带串联补偿装置的输电线路距离保护新方案

文章分析了串补设备对距离保护的影响，针对串补设备容易引起距离保护超越误动的问题，将串补电容作为保护线路的边界，提出一种基于正序故障电压分量和直流分量—工频分量百分比的串补线路距离保护新方案。该方案利用串补电容两侧正序故障电压分量的大小来判断串补电容背侧区外故障和区内故障，利用串补电容对侧母线处电流的直流分量与工频分量的百分比来判断区内故障和正向区外故障。经PSCAD仿真验证，该方案可有效提高保护动作的可靠性。

A new distance protection scheme for transmission lines with series compensation equipment

This article first analyzed the influence of series compensation equipment on distance protection.Aiming at the problem that series compensation equipment can easily cause distance protection to exceed the malfunction，the series compensation capacitor is used as the boundary of the protection circuit，and a method based on positive sequence fault voltage component and DC component New distance protection scheme for series compensation line based on percentage of power frequency component.This scheme uses the magnitude of the positive sequence fault voltage components on both sides of the series compensation capacitor to determine the out-of-area faults and the internal faults on the back side of the series compensation capacitor，and uses the percentage of the DC component and the power frequency component of the current at the bus on the opposite side of the series compensation capacitor to judge In-zone fault and forward out-of-zone fault.After PSCAD simulation verification，this scheme effectively improves the reliability of the protection action.