抑制直流偏磁的直流接地极综合优选策略

Study on the Site Optimization of DC Grounding Pole to Depress the Effect of DC Bias

接地极是直流输电系统发生直流偏磁现象时构成导线大地回路的重要组成部分,在直流偏磁风险和严重程度日益提升的情况下,合适的选址将显著有助于直流偏磁的治理。为此,提出一种计及直流偏磁综合治理效果的接地极选址方案评估及优选策略研究。新策略选取治理效果、投资成本、环境影响以及未来电网适应性作为综合评估指标,并建立基于上述指标的合理评估模型,采用基于相对熵的组合赋权法进行赋权排序,最终选出最优选址方案。新策略综合考虑多种因素的影响,使得选址结果更全面、合理。此外,所采用的组合赋权法分别从主观和客观两方面进行定性分析与定量计算,避免单一赋权法的局限性。最后以宜昌电网为例,仿真验证所提策略的有效性及可靠性。

The grounding electrode is an important part of the conductor earth circuit when DC bias occurs in the DC transmission system. In the case of increasing risk and severity of DC bias, the suitable site selection will significantly contribute to the suppression of DC bias. This paper presented an evaluation and optimization strategy for the selection of the grounding electrode considering the effect of DC bias. the suppression effect, investment cost, environmental impact and AC topology adaptability was taken into account as evaluation indicators, adopted the relative entropy-based combination weighting method for weight ranking, and finally selected the optimal site scheme. The new strategy comprehensively considers the influence of many factors, making the results more comprehensive and reasonable. In addition, the combined weighting method uses qualitative and quantitative calculations from both subjective and objective aspects, avoiding the limitations of the single weighting method. Finally, Yichang Power Grid was taken as an example to verify the effectiveness and reliability of the proposed method.