpg. Idle output has been increased by 15 amps, allowing for a downsized design, or increased power supply with no increase in alternator size. This the first time that microelectronics have been used in motor vehicle alternator construction. Audi A6 is the first customer.