This　paper　introduces　how　doubly-fed　wind　farms　can　compensate　for　reactive　power　demands　of　the　grid　during　low　voltage　ride　through　(LVRT)　events,　thereby　providing　voltage　support.　This　capability　significantly　influences　the　assessment　of　voltage　sag.　To　address　this,　this　paper　proposes　a　method　for　assessing　voltage　sags　in　the　power　grid　that　considers　the　voltage　support　capabilities　of　doubly-fed　wind　farm　during　LVRT.　This　method　accurately　characterizes　the　voltage　support　capability　during　LVRT　by　establishing　a　dynamic　equivalent　model　of　the　wind　farm.　For　each　wind　farm,　the　clustering　is　based　on　the　Crowbar　status　determination　as　the　primary　clustering　criterion,　while　the　interconnected　voltage　at　the　point　of　common　coupling　(PCC),　considering　the　mutual　influence　among　multiple　wind　farms,　is　used　as　a　correction　factor　for　iterative　clustering.　By　utilizing　collaborative　equivalence　of　multiple　wind　farms,　the　final　dynamic　equivalent　model　is　determined.　Subsequently,　a　comprehensive　simulation　of　various　grid　fault　scenarios　is　conducted　to　evaluate　the　voltage　sag.　The　proposed　method＇s　accuracy　and　effectiveness　have　been　validated　through　case　studies.　©　1986-2012　IEEE.