Unmanned　Aerial　Vehicle　(UAV)　frequently　encounter　various　external　disturbances　during　flight.　After　experiencing　such　disturbances,　the　UAV’s　power　supply　must　quickly　respond　and　maintain　stable　output.　To　address　this　problem,　this　paper　proposes　an　improved　active　disturbance　rejection　control　(IADRC)　scheme　combined　with　peak　current　mode　control　(PCMC)　based　on　a　six-phase　interleaved　parallel　synchronous　buck　converter.　Modal　analysis　was　conducted　on　the　synchronous　buck　converter,　and　small-signal　modeling　was　performed　under　current　control　mode　to　analyze　closed-loop　stability.　The　dynamic　response　speed　was　improved　by　utilizing　a　peak　current　inner　loop,　enabling　precise　current　sharing.　The　system’s　disturbance　rejection　capability　was　enhanced　by　employing　an　improved　extended　state　observer　for　real-time　estimation　of　disturbances.　This　approach　offers　advantages　such　as　high　dynamics,　strong　disturbance　rejection,　and　good　current　sharing.　Finally,　an　experimental　prototype　with　a　rated　power　of　1000　W,　maximum　efficiency　of　96.9%,　and　power　density　of　12.9　W/cm2　was　constructed.　Comparing　three　different　control　schemes,　the　response　waveforms　of　the　prototype　verify　the　feasibility　and　advancement　of　the　scheme　in　this　paper.　©　2025.　The　Author(s).