Electrical Machine Development : a study of four different machine types from Swedish perspective

Sammanfattning: Development and manufacturing of rotating electrical machines have been essential for the Swedish society and industry for more than a century. The dominating manufacturer has been Asea/ABB, even if a more diversified structure has emerged in recent years. The thesis deals primarily with Asea/ABB’s development of four kinds of electrical machines, although reflected against a wider national and international background. The purpose of the research has been to study the development of these machines and the related industrial processes, focusing on factors with a major influence on the development.The thesis contains introductory chapters presenting the research, the public importance of electrical machines, their initial history, as well as a technical introduction of the machines and the development process. The main chapters start with standard induction motors which are manufactured in large numbers and can be seen as a commodity with little product differentiation. The development focus has been on rational production and increased use for frequency controlled variable speed drives. Large directly water-cooled turbogenerators were developed for nuclear power plants, in the 1970’s, and created initially many difficulties. Advanced technologies and strategic matters have been strongly interlinked in this development, which is described comprehensively in the thesis. Electrical machines for automotive drivelines have, in recent years, been subject to intensive international development and several new concepts have been introduced. The thesis analyzes the Swedish attempts that have been technically satisfactory but have not led to commercial products. ABB launched synchronous machines for very high voltages as a revolutionary product ten years ago, but without commercial success. This controversial development and the difficult business situation are subject for discussion in the fourth main chapterThe study presents conclusions, concerning the development, individually for each machine type, but also comparisons based on divisions in large and small machines and in mature and new technologies. A common result is that the development, in retrospect, has been more successful from technical point of view than from commercial, independently whether the development has been market or technology driven. An important contribution of the thesis is that it presents the first comprehensive Swedish study of electrical machine development and which factors have been most influential. The thesis ends with a discussion of future prospects for the Swedish electrical machine industry and the possibilities and threats it is facing.