Computer-Aided Design of Magnetic Circuits

The general purpose of this book is to present the reader to the field of computer-aided design frame an industrial viewpoint. All computer-aided design work has the common function of providing results that extend the engineer's ability to build and sell devices and equipment. However, each technical area has its own specialized techniques and problems, and the particular purpose of the book is to present those for the design of magnetic circuits.

After stating the design problem, the book discusses the pertinent assumptions, equations, and models; develops methods for handling the interface with the attached electric circuits and the sequence of steps for computer-aided design; and finally presents the flow diagrams and typical input and output forms in use.

The chapters are so arranged that the simplest magnetic-circuit device, the reactor, is considered first, followed by leakage-reactance transformers and regulating transformers. The last chapter covers conventional multiwinding transformers. For each class of device, the theory and modeling are treated, followed by numerical examples and the approach to computer-aided design. Many examples are oriented toward lamp ballasts, because their magnetic-circuit operation is realistically complex and because most of the problems were prepared for their design.

The authors originally developed the computer programs presented here for actual industrial use, in reducing design time for new transformers, in exploring new magnetic-circuit configurations, and in obtaining more accurate designs to reduce cut-and-try work on prototypes. To accomplish this, much preliminary work was necessary to develop analytical techniques and mathematical models for the magnetic circuits and the electric circuits in which they were placed. The mere transfer of hand-design methods to computer programs would not have been successful in yielding useful and realistic computer-aided design methods.