输电线路复故障情况下选相元件研究

首先分析了复故障情况下几种典型选相元件动作行为,然后结合分析结果给出了复故障情况下正确选相元件的整体方案:自适应采用电流量、电压量选相元件,在复故障情况下,利用电压选相元件的结果,通过两故障相分别与健全相构成的工频变化量方向元件来进一步区分区内故障相。基于中国电力科学研究院对于高压输电线路保护装置的检测模型,给出了此方案的RTDS试验结果,理论及大量的试验表明了此选相方案的有效性。

Study of Faulted Phase Selector Element for Duplicate Faults of Transmission Lines

The action of several typical selectors under duplicate fault conditions is analyzed. And a novel selector for duplicate fault condition is presented which adaptively uses current quantities and voltage quantities. Under duplicate fault conditions, the selector presented distinguishes further the in-zone faulted phase by the directional relays respectively using one of the faulted phases from the result of voltage selector and the healthy phase. In terms of the test modes for high voltage protection devices in CEPRI, lots of tests are done using RTDS (real-time digital simulation). Theoretical analysis and test results show that the novel faulted phase selector is correct and reliable.