根据励磁涌流的特点构成的变压器差动保护有（   ）种。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69017' and id < 4467174 and id<>'4467174' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69017' and id > 4467174 and id<>'4467174' order by id asc limit 5