The thesis is based on investigating the feasibility of a superconducting cable in an aerospace electrical system. A superconducting cable as well as a superconducting motor would increase efficiency and decrease the weight of the electrical system. Background information on superconductivity is given, as is a review of current literature. The literature review investigates current superconducting materials, superconducting cables and superconducting AC losses. MgB2 is identified as a suitable material for the application. AC losses are then identified as a major potential problem in making superconducting cables in aerospace a viable option. Modelling and simulating the losses of the sheath and barrier of a superconducting cable under different operating conditions was completed. The model was simulated at different currents and frequencies, as well as using different sheath and barrier materials and configurations. The majority of the work was completed with the 2D finite-element software, FEMM, but later modelling work was accomplished using Flux2D which includes a specific superconducting module, allowing the superconducting material to be modelled more accurately. By simulating the model in FEMM the influence of the proximity effect in the sheath/barrier of multi-strand cables was investigated. It was found that although the proximity effect increased the losses; it was negligible compared to the decrease in losses gained from using a multi-strand wire. Using Flux2D enabled models of the superconducting core of the wire to be investigated as well as the sheath/barrier. From the simulation it was found that at critical current and 50Hz the superconductor was responsible for 99% of the AC losses. When the frequency was increased up to 800Hz for a 1.28mm Monel sheathed wire, however, the sheath/barrier losses were responsible for up to 20% of the losses.
|Date of Award||3 Jan 2015|
- The University of Manchester