220kV电网保护死区动作分析与改进

Analysis and Improved Design for Protection's Dead-zone of 220kV Grid

随着电网结构愈来愈复杂,电力系统安全稳定运行越来越重要。电网保护死区故障时由后备保护动作,隔离故障点时间长,不利于电网安全。本文分析了地区电网220k V变电站高压侧几种常见的保护死区故障及逻辑问题,结合现有电网典型保护死区的继电保护方案,根据保护死区的故障特点,提出封故障间隔开关CT构成死区故障的快速保护方案。该方案可有效地提高继电保护装置的可靠性和电网运行的稳定性。

As the grid structure become more and more complicated, the problem of safe and stable operation of power system becomes increasingly prominent. Backup protection operates when failure occurs in the dead zone, which is unfavorable for grid security because of long time action. This paper analyzes several common failures in dead zone and logic problems in regional power grid, and then introduces some typical relay protection schemes about dead zone protection at present, finally put forward that the CT is connected to constitute a fast protection for Dead-zone fault, which can effectively improve the reliability of relay protection device and the stability of power grid operation.