By Prof. Patrick McCluskey
The substitution of electric motors for traditional combustion engines in vehicle drive systems is a major component of sustainable development. Compared to traditional combustion engines, electric motors have significantly higher efficiency coupled with reduced carbon and noise emissions. While these advantages have been exploited by the automotive industry for more than a decade in hybrid and electric cars, they are just now being investigated for use in large passenger aircraft. Aircraft applications, however, have their own unique challenges, including achieving > 1 MW levels of power at minimal weight. Such high power densities (>25 kW/kg), require the high efficiency achieved by integrating the power and control electronics with the motor in a small enclosure. An advanced thermal management system is needed to cool such a system, ensuring the temperatures of all components remain within safe limit under all conditions. Furthermore, the cooling system itself should be efficient (i.e. high COP), lightweight, and reliable.