Small-Signal Modeling and Stability Specification of a Hybrid Propulsion System for Aircrafts

This work utilizes the small-signal impedance-based stability analysis method to develop stability assessment criteria for a single-aisle turboelectric aircraft with aft boundary-layer propulsion (STARC-ABL) system. The impedance-based stability analysis method outperforms other stability analysis methods because it does not require detailed information of individual components for system integration, therefore, a system integrator can just require the vendors to make the individual components meet the impedance specifications to ensure whole system stability. This thesis presents models of a generator, motor, housekeeping loads, and battery all with power electronics interface which form an onboard electrical system and analyzes the relationship between the impedance shape of each component and their physical design and control loop design. Based on the developed small-signal model of the turbine-generator-rectifier subsystem and load subsystem, this thesis analyzes the impact of electromechanical dynamics of the turbofan passed through the generator on the dc distribution system, concluding that the rectifier can mitigate the impact. Finally, to ensure the studied system stable operation during the whole flying profile, the thesis provides impedance specifications of the dc distribution system and verifies the specifications with several cases in time-domain simulations.

Name thesis:degree_name

M.S.

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Power Electronics

Department dc:contributor.department

Electrical and Computer Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2021

Author dc:creator

• Lin, Qing

Chair dc:contributor.committeechair

• Burgos, Rolando

Committee members dc:contributor.committeemember

• Wen, Bo
• Spakovsky, Michael R. von
• De La Ree, Jamie

• Small-signal modeling
• Impedance-based stability analysis
• Electric machine
• Power electronics converter
• Electric aircraft propulsion
• DC distribution system

Statement dc:rights

• Attribution-NonCommercial-NoDerivatives 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc-nd/4.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/103515

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/103515