摘要
为完善直流输电线路的保护系统,以高压直流输电系统暂态过程为研究对象,采用PSCAD分别建立了高压直流输电系统(包括线路、杆塔、绝缘子串等)落雷闪络模型和直流输电系统模型;仿真了线路不同位置遭受雷击情况对直流输电系统的影响,直流线路保护区内外发生典型故障、双极运行模式下故障极对健全极的影响等多个暂态过程;利用小波变换进行信号分解分析,寻找出能够表征线路落雷导致系统故障或不致系统故障的明显暂态特点,分析能够体现不同类型故障的特征信号以及双极运行工况下,消除故障极对非故障极干扰的措施等问题。结果表明,上述研究对高压直流输电的安全控制与保护系统的可靠运行具有重要现实意义。
In order to perfect the protection system of HVDC transmission line, and to study electromagnetic tran- sient process for HVDC （High Voltage Direct Current） transmission system, the lightning stroke flashover model and HVDC transmission system model are built by adopting PSCAD/EMTDC, in which the lightning stroke flashover model include transmission line, transmission tower, insula- tor string etc. Transient processes, such as the effect of lightning stroke at different positions on HVDC system, the typical fault occurring in both internal and external protec- tion section of HVDC system, the influence of fault elec- trode on health electrode in the mode of two electrodes, are simulated. The decomposition analysis of signals are carried out by wavelet transform, and the different transient char- acteristics showing whether lightning stroke results in faults or not is found out. In addition, the characteristic signalsthat can represent different types of faults are analyzed, and the measures to avoid the interference of faulty electrode on non-faulty electrode for the operation mode of two elec- trodes are given. The results show that the study on electro- magnetic transient process has important practical signifi- cance for the operation reliability of protection system and the securitv control of HVDC transmission line.
出处
《现代电力》
2011年第6期23-28,共6页
Modern Electric Power
基金
山东省电力集团公司项目(高压直流输电线路新型差动保护算法配置及控制方案研究)
关键词
电磁暂态
雷击闪络
小波变换
暂态信号
电压变化量
高压直流
electromagnetic transient lightning strokeflashover wavelet transform transient signal
voltage vari-ation~ HVDC
