为实现区域电网电能质量的有效评价,提出了一种基于纵横向拉开档次法的动态评价算法,该算法充分利用当前与历史数据,体现了评价对象在一段时期内的总体水平.研究中,首先应用纵横向拉开档次法和序关系分析法确定电能质量指标的综合权重,其中客观权重用于突出评价对象的整体差异,主观权重用于反映专家经验;线性加权各项指标值得出评价对象在各时刻的电能质量评价值;最后利用最小方差法对区域电网各时刻的电能质量评价值加权求和,其中时间度的调整体现了对当前与历史数据的重视程度.通过对某供电局的数据分析,验证了该算法的性能.
In order to effectively evaluate the power quality of regional power grids, a dynamic evaluation algorithm based on the vertical and horizontal scatter degree method, which makes full use of the current and historical data and reflects the overall level of the evaluated objects in a certain period, is proposed. In the investigation, the synthesized weights of power quality indexes are determined via the vertical and horizontal scatter degree method and the sequence-relation analysis, in which the objective weights are used to highlight the overall differences of the evaluated objects and the subjective weights are used to reflect the expert experience. Then, by linearly weighting each index, the evaluation value of power quality in each period is obtained for each evaluated object. Moreover, the least variance method is employed to compute the sum of the evaluated power quality in each period for a regional network; therein the time degree is adjusted to emphasize the current and the historical data. The performance of the proposed algorithm is finally verified by a case study on the power quality of a power supply bureau.