H，H，M=3H的耦合电感在次级短路时，初级等效电感为（   ）H。

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69474' and id < 4499625 and id<>'4499625' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69474' and id > 4499625 and id<>'4499625' order by id asc limit 5