Design and initial testing of an outer rotating segmented rotor switched reluctance machine for an aero-engine shaft-line-embedded starter/generator

This paper describes research aimed at producing a shaft-line-embedded starter/generator for an aircraft gas turbine. This machine needs to run in a very high ambient temperature of around 350 degC, whilst at the same time having a very high specific output. A review is made of possible designs that highlights potential mechanical and thermal problems and which eliminates the use of some machine topologies. The paper suggests that an outer rotating segmented rotor switched reluctance motor topology could satisfy all the thermal, mechanical and electromagnetic requirements. An initial prototype has been constructed to allow verification of the design and the design methods used. Preliminary results indicate that the performance, size and thermal requirements can be achieved using a fully developed version of this machine

I Introduction

The aerospace industry has realized that continual improvement in the services offered to the consumer, and future environmental targets can only be achieved through global re-optimisation of both the aircraft and the engine [1]. This has initiated the More Electric Engine (MEE) and More Electric Aircraft (MEA) programs [1], [2].