Nowadays,　the　present　wind　farm　topology　still　faces　some　economic　and　reliability　problems,　such　as　the　long　distance　delivery　cost,　cable　reactive　current,　too　many　power　electronics　devices,　and　so　on.　Taking　into　account　the　reliability　and　economy,　this　study　presents　a　topology　that　high-voltage　variable-speed　squirrel　cage　wind　turbines　are　directly　integrated　into　the　DC　collecting　line,　then　an　equipped　DC-DC　converter　at　the　terminal　of　wind　farm　boosts　the　DC　voltage　and　feeds　out　the　DC　power　to　regional　wind-energy　DC　collection　centre.　After　the　topology　of　DC　wind　farm　is　determined,　this　study　designs　field-oriented　control　and　hysteresis　modulation　to　achieve　maximum　power　point　tracking　target.　After　that,　collecting　line　fault　characters　are　analysed　and　the　reference　for　protection　scheme　is　summarised.　The　simulation　and　verification　here　are　based　on　Simulink　platform.　©　2017　Institution　of　Engineering　and　Technology.　All　rights　reserved.