基于组合权重的蒙特卡洛电压暂降评估方法

A Monte Carlo Assessment Method of Voltage Sags Based on Combination Weight

针对电网中监测装置配备滞后、电压暂降水平亟待评估的问题,提出一种基于组合权重的蒙特卡洛评估方法。评估工作中,着重研究电网中线路短路故障对节点电压的影响。首先在考虑数据易获取性的基础上,构建涵盖线路自身属性及环境因素的故障概率评估体系,结合G1法和熵权法评估线路故障概率。该体系相比传统的评估体系,更加接近电网的真实工况,能够准确反映电网中短路故障的分布情况。运用该评估体系,构建故障数学模型,开发适用的BPA程序计算接口,可以对电网进行蒙特卡洛模拟仿真。研究结果对电网的改造和缓解装置的配备有指导性作用。最后以某特大城市的220 kV电网为例进行电压暂降评估,验证了方法的有效性。

In view of shortage of monitoring devices in voltage sags assessment,this paper presents a Monte Carlo assessment method based on combination weights.Assessment work focuses on impact on node voltage caused by short circuit.Firstly,an indicator system covering power line characteristic and environment effects is established considering easy accessibility of data and using G1 method and entropy method to evaluate failure probability of power lines.Compared with existing one,this indicator system is closer to real conditions of power grid,correctly displaying frequency distribution of short circuit faults.Then an appropriate fault probability model is designed.BPA program is used for Monte Carlo simulation of grid.Research results have certain guiding significance for power grid improvement and mitigation of device installation.Finally,an example analysis of a large city power grid is given to prove effectiveness of this method.