三角形环网中输电线路故障定位新方法

高压电网中的输电线路多数以环网方式运行,为快速确定短路故障点,本文提出一种三角形环网中的故障定位新方法。该方法利用三次样条差值函数从故障信号中提取衰减扰动量,然后利用电压、电流扰动量的峰值识别故障线路,并通过定义输电线路的线衰率来确定短路故障点在三角形环网中的位置。该方法避免了传统方法中因线路参数不准确而产生的定位误差,同时结果不受系统运行方式和过渡电阻的影响。通过两机无穷大系统仿真验证了该方法的正确性和可靠性。仿真结果表明:该方法能准确定位短路故障点的位置;而且所需测量单元的数量少,能够减少大量投资。

A New Fault Location Method for Transmission Line in Triangle Network

Since the majority structure of transmission line is the ring network, a new method for fault location in triangle network is proposed in this paper. This method is based on cubic interpolating polynomial and extraction of transient variable from fault disturbance. The fault line is identified by using the amplitude of voltage disturbance and current disturbance. The location of fault point in triangle network is calculated by the ratio of voltage disturbance on the line. The accuracy of this method is tested and proved by the simulating model with two generators and an infinite system. The results of simulating test show that the location of fault point is calculated very quickly and the needed number of measuring units is so little that huge investment could be reduced.