【摘要】 在分析瞬时功率频谱特性的基础上,提出了一种基于瞬时功率的变压器励磁涌流和内部故障电流识别新方法。该方法主要依据变压器两侧三相差瞬时功率幅频特性中直流分量和基频分量的相对关系来识别变压器励磁涌流和内部故障电流。该方法具有传统变压器电流差动保护简便易行的特点,并从能量守恒的角度出发,进一步揭示了变压器励磁涌流与内部故障电流本质上的不同。HYBRISIM混合仿真实验结果表明该方法简单可靠、识别效果明显。更多还原

【Abstract】 A new method, based on the analysis of frequency spectrum of instantaneous power, for the discrimination between internal fault currents and inrush currents in transformer is proposed. The method distinguishes the two kinds of currents clinging to the relative connection between the DC component and the fundamental frequency component of the differential instantaneous power. It also has the advantages of simpleness and convenience in applications that the conventional current differential protection has. And further it reveals the essential difference between the inrush current and the internal current from the viewpoint of energy conservation law. The results of HYBRISIM tests show that the proposed method is feasible and reliable.更多还原