Technical Paper
Alternator Whining Noise-A Sound Quality Concern in Passenger Car
2011-01-19
2011-26-0018
Quality of the sound is one of the major parameter for the occupants comfort. The vehicle noise can be broadly classified into airborne and structure borne noise contributed by numerous aggregates present in vehicle. Among different vehicle aggregates the alternator, which is an important component in vehicle electrical architecture, can be considered as a major source of airborne noise. Generally, the alternator noise is combination of mechanical, aerodynamic, and electromagnetic sources. The ratio of these sources in the overall noise varies with speed and loading pattern. The mechanical and aerodynamic noise normally depends on speed while the electromagnetic noise variation is load dependent. Alternator whining is an irritant perception of the sound quality due to electromagnetic noise. When the alternator is loaded with electrical loads (like head lamp, tail lamp, wiper and HVAC) the sound level increases further.