与系统负荷不同,母线负荷水平较低,波动性强,规律性弱,可预测性差,引入虚拟母线技术有利于提高母线负荷预测的工作水平与预测精度。在电网中存在一些紧密联系的连通的局部网络,其内部各母线对关键断面具有相同或相近的发电机输出功率转...与系统负荷不同,母线负荷水平较低,波动性强,规律性弱,可预测性差,引入虚拟母线技术有利于提高母线负荷预测的工作水平与预测精度。在电网中存在一些紧密联系的连通的局部网络,其内部各母线对关键断面具有相同或相近的发电机输出功率转移分布因子(generation shift distribution factor,GSDF),同时其内部母线的负荷曲线具有一定的相似性,这些母线所组成的连通局部母线组为虚拟母线。根据虚拟母线概念,提出一种新颖的聚类预测方法:虚拟母线负荷预测方法;对虚拟母线负荷预测与独立预测的精度进行了比较,分析了预测误差的形成机理,提炼出预测误差的数学表征;针对虚拟母线聚类判据对于提高预测精度的有效性进行了分析;采用河北南网的实际数据验证了虚拟母线负荷预测方法的有效性。展开更多
China, in the transformational period of her societal structure, has become more visibly stratified, with the wealthy and the poor being further polarized and social conflicts increasingly intensified. It is theoretic...China, in the transformational period of her societal structure, has become more visibly stratified, with the wealthy and the poor being further polarized and social conflicts increasingly intensified. It is theoretically and practically vital to study how to sustain social stability, promote social harmony and ensure people’s equal share of the achievements of economic reform and social development. Upon the review of the theories and methods in the area of social stratification used both at home and abroad, and the analysis of the social stratification in China from past to present, the author proposes that an upgraded transformation from a stratified society to a harmonious one will be possible only via building a healthy social mobility mechanism and creating a substantial middle class. Furthermore, eliminating inequality, preventing disturbances, valuing education and tearing down barriers to social mobility should be put into action.展开更多
文摘与系统负荷不同,母线负荷水平较低,波动性强,规律性弱,可预测性差,引入虚拟母线技术有利于提高母线负荷预测的工作水平与预测精度。在电网中存在一些紧密联系的连通的局部网络,其内部各母线对关键断面具有相同或相近的发电机输出功率转移分布因子(generation shift distribution factor,GSDF),同时其内部母线的负荷曲线具有一定的相似性,这些母线所组成的连通局部母线组为虚拟母线。根据虚拟母线概念,提出一种新颖的聚类预测方法:虚拟母线负荷预测方法;对虚拟母线负荷预测与独立预测的精度进行了比较,分析了预测误差的形成机理,提炼出预测误差的数学表征;针对虚拟母线聚类判据对于提高预测精度的有效性进行了分析;采用河北南网的实际数据验证了虚拟母线负荷预测方法的有效性。
文摘China, in the transformational period of her societal structure, has become more visibly stratified, with the wealthy and the poor being further polarized and social conflicts increasingly intensified. It is theoretically and practically vital to study how to sustain social stability, promote social harmony and ensure people’s equal share of the achievements of economic reform and social development. Upon the review of the theories and methods in the area of social stratification used both at home and abroad, and the analysis of the social stratification in China from past to present, the author proposes that an upgraded transformation from a stratified society to a harmonious one will be possible only via building a healthy social mobility mechanism and creating a substantial middle class. Furthermore, eliminating inequality, preventing disturbances, valuing education and tearing down barriers to social mobility should be put into action.
