Balancing Device of Alternating Current Source for Measuring Purposes

Abstract

The alternating current source for measuring purposes is usually unbalanced against the earth. The quiv lent circuit of the unbalanced alternating ourrent source is first considered and the idea of the physical and the easth eircuit is givon. By the aid of this idea, it is discussed whether we can make any alternating carrent source balaneed against the earth by connecting a su table network between the source and the load. The ordinary transformer is proved to be not suitable for this purpose on account of the distributed capacity between the primary and the secondary coils. Two kinds of balancing transformers are d scribed which were wocnd by the author with good resnlts. Finaily it is noticed that the retardation coil, if connected in shunt with the source and its middle point earthed, has slightly the effect of reducing the unbalance of the source.