CONVERTING DEVICE Russian patent published in 2003 - IPC

FIELD: converter engineering for high-voltage ac substations. SUBSTANCE: device designed to convert three-phase-to-single-phase current has two rectifier-inverter sets each incorporating multiple-winding three-phase transformer connected to supply mains buses, unit of two series-connected rectifiers, inverter unit, dc unit, and single-phase transformer unit. The latter three units are sectionalized so that each inverter unit has three parallel-connected single-phase voltage inverters. Connected to outputs of each inverter is primary winding of single-phase transformer. Secondary windings of all three single-phase transformers in each section are interconnected in series and connected to load buses. Inputs of each inverter unit are connected to buses of respective dc unit section. Rectifier units of rectifier-inverter sets are connected in series. In addition series circuits formed by higher-harmonic filters of two sections in each set are integrated into common series circuit with common point through common smoothing reactor and are connected to common point of series- connected rectifier units. Output terminal of one of rectifiers in each set isolated from adjacent rectifier is connected to smoothing reactor of like-polarity dc unit section. EFFECT: enhanced efficiency due to improved characteristics of dc unit. 1 cl, 3 dwg