A universal power circle diagram

The usefulness and utility of the conventional power circle diagram can be expanded by translating the origin from the zero of power to the center of the circle. This operation makes all the circles concentric so that they can be printed beforehand on standard sheets of paper. Data for a particular problem then are plotted on the sheet as required. Because of the number of circles that are available immediately, the diagram also can be used for solving problems in which either the receiving- or sending-end voltage is a variable. Such solutions are aided by the plotting of auxiliary loci, which are either straight lines or circles, for constant loss, constant power, constant power factor, and so forth.