中文说明：
本程序是用节点导纳矩阵计算三相短路电流 输入数据--形成节点阻抗矩阵--选择故障点---计算短路电流----计算个节点电压---计算指定支路的电流
English Description：
This procedure is to use the node admittance matrix calculation of three-phase short-circuit current _ - form the node impedance matrix - select input data point of failure - calculation of short-circuit current node voltage - - to calculate the designated branch of the current