导纳互差之绝对值和的极大值法小电流接地选线研究

在详细分析了小电流接地电网零序测量导纳分布的基础上，提出了一种新的小电流接地选线方法——导纳互差之绝对值和的极大值法。该方法有效地拉大了故障馈线与非故障馈线故障判断量的差距，极大地提高了保护裕度。由于该方法所用的故障判断信息大，使其抗干扰能力大为增加。运行情况证明，该方法有效地提高了小电流接地选线的准确性。

STUDY ON EARTHED FAULT LOCATION METHOD IN INDIRECTLY GROUNDING POWER SYSTEM USING MAXIMUM VALUE OF ABSOLUTE VALUE SUMMATION OF MEASUREMENT ADMITTANCE MUTUAL DIFFERENCE

Based analysis of the zero sequence measurement admittance distribution in the indirectly earthed power system, a new detecting fault feeder method in the indirectly earthed power system, i.e. a maximum value method of the absolute value summation of the measurement admittance mutual difference, is proposed. This method increased effectively the difference of the fault judging quantity in fault feeder and non-fault feeder, and the protecting abundant degree has been also greatly enhanced. The anti-interference capability of this method can be greatly increased because the method uses a great amount of the fault judging information. The operation results of the power system indicated that this method has effectively raised the accuracy of the detecting fault feeder method in indirectly earthed power system.