GB758440A - Electric current rectifier system - Google Patents

Abstract

758,440. Rectifying. STANDARD TELEPHONES & CABLES, Ltd. Dec. 30, 1952, No. 32966/52. Class 38 (2). A rectifying system having a constant or other predetermined output voltage characteristic comprises two primary windings P<SP>1</SP>, p<SP>2</SP> connected in series and wound on separate links of a saturable magnetic core so that they have separate magnetic circuits, one of the windings being shunted by a capacitor C, and two secondary windings S<SP>1</SP>, S<SP>2</SP> coupled to the primary windings and connected in series to supply a load G through rectifiers D and filter F. The arrangement exhibits a series resonance when the input voltage is such that it operates beyond the " knee " of the magnetic curve of cone material, and a parallel resonance far beyond that, the normal working range being between the two resonances but very close to the series resonance. The filter inductor should be arranged to act as an inductive load and winding S<SP>1</SP> should have many more turns than winding S2. Two similar secondary windings may supply the load through two full-wave rectifiers, Fig. 4 (not shown), or suitably connected secondary windings S<SP>1</SP>, S<SP>2</SP> may supply a rectifier arrangement D with a three-phase input in the Scott connected manner, Fig. 5. In another modification four secondary windings supply rectifiers in a six-phase manner, Fig. 6 (not shown). Curves showing the variation of the magnitudes of the phase-displaced voltage across the two primary windings and of the output voltage with change of input voltage are shown for no load and full load conditions, Figs. 7, 8 (not shown).