As the voltage has local characteristics in a power system, system voltage control has depended on human experts in distribution substation local reactive power control station so far in Korea. Since coordinative auto...As the voltage has local characteristics in a power system, system voltage control has depended on human experts in distribution substation local reactive power control station so far in Korea. Since coordinative automatic control has been possible due to the recent advances in computers and communication networks, the hierarchical voltage control system, consisting of primary, secondary, and tertiary control, has been applied in several European countries. Recently the Korea power system has been operated more closely to stability limits because of rapid growth in load-demand as seen in Europe. For this reasons, Korea electric power corporation recognized the need of the voltage control system and developed the voltage control system. This paper presents an intelligent voltage control system for domestic power system using numerical algorithm based on the sensitivity matrix and the expert system. Dynamic characteristics of the developed system are investigated using EMTDC （electromagnetic transient DC analysis program） and RTDS （real time digital simulator）. Several case studies showed the promising performance.展开更多
This paper proposes a new and distribution-free test called ＂Group Contingency＂ test （GC, for short） for testing two or several independent samples. Compared with traditional nonparametric tests, GC test tends to ...This paper proposes a new and distribution-free test called ＂Group Contingency＂ test （GC, for short） for testing two or several independent samples. Compared with traditional nonparametric tests, GC test tends to explore more information based on samples, and it＇s location-, scale-, and shapesensitive. The authors conduct some simulation studies comparing GC test with Wilcoxon rank sum test （W）, Kolmogorov-Smirnov test （KS） and Wald-Wolfowitz runs test （WW） for two sample case, and with Kruskal-Wallis （KW） for testing several samples. Simulation results reveal that GC test usually outperforms other methods.展开更多
文摘As the voltage has local characteristics in a power system, system voltage control has depended on human experts in distribution substation local reactive power control station so far in Korea. Since coordinative automatic control has been possible due to the recent advances in computers and communication networks, the hierarchical voltage control system, consisting of primary, secondary, and tertiary control, has been applied in several European countries. Recently the Korea power system has been operated more closely to stability limits because of rapid growth in load-demand as seen in Europe. For this reasons, Korea electric power corporation recognized the need of the voltage control system and developed the voltage control system. This paper presents an intelligent voltage control system for domestic power system using numerical algorithm based on the sensitivity matrix and the expert system. Dynamic characteristics of the developed system are investigated using EMTDC （electromagnetic transient DC analysis program） and RTDS （real time digital simulator）. Several case studies showed the promising performance.
基金This research is supported-by the National Natural Science Foundation of China under Grant No. 10731010 and Ph.D. Program Foundation of Ministry of Education of China under Grant No. 20090001110005.
文摘This paper proposes a new and distribution-free test called ＂Group Contingency＂ test （GC, for short） for testing two or several independent samples. Compared with traditional nonparametric tests, GC test tends to explore more information based on samples, and it＇s location-, scale-, and shapesensitive. The authors conduct some simulation studies comparing GC test with Wilcoxon rank sum test （W）, Kolmogorov-Smirnov test （KS） and Wald-Wolfowitz runs test （WW） for two sample case, and with Kruskal-Wallis （KW） for testing several samples. Simulation results reveal that GC test usually outperforms other methods.
