The Field Orientation Principle (FOP) constitutes a fundamental concept behind the modern technology of high-performance, vector-controlled drive systems with AC motors. The recent intense interest in these systems has been spawned by the widespread transition from DC to AC drives in industry. Induction motors, industry's traditional workhorses, are particularly well suited for FOP-based vector control. The Field Orientation Principle in Control of Induction Motors presents the FOP in a simple, easy-to-understand framework based on the space-vector dynamic model of the induction machine. Relationships between the classic phasor equivalent circuits of the motor and their vector counterparts are highlighted. A step-by-step derivation of dynamic equations of the motor provides a formal background for explanation of the basic approaches to vector control. In addition, the author presents scalar control methods for low-performance drives as an intermediate stage between uncontrolled and high-performance drives. The reader will also find a full chapter devoted to power inverters, which constitute an important component of adjustable speed AC drive systems, and a review of associated issues such as observers of motor variables, parameter estimation, adaptive tuning, and principles of the position and speed control of field-oriented induction motors. With a wealth of numerical examples and computer simulations illustrating the ideas and techniques discussed and an extensive bibliography, The Field Orientation Principle in Control of Induction Motors is a practical resource and valuable reference for researchers and students interested in motor control, power and industrial electronics, and control theory.

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.

This book provides the most important steps and concerns in the design of estimation and control algorithms for induction motors. A single notation and modern nonlinear control terminology is used to make the book accessible, although a more theoretical control viewpoint is also given. Focusing on the induction motor with, the concepts of stability and nonlinear control theory given in appendices, this book covers: speed sensorless control; design of adaptive observers and parameter estimators; a discussion of nonlinear adaptive controls containing parameter estimation algorithms; and comparative simulations of different control algorithms. The book sets out basic assumptions, structural properties, modelling, state feedback control and estimation algorithms, then moves to more complex output feedback control algorithms, based on stator current measurements, and modelling for speed sensorless control. The induction motor exhibits many typical and unavoidable nonlinear features.

This book provides a thorough approach for mastering the behavior and operation of induction motors, an essential device in the modern industrial world. Its way of presentation renders this book suitable for selfteaching by students, engineers, and researchers in the field of electrical engineering. It covers the modern theory of induction motor applications and control methods. The transient analysis of both three-phase and single-phase induction motors as well as that of the double-cage motors are developed. The principles of such modern control methods as Fiel-Oriented Control, Direct Torque Control and Computed Charges Acceleration Method are clearly treated in this monograph. Numerous equations, simulations, and figures are presented.

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. The book will be rich in useful information, without an excessive mathematical burden. Computer simulations resulting in mock oscillograms of physical quantities are used for illustration of basic control concepts. The content of this book is divided into three basic parts: 1) control-oriented description of induction motors, 2) control methods, and systems, 3) control means. An induction motor is presented as an electromechanical power converter, and basic relations between the electrical, magnetic and mechanical quantities in the motor will be explained. Control methods and systems will be classified according to the controlled variables(torque, speed, flux), actuating variables(voltage, current), and dynamic performance (uncontrolled, low-performance, and high-performance). An overview of power electronic converters and information processing equipment used in the modern induction motor drives is included. Such systematic approach will give the readers a comprehensive overview of the field of induction motor control.