基于区间数理论的电能质量综合评估模型

A comprehensive power quality evaluation model based on interval number theory

将电能质量评价标准作为一个区间数概念处理,提出了基于区间数理论的电能质量综合评估模型。根据原始指标权重值范围,利用线性目标规划模型得出主观权重,利用改进拉开档次法得出客观权重,基于加法原理确定各指标的综合权重。引入多目标决策理想区间法计算待评样本各指标值与理想区间的距离。取各距离的倒数值且进行归一化处理后,作为样本与电能质量评价标准模式的贴近度,实现电能质量的综合评估。该方法既能够对电能质量进行整体评估又可以对同一等级的电能质量进行精细的评价。实际算例验证了该模型的有效性和可行性。

According to the interval number concept of assessment standard of power quality, a new synthetic power quality evaluation model based on interval number theory is proposed. Based on the original indexes weight range, the subjective weighting is obtained using the linear goal programming model, and the objective weighting is obtained using the improved scatter degree, then the comprehensive weighting could be determined based on addition principle. On this basis, a multiple objective decision-making ideal interval method is introduced to calculate the distance between indexes data of the sample and ideal interval. The approach degree between the sample data and power quality standard mode is defined by using the normalized reciprocal of the distance, thus the comprehensive evaluation of power quality is achieved. This method not only can perform comprehensive assessment, but also can evaluate power quality difference more precisely within the same power quality grade. The feasibility and validity of the proposed model are demonstrated with the results of the practical example.