Advanced electrical machines and actuators for new and emerging applications

There is a continual demand for advanced electrical machines and drives for wide-ranging applications in all market sectors. The motivation for their development varies considerably. However, common objectives are to improve efficiency, and, thereby, to conserve energy and reduce environmental pollution, increase power density, enhance functionality, and improve reliability and maintainability, whilst the adoption of ´more-electric´ technologies is also being driven by legislation, consumer expectations regarding performance and more fierce competition in the market place. The paper reviews recent developments in electrical machines and actuators, facilitated by advances in magnetic materials, semiconductor switching devices, power electronic converters and control systems, by briefly describing some of the research activities which are being undertaken at the University of Sheffield, with particular emphasis on applications in the automotive and aerospace sectors. It also highlights the fact that there remains considerable scope for design innovation. Many of the applications pose particularly severe challenges in terms of the thermal operating environment, the rotational speed and/or space envelope constraints, for example, whilst others are particularly challenging in terms of being highly cost-sensitive or safety critical.