CAJ | 학술논문

单元件横差保护是一种简单灵敏的反应匝间短路等发电机定子绕组内部故障的主保护。分析了发电机单元件横差保护的基本原理,阐述了二滩水电厂大型水轮发电机单元件横差保护的具体配置。描述了一起由于发电机失磁引起的单元件横差保护误动事件,结合保护动作时和后期试验时的故障录波数据,对保护的动作行为进行了详细分析。根据分析结果给出了合理的改进措施：在不改变保护配置的情况下对整定值进行修改;结合发电机保护装置改造对保护原理进行改进。现场试验和机组运行实践证明了改进措施的可行性和有效性。
단원건횡차보호시일충간단령민적반응잡간단로등발전궤정자요조내부고장적주보호。분석료발전궤단원건횡차보호적기본원리,천술료이탄수전엄대형수륜발전궤단원건횡차보호적구체배치。묘술료일기유우발전궤실자인기적단원건횡차보호오동사건,결합보호동작시화후기시험시적고장록파수거,대보호적동작행위진행료상세분석。근거분석결과급출료합리적개진조시：재불개변보호배치적정황하대정정치진행수개;결합발전궤보호장치개조대보호원리진행개진。현장시험화궤조운행실천증명료개진조시적가행성화유효성。
The unit-transverse differential protection (UTDP) is a simple and sensitive main protection responding to inter-turn short circuit and other internal faults of generator stator winding. The operation principle of UTDP is analyzed, and the specific configurations of UTDP of generator at Ertan Hydropower Plant are presented. A misoperation case of LTTDP caused by field loss fault of a generator is described. According to recorded data of the protection misoperation and the following test, the protection operation action is analyzed in details. Reasonable improvement measure based on the analysis results is given, such as modifying the setting without change of present protection configuration and reforming the protection principle combined with the technical innovation of generator protection device. Field test and generator operation proves the feasibility and validity of the improvement measure.