A　novel　zero-current　soft-switching　Buck　converter　was　proposed.　Zero-current　turn-off　for　the　main　switch　and　zero-current　turn-on　and　turn-off　for　the　auxiliary　switch　are　achieved　by　using　an　auxiliary　resonant　network,　and　the　main　diode　is　also　turned　on　under　zero-current.　The　switching　losses　are　greatly　reduced.　It　is　very　attractive　for　high　power　application　where　IGBT　is　predominantly　used　as　the　power　switches.　The　operation　principle　of　the　proposed　circuit　and　the　control　strategy　of　soft-switching　were　analyzed　in　detail,　and　the　design　considerations　were　explained　in　the　paper.　A　prototype　of　output　power　400W　was　built　up.　The　validity　of　the　proposed　technique　has　been　verified　by　computer　simulation　and　experimental　results.　©　2010　Chinese　Society　for　Electrical　Engineering.