特大型水电机组继电保护相关问题研究

Research on Related Problems of Protection for Super Large Hydropower Plant

随着我国700MW级水电机组陆续投入运行,发电机—变压器组(简称发变组)保护应用遇到了一些新的问题。本文针对注入式定子保护接地电阻测量值波动、主变压器低压侧零序电压保护受TV一次断线影响、主变压器零序差动保护TA极性难以校核、动态条件下转子绕组对地绝缘电阻误差大等若干问题进行了分析,给出了解决措施。实践经验表明,本文提出的方案较好地解决了现场问题,满足特大型水电机组安全稳定运行的需求。

With the construction of giant hydropower station in China,some 700 MW class hydropower units have been put into operation,some new situations in the protection of the generator transformer unit have been put forward. In this paper some issue has been discussed and gives solutions such as injection stator protection grounding resistance fluctuation,how to improve reliability of main transformer low voltage side zero sequence voltage protection,the polarity check of main transformer restricted earth fault（REF）protection,injection rotor protection grounding resistance fluctuation and etc. Practical experience shows that these solutions can solve the on-site problems and meet the needs of the safety and stability operation of large hydropower units.