±800kV锦苏直流工程全压启动故障仿真分析

Simulation and Analysis on Full-voltage Starting Faults in ±800 kV Jinping-Suzhou UHVDC Projectct

特高压直流系统出现全压启动故障时会在线路和直流母线设备上产生很高过电压,威胁设备和系统的运行安全。文中运用PSCAD/EMTDC电磁暂态仿真软件建立了±800 k V锦屏-苏州特高压直流工程全压启动故障计算模型,仿真计算了该工程在金属回线、单极大地回线和双极大地回线3种运行方式下出现全压启动故障时引发的过电压、过电流,分析了其波形与幅值,核算了此时设备的绝缘裕度是否满足要求。计算结果表明,在当前的避雷器配置下,锦苏特高压直流工程出现全压启动故障时的过电压最高达到1 398.5 k V,低于设备1600 k V的绝缘水平且满足10%的绝缘裕度要求。文中的研究成果可为特高压直流工程的设计、运行和维护提供参考。

A full-voltage starting fault in the UHVDC system may cause very high over-voltage on transmission line and other equipment. The over-voltage threatens the safe operation of DC power equipment and system. In this paper, the overvoltage simulation model of ±800 k V Jinping-Suzhou HVDC project is constructed in PSCAD/EMTDC. The over-voltage and over-current caused by full-voltage starting faults under three operation modes in this project are computed. The amplitudes and waves of over-voltage are analyzed and the insulation margins of the equipment are checked. The results show that the highest amplitude of the over-voltage is 1 398.5 k V when full-voltage starting fault occurred in the current arrester configuration in ±800 k V Jinping-Suzhou HVDC project, which meets the requirements of insulation coordination. This study provides a reference for the design, operation and maintenance of UHVDC projects.