500 kV GIS断路器打压频次异常解体分析

Disintegration Analysis of Abnormal Pressure Frequency of 500 kV GIS Switch

为查明D换流站500 kV GIS开关机构打压频次升高异常原因,对该机构进行解体。阐述了在开关机构高压油、低压油作用下开关储能、分闸、合闸的过程,基于开关机构各部件的结构,分析了高压油、低压油与各部件的连接关系,并分类讨论了各部件发生密封缺陷时低压油腔的表象。基于本次机构解体低压油腔反油现象,将发生密封缺陷的部件定位于柱塞油泵附近,并将该部位进行拆解,最终检查出有细微杂质附着于低压油滤网中,从而推断缸体内有杂质影响油泵高压密封性,导致机构打压频次升高。根据解体分析,运维人员应提高对开关打压频次异常升高的警惕性,为同类缺陷处理争取更充裕的时间,保证电网可靠、稳定地运行。

To find out the cause of abnormal increase of pressure frequency of 500 kV GIS switch mechanism in D converter station,the mechanism was disintegrated.In this paper,the process of switching energy storage,shutting and closing under the action of high-pressure oil and low-pressure oil of the switching mechanism are expounded.Based on the structure of each component of the switching mechanism,the connection relationship between high-pressure oil and low-pressure oil and each component is analyzed,and the appearance of the low-pressure oil cavity when the sealing defect occurs in each component is discussed.Based on the phenomenon in the low-pressure oil chamber during the disassembly of the mechanism,the parts with sealing defects are located near the plunger oil pump and the part is disassembled.Finally,it was found that there were fine impurities attached to the low-pressure oil filter screen.It can be inferred that impurities in the cylinder block affect the high pressure sealing of the oil pump,leading to the increase of the mechanism pressurization frequency.According to the disassembly analysis,the operation and maintenance personnel shall be more alert to the abnormal increase of switch voltage suppression frequency,so as to gain more time for the treatment of similar defects and ensure the reliable and stable operation of the power grid.