摘要
传统高压单芯电缆设计分段长度偏短,导致电缆接头数量急剧增加,造成接头价格昂贵,工程投资随之上升,电缆运行的故障概率也相应提高,增大单段长度可有效解决这一问题。对金属护套感应电压和护套环流进行计算研究,推算出最大可能的敷设段长。使用解析公式和仿真计算两种方法,对220kV输电线缆在不同的接地方式、不同的排列方式下的金属护套感应电压进行计算,给出了可行的最大敷设段长,并对两种计算方法所得结果进行了对比。分析了负载不平衡或段长不平衡对护套环流的影响,对段长增加后不平衡负载或段长时的护套环流进行了仿真计算,提出最大敷设段长的选取还应考虑不平衡状态下的护套环流是否超限。
The number of the connectors grows sharply because of the short segments in the traditional cable, which causes the cost of the project to rise because of the high price of the connector. Meanwhile, the fault probability goes up when the cable working. For the problem, the research on increasing the segmented length in the highvoltage cable is carried out. Simulation and formula two methods are used to calculated the inducted voltage in the metal sheath of the high-voltage single-core cable under the different grounding and arranging style, with the rated voltage 220 kV. Then the largest segment length is calculated and the results from the above two methods are compared. The imbalance of load or segment length affects the circulating current in the sheath, and it is counted in load or segment length imbalance or both imbalances with the biggest segment length. The result illuminates the sheath circulating current bigger than that of the smaller segment, and it may be beyond the limit. So the circulating current in imbalance staus should be considered as well.
作者
高飞
黄磊
张蕾
张瑞永
刘静
吴述关
GAO Fei;HUANG Lei;ZHANG Lei;ZHANG Ruiyong;LIU Jing;WU Shuguan(Nanjing Power Supply Company,Nanjing 210019,China;Jiangsu Electric Power Design Institute,Nanjing 210036,China;School of Electrical Engineering,Southeast University,Nanjing 210096,China)
出处
《电气应用》
2020年第7期79-85,共7页
Electrotechnical Application
基金
国网江苏省电力公司科技项目(52100117001W)。
关键词
高压电缆
增加段长
护套感应电压
护套环流
三相不平衡
high voltage cable
increase section length
sheath induced voltage
sheath circulating current
threephase imbalance
