海上风电机组不同基础自然接地体的比较研究

Comparative Study on Using Foundation as Natural Grounding Electrode of Offshore Wind Turbine

海上风力发电机组接地网结构、所处环境等与陆上风力发电机组有显著差异。为研究海上风电机组基础作为自然接地体的问题,分别建立了单桩基础、单柱三钢桩基础、高桩承台基础和导管架基础4种地网形式的计算模型,将模型的每一个导体进行分段,再通过复镜像法求解每一段导体的格林函数,最后通过叠加定理求解基础的接地阻抗,并综合分析了典型水位变化对接地阻抗的影响。结果表明,利用海上风力发电机基础作为自然接地体能够满足电气工程生产和安全的需要,可为海上风电机组接地设计提供参考。

There are a lot of difference between the offshore wind power grounding structure and onshore grounding structure.In order to study the feasibility of using foundation as natural grounding,this paper established simulation model based on the real single pile foundation,three steel pile foundation,high pile cap foundation and jacket foundation.Each conduct in the model was divided into small segments.And then the complex image method was used to solve each segment＇s Green＇s function.Finally,the grounding resistance was obtained by means of superposition principle.The impact of typical water level variation on the grounding impedance was analyzed.The results show that using foundation as natural grounding can meet the need of production and safety of electrical engineering,which can provide reference for offshore wind power grounding design.