海上风电场电缆-架空线输电系统雷击过电压暂态分析

Transient Analysis of Lightning Overvoltage of Cable-Overhead Line Transmission System in Offshore Wind Farm

为了研究大型海上风电场海底电缆-架空线输电系统雷击过电压的问题,在充分研究输电系统结构的基础上,使用PSCAD/EMTDC仿真软件搭建暂态计算模型。考虑工频电压对雷击过电压的影响,重点研究分析了电缆长度、杆塔接地电阻、雷击距离、雷电流幅值等因素对暂态过电压的影响及其原因。仿真结果和分析表明:杆塔接地电阻和雷电流幅值的增大、雷击距离和电缆长度的减小会导致雷击过电压的增大。考虑避雷器的优化配置,能有效抑制海底电缆首末两端的过电压幅值,相关结论为海上风电场电气系统的防雷绝缘设计提供了一定参考。

In order to study the lightning overvoltage problems of the submarine cable-overhead power transmission system in large offshore wind farm, based on fully research the transmission system structure, PSCAD / EMTDC simulation software is used to build a transient calculation model. Consider- ing the effects of power frequency voltage on lightning overvoltage, we focus on analyzing the length of ca- ble, tower grounding resistance, the distance from the lightning, lightning current amplitude of transient overvohage. The simulation results and analysis show that the increase of the grounding resistance and the lightning current amplitude, the decrease of the distance and the length of the cable can lead to the in- crease of the lightning overvoltage. Considering the optimized configuration of the lightning arrester, we can reduce the overvoltage amplitude of the submarine cable at both ends, the relevant conclusions for the offshore wind farm electrical system design provides a certain reference for the lightning protection.