THREE-PHASE TRANSFORMER SET Russian patent published in 2002 - IPC

FIELD: transformers for high- power converter substations. SUBSTANCE: transformer set has two electrically interconnected active parts of which one is made in the form of autotransformer incorporating common and series windings. Second part is made in the form of converter transformer. Autotransformer common winding is delta-connected and series winding is connected in zigzag with initial point. Transformer set has three groups of fixed contacts same as number of transformer-set phases; each group includes three contacts, first one being used for connecting voltage bushing, second contact, for connecting delta top of common autotransformer winding, and third contact, for connection of zigzag starting lead. Transformer set is equipped with junction members designed for interconnecting contacts of like-polarity phases in pairs and contacts of at least two unlike-polarity phases. EFFECT: provision for parallel running of converter in multiphase rectifier mode along with deep voltage regulation. 3 dwg