电网技术Issue(4)：1174-1179,6.
高压直流输电接地极溢流特性
Current Overflow Characteristics of Earth Electrodes for HVDC Transmission System
摘要
Abstract
To research the influencing regularity of types and parameters of earth electrodes and soil structure on current overflow characteristics and grounding performance of earth electrodes, considering self-resistance of earth electrode and parallel-connected multi-point current-injecting mode, a line-current method-based field-circuit coupled model is built. Using the built model, the ground current overflow of DC circular ring earth electrodes is calculated and the earth potential is solved; then through the comparison of measured data with simulation results, the accuracy and feasibility of the proposed model are verified. Research results show that under constant radius of the outer ring the current overflow ability of earth electrodes decrease while the number of circular ring earth electrodes increases and the decreasing extent of grounding resistance alleviates; the current-shunting ratio is approximately proportional to the ratio of inner ring radius to outer ring radius, and with the increase of inner ring radius the shielding effect of outer ring on inner ring intensifies at first and then weakens;when the resistivity of upper layer of soil is less than that of lower layer of soil, along with the increase of the thickness of upper layer of soil the ratio of current-shunting effect of inner ring to that of outer ring decreases at first and then increases, and when the resistivity of upper layer of soil is higher than that of lower layer of soil, along with the increase of the thickness of upper layer of soil the variation trend of the ratio of current-shunting effect of inner ring to that of outer ring is just the opposite; in addition, with the increase of the thickness of upper layer of soil the influence of the resistivity of upper layer of soil on grounding performance intensifies and the influence of the resistivity of lower layer of soil on grounding performance weakens.关键词
高压直流输电/接地极/溢流特性/分流比Key words
HVDC power transmission/earth electrode/current overflow characteristics/current-shunting ratio分类
信息技术与安全科学引用本文复制引用
黄渤,吴广宁,曹晓斌,任志超,张龙伟..高压直流输电接地极溢流特性[J].电网技术,2013,(4):1174-1179,6.基金项目
国家电网公司科技项目(2011-WG-4) （2011-WG-4）
铁道部重大专项课题(2011T008) （2011T008）
中央高校基本科研业务费专项资金(SWJTU11CX035) （SWJTU11CX035）
