Design, Build & Test of an HTS Machine A.C. Loss Measurement Platform: Aircraft Applications

Abstract

Superconductors are entering into an exciting period since their discovery in the early 1900s. Electrification is becoming more economically feasible in all modes of applications where harmful gas emitting technologies are used. While it is true that superconductors at their current technology level are unlikely to rival copper based technologies for low and high power applications, in environments where specific weights and power density are a priority they have already been proven to be more efficient and cost effective. Furthermore, since the late 1900s when superconducting machine projects were launched, much progress has been made towards making the technology technically and economically feasible.

The work contained in this thesis focusses on pushing superconductors towards scalable commercialisation by focussing on a crucial limiting factor, namely A.C. losses. In an A.C. operating environment, superconductors produce heat which must be dissipated to maintain superconductivity. On the other hand, virtually zero loss is measured in the D.C. operation. In rotating electrical machines the A.C. environment is unavoidable and we must understand and mitigate this characteristic to lower the cryogenic system cost, improve efficiency and realise the ambition of many in the research field to see widespread adoption of superconductors in transportation.

To this end, the following items of original, new work in this thesis include:

1. Design, build and test of a novel A.C. loss measurement platform integrating a motor environment.
2. Measurement of the A.C. losses produced within a live operating machine.
3. Characterisation of cutting edge A.C. loss reduction techniques using the newly developed measurement rig.
4. Development of a baseline target performance required from superconducting technology for electrical aircraft propulsion feasibility.

Date of Award	19 Jun 2019
Original language	English
Awarding Institution	University of Bath
Supervisor	Francis Robinson (Supervisor) & John Eastham (Supervisor)