继电保护运行整定中计算分支系数的快速方法

Fast calculation on branch coefficient in protection relay setting and coordination

目前电力系统继电保护整定计算软件中计算分支系数的常用方法是进行不同运行方式的故障计算,得到保护支路和配合支路的电流,从而得到分支系数。为了提高继电保护运行整定的速度和效率,根据序电流的分布只取决于该序网的结构而与其他序网无关,推导出了一种仅与序网的节点阻抗矩阵有关无需故障电流计算的分支系数的快速计算方法,并针对影响分支系数的不同因素介绍了一些加快措施。编程实践证明,该方法大大提高了继电保护运行整定的速度和效率。

At present, general method to calculate branch coefficient needs fault calculation in different operation modes to get protective branch current and mating branch current. According to sequence current distribution only depending on the sequence network topology, this paper presents fast method to calculate branch coefficient with elements in node impedance matrix, which doesn't need fault calculation and is only concerned with sequence network topology. And against different elements influencing branch coefficient, some accelerating measures are proposed. It proved to be a marked improvement on calculation speed and efficiency of protection setting and coordination by a numerical example.