Electrothermal design exploration of electric machines using hollow conductors

This thesis presents preliminary electromagnetic and thermal considerations for hollow conductors filled with coolants to be used as new-age winding alternatives for mega-watt class power-dense electric machines for the next generation of electrified aircraft. First, a Double Layer Fractional Slot Concentrated Wound machine is designed as a baseline motor, due to its advantages presented in the reduction of the end-winding losses. Next, to study the impact of the hollow conductors and quantify the increase in power density, an updated machine is designed, within the same motor housing. To demonstrate the cooling capabilities of the hollow conductors, thermal analysis is performed on both the machine models and the reduction in operating temperature is quantified. This thesis first introduces the operational principle of concentrated fractional slot wound machines. Then, the design process of the two machine models is explored, including a parameterized machine model that aids in easily viewing geometry followed by in-depth finite element analysis. Next, modeling strategies of the hollow conductors and their impact on the thermal analysis are introduced. This is followed by revising the electromagnetic models of the winding to obtain accurate ohmic loss models of the windings, which are fed into the thermal winding models to predict the temperature rise in the winding hotspot region. Finally, the rise in temperature of the windings and the increase in power density from employing hollow conductors is classified.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Electrical & Computer Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Bajaj, Parag

Contributors dc:contributor

• Haran, Kiruba

• Thermal Management Systems
• Hollow Conductors
• Electro-thermal Design

Statement dc:rights

• Copyright 2024 Parag Bajaj

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/124724

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F124724