一起220kV变压器比率差动动作实例分析

An Example for Analysis the Action of 220 kV Transformer Percentage Restraint Differential Protection

某220 kV变电站发生一起变压器比率制动差动保护动作事件。经过现场设备排查及对各微机保护装置的录波、采样文件进行对比和分析,模拟实际故障仿真计算,认定为是一起主变压器区内外同时发生故障的事故。由于此种类型的一次设备故障比较少见,在对保护装置动作行为进行初步分析时,容易得出变压器差动保护误动作的结论。通过对本次继电保护动作排查、分析,查明了故障原因,得出两套保护装置虽然动作不一致却均是正确动作的结论,对继电保护工作者进行故障分析提供借鉴作用。

An example of transformer percentage restraint differential protection happende in 220 kV substation. After the scene investigation and the wave recording of relevant microcomputer protection devices, sampling file comparison and analysis and simulating the actual failure simulation, it is determined that an accident occurred in the internal and external faults of transformer at the same time. Because this type of the primary equipment failure is seldom, it is easy to draw a conclusion of maloperation of transformer differential protection before acting analysis of protection devices. Based on the protective actions of this investigation and analysis, it comes to the conclusion of two protective devices correct operation after identify the cause of the failure though protection behavior inconsis- tent. I hope this article can provide a reference function to fault analysis for relay protection researchers.