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The principle and primary features of high-resistance type voltage differential protection is introduced incorporating the misoperation problem of generator differential protection in the electrical tests in the while-set staring of No.2 generating set in Yahekou Power Plant. Through the cause analysis on this rare event, the meathod to solve the misoperation problem is illustrated, thus the experience was accumulated for treing similar problems. 结合鸭河口电厂2号机组在整套启动进行电气试验时发电机差动保护出现误动问题,着重介绍了高阻型电压差动保护的原理和主要特点。通过对这一少见事件的原因分析,阐述了解决误动问题的办法,为今后处理类似问题积累了经验。 A misoperation of main transformer relay in a power station caused by the fault in secondary circuit is introduced. Trough the check of the main transformer exit relay, its correlative circuit and secondary circuit, it is found that the misoperation is caused by the AC current flowing into the DC circuit and activating the intermediate relay. The accident is analyzed by experiments and the following two solutions are presented. a. Substituting the freewheeling diode between the two terminals of intermediate... A misoperation of main transformer relay in a power station caused by the fault in secondary circuit is introduced. Trough the check of the main transformer exit relay, its correlative circuit and secondary circuit, it is found that the misoperation is caused by the AC current flowing into the DC circuit and activating the intermediate relay. The accident is analyzed by experiments and the following two solutions are presented. a. Substituting the freewheeling diode between the two terminals of intermediate relay by RC circuit so as to eliminate the contact bouncing caused by AC; b. Reconstructing DC system. The first solution is tested and it shows that there is no influence on relay performance characteristics. It is used to avoid this kind of misoperation problem in power station and has good effect. 介绍了某发电厂由于间隔二次回路故障引起的主变保护误动事故。通过对主变出口继电器及其回路、二次回路的检查 ,找出了事故的原因 :由于交流量窜入直流控制回路引起中间出口继电器动作从而造成主变保护动作。通过试验对事故进行了分析 ,并提出了 2种防范措施 :方案 1为将出口中间继电器两端的续流二级管改为RC回路 ,从而避免由于交流量引起的中间出口继电器的抖动 ;方案 2为对直流系统进行改造。验证结果表明方案 1不会影响保护的动作特性。现场采用方案 1解决交流量窜入直流回路引起的保护误动问题 ,取得了良好的效果 The sliding misoperation of operating mechanism in moulded case circuit breaker(MCCB) was one of the design problems avoiding as much as possible.By using ADAMS simulation software,the simulation study of one-type MCCB was carried out,the causes of sliding misoperation of operating mechanism were expatiated.By(using) the multi-body dynamic software package to test,the proposed solution was verified.The result shows that the design approach to be put forward can solve said sliding misoperation problem effectively.... The sliding misoperation of operating mechanism in moulded case circuit breaker(MCCB) was one of the design problems avoiding as much as possible.By using ADAMS simulation software,the simulation study of one-type MCCB was carried out,the causes of sliding misoperation of operating mechanism were expatiated.By(using) the multi-body dynamic software package to test,the proposed solution was verified.The result shows that the design approach to be put forward can solve said sliding misoperation problem effectively. 塑壳断路器操作机构的滑扣问题是断路器设计中的核心问题之一,需要尽力避免。通过运用ADAMS仿真软件,对某型号断路器进行了仿真研究,阐述了其机构滑扣的原因,并提出解决方案。试验结果表明,所提出的设计方法能够有效解决塑壳断路器滑扣问题。
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