基于新型半周期波形正弦特征的励磁涌流判别方法  

Novel theory of identifying inrush current based on half-cycle sine waveform

作　　者：孙洋[1] 黄家栋[1] 

机构地区：[1]华北电力大学,河北保定071003

出　　处：《电力系统保护与控制》2010年第18期54-58,68,共6页Power System Protection and Control

摘　　要：提出一种新型基于波形正弦特征判别变压器励磁涌流的方法,利用变压器励磁涌流和内部故障电流波形特征的不同,即变压器正常运行、内部故障时波形具有正弦函数的性质;而空投时涌流波形包含非周期分量、间断角并具有尖顶波特性。通过对各种情况下波形极值点的快速识别,构造出与之对应的半周期正弦波形,进而定义正弦贴近函数K,通过正弦贴近函数K来区分变压器励磁涌流和内部故障。变压器各种运行情况的动模试验验证了所提方法的可行性和判据的正确性。A novel theory of identifying inrush current and fault current based on the different characteristics of waveform is given. The waveform has the nature of sine function during normal operation of transformer and internal fault, but the magnetizing inrush current possesses fastigium wave characteristic with non-periodic components and intermittent angle during no-load switching, By identifying the extreme point of the waveform in all cases, a corresponding half cycle sine waveform is constructed. Then K function of sine degree of nearness is defined and used to distinguish magnetizing inrush current from fault current of power transformers. Results of dynamic tests show that the proposed method is feasible and correct.

关 键 词：变压器 励磁涌流 故障电流 尖顶波 正弦贴近系数 

分 类 号：TM407[电气工程—电器]