Power regulation system for electric motor driving centrifugal blower for heating or ventilation system in motor vehicle

摘要

The power of an electric motor (16) that is used to drive the turbine rotor (14) of a centrifugal blower is controlled by an electronic circuit having power transistors that have to be cooled. The transistors (48) are mounted on a heat sink of aluminium (42) positioned at the rear of the motor. The turbine rotates within an involute-shaped casing (22) and this has a side channel (10) with a passage (66) leading to the region where the power transistors and heat sink are located. The air is directed across the heat sink and this has a series of fins to dissipate the heat.