CAJ | 학술논문

行波距离保护中存在对端母线反射波影响测距准确性的问题，为此提出一种新的可以统一识别各种接地故障下第2个反射波性质的方法，并给出实现方案。首先通过相模变换，提取初始行波和第2个反射波的0模分量极性以及3个分别以A、B、C相为基准的1模分量极性。然后将初始行波0模分量和3个1模分量的极性关系与第2个反射波0模分量和3个1模分量极性关系进行比较，如果至少有2组关系相同，则为故障点的反射波；如果最多只有1组关系相同，则为对端母线的反射波。大量仿真表明，该方案能正确识别各种接地故障第2个反射波的性质，且不受两端母线结构的影响。
행파거리보호중존재대단모선반사파영향측거준학성적문제，위차제출일충신적가이통일식별각충접지고장하제2개반사파성질적방법，병급출실현방안。수선통과상모변환，제취초시행파화제2개반사파적0모분량겁성이급3개분별이A、B、C상위기준적1모분량겁성。연후장초시행파0모분량화3개1모분량적겁성관계여제2개반사파0모분량화3개1모분량겁성관계진행비교，여과지소유2조관계상동，칙위고장점적반사파；여과최다지유1조관계상동，칙위대단모선적반사파。대량방진표명，해방안능정학식별각충접지고장제2개반사파적성질，차불수량단모선결구적영향。
In traveling wave based distance protection there is a problem that the reflected wave from opposite busbar affects the accuracy of fault location. Therefore a new method, by which the features of the second reflected wave under various types of earth faults that can be uniformly recognized, is proposed, and corresponding realizing scheme is given. Firstly, through phase-mode transformation the mode-0 component polarities of initial traveling wave and the second reflected wave as well as their three mode-1 polarities taking phase A, phase B and phase C as the benchmark are extracted; then the relationship among polarity of mode-0 component and polarities of three mode-1 components of initial traveling wave is compared with the relationship among polarity of mode-0 component and polarities of three mode-1 components of the second reflected wave, if there are at least two groups possess the same relationship of polarity, the second reflected wave is from the fault point;if there is at most one group possesses the same relationship of polarity, the second reflected wave is from opposite busbar. A lot of simulation results show that the proposed scheme can recognize the features of the second reflected wave due to various types of earth faults, and the recognizations are not affected by busbar structures at both terminals.