【摘要】 以支路阻抗矩阵作为小电流接地系统的数学模型,以故障点为边界端口,将小电流接地系统无故障对称部分简化为对称双口网络,通过向双口网络边界端口接入 2组相互独立、结构简单的不对称网络来模拟各种两点异相接地故障,建立了小电流接地系统两点异相接地故障的计算模型。基于线性电路的基本定理和相序参数变换技术,提出了小电流接地系统两点异相接地故障计算的新方法。这种方法无需形成复数节点导纳或阻抗矩阵、可自动适应网络拓扑结构变化、方便计及接地点接触电阻,计算简便,易于计算机实现。更多还原

【Abstract】 Taking branch impedance matrix for mathematical model of small current neutral grounding system and faulty point for boundary ports, the fault-free part of small current neutral grounding system was simplified as a symmetrical double ports network, various arbitrary two points earth faults were simulated by connecting two simple and independent unsymmetrical networks to the above-mentioned boundary ports and corresponding calculation model was built up. Based on the basic theorem of linear circuits and sequence parameter transformation technique, a new calculation method for arbitrary two points grounding faults in small current neutral grounding system was proposed. Not having to constitute the complex nodal admittance or impedance matrix, the proposed method could automatically adapt the change of network’s topological structure, the transition resistance at the grounding point could be conveniently dealt with, the calculation might be simple and convenient and this method could be easy to realize by computer.更多还原