GB322775A - Apparatus for regulating voltage in alternating current distribution systems - Google Patents

Abstract

322,775. Pollak, J. E., (Ganz-Fele Villamossagi Reszvenytarsasag). June 1, 1928. Divided on 322,199, [Class 38 (ii), Electric currents, Converting &c.]. Electric transformers; systems depending on static transformers. - The output voltage of transformers with tapped secondaries is controlled by two chokes I, II each with a closed flux path, or by one choke with two closed flux paths, the paths having main coils f<1>, f<2> and auxiliary coils g<1>, g<2>. The main coils are in series across tappings L', L<2> on the secondary of the .transformer with their junction connected to a line L<3> on which the voltage is regulated by short-circuiting one of the coils g<1>, g<2>, gradually over a resistance k', k<2> or instantaneously by a switch. When neither coil is shortcircuited, voltage drop dependents on load current in the main coils 'is avoided by so interconnecting the coils g<1>, g<2> that the currents in the coils g<1>, g<2> equalize the flux in the cores I, II, equal fluxes producing equal and opposed voltages in the coils g<1>, g<2>. The interconnection is broken simultaneously with the short-circuiting of either coil, the switches h being mechanically connected as shown. The resistances k', k<2> may be water resistances. More than two chokes with auxiliary coils successively short-circuited may be used. In a modification, the branches of the cores I, II adjacent in Fig. 1 are united to form a centre limb of a single for the coils f<1>, f<2>, g<1>, g<2>. To avoid the voltage drop dependent on load when neither coil g', g<2> is short-circuited, a coil on the centre limb is short-circuited by a switch positively connected to the switches for the coils g<1>, g<2> so that the short-circuit of the coil on the centre limb is broken when either coil g', g<2> is short-circuited. Reference has been directed by the Comptroller to Specification 126,744, [Class 38 (ii), Electric currents, Converting &c.].