The Field Orientation Principle was fIrst formulated by Haase, in 1968, and Blaschke, in 1970. At that time, their ideas seemed impractical because of the insufficient means of implementation. However, in the early eighties, technological advances in static power converters and microprocessor-based control systems made the high-performance a. c. drive systems fully feasible. Since then, hundreds of papers dealing with various aspects of the Field Orientation Principle have appeared every year in the technical literature, and numerous commercial high-performance a. c. drives based on this principle have been developed. The term "vector control" is often used with regard to these systems. Today, it seems certain that almost all d. c. industrial drives will be ousted in the foreseeable future, to be, in major part, superseded by a. c. drive systems with vector controlled induction motors. This transition has already been taking place in industries of developed countries. Vector controlled a. c. drives have been proven capable of even better dynamic performance than d. c. drive systems, because of higher allowable speeds and shorter time constants of a. c. motors. It should be mentioned that the Field Orientation Principle can be used in control not only of induction (asynchronous) motors, but of all kinds of synchronous motors as well. Vector controlled drive systems with the so­ called brushless d. c. motors have found many applications in high­ performance drive systems, such as machine tools and industrial robots.

Focused on the appreciation of anthropology, the new edition of "Cultural Anthropology" offers an up-to-date holistic introduction to cultural anthropology. Key themes of appreciating the experiences students bring to the classroom, appreciating cultural diversity, and appreciating the field of anthropology are showcased throughout the text. In this edition, Understanding Ourselves chapter openers and Through the Eyes of Others boxes show how anthropology helps us understand ourselves. New Appreciating Diversity boxes focus on the various forms of human biological and cultural diversity. Appreciating Anthropology boxes are also new to the text and focus on the value and usefulness of anthropological research and approaches.

Product Description: This handbook deals with the asynchronous machine in its close environment. It was born from a reflection on this electromagnetic converter whose integration in industrial environments takes a wide part. Previously this type of motor operated at fixed speed, from now on it has been integrated more and more in processes at variable speed...read more

Product Description: This book is a comprehensive reference source for practicing engineers and students specializing in electric power engineering and industrial electronics. It will illustrate the state of the art in induction motors. Beginning with characteristics and basic dynamic models of induction motors, and progressing to low- and high- performance drive systems...read more (view table of contents, read Amazon.com's description)