变电站接地网故障诊断的节点电压线性优化模型

Nodal Voltage Linear Optimization Model for Fault Diagnosis of Grounding Grid in Substations

变电站接地网是电力系统的重要组成部分,是确保变电站运行人员及电气设备安全的重要措施。接地网故障诊断可以为电力运行部门提供十分重要的信息。提出了一种适用于变电站接地网故障诊断的节电电压线性优化模型,首先通过建立接地网的原始网络和故障网络,将网络故障前后支路电阻的变化量表示为可测节点到参考点路径上支路电阻电压电流间的线性关系,在此基础上建立线性最小二乘优化模型,给出了基于原始网络参数的迭代算法。该模型简单,算法速度快,收敛性能好。通过实例仿真证明该方法是接地网故障诊断的有效方法。

Grounding grid of substation is a very important part of power system and is a very important means to ensure the safety of personals and equipment. Fault diagnosis of grounding grid can provide meaningful information to operational departments of power industry. This paper proposes nodal voltage linear optimization model for fault diagnosis of grounding grid in substations. Firstly,the resistance variations between the original network and faulted network of grounding grid are expressed as linear combinations of voltage and currents of resistance along the path from the measuring node to reference node. Then a linear least square optimization model is presented. An iteration algorithm is proposed which starts from the resistance value of the original network. The presented model is simple,has high computation speed and rapid convergence. The results of simulation show that it is an effective method for fault diagnosis of grounding grid in substation.