An Iterative Algorithm for Optimum Design of High Frequency Transformer in SST Application

The transformer industry is now gearing up to develop Solid State Transformer demanded by the evolving smart grid. The design of High Frequency Transformer (HFT) which is the key element in SST is a complex task because of the selection of optimum frequency, flux density, core material etc. This paper proposes an algorithm for the design of HFT at minimum Total Owning Cost. The algorithm is validated for 1000kVA, 11kV/415V three- phase wound core dry type transformer. Core materials considered are Amorphous, Nano crystalline and Special grade Silicon steel. The result obtained is compared with power frequency transformer of the same rating. Proposed design saves around 52% in TOC, 67% in manufacturing cost and 71% in weight (excluding the converter-inverter sections).