In recently,inductorand transformeris the common deviceusing widely in thephotovoltaic system and powerelectronics.Therefore,eachinductorandtransformerhasdifferentcorelossandironlossdependingon the size and kinds ofcore materials,itis importantto analyze loss characteristics forbettertransformer efficiency.This paper offers an efficiency calculation method for PCS inductor and transformer loss,and differentkindsofcorematerialsareanalyzedforoptimizedPCS design