基于可变模糊集的电能质量评估方法

Power quality assessment method based on variable fuzzy set

针对轧机系统工况对电网电能质量的影响,提出一种基于可变模糊集的电能质量评估方法,该方法采用可变模糊集原理对轧机系统3种工况的电能质量进行综合评估.根据国家标准确定各指标的标准值区间矩阵以及可变范围评估区间矩阵,基于标准值区间矩阵建立隶属度等于1的点值矩阵并计算指标的相对隶属度,进而计算轧机不同工况下电能质量的综合隶属度.采用最优组合权重法为指标赋权,使指标权重的赋值更贴近轧机的实际工况.某钢铁厂10kV段轧机系统电能质量评估结果表明该方法具有可行性.

Aiming at the influence of different working conditions of rolling mill system on power quality of power grid,a method of power quality evaluation based on variable fuzzy sets was proposed.The method used variable fuzzy sets theory to comprehensively evaluate the power quality of three working conditions of rolling mill system.According to the national standard,the standard value interval matrix and the variable range evaluation interval matrix of each index were determined.Based on the standard value interval matrix,the point value matrix with membership degree equal to 1 was established and the relative membership degree of each index was calculated,and then the comprehensive membership degree of power quality under different conditions of rolling mill was calculated.The optimal combination weight method was selected to assign weight to each index,so that the assignment of weight to each index was closer to the actual working condition of rolling mill.The evaluation results of power quality of a 10 kV rolling mill system in an iron and steel plant showed that the method was feasible.