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
Hierarchical time series arise in manufacturing and service industries when the products or services have the hierarchical structure,and top-down and bottomup methods are commonly used to forecast the hierarchical tim...Hierarchical time series arise in manufacturing and service industries when the products or services have the hierarchical structure,and top-down and bottomup methods are commonly used to forecast the hierarchical time series.One of the critical factors that affect the performance of the two methods is the correlation between the data series.This study attempts to resolve the problem and shows that the top-down method performs better when data have high positive correlation compared to high negative correlation and combination of forecasting methods may be the best solution when there is no evidence of the correlationship.We conduct the computational experiments using 240 monthly data series from the‘Industrial’category of the M3-Competition and test twelve combination methods for the hierarchical data series.The results show that the regression-based,VAR-COV and the Rank-based methods perform better compared to the other methods.展开更多
现有的运作策略不能实现定制产品的即时交付。在T R IZ创新理论的指导下,通过综合按(传统需求)预测生产实现即时交付和按订单生产实现定制的机理,提出了按个性化需求预测生产的运作策略;为了提高个性化需求预测的准确率,提出了个性化需...现有的运作策略不能实现定制产品的即时交付。在T R IZ创新理论的指导下,通过综合按(传统需求)预测生产实现即时交付和按订单生产实现定制的机理,提出了按个性化需求预测生产的运作策略;为了提高个性化需求预测的准确率,提出了个性化需求预测的七条基本原则,并对传统需求预测和个性化需求预测进行了比较;在此基础上,进一步分析得出了采取按个性化需求预测生产运作策略时实现即时顾客化定制的可能域,实现即时顾客化定制可能域为即时顾客化定制的进一步研究指明了方向;最后对按个性化需求预测生产运作策略进行了案例分析,结果表明该运作策略的可行性。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。
基金This work was supported by Program of Shanghai Subject Chief Scientist[16XD1401700]National Natural Science Foundation of China[71421002].
文摘Hierarchical time series arise in manufacturing and service industries when the products or services have the hierarchical structure,and top-down and bottomup methods are commonly used to forecast the hierarchical time series.One of the critical factors that affect the performance of the two methods is the correlation between the data series.This study attempts to resolve the problem and shows that the top-down method performs better when data have high positive correlation compared to high negative correlation and combination of forecasting methods may be the best solution when there is no evidence of the correlationship.We conduct the computational experiments using 240 monthly data series from the‘Industrial’category of the M3-Competition and test twelve combination methods for the hierarchical data series.The results show that the regression-based,VAR-COV and the Rank-based methods perform better compared to the other methods.
文摘现有的运作策略不能实现定制产品的即时交付。在T R IZ创新理论的指导下,通过综合按(传统需求)预测生产实现即时交付和按订单生产实现定制的机理,提出了按个性化需求预测生产的运作策略;为了提高个性化需求预测的准确率,提出了个性化需求预测的七条基本原则,并对传统需求预测和个性化需求预测进行了比较;在此基础上,进一步分析得出了采取按个性化需求预测生产运作策略时实现即时顾客化定制的可能域,实现即时顾客化定制可能域为即时顾客化定制的进一步研究指明了方向;最后对按个性化需求预测生产运作策略进行了案例分析,结果表明该运作策略的可行性。
