Several　large-scale　wind　turbine　tripping　accidents　occurred　in　Jiuquan　wind　power　base　in　2011.　According　to　the　on-site　survey　and　the　oscillogram　analysis,　the　cause　of　these　accidents　is　the　short-circuit　fault　of　electrical　equipment　and　cables　in　wind　farm,　which　leads　to　the　voltage　drops　in　the　farm　and　system,　therefore　a　large　number　of　wind　turbines　trip　because　they　do　not　have　the　low　voltage　ride　through　(LVRT)　capability.　After　the　fault　is　cleared,　a　large　number　of　wind　turbines　trip　again　when　the　system　voltage　rises　to　setting　point　of　overvoltage　of　wind　turbine,　because　the　reactive　power　compensation　device　in　wind　farm　step-up　substation　can　not　timely　regulate　the　voltage　automatically.　Accordingly,　wind　turbine　retrofitting　and　collector　system　and　its　protection　configuration　improvement　are　put　forward　from　a　practical　point　of　view,　and　combining　with　the　characteristics　of　large-scale　wind　power　base,　the　subjects　to　prevent　wind　power　reasonably　from　large-scale　tripping　are　also　put　forward　for　further　research.