Based on the changing law of municipal water demand,a trigonometric function model for short-term water demand forecast is established using the time-series analysis approach.The method for forecasting water demand du...Based on the changing law of municipal water demand,a trigonometric function model for short-term water demand forecast is established using the time-series analysis approach.The method for forecasting water demand during holidays and under unexpected events is also presented.Meanwhile,a computer software is developed.Through actual application,this method performs well and has high accuracy,so it can be applied to the daily operation of a water distribution system and lay a foundation for on-line optimal operation.展开更多
Short-term forecasting is a difficult problem because of the influence of non-linear factors and irregular events.A novel short-term forecasting method named TIK was proposed,in which ARMA forecasting model was used t...Short-term forecasting is a difficult problem because of the influence of non-linear factors and irregular events.A novel short-term forecasting method named TIK was proposed,in which ARMA forecasting model was used to consider the load time series trend forecasting,intelligence forecasting DESVR model was applied to estimate the non-linear influence,and knowledge mining methods were applied to correct the errors caused by irregular events.In order to prove the effectiveness of the proposed model,an application of the daily maximum load forecasting was evaluated.The experimental results show that the DESVR model improves the mean absolute percentage error(MAPE) from 2.82% to 2.55%,and the knowledge rules can improve the MAPE from 2.55% to 2.30%.Compared with the single ARMA forecasting method and ARMA combined SVR forecasting method,it can be proved that TIK method gains the best performance in short-term load forecasting.展开更多
The mining of the rules from the electrical load time series data which are collected from the EMS (Energy Management System) is discussed. The data from the EMS are too huge and sophisticated to be understood and use...The mining of the rules from the electrical load time series data which are collected from the EMS (Energy Management System) is discussed. The data from the EMS are too huge and sophisticated to be understood and used by the power system engineer, while useful information is hidden in the electrical load data. The authors discuss the use of fuzzy linguistic summary as data mining method to induce the rules from the electrical load time series. The data preprocessing techniques are also discussed in the paper.展开更多
随着分布式电源(distributed generation,DG)渗透率在主动配电网(active distribution network,ADN)中不断增加,配电网运行规划难度也不断提高。尤其是故障时配电网形成孤岛运行后,DG出力与负荷需求分配不均,供电效率下降的情况居多。...随着分布式电源(distributed generation,DG)渗透率在主动配电网(active distribution network,ADN)中不断增加,配电网运行规划难度也不断提高。尤其是故障时配电网形成孤岛运行后,DG出力与负荷需求分配不均,供电效率下降的情况居多。该文针对以上问题对主动配电网故障后孤岛运行展开研究,考虑DG的间歇性出力对其建立概率模型,同时对需求侧负荷进行时序性建模,提出一种基于多时段DG-负荷有功功率平衡的孤岛划分方法。在DG出力不足的情况下,根据负荷优先级和可控度采用遗传算法进行最优切负荷,精准切除优先级低的负荷,保证多负荷、重要负荷供电。最后通过PG&E 69配电网算例验证所提方法的有效性和可行性,结果显示,该方法能在一定程度上有效增加孤岛供电范围。展开更多
基金Natural Science Foundation of China!(No.598780 30 )
文摘Based on the changing law of municipal water demand,a trigonometric function model for short-term water demand forecast is established using the time-series analysis approach.The method for forecasting water demand during holidays and under unexpected events is also presented.Meanwhile,a computer software is developed.Through actual application,this method performs well and has high accuracy,so it can be applied to the daily operation of a water distribution system and lay a foundation for on-line optimal operation.
基金Projects(70671039,71071052) supported by the National Natural Science Foundation of ChinaProjects(10QX44,09QX68) supported by the Fundamental Research Funds for the Central Universities in China
文摘Short-term forecasting is a difficult problem because of the influence of non-linear factors and irregular events.A novel short-term forecasting method named TIK was proposed,in which ARMA forecasting model was used to consider the load time series trend forecasting,intelligence forecasting DESVR model was applied to estimate the non-linear influence,and knowledge mining methods were applied to correct the errors caused by irregular events.In order to prove the effectiveness of the proposed model,an application of the daily maximum load forecasting was evaluated.The experimental results show that the DESVR model improves the mean absolute percentage error(MAPE) from 2.82% to 2.55%,and the knowledge rules can improve the MAPE from 2.55% to 2.30%.Compared with the single ARMA forecasting method and ARMA combined SVR forecasting method,it can be proved that TIK method gains the best performance in short-term load forecasting.
文摘The mining of the rules from the electrical load time series data which are collected from the EMS (Energy Management System) is discussed. The data from the EMS are too huge and sophisticated to be understood and used by the power system engineer, while useful information is hidden in the electrical load data. The authors discuss the use of fuzzy linguistic summary as data mining method to induce the rules from the electrical load time series. The data preprocessing techniques are also discussed in the paper.
文摘随着分布式电源(distributed generation,DG)渗透率在主动配电网(active distribution network,ADN)中不断增加,配电网运行规划难度也不断提高。尤其是故障时配电网形成孤岛运行后,DG出力与负荷需求分配不均,供电效率下降的情况居多。该文针对以上问题对主动配电网故障后孤岛运行展开研究,考虑DG的间歇性出力对其建立概率模型,同时对需求侧负荷进行时序性建模,提出一种基于多时段DG-负荷有功功率平衡的孤岛划分方法。在DG出力不足的情况下,根据负荷优先级和可控度采用遗传算法进行最优切负荷,精准切除优先级低的负荷,保证多负荷、重要负荷供电。最后通过PG&E 69配电网算例验证所提方法的有效性和可行性,结果显示,该方法能在一定程度上有效增加孤岛供电范围。
