基于数学形态学的发电机定子绕组接地保护的研究

针对常用的发电机定子单相接地保护用于扩大单元接线时不具备选择性的问题,利用数学形态学对信号奇异性的检测功能和滤波特性,提出一种比较故障时机端零序电压和零序电流的突变极性来识别故障的新方法,经大量PSCAD仿真验证该保护方法能有效检测定子单相接地故障和准确判断故障发电机,且与发电机中性点接地方式无关。

Study on Protection of Generator Stator Winding Grounding Fault Based on Morphology

Common stator ground protection for the generator is not selective when it is used for the expansion unit connection. This paper aimed at solving this problem and proposed a new method of fault identification by comparing the polar mutations of zero sequence voltage and zero sequence current using signal singularity detection and filtering features of mathematical morphology. PSCAD simulation results show that this method can detect the single-phase grounding fault of stator winding and determine the fault generator effectively with no relation to generator neutral-point grounding modes.