摘要
分析了Yn/Y变压器微机差动保护在保护区外发生单相接地短路故障时,由于零序电流的存在将使变压器差动保护可能出现误动。用不对称理论对单相接地短路故障各序电流进行分析,得出变压器差动保护区外误动原因并提出防误动的措施。验证了变压器差动保护区内单相接地短路故障时单侧电源与双侧电源的变压器差动保护的灵敏度。
Because of the existence of zero sequence current, the transformer differential protection may function improperly when the single-phase grounding short circuit fault happens outside the microcomputer based transformer differential protection area. The asymmetry theory is used in this paper to analyze every sequence current with single-phase grounding fault, and the cause of out-area malfuntion of transformer differential protection is analyzed and the measure to prevent the malfunction is also put forward. This paper also verifies the sensitivity of the transformer differential protection with unilateral power and bilateral power when the in-area single-phase grounding short circuit fault happens.
出处
《水电能源科学》
2008年第6期165-167,174,共4页
Water Resources and Power
关键词
微机差动保护
单相接地故障
补偿方式
比率制动特性
microcomputer differential protection
single-phase grounding fault
compensation method
ratio-restrained characteristic
