智能变电站保护动作时间延时特性研究

Research on characteristics of intelligent substation protection time delay

在智能变电站中,数字化保护所引入的合并单元、智能终端等智能设备延长了保护的动作时间,对电力系统故障的快速切除带来了安全隐患。因此,有必要对智能站中保护动作延时的环节进行深入分析。首先给出了智能站继电保护动作的各个延时组成部分,对比了其与常规站保护动作时间各环节的差异性。对差异环节中的采样延时和智能终端延时这两大主要延时构成部分进行了详细分析,给出了智能站延时现象的深层机理。探讨了降低各延时环节的有效措施。通过实验对比了常规站和智能站各环节动作时间的差异性,验证了理论分析的正确性。

In intelligent substation, the introduction of digital protection devices such as merging unit, intelligent terminal, etc. prolongs the operation time of protection, which brings the safe threat to the cutoff of power system fault. Therefore, it is necessary to analyze the time delay link of protection operating time in intelligent substation. In this paper, the composition of time delay in intelligent substation is given, and the difference of each part between intelligent and traditional substation is analyzed. Further, the two major compositions of time delay in sampling and intelligent terminal link are analyzed in detail, the deep mechanism of time delay phenomenon is given and the effective measures to reduce the time delay in each link are discussed. Finally, the differences of operation time delay between traditional and intelligent substation are compared by experiment, and the results testify the validity of theoretical analysis.