考虑故障电阻随机不确定性的电压暂降监测点优化配置

Optimal Voltage Sag Monitors Placement Considering Randomness of Fault Resistance

电力系统元件发生短路故障时,故障电阻客观存在且具有随机不确定特性。为提高电压暂降监测点配置方案在不同故障电阻条件下的工程适用性,需将故障电阻这一关键参数引入到监测点优化配置模型中。首先基于网络参数和短路计算构建临界故障电阻矩阵,在此基础上以监测点数最少为目标,以各故障点短路时最小电压暂降可观率为约束,建立考虑故障电阻随机不确定性的监测点优化配置模型,并用遗传算法求解最优配置方案。应用该方法对IEEE 30节点测试系统进行了仿真分析,结果表明该方法能有效监测非金属性短路故障引起的电压暂降,相比传统方法更具工程实用价值。

When short-circuit fault occurs in a power system,fault resistance frequently existed,and the value of the fault resistance is random due to many factors. In order to effectively monitor voltage sags in the whole network,the variable of fault resistance should be added into optimal model. In the proposed method,matrix of critical fault resistance is established based on the parameters of power network and short circuit calculation,then optimal placement model considering randomness of fault resistances can be built. The constraint in the improved model is the observability rate of voltage sags,and the objective is to minimize the number of monitors placed in the whole network. Based on the optimal model, genetic algorithm is applied to obtain the best placement scheme. The proposed method has been applied to the IEEE 30-bus test system,simulation results show that,voltage sags caused by short-circuits resistances can be effectively monitored based on the improved method. Compared with traditional method,the proposed method can be more applicable in practical engineering.