During　the　operation　of　the　low　voltage　distribution　system,　the　occurrence　of　series　arc　faults　often　causes　line　damage,　grid　trips,　power　quality　degradation,　even　electrical　fires.　Aiming　at　the　change　of　electromagnetic　signal　when　arc　fault　occurs,　this　paper　analyzes　the　time　and　frequency　domain　characteristics　of　the　current　under　different　loads,　under　normal　operation　of　the　line　and　arc　faults.　When　an　arc　fault　occurs,　its　high-frequency　components　increase　significantly,　especially　under　non-linear　load　conditions,　which　is　regarded　as　the　characteristic　basis　for　arc　faults.　Combined　with　false　residual　current　detection　technology,　this　study　proposes　a　new　arc　fault　detection　scheme　by　simulating　the　magnetic　flux　distribution　of　a　high-frequency　current　transformer.　The　experimental　results　show　that　this　method　is　effective　in　detecting　arc　fault.　This　provides　a　new　idea　for　arc　fault　detection　technology.　©　2021　IEEE