Classification of Alternating-Current Motors

This paper points out that in order to arrive at a rational classification of alternating-current motors it is necessary to base all suggestions on one and the same theory. The author thinks that the component field theory is best suited to this purpose, and urges that it be always so applied as to bring out the very great similarity between the alternating-and the well understood direct-current machines. Descriptive names are suggested for some 44 alternating-current motors, including the principal forms of single-phase, polyphase, commutator and commutatorless machines now known. These names are such as to positively identify each of these machines. The rules followed in preparing the diagrams illustrating the various forms of motors and in selecting the proposed names, are given. In order to enable the reader to quickly judge of the aptness of these names, the theory of each of the motors dealt with is briefly outlined. It is thought that the information given will make it easy to correctly represent, describe and classify any motor which may have been omitted. It is further pointed out that the term ``repulsion'' as applied to motors, has never been defined, that no practical motors operate on what has been known as the repulsion principle ever since 1820, and that there is no justification whatsoever for the use of this term in connection with alternating-current motors. Such an indefinite term leads merely to endless confusion and should be abandoned.