GB695800A - Electric discharge valve mercury vapour current converters for obtaining large powers at high frequencies - Google Patents

Abstract

695,800. Converting. AKT.-GES. BROWN, BOVERI, & CIE. July 21, 1950 [July 21, 1949], No. 18303/50. Class 38 (ii). A grid-controlled electric discharge valve converter for operation at high frequencies is characterized in that a condenser is connected between the zero point of the primary winding of the converter transformer and the cathode of the converter, the magnitude of the condenser and of the stray inductance of the transformer are so chosen that in normal operation the direct current of the rectifier has interruptions. A direct current source 16 feeds the condenser 18 over an inductor 17 and is also connected to the cathode of the converter 23 and the centre taps of the primary windings of transformers 19, 20, 21, the secondaries of which supply-in parallel -a consuming network 22. The anodes of the converter are connected in pairs to the ends of the primary windings and operate three in parallel, the grids being energized from a suitable pulse source 24 and commutation effected by condensers 25, 26, 27. The provision of the condenser 18, of large capacitance, eliminates the effect of the inductor 17-and also the leakage inductance of the transformer, which should be very small, and ensures rapid de-ionization of the converter thus allowing the steepness of the rise and fall of the anode curve to be reduced and to be separated by current free intervals. The invention may also be arranged so as to operate from a three-phase supply.