基于波形系数的自适应距离保护

为了描述非全波波形畸变程度,提出了波形系数的概念。仿真显示,波形系数与电气量幅值误差有明确的关系。针对目前快速距离保护采用的保护范围反时限特性具有保护范围的开放很保守、不能保证远端故障的快速切除等缺陷,提出了基于波形系数的自适应距离保护方案。故障发生后,实时计算波形系数,并根据波形系数自适应地调整保护的整定值,使保护更好地适应系统的故障状况,而不再采用按时限逐步开放保护范围的做法。

Adaptive Distance Protection Based on Waveform Factor

This paper proposes a new concept called waveform factor, which can describe the distortion degree of optional data-window. Simulation results show there is a definite relationship between waveform factor and amplitude error. At present, the inverse-time characteristic of zone I distance relay has some defects such as conservative protection domain and long time delay when the fault is at the end of the protected line. To repair these defects, this paper presents an adaptive protective relaying scheme for high-speed distance protection. The scheme adjusts distance relay's setting value based on the waveform factor of fault current. When fault occurs, zone I distance relay calculates the waveform factor of fault current in real-time and adjusts its setting value according to the waveform factor, no longer adopting the inverse-time characteristic.