For　the　bidirectional　full-bridge　CLLC　resonant　converter,　soft　switching　of　primary　side　and　secondary　side　switches　and　bidirectional　power　transmission　are　its　obvious　advantages.　However,　in　the　pulse　frequency　modulation　control　under　light-load　conditions,　the　converter　will　have　the　disadvantages　of　output　voltage　imbalance　and　low　transmission　efficiency.　In　order　to　improve　the　range　of　voltage　regulation　and　efficiency　of　CLLC　resonant　converter　under　light-load　conditions,　a　novel　phase-shift　pulsewidth　modulation　method　is　proposed　in　this　article.　There　is　low　voltage　gain　regulation　and　low　operation　losses　can　be　achieved　under　light　load.　Considering　the　parasitic　parameters　and　dead　time　of　the　switches,　the　voltage　gain　of　the　proposed　control　method　under　light　load　is　precise　research　by　using　the　time　domain　analysis　method.　Finally,　an　experimental　prototype　of　a　bidirectional　full-bridge　CLLC　resonant　converter　with　200　V　input　voltage,　200　V　output　voltage,　and　a　rated　power　of　800　W　is　designed.　According　to　the　simulation　and　experimental　results,　it　can　be　shown　that　the　proposed　control　method　is　effective　under　light-load　operation.　©　1986-2012　IEEE.