AC-TO-DC VOLTAGE CONVERTER (VERSIONS) Russian patent published in 2009 - IPC H02M7/155 

FIELD: electricity.

SUBSTANCE: invention deals with design of converter equipment; its implementation is to provide for conversion of three-phase ac voltage to 6-pulse or 12-pulse dc voltage at two rectifier diodes with the voltage thyristor-regulated on the group transformer input side. Under the first (6-pulse) design version the converter comprises two single-phase transformers, an additional pair of controllable gates, connected in parallel opposite and a secondary winding. One end of each single-phase transformer primary winding is connected to the phase input terminal and the other - to the common point of the controllable gate pair connected in parallel opposite; via the said common point the primary winding is connected to the opposite input terminal. The common points of the controllable gates serve to close the series circuit composed of all the gates specified and one of the primary windings. The secondary winding central and end outputs are connected to a double-diode rectifier. The secondary winding common cavity contains one core with each transformer's primary winding. Specificity of the second version (12-pulse) converter consists in it comprising four additional pairs of the aforesaid type gates and two additional primary windings, one of them applied on one transformer and the other, with a -fold greater number of coils - on the other. The winding are connected via the corresponding gate pairs, the major - between the phase and the zero input terminals, the minor - between the phase input terminals. Each main primary winding contains an intermittent terminal that breaks down its total number of coils at a ratio of with the major portion counted from the loose phase input terminal. The intermittent terminal is connected to the zero input terminal via a corresponding gate pair. The both design versions allow of usage of a varied design homotypic magnetic circuit pair including a two-limb core with sectioned primary and secondary windings. The third (6-pulse) converter design version differs from the first one due to it envisaging additional embedment of an identical single-phase transformer restricting the diversity of magnetic circuits used; all the three primary windings alongside with the controllable gates (joined in parallel opposite) delta-connected with the delta vertices linked to the phase input terminals. With regard to a 12-pulse converter design the third version envisages each primary winding having an intermittent terminal that breaks down its total number of coils at a ratio of and connected to the zero input terminal via the aforesaid additional gate pair.

EFFECT: conversion process simplification combined with improved current usage at uniform distribution of current between the rectifier diodes.

16 cl, 8 dwg