SELF-COMMUTATED TWELVE-PHASE CONVERTER Russian patent published in 1994 - IPC

FIELD: current converters. SUBSTANCE: converter has two three-phase bridges 1, 2 on the base of turn-off rectifiers, in particular, on the base of turn-off thyristors, two three-phase three-winding transformers 4, 5, two three-phase three-winding capacitor batteries 6, 7 and three reactive two-terminal networks 8. Primary and tertiary windings 9 and 10 correspondingly of both transformers are made identical. Secondary winding 1 of the first transformer has a star connection, winding of the second transformer - delta connection. Bridge on the base of turn-off thyristors and capacitor battery are connected in parallel to any secondary winding. Outputs with the same polarity of tertiary windings of both transformers are connected one to another through identical reactive two-terminal networks which are made in such a manner that in voltages of capacitor batteries the fifth and the seventh harmonics would be close to zero. Overvoltages are effectively restricted due to connection of reactive two-terminal networks induced by forced current commutations. EFFECT: improved reliability of operation of the converter. 2 tbl, 1 dwg