下列无功电源比较中，电压调节效应为负的是(  )。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69512' and id < 4503290 and id<>'4503290' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69512' and id > 4503290 and id<>'4503290' order by id asc limit 5