GB120677A - Improvements in and relating to Systems of Electrical Distribution. - Google Patents

Abstract

120,677. British Thomson - Houston Co., (General Electric Co.). Feb. 5, 1918. Transformers. - In a high-frequency electric supply system, an alternator having a number of independent armature circuits arranged in groups connected to the load through a transformer whose primary is composed of a number of groups of independent windings, each winding being in a completed electric circuit with one armature circuit only, thereby preventing the direct flow of cross currents in the armature circuits. An alternator having thirty-two independent armature circuits has them arranged in four groups of eight; one of these groups is shown in Fig. 3, the armature circuits 14 being connected to bus-bars 17. The transformer windings are similarly grouped into sets of eight primary and secondary coils. Each primary coil consists of eight conductors 15, each of which is connected at one end through the bars 17 to one armature circuit only, the other ends of the eight conductors are connected in common to a binding-post 18 and through a reactance coil 19 to earth. The binding-posts are connected by a common return to the other ends of the armature circuits. The secondary windings are connected to sets of bus-bars, the groups of secondaries being arranged in series, parallel, or seriesparallel. The transformer is mounted on top of the alternator. In building the transformer the primary is made of cables having eight conductors and the secondary of cables with four conductors. These may be placed alternately and parallel to one another, or, as shown in Fig. 6, the primary and secondary coils P, S may be spirally arranged, the secondary being outside the primary