The Relation of the Petersen System of Grounding Power Networks to Inductive Effects in Neighboring Communication Circuits

HE purpose of this paper is to present a simple theoretical treatment of those features of the Petersen method of grounding a power network which are of principal interest from the standpoint of inductive effects in neighboring communication circuits. In this method, the neutral of the system is grounded through an inductance which is in resonance, at the fundamental frequency, with the total direct capacity of the system to ground. The theory of the behavior of a power system thus grounded at times of accidental faults to earth has been developed by Petersen in a paper published in 1919,1 in which the results of field tests and of operating experience with an installation in G e r m a n y are also described. T h e method has also found application in other places in Europe, chiefly in Italy and Switzerland. It does not appear in any of these cases that inductive interference was a factor requiring, or at any rate receiving, consideration. In fact, it does not seem that either Petersen himself, or other engineers in Europe who have made use of his scheme, have considered it except as a method of protecting power systems from the effects of accidental grounds.