Skip to main content

Research Repository

See what's under the surface

Advanced Search

Insulation systems for electrical machines: Reliability MUST become a main design objective

Galea, Michael; Giangrande, Paolo; Madonna, Vincenzo; Buticchi, Giampaolo


Michael Galea

Paolo Giangrande

Vincenzo Madonna

Giampaolo Buticchi


As the world of transport keeps moving towards 'heavier' electrification, the main design objectives in terms of power density and efficiency of system components, are resulting ever-more important. On the other hand, transport applications are also very safety critical. The 'extra' stresses being seen by important components, such as electrical machines and their insulation systems, in order to achieve the required performances, are therefore inducing more accelerated degradation in terms of the components' lifetime and reliability. In general, lifetime consumption and degradation of components, such as for insulation systems of electrical machines, is still assessed through 'statistical' methods (i.e. recording the number of imposed cycles until failure of a built prototype). This is of course a very time-consuming and expensive process. In application fields such as automotive and aerospace, these can be the major bottleneck in terms of the development timeline of an electrical product, especially for certification. This article therefore argues for the development of new processes, based on comprehensive, physics of failure methodologies, that will enable the electrical machine designer to make reliability considerations for insulation systems of electrical machines, a main design objective, right from the very start of the design process. This paper investigates and describes how this advanced philosophy will allow manufacturers to design insulation systems without relying on the outdated, traditional 'safety factors' and over-engineering philosophies.

Journal Article Type Article
Journal IEEE Industrial Electronics Magazine
Print ISSN 1932-4529
Electronic ISSN 1932-4529
Publisher Institute of Electrical and Electronics Engineers
Peer Reviewed Peer Reviewed
APA6 Citation Galea, M., Giangrande, P., Madonna, V., & Buticchi, G. (in press). Insulation systems for electrical machines: Reliability MUST become a main design objective. IEEE Industrial Electronics Magazine,
Keywords Index Terms -Electrical machines; Insulation systems; Lifetime degradation; Reliability; Physics of Failure