非周期分量线路差动保护特殊问题研究

非周期分量线路差动保护具有不受线路对地分布电容影响的突出优点,解决了工频量线路差动保护的难题。对超高压线路上装有并联电抗器和线路一端装有串补电容的情况以及特殊工况进行了分析和仿真,说明非周期分量线路差动保护是正确可靠的。非周期分量差动保护和行波差动保护都存在特定故障时灵敏度不足的问题,但二者在灵敏度问题上正好完全互补,线路非周期分量差动保护与行波差动保护一体化,可以进一步提高线路差动保护的整体性能。

Study on special problems of the line non-periodic current differential protection

The line non - periodic current differential protection has a distinct advantage that is not affected by the line distributed capacitive current to ground,which could solve the puzzle of the line fundamental current differential protection' s performance degradation due to the line distributed capacitive current to ground.Analyzing and simulation indicate that the line non - periodic current differential protection is correct and reliable in special working conditions of power system,including in ultrahigh tension power lines with the shunt reactor or the series- compensated capacitor at one - end.The line non - periodic current differential protection and the line travelling wave current differential protection are both less sensitive but complemented in special accidents,which could be combined to improve performances of the line current differential protection.