电网技术Issue(10)：2719-2725,7.
基于小波分析的特高压直流输电线路双端电压暂态保护
Wavelet Analysis Based Two-Terminal Transient Voltage Protection for UHVDC Transmission Lines
摘要
Abstract
The frequency characteristics of UHVDC transmission line from Yunnan to Guangdong as well as those at the boundaries of the project are analyzed, and analysis results show that when the distance between the fault point and the position where the protection device is installed exceeds a certain length, the signal of a certain high frequency will be more attenuated by transmission line than by local boundary where the protection device is installed, on this basis, a transient protection principle for UHVDC transmission line, in which the fault that occurs inside or outside the protection zone at the opposite terminal is distinguished by protective element, is proposed. Results of analysis and simulation show that using the proposed protection principle the full length of the transmission line can be protected. By means of comparing the transient fault signal detected at both terminals, it can be judged that the fault point is closer to rectifier side or to inverter side; applying multi-scale wavelet transform to the detected fault transient voltage signal at opposite terminal, using the difference between wavelet energy in high-frequency section and that in low-frequency section the criterion to distinguish the fault occurred inside protection zone from the fault occurred outside protection zone can be constructed;according to the difference between post-fault transient voltages of both DC polar lines, a criterion for fault pole selection can be constructed. PSCAD based simulation results show that the proposed method can reflect transition resistance well.关键词
双端电压暂态保护/特高压直流/高频衰减/小波分析/故障选极Key words
two-terminal transient voltage protection/UHVDC transmission line/high frequency attenuation/wavelet analysis/fault pole selection分类
信息技术与安全科学引用本文复制引用
陈仕龙,张杰,毕贵红,谢佳伟,束洪春..基于小波分析的特高压直流输电线路双端电压暂态保护[J].电网技术,2013,(10):2719-2725,7.基金项目
国家自然科学基金项目(51267008)。@@@@Project Supported by National Natural Science Foundation of China(NSFC)(51267008) （51267008）
