Discussion on “a self-exciting alternator,” at New York, January 26, 1906

A. E. Kennelly: This paper is, I think, extremely interesting, because of the apparent simplicity of the means that have been adopted, not only for the exciting, but also for the compounding of the alternator described. The first dynamo machines were, of course, separately excited, and it was considered a great step to make them compounding. When alternators came into use, it was considered much more difficult to make them self-exciting, on account of the direct current required by the field, the armature producing alternating current. Self-exciting was considered more important for them than compounding, because in the case of alternators it was not the IR drop that had to be compounded, but the IZ drop; a two-dimension problem instead of a one-dimension problem, and therefore more difficult as the square, so to speak.