用模糊贴近度识别变压器故障电流和励磁涌流的研究

Identify the Fault Currents and Inrush Current of a Transformer Using the Fuzzy Degree of Nearness

提出了用波形对称及模糊集贴近度原理来辨识故障电流和励磁涌流的新方法。数字仿真及实验结果表明：本方法可准确识别故障电流和励磁涌流；即使在空载合闸于内部短路故障时，保护继电器也能迅速可靠动作，避免了采用二次谐波制动导致的拒动问题。

In the paper presented a new algorithem of using the fuzzy degree of nearness combined with the symmetries of wave forms to identify the fault currents and inrush current of a power transformer.The results have been showed that the method can identify both the fault currents and inrush current precisily and make it rapid and reliable for the protective relay to trip even if switching on under noload conditions with an internal fualt.