As　Type-3　wind　turbine　(WT)　has　already　become　a　typical　type　of　highly　penetrated　power　sources　in　modern　power　systems,　characterizing　its　properties　during　grid　fault　is　a　basic　requirement　for　system　analysis.　However,　many　significant　factors　have　not　been　considered　in　the　existing　analytical　methods　and　results,　such　as　various　switching　of　internal　control　and　protection　circuits　in　low　voltage　ride　through　(LVRT)　solutions.　In　this　paper,　performance　of　Type-3　WT　during　LVRT　is　first　illustrated　and　summarized　as　the　sequential　switching　characteristic　in　multi　time　scales,　viz.,　instant　control,　ac　control,　dc　voltage　control,　and　rotor　speed　control　time　scales.　Thus,　for　magnitude　drops　in　stator　voltage,　a　mathematical　model　is　proposed　to　understand　this　characteristic　and　fault　current　analysis＇s　features.　Then,　an　analytical　method,　based　on　the　operational　inductance,　is　proposed　so　that　fault　current　components,　with　the　sequential　switching　considered,　can　be　depicted　with　a　unified　and　simple　analytical　expression.　By　identifying　magnitude　of　symmetrical　current,　the　transient　and　steady-state　equivalent　circuits　of　Type-3　WT　are　proposed　to　estimate　momentary　current　and　electrical　power　approximately.　Finally,　analytical　results　are　verified　by　comparisons　with　real-time　simulation　results　of　a　detailed　1.5　MW　WT　model　in　RT-LAB.　©　1969-2012　IEEE.