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The cubic form of SiC (βor 3C-) compared to the hexagonal α-SiC polytypes, primarily 4H-and 6H-SiC, has lower growth cost and can be grown heteroepitaxially in large area Silicon (Si) wafers which makes it of special interest. This in conjunction with the recently reported growth of improved quality 3C-SiC, make the development of devices an imminent objective. However, the readiness of models that accurately predict the material characteristics, properties and performance is an imperative requirement for attaining the design and optimization of functional devices. The purpose of this study is to provide and validate a comprehensive set of models alongside with their parameters for bulk 3C-SiC. The validation process revealed that the proposed models are in a very good agreement to experimental data and confidence ranges were identified. This is the first piece of work achieving that for 3C-SiC. Considerably, it constitutes the necessary step for Finite Element Method (FEM) simulations and Technology Computer Aided Design (TCAD).

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This work offers a reliable solution to the detection of broken rotor bars in induction machines with a novel methodology, which is based on the fact that the fault related harmonics will have oscillating amplitudes due to the speed ripple effect. The method consists of two main steps: Initially, a timefrequency transformation is used and the focus is given on the steady-state regime; thereupon, the fault related frequencies are handled as periodical signals over time and the classical Fast Fourier Transform is used for the evaluation of their own spectral content. This leads to the discrimination of sub-components related to the fault and evaluation of their amplitudes. The versatility of the proposed method relies on the fact that it reveals the aforementioned signatures to detect the fault, regardless of the spatial location of the broken rotor bars. Extensive finite element simulations on a 1.1MW induction motor and experimental testing on a 1.1kW induction motor lead to the conclusion that, the method can be generalized on any type of induction motor independently from the size, power, number of poles and rotor slot numbers.

This document is the author's post-print version, incorporating any revisions agreed during the peer-review process. Some differences between the published version and this version may remain and you are advised to consult the published version if you wish to cite from it.

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