Family of single‐phase high‐frequency isolated AC–AC converters

摘要

Abstract This work presents a family of single‐phase ac–ac converters with high‐frequency isolation based on the association of interleaved transformers and the dual active bridge (DAB) converter. From distinct configurations of the dc link in terms of half‐bridge (HB), full‐bridge (FB), and interleaved full‐bridge (IFB) arrangements, one can obtain three symmetrical and six asymmetrical structures, with distinct trade‐offs among the number of active switches, total dc‐link voltage, and effective operating frequency of the filter elements. Prominent advantages of the derived circuits include input power factor correction (PFC), a nearly sinusoidal load voltage, the operation of active switches under soft‐switching condition during part of the line period, reduced current stresses, good current sharing due to the interleaved transformers, as well as multilevel voltage waveforms on both sides of the high‐frequency transformer (HFT). Experimental results obtained from an experimental prototype of an ac–ac FB‐IFB converter are presented to validate the theoretical assumptions.