一起变压器发展性故障的保护动作分析  

Analysis on the Protective Action of a Transformer Developing Fault

作　　者：冯国东 

机构地区：[1]上海思弘瑞电力控制技术有限公司,上海201108

出　　处：《河南科技》2015年第9期115-118,共4页Henan Science and Technology

摘　　要：针对一起某变电站110k V变压器的发展性故障,通过现场整定的保护定值和故障录波器波形,详细的分析了故障发展过程,并根据差动保护的动作特性和涌流闭锁判据推导出差动保护在本次故障发展各阶段的动作行为。综合分析后指出:由于本次故障发生在低压侧TA附近,属于空充于差动区内三相短路转区内外异名相三相短路再转区外三相短路的复杂性故障。由于转换时间很短,且受励磁涌流闭锁影响,差动保护在此种转换性故障下不动作,最后由高压侧复压过流保护将故障切除。Aiming at one 110 k V transformer developing fault of a substation, analysis on the developing process ofthe fault by the fixed value set in the field and the wave form from fault wave recorder is carried out, and the protec-tion behavior of differential protection in various developing stages of this fault according to the differential protectionoperation characteristics and inrush blocking criterion is deduced. It is pointed out after comprehensive analysis：asthe occurrence of the fault closing to low-voltage side TA,it belongs to complex faul tranging from three-phaseshort-circuit inside differential protection to three-phase short-circuit inside and outside differential protection andthen to three-phase short-circuit outside differential protection. Due to the short conversion time and influences of in-rush blocking criterion,the differential protection cannot act under this kind of converting fault, at last the fault wasremoved by the compound-voltage over-current protection.

关 键 词：差动保护 发展性故障 区内外三相短路 涌流闭锁 复压过流保护. 

分 类 号：TM774[电气工程—电力系统及自动化]