Engineers have developed many types of models to help themselves in visualizing and analyzing the performance of electrical machhlery. The significance of these models arises out of the economic importance associated with high performance in rotating machinery. Likewise, many of the technical problems encountered in the improvement of rotating machinery performance are such that one would hesitate in attempting a direct analytical solution.
The type of model employed has varied between the strictly mathematical (equations), the vector diagram, the locus plot and the equivalent circuit. The circumstance and complexity of the problem have usually dictated which of these was to be used. Not infrequently the past practice of the individual engineer is the sole reason for a selected procedure.
In his latest book Kron sets forth the results of a decade in which he has studied mathematically developed equivalent circuits to uncover their fundamental similarities. This work has resulted in a non-mathematical representation of models. Although the term "tensor" is not used in this representation, and although there are no matrices of mathematical symbols, the tensor idea is expressed by means of electrical circuit symbols. Multimesh circuits of electrical impedance combinations are used as models of machines and interconnections of machines.
The author shows how currents, fields, and torques can be computed directly by the use of their equivalent models. In preparation for this step the principles are given for determining a representative model and for insuring that true equivalence has been achieved by it.
The reviewer feels that there is much elegance in Kron's methods and that the research directed toward the development of electrical machinery may be furthered by their application. However, this book could be written in a more understandable form. Had the vohmie included more words of explanation in all sections, it would have conveyed more information and would have brought the author's ideas within the reach of a greater number of engineers. As it stands, a great deal of patience is required on the part of the reader. One is forced to read and reread the author's brief statements in order to draw out the numerous implications. Considering the prodigious amount of work done by the author in arriving at his generalizations, it is clear that much of the intermediate and practical work has been omitted. The inclusion of this material for illustrative purposes would have made a better presentation. The book's short length, its summary form and lack of any kind of index places it in the catagory of a monograph rather than a text or reference book.
C. W. HARGENS