No abstract

Abstract-This paper presents innovative research towards the development of a 45 kW high speed switched reluctance drive as an alternative starter-generator for future aero-engines. To perform such a function the machine had to be designed with a very wide constant power-speed range. During enginestart/motoring mode, a peak torque demand of 54 Nm at 8 krpm was met, whilst in generating mode, 19.2-32 krpm, the machine was designed to deliver a constant power of 45 kW. The key enabling feature of the design lies in the novel rotor structure developed so as to allow for such a wide speed range. The results presented, are those measured during the initial testing phase and validate the system design and performance in the low-speed region with the machine operated in starting-mode. The measured machine power density is at 9.8 kW/ltr, whilst the global system efficiency is at 82%.

No abstract

This paper will describe a high speed motor-drive system for an aircraft starter-generator. A permanent magnet electrical machine is designed to have minimal rotor losses and a novel cooling system for the stator. An inner stator sleeve is adopted allow for a flooded stator whilst minimizing rotor windage loss. Different slot-pole combinations are compared in view of attaining an optimal combination that provides minimum losses whilst satisfying the electromagnetic, mechanical and thermal constrains. A three-level converter structure is adopted after a comparative study with a twolevel structure for different operating regimes. The performance of the complete drive system will be presented through simulation results.

No abstract