The historical information of loadings on substation helps in evaluation of size of photovoltaic(PV)generation and energy storages for peak shaving and distribution system upgrade deferral. A method, based on consumpt...The historical information of loadings on substation helps in evaluation of size of photovoltaic(PV)generation and energy storages for peak shaving and distribution system upgrade deferral. A method, based on consumption data, is proposed to separate the unusual consumption and to form the clusters of similar regular consumption. The method does optimal partition of the load pattern data into core points and border points, high and less dense regions, respectively. The local outlier factor, which does not require fixed probability distribution of data and statistical measures, ranks the unusual consumptions on only the border points, which are a few percent of the complete data. The suggested method finds the optimal or close to optimal number of clusters of similar shape of load patterns to detect regular peak and valley load demands on different days. Furthermore,identification and characterization of features pertaining to unusual consumptions in load pattern data have been done on border points only. The effectiveness of the proposed method and characterization is tested on two practical distribution systems.展开更多
Non-pressurised air is extensively used as basic insulation medium in high-voltage equipment.Unfortunately,an inherent property of air-insulated design is that the system tends to become physically large.On the other ...Non-pressurised air is extensively used as basic insulation medium in high-voltage equipment.Unfortunately,an inherent property of air-insulated design is that the system tends to become physically large.On the other hand,the application of dielectric barriers can increase the breakdown voltage and therefore decrease the size of the equipment.In this study,the impact of dielectric barriers on breakdown voltage enhancement is investigated under both direct current(dc)and alternating current(ac)applied voltages.For this purpose,three kinds of dielectric barriers in two different high-voltage electrode structures are investigated.In the first structure,several experiments are carried out with four different electrode arrangements,keeping the inter-electrode gap constant while varying the position of the dielectric barrier between the electrodes.In the second structure,the inter-electrode gap is varied while the high-voltage electrode is covered with dielectric materials.The influences of different parameters such as inter-electrode spacing,electric field non-uniformity factor,and dielectric materials on the breakdown voltage are investigated for applied 50 Hz ac and dc voltages.In addition,a simulation model to approximately calculate the breakdown voltage is proposed and validated with the experimental results.展开更多
基金supported by the Department of Science and Technology(DST),New Delhi,India(No.DST/EE/2014127)
文摘The historical information of loadings on substation helps in evaluation of size of photovoltaic(PV)generation and energy storages for peak shaving and distribution system upgrade deferral. A method, based on consumption data, is proposed to separate the unusual consumption and to form the clusters of similar regular consumption. The method does optimal partition of the load pattern data into core points and border points, high and less dense regions, respectively. The local outlier factor, which does not require fixed probability distribution of data and statistical measures, ranks the unusual consumptions on only the border points, which are a few percent of the complete data. The suggested method finds the optimal or close to optimal number of clusters of similar shape of load patterns to detect regular peak and valley load demands on different days. Furthermore,identification and characterization of features pertaining to unusual consumptions in load pattern data have been done on border points only. The effectiveness of the proposed method and characterization is tested on two practical distribution systems.
文摘Non-pressurised air is extensively used as basic insulation medium in high-voltage equipment.Unfortunately,an inherent property of air-insulated design is that the system tends to become physically large.On the other hand,the application of dielectric barriers can increase the breakdown voltage and therefore decrease the size of the equipment.In this study,the impact of dielectric barriers on breakdown voltage enhancement is investigated under both direct current(dc)and alternating current(ac)applied voltages.For this purpose,three kinds of dielectric barriers in two different high-voltage electrode structures are investigated.In the first structure,several experiments are carried out with four different electrode arrangements,keeping the inter-electrode gap constant while varying the position of the dielectric barrier between the electrodes.In the second structure,the inter-electrode gap is varied while the high-voltage electrode is covered with dielectric materials.The influences of different parameters such as inter-electrode spacing,electric field non-uniformity factor,and dielectric materials on the breakdown voltage are investigated for applied 50 Hz ac and dc voltages.In addition,a simulation model to approximately calculate the breakdown voltage is proposed and validated with the experimental results.