A new two-phase to six-phase transformer connection

Vladimir Karapetoff: A general solution of two-phase to six-phase transformation is shown in Pig. 1 presented with this discussion. O a, O b, O c, O d, O f, O g, are six “star” voltages desired to be had on the six-phase side. As a simplest case, imagine a six-phase synchronous motor adjusted to run at unity power factor and used as a load on a two-phase line. Then the foregoing six voltages may be considered, as those across the individual armature phases (star connected) of the motor. The problem of phase transformation consists in connecting the vertices of the hexagon by lines of two mutually perpendicular directions. Starting with point a, there are only three possible independent beginnings, viz., a b, a c, and a d. Beginning with a b, we have to draw a b, g c, f d, for phase I, and a f, b d, for phase II. This will give the figure drawn by dotted lines and identical with that shown in Boyajian's Fig. 1.² Beginning with a c, gives again a Φ figure shown in full lines. Beginning with a d, gives an identical Φ figure drawn in “dash and dot.” Thus, the Φ transformation is not one of several possible transformations, but the only possible perfect transformation.