Machine synthesis: An encounter with an idea

THE PROBLEM of designing a lamination and knowing how large to make a given motor is always a troublesome one, considered from a purely theoretical point of view. It is true that design texts make use of a D²L equation, using the diameter and length to fix the volume, if not the proportions, of an armature of a polyphase induction motor. But so few data are given on the factors making up D²L, that the method can hardly be considered reasonably exact.¹