Inductors　are　very　critical　for　the　size,　weight,　and　the　efficiency　in　PV　inverter　system.　The　loss　models　of　high　frequency　eddy　current　loss　and　the　core　loss　of　laminated　silicon　steel　were　built　for　both　line　frequency　and　high　frequencies　excitations.　Then　the　total　losses　were　analyzed　which　have　complex　relationship　with　winding　turn　numbers,　foil　thicknesses　and　the　power　ratings.　Finally,　the　equivalent　European　efficiency　considering　the　inductor＇s　effect　itself　was　analyzed　to　get　the　maximum　EU　efficiency　for　inductor　winding　design.　The　analysis　and　the　results　were　based　on　a　500kVA　3-phase　PV　inverter.