The regulation of distributing transformers

With the many improvements made in distributing transformers during the past few years, especially since the advent of the so-called silicon steels (by the use of which the iron loss of transformers has been greatly reduced), the tendency has been to lay particular stress upon the iron loss characteristics, with the result that other electrical characteristics, such as exciting current and regulation, have scarcely received the attention that their importance deserves. In reviewing the published claims made by the various manufacturers, we find that the two last named characteristics have not been improved in the same proportion as the iron loss. While the author recognizes that both a low exciting current and good regulation are of great importance, this paper will be confined to a discussion of regulation; its relation to the other characteristics of distributing transformers and its effect on the economical operation of the modern central station.