基于随机预估和模糊评判的电压暂降风险评估  

Risk Assessment of Voltage Sag Based on Random Prediction and Fuzzy Evaluation

作　　者：邱知 刘晓波[1] 韩祥民 徐邦贤 唐辉 史华亮 QIU Zhi;LIU Xiaobo;HAN Xiangmin;XU Bangxian;TANG Hui;SHI Hualiang(The Electrical Engineering College,Guizhou University,Guiyang 550025,China;School of Electrical Engineering,Yanshan University,Qinhuangdao,066000,China)

机构地区：[1]贵州大学电气工程学院,贵州贵阳550025 [2]燕山大学电气工程学院,河北秦皇岛066000

出　　处：《电力科学与工程》2021年第10期36-44,共9页Electric Power Science and Engineering

基　　金：国家自然科学基金(51867005)。

摘　　要：在电压暂降发生时,电压暂降起始点和相位跳变的测量难以在实测中实现,给基于实测法的电压暂降评估带来了阻碍,而且在传统的电压暂降评估中也忽略了这两个特征量。针对这一缺陷,提出了一种基于随机预估和模糊评判的电压暂降风险评估方法。首先,对线路故障概率评估方法和系统短路故障模型进行了改进;然后,结合该方法和模型,在PSCAD/EMTDC平台构建IEEE-14节点系统模型进行了仿真计算,得出系统每个节点在每次仿真中的电压暂降幅值、电压暂降持续时间、电压暂降起始点和相位跳变这4个特征量数据,并考虑将电压等级在内的5个影响因素依据各自的影响度区间进行严重程度等级划分,根据划分结果和仿真数据通过模糊统计法得出各节点各指标对评价等级的隶属度;最后,通过模糊运算得出电压暂降风险评估结果。评估结果表明了该评估方法的科学性和有效性。When the voltage sag occurs,the measurement of the voltage sag starting point and phase jump is difficult to achieve in actual measurement,which brings obstacles to the voltage sag evaluation based on the actual measurement method,and these two characteristic quantities are also ignored in the traditional voltage sag evaluation.Aiming at solving this problem,a voltage sag risk assessment method based on random estimation and fuzzy judgment was proposed.Firstly,the line fault probability assessment method and system short-circuit fault model were improved.Secondly,combined with this method and model,an IEEE-14 node system model was constructed on the PSCAD/EMTDC platform and simulation calculations were carried out.It is concluded that each node of the system had the four characteristic data of voltage sag amplitude,voltage sag duration,voltage sag starting point and phase jump in each simulation,and considering the five influencing factors including voltage level according to their respective influence levels,the interval was divided into severity levels.According to the division results and simulation data,the membership degree of each index of each node to the evaluation level was obtained through the fuzzy statistics method.Finally,the voltage sag risk evaluation result was obtained through the fuzzy operation and the evaluation result indicated the assessment method is scientific and validity.

关 键 词：电压暂降 随机预估 概率模型 模糊统计 模糊评判 

分 类 号：TM7[电气工程—电力系统及自动化]