According to the characteristics of the comprehensive evaluation of power quality, the combined weighing method is proposed which decides the subjective weight by clustering analytic hierarchy method and objective weight by entropy weight method. The kernel vector space model is established, the kernel function is used to map the input data to the high-dimensional feature space. In the high-dimensional space, the indexes directed line segment of data sample and ideal directed line segment of standard sample are defined. By calculating the weighted cosine value between directed line segment in each data sample and ideal directed line segment in standard sample, the approach degree is obtained. Transforming the problem of comprehensive evaluation of power quality into the problem of pattern recognition in vector space, the power quality level is obtained. The effectiveness and superiority of the model are verified by results of actual example, and the synthetic evaluation result of power quality is more objective and rational.%针对电能质量综合评估的特点,提出了利用聚类层次分析法确定主观权重和熵权法确定客观权重的组合赋权法.建立核向量空间模型,利用核函数将输入样本映射到高维特征空间,在高维特征空间定义各样本的指标有向线段和电能质量等级标准的理想指标有向线段.采用两线段之间的夹角加权余弦值衡量样本与标准模式的贴近度,将电能质量综合评估问题转化为向量空间的模式识别问题,实现电能质量的综合评估.实际算例表明该方法能够得到客观、合理的综合评估结果,验证了该模型的有效性和优越性.
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