Miniaturisation of electrical machines

Abstract

Purpose – Approaches for a miniaturisation of electrical machines that are based on an electromagnetic principle have to overcome numerous challenges. Some of these are only a result of the rules of growth (or shrinkage), some are a result of the micro technological fabrication processes. This paper aims to give an overview of the current state of the art including various examples of linear and rotating micro actuators that have been realised. Design/methodology/approach – The paper presents details of further miniaturisation by using thin film technology for depositing and structuring soft magnetic and hard magnetic material as well as copper for conductors and insulation. Findings – There are numerous limitations for the miniaturisation with respect to material properties, friction/guidance, etc. and this paper illustrates ways to overcome these limitations. Originality/value – The paper presents a compact overview on the achievements gained in 12 years of research within a collaborative research centre of the German DFG. © 2011, Emerald Group Publishing Limited