AN INTERLEAVED ISOLATED THREE-PHASE SEPIC DC-DC CONVERTER WITH COUPLED INPUT INDUCTORS
This paper presents the analysis of a three-phase interleaved SEPIC DC-DC converter with coupled input inductors and isolated by three single phase transformers. The number of magnetic components is reduced when coupled inductors are used in the input. Besides that, a reduced current ripple is achieved. A detailed theoretical analysis is presented describing the operation stages for a duty cycle from 2/3 to 1, in both continuous and discontinuous conduction mode. The effect of the coupling factor in the input current ripple and in the operation of the converter was also evaluated. A design example is presented for a 500 W converter with 80 V input voltage, 400 V output voltage and 40 kHz switching frequency. To validate the analysis,
some experimental results are also presented.