基于正序分量的变压器励磁涌流新判据  

New criterion of transformer magnetizing inrush current based on positive sequence component

作　　者：金恩淑[1] 李晓娜[1] 夏国武[2] 宋晓刚[1] 刘聪[1] 苏东波[1] 

机构地区：[1]东北电力大学电气工程学院,吉林吉林132012 [2]通辽电业局,内蒙古通辽028000

出　　处：《电力系统保护与控制》2012年第23期7-11,共5页Power System Protection and Control

摘　　要：基于二次谐波制动原理的变压器差动保护在应用过程中误动的情况时有发生。鉴于序分量作为电气量被应用于继电保护的实际情况,分析了差流二、三次谐波正序分量在变压器内部故障和励磁涌流时的不同特征,分别分析了当CT未饱和、轻度饱和以及严重饱和时的情况,进而提出一种基于差流正序分量的励磁涌流新判据。通过大量仿真,表明该算法简单易行,能有效防止空载合闸时差动保护误动,而且当CT畸变严重时仍然有效,同时,在内部故障时能够可靠并快速动作。The mal-operation of the transformer differential protection based on second harmonic restraint principle takes place occasionally. In view of the fact that sequence component as electrical quantities is applied to relay protection, positive sequence component of the second and third harmonic differential current is analyzed respectively in the case of transformer internal faults and magnetizing inrush current, as well as when CT is unsaturated and CT saturation is mild or severe respectively. According to the different characteristics in case of internal faults and magnetizing inrush current, a new criterion based on the positive sequence component of the differential current to identify in the magnetizing inrush current is proposed. A large number of simulations show that the new criterion is simple and easy to put into practice, and it is effective to prevent malfunction in the situation of no-load closing, as well as when CT distortion is severe, besides, it can trip reliably and timely as internal fault occurs.

关 键 词：变压器 励磁涌流 CT饱和 谐波 正序分量 

分 类 号：TM407[电气工程—电器]