VALVE-TYPE CONVERTER Russian patent published in 1998 - IPC

FIELD: AC-to-DC or AC-to- variable-frequency power conversion, primarily for adjustable electric drives. SUBSTANCE: converter has two conversion circuits whose inputs are connected in parallel and outputs, in series or in parallel. Each conversion circuit incorporates series-connected three-phase bridge rectifier provided with ac input filter, secondary windings of three-phase input transformer whose primary windings are connected, respectively, in star and in delta, ac filter of off-line inverter, and off-line three-phase bridge inverter with storage filter in DC voltage section. Converter load is connected to outputs of three-phase bridge rectifiers. Various mechanical design forms of converter are proposed: those with off-line three-phase inverter functioning as voltage or current inverter, as well as with reversing three-phase bridge rectifiers. Converter provides for sine-wave input current cophasal with voltage in all modes of operation and adjustment of DC output voltage within entire range. EFFECT: provision for DC output voltage reversal, shaping of desired waveform of AC output voltage, increased maximum output power. 4 cl, 5 dwg