中性点直接接地系统中，常见的操作过电压有（    ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69491' and id < 4501671 and id<>'4501671' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69491' and id > 4501671 and id<>'4501671' order by id asc limit 5