This disruptive change in aircraft design and operation will only come about if the power per weight and volume of electrical machines can be reduced substantially. As it will not be possible to deliver this through incremental changes and radical novel approaches to electrical machine manufacture and design are needed. High efficiency is also an essential requirement, if weight savings are not to be overshadowed by the additional fuel load needed to supply the power conversion losses. We are addressing the challenges of light weighting electrical machines through multi-discipline research, bringing together internationally recognised expertise in composite materials, and electrical machine loss and thermal analysis, with advanced composite and additive manufacture capabilities and state-of test and measurement facilities. 

Electric Propulsion of a Helicopter Tail Rotor 

Supported through EU JTI Clean Sky funding the group supplied the electrical machine design to this program, which demonstrated, at full scale, the direct-drive, air-cooled electrical propulsion of the tail rotor of a medium size, twin-engined helicopter.  Alongside the design development, we oversaw the prototyping of the propulsion motor and has estabilished a unique test facility in our laboratories for fault-tolerant electric drives, rated up to 1 MVA.   

Magnetic permeable rotor containment for high-speed electrical machine

When operated at high surface speeds the field excitation system on the rotor needs to be contained; this is usually undertaken using a high strength steel or carbon composite sleeve.  The disadvantage with these containment technologies is that they introduce an additional magnetic airgap which degrades the electromagnetic performance of the electrical machine.  A range of high strength tailored materials with tailored magnetic properties are being developed and have been proven to provide superior performances compared to the conventional solutions.