CAJ | 학술논문

为提高行波方向元件的可靠性，在分析故障方向特征的基础上，提出一种新的幅值比较式方向元件。不同故障方向下，前行波和反行波特征不同。正方向时前行波和反行波差异较小，反方向时两者差异较大。利用 S 变换能量相对熵量化前、反行波之间的差异程度。考虑到电容式电压互感器(CVT)不能传变较高频率的电压分量，对前、反行波进行 S 变换后选择较低频率的分量计算能量相对熵，进而构成方向判据。基于 PSCAD/EMTDC 的仿真结果表明，所提方向元件能够快速可靠地判断故障方向，其性能不受故障初始角、过渡电阻、故障位置、故障类型、母线接线方式和电弧故障的影响。
위제고행파방향원건적가고성，재분석고장방향특정적기출상，제출일충신적폭치비교식방향원건。불동고장방향하，전행파화반행파특정불동。정방향시전행파화반행파차이교소，반방향시량자차이교대。이용 S 변환능량상대적양화전、반행파지간적차이정도。고필도전용식전압호감기(CVT)불능전변교고빈솔적전압분량，대전、반행파진행 S 변환후선택교저빈솔적분량계산능량상대적，진이구성방향판거。기우 PSCAD/EMTDC 적방진결과표명，소제방향원건능구쾌속가고지판단고장방향，기성능불수고장초시각、과도전조、고장위치、고장류형、모선접선방식화전호고장적영향。
On the basis of analyzing the fault direction characteristics, a novel directional element based on amplitude comparison is proposed.The characteristics of the forward wave and backward wave are different in different directions.The difference between the forward wave and the backward wave is rather small under a forward fault while the difference is large under a backward fault.S-transform energy relative entropy is utilized to quantize the difference.In consideration of the inability of the capacitor voltage transducer (CVT), to transform high frequency voltage signals, the lower frequency component is made use of to calculate the energy relative entropy.Then the criterion for fault direction is established.The simulation results based on PSCAD/EMTDC indicate that the proposed directional element is reliable and rapid and its performance is not affected by the fault inception angle,fault resistance,fault position,fault type and busbar configuration, and the arc fault. This work is supported by National High Technology Research and Development Program of China (863 Program) (No.2012AA050208),National Natural Science Foundation of China (No.5 1307145) and Fundamental Research Funds for the Central Universities (No.SWJTU1 1ZT07).