变压器差动保护误动原因分析及对策综述

Review on Analysis and Strategy for Transformer Differential Protection Malfunction

从理论联系实际的角度综述分析了引起变压器差动保护误动的一些主要原因,包括变压器空载合闸励磁涌流、相邻变压器空投引起的和应涌流、外部故障切除恢复性涌流;电流互感器(TA)暂态饱和、局部暂态饱和;变压器零序涌流助增对变压器差动保护的影响等,根据这些误动原因提出了相应的解决对策。正确地认识和理解这些问题,有助于引起研发、设计、调试、运行等部门的重视,并通过适当的措施来避免这些原因引起的误动,提高变压器保护在现场运行的动作准确率。

The reasons of some typical transformer differential protection malfunction, such as excitation inrush current of transformer no-load closing, sympathetic inrush of energized transformer, restorative inrush caused by external fault cleared, TA transient saturation, partial transient saturation, and assistant of zero-sequence circulation current are theoretically and practically reviewed in this paper. Based on the analysis, some strategies are proposed to avoid these malfunctions. Understanding these problems correctly is helpful in developing, designing, debugging and operating protection device, which will improve the accuracy of transformer protection during field operation.