Electrical machine technologies for an electric tail rotor drive

Abstract

This paper present findings from an EU JTI Clean Sky funded program investigating the feasibility of driving electrically the tail rotor of a helicopter. Since the tail rotor drive is a safety critical component a major emphasis has been on the faulted behaviour of the electrical system and the realisation of a high level of integrity. Designs of two candidate fault tolerant axial-flux and radial-flux electric tail rotor motors are presented and compared. The approach adopted to model the thermal behaviour of the designs during normal and faulted operation is outlined and the impact of the aircraft mission duty on the accrued motor life described. The discussion is backed with findings from full size prototypes of the electric tail rotor motor designs.