Research on Magnetic Leakage Field and Control Measures in High Capacity Transformer for VSC-HVDC transmission

A transformer for VSC-HVDC transmission (VSC-transformer) with large capacity of 480 MVA was taken as the research object in this paper. A full scale three-dimensional simulation model was established in software of infolytic magnet. The magnetic flux leakage distributions on iron core, clamp, oil tank and other structural parts of VSC-transformer were simulated and analyzed by field-circuit coupling method. The loss distribution of main structural parts was also compared. The influence of different shielding materials and shielding methods on the distribution of magnetic flux leakage was analyzed, and the measures to optimize the magnetic flux leakage of transformer were proposed to avoid local overheating phenomenon in VSC-transformer with large capacity.