将电能质量进行综合评估得出的量化结果,是衡量电能质量优劣的依据之一,有利于实现电能按质定价的市场机制。采用集成层次分析法和熵值法确定电能质量各项指标的综合权重值;同时,将空间距离度量的思想应用于电能质量综合评估,将电能质量指标问题转化为空间上的模式距离问题,采用动态时间弯曲算法进行序列模式识别,计算经加权化的标准电能质量指标序列、待评估电能质量指标序列与理想电能质量指标序列的匹配系数,进而确定电能质量等级,实现电能质量的综合评估与分级评估。实例计算结果表明,所提出的综合评估方法具有一定的有效性和可行性。
The quantized result from synthetic evaluation of power quality is one of the foundations to assess power quality and is favorable to implement the market mechanism of pricing electric energy according to power quality.Integrating analytic hierarchy process(AHP) with entropy weight,the synthetical weights of power quality indices are determined;meanwhile,the thinking of spatial distance measurement is applied to synthetical evaluation of power quality to turn the power quality indices into pattern distance in space.The dynamic time wrapping(DTW) algorithm is adopted for sequence pattern identification to calculate matching coefficients among weighted standard power quality index sequence,power quality index sequence to be evaluated and ideal power quality index sequence,and then the grade of power quality is determined to implement the synthetical evaluation and level assessment of power quality.Calculation results of case study show that the proposed synthetical evaluation method is effective and feasible.