三相交流电源对称的条件是（   ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69036' and id < 4471223 and id<>'4471223' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69036' and id > 4471223 and id<>'4471223' order by id asc limit 5