发电机转子磁极耐压试验放电原因分析与处理

铜街子水电站14号机组因运行年限较久，公司决定对其发电机定子、转子进行升级改造，对68个磁极也全部进行更换。新磁极为东方电机公司生产，现场对发电机转子磁极进行组装时，在耐压试验过程中，分别发现有4个磁极存在放电现象，随即对发电机转子磁极组装前的单个耐压试验、组装后的整体耐压试验过程中发生的放电现象进行了分析比对，从而找出了其存在放电现象的原因，即因杂质过多而导致的放电，并有针对性地提出了有效的处理方法。同时，也对后续相关设备进行类似试验的方法提出了建议。

Cause analysis of electrical discharge in voltage endurance test of generator rotor magnetic pole and treatment

As No.14 generator unit of Tongjiezi Hydropower Station has operated for a long period, the generator stator and rotor were decided to be upgraded, with 68 magnetic poles replaced as well. The new magnetic poles are manufactured by Dongfang Electric Machinery Co., Ltd.. In voltage endurance test while assembling of the rotor magnetic poles, electrical discharge phenomenon was found for four magnetic poles. The discharge phenomena of single magnetic pole voltage-endurance test before assembling and in the integral voltage-endurance test of the magnetic poles after assembling were compared and analyzed and it was found that the excessive impure substance was the cause of the discharge. According to the analysis results, the effective treatment measures are put forward. Innovative suggestions are also proposed for the follow-up similar tests of related devices. 