This chapter shows that chemical and wear analysis have been demonstrated to be effective global monitoring techniques for electrical machines which can produce narrow bandwidth (<1 Hz) signals. Chemical degradation of insulating materials and lubricants are detectable and can give bulk indications of the condition of an electrical machine. This is particularly important when it is considered how central insulation and lubrication integrity are to the long-term life of a machine. However, the detectability criteria for these techniques are difficult, the chemical analysis processes involved are complex and expensive, and the quantity of data generated by chemical analysis currently confine their application to only the largest machines.

Inspec keywords: monitoring; electric machines; machine insulation; insulating materials

Other keywords: interference-free measurements; electrical machines; wear analysis; chemical degradation; chemical monitoring; insulating materials; bandwidth signals; chemical analysis processes; coaxial electrical circuits; effective global monitoring techniques

Subjects: a.c. machines