特高压带并联电抗器线路的行波差动保护

传统的行波差动保护无法应用于带并联电抗器特/超高压输电线路，为此给出了一种新的行波差流表达式，并据此提出一种具有轻微比例制动特性的行波差动保护实用方案。该方案能够有效地躲过各种运行工况和区外故障引起的暂态不平衡差流，同时在区内高阻故障时能够保持很高的灵敏度。理论及EMTP仿真计算表明：该方法灵敏度高，动作速度快，对装置采样和通讯速率没有过高的要求，能够在现有技术条件下实现，具有较高的实用价值。

Traveling-wave Differential Protection on UHV Transmission Line with Shunt Reactor

The traditional traveling-wave differential protection cannot be applied to ultra/extra high voltage transmission line with shunt reactor, so this paper describes a novel differential current expression. Based on traveling-wave differential protection a new scheme with low proportional restraint characteristic is presented. This scheme can avoid transient unbalance differential currents under different operation conditions. It also has high sensitivity for internal high-resistance fault. Theoretical analysis and EMTP simulation show that the scheme operates sensitively and rapidly. The protection has no special demands for sampling rate and communication speed and can be realized by existing technique.