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-this procedure is used node admittance matrix calculation of three-phase short-circuit current input data -- forming node impedance matrix -- election Optional fault --- calc