Performance of Auto Transformers with Tertiaries Under Short-Circuit Conditions

The problem of operating many of the present day transformers designed and built to function in sizes and under conditions unheard of only a few years ago, is now of prime importance to many of the larger power companies. A statement of one type of the operating troubles encountered in the larger sizes is discussed in this paper and data taken as far as practicable under operating conditions is given. From experience so far gained it is thought that both the autotransformer and the grounded neutral system are here to stay and such problems as they present merit considerable investigation under actual working conditions. The present paper presents rather than solves one type of trouble encountered.