Introducing a new theory for electrical machines Air-gap magnetic field modulation phenomena have been widely observed in electrical machines. This book serves as the first English-language overview of these phenomena, as well as developing systematically for the first time a general theory by which to understand and research them. This theory not only serves to unify analysis of disparate electrical machines, from convention DC machines, induction machines, and synchronous machines, but also paves the way towards the creation of new electrical machine topologies. General Airgap Field Modulation Theory for Electrical Machines includes both overviews of key concepts in electrical machine engineering and in-depth specialized analysis of the novel theory itself. It works through the applications of the developed theory before proceeding to both qualitative analysis of the theory's operating principles and quantitative analysis of its parameters. In General Airgap Field Modulation Theory readers will also find: * The collective experience of four award-winning authors with long records of international scholarship on this subject * Three separate chapters covering the principal applications of the theory, with detailed examples * Discussion of potential innovations made possible by this theory General Airgap Field Modulation Theory is an essential introduction to this theory for postgraduates, researchers, and electrical engineers.