Electrical Signature Analysis Applications for Non-Intrusive Automotive Alternator Diagnostics

Automotive alternators are designed to supply power for automobile engine ignition systems as well as charge the storage battery. This product is used in a large market where consumers are concerned with acoustic noise and vibration that comes from the unit, as well as overall quality and dependability. Alternators and generators in general are used in industries other than automotive, such as transportation and airline industries and in military applications. Their manufacturers are interested in pursuing state-of-the-art methods to achieve higher quality and reduced costs. Preliminary investigations of non-intrusive diagnostic techniques utilizing the inherent voltage signals of alternators have been performed with promising results. These techniques are based on time and frequency domain analyses of specially conditioned signals taken from several alternators under various test conditions. This paper discusses investigations that show correlations of the alternator output voltage to airborne noise production. In addition, these signals provide insight into internal magnetic characteristics that relate to design and/or assembly problems. This article is from Technology Showcase: Integrated Monitoring, Diagnostics and Failure Prevention. Proceedings of a Joint Conference, Mobile, Alabama, April 22-26, 1996, AD-A325 558, p1-10.