Optimization and Analysis of a High Power Density and Fault Tolerant Starter–Generator for Aircraft Application

Bo Wang,Gaurang Vakil,Ye Liu,Chris Gerada,Zhuoran Zhang,Tao Yang

doi:10.3390/en14010113

Abstract

Permanent magnet synchronous machines provide many dramatic electromagnetic performances such as high efficiency and high power density, which make them more competitive in aircraft electrification, whereas, designing a permanent magnet starter–generator (PMSG), with given consideration to fault tolerance (FT), is a significant challenge and requires great effort. In this paper, a comprehensive FT PMSG design process is proposed which is applied to power systems of turboprops. Firstly, potential slot/pole combinations were selected based on winding factor, harmonic losses and manufacture issues. Then, pursuing high power density, a multiple objective optimization process was carried out to comprehensively rank performances. To meet a fault tolerance target, electrical, magnetic and thermal isolation topologies were investigated and compared, among which 18 slot/12 pole with dual three-phase was selected as the optimal one, with a power density of 7.9 kW/kg. Finally, a finite element analysis verified the performance in normal and post-fault scenarios. The candidate machine has merits concerning high power density and post-fault performance.

Highlights

IntroductionReliability and integrated technologies are core pillars of the evolution of aviation
The aviation industry recognizes the need to address the global challenge of climate change and has taken up a range of ambitious targets to mitigate CO2 emissions in air transportation [1]
The main objective of this paper is to present a design and trade-off process for a surface mounted permanent magnet starter–generator (PMSG) to meet the requirements of high power density and fault tolerance

Summary

Introduction

Reliability and integrated technologies are core pillars of the evolution of aviation. Integrated starter–generators (SGs), which provide the functions of engine acceleration and electricity supply, are the main power source for onboard equipment. The three-stage synchronous starter–generator is a mature candidate for current electrical power systems; it consist of a pre-exciter, a main exciter and a main generator [2]. This architecture exhibits the remarkable benefits of reliability and inherent safety because of its de-excitation ability. Concerning the embedded power electronics on the rotating rotor, the configuration of the rotor is too complex for operation at high speed, which could result in mechanical failure. Different control strategies in motoring and generation modes increase the system’s complexity

Objectives

Methods

Results

Conclusion