A Study of Brushless Doubly-Fed (Induction) Machines CONTRIBUTIONS IN MACHINE ANALYSIS, DESIGN AND CONTROL

To God, Ruth and my parents. I will lift my eyes to the mountains; From where shall my help come? My help comes from the LORD, Who made heaven and earth. Psalm 121 The Brushless Doubly-Fed Machine (BDFM) shows commercial promise as a variable speed drive or generator. However, for this promise to be realised the design of the machine must be improved be-yond that proposed to date. This dissertation contributes towards this goal through machine analysis, design and control. A generalised framework is developed for a coherent and rigorous derivation of models for a wide class of BDFMs, of which machines with `nested-loop ' design rotors are a subset. This framework is used to derive coupled circuit, d-q axis, sequence components and then equivalent circuit models for the class of machines. Proofs are given for all derivations, exploiting the circulant propertie