摘要
为利用有限的土壤面积尽可能的降低直流接地极的跨步电压,以圆环形直流接地极为研究对象,提出了一种地中敷设绝缘层以降低跨步电压的方法。结合矩量法和边界元法对敷设绝缘层的接地极性能进行了分析,并通过现场实验验证地中绝缘层降低跨步电压的有效性。计算结果表明:地中敷设绝缘层能够有效抑制接地极入地电流流入表层土壤,从而均衡地表电位,降低跨步电压;在不增加任何其他措施的情况下,采用U形绝缘层能够有效降低直流接地极跨步电压10%以上,且该方法对接地极本身性能的影响较小。
In order to make the best use of the limited ground area to decrease the step voltage induced by DC grounding electrode, taking the toroidal DC grounding electrode for example, we proposed a method of laying underground insulating layers. The performance of grounding electrodes with underground insulating layers was calculated using the moment method and the boundary element method, and then tested in field experiments. The calculation results shows that underground insulating layers can efficiently prevent the grounding current from flowing into surface soil, and hence balance the surface potential of ground and decrease step voltage. In addition, without any other setups, merely using a U-shaped insulating layer can reduce step voltage by more than 10%, and hardly impact on the performance of grounding electrodes.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第7期1940-1947,共8页
High Voltage Engineering
基金
国家电网公司科技项目(20091514)~~
关键词
直流接地系统
跨步电压
地中绝缘层
数值分析
接地电阻
接地极温升
DC grounding system
step voltage
underground insulating layers
numerical analysis
grounding resistance
temperature rise of grounding electrodes