电力系统振荡过程中序分量选相元件动作行为分析

ANALYSIS ON THE OPERATING CHARACTERISTIC OF THE SEQUENCE-COMPONENT FAULT PHASE SELECTOR DURING POWER SWINGS

对超高压输电线路微机保护所用序分量选相原理和防止振荡时误选相所用的不对称故障开放判据进行了较详细的介绍。对于振荡中心和单相接地故障在同一条长输电线路且两者之间有较远距离的情况 ,从不对称故障开放判据和阻抗排除法两个方面分析了造成误选相的原因。理论分析和动模试验都证实了这种误选相现象的存在 。

In the paper, the theory of sequence component fault phase selection and the criterion for the asymmetry fault during the power swing are presented in detail, which are used in EHV microprocessor based transmission line protection. When the swing center lies in the fault line and the center is far from the fault point, the breaker will trip incorrectly. The reasons why the phenomenon may occur are analyzed considering the criterion opening condition for the asymmetry faults and the impedance excluding method. The fault phase selection characteristic is approved from the theory and the dynamic simulation tests. The content explained above is for the improvement of the sequence component phase selector.