A comparison of the effectiveness of installing reactive power compensators,such as shunt capacitors,static var compensators(SVCs),and static synchronous compensators(STATCOMs),was presented in large-scale power netwo...A comparison of the effectiveness of installing reactive power compensators,such as shunt capacitors,static var compensators(SVCs),and static synchronous compensators(STATCOMs),was presented in large-scale power networks.A suitable bus was first identified using modal analysis method.The single shunt capacitor,single SVC,and single STATCOM were installed separately on the most critical bus.The effects of the installation of different devices on power loss reduction,voltage profile improvement,and voltage stability margin enhancement were examined and compared for 57-and 118-bus transmission systems.The comparative study results show that SVC,and STATCOM are expensive compared to shunt capacitor,yet the effect of installing STATCOM is better than SVC and the effect of installing SVC is better than that of shunt capacitor in achieving power loss reduction,voltage profile improvement and voltage stability margin enhancement.展开更多
Iron oxide is a promising anode material for lithium ion batteries, but it usually exhibits poor electrochemical property because of its poor conductivity and large volume variation during the lithium uptake and relea...Iron oxide is a promising anode material for lithium ion batteries, but it usually exhibits poor electrochemical property because of its poor conductivity and large volume variation during the lithium uptake and release processes. In this work, a double protection strategy for improving electrochemical performance of Fe3O4 nanoparticles through the use of decoration with multi-walled carbon nanotubes and reduced graphene oxides networks has been developed. The resulting MWCNTs-Fe3O4-rGO nanocomposites exhibited excellent cycling performance and rate capability in comparison with MWCNTs-Fe3O4, MWCNTs-Fe3O4 physically mixed with rGO, and Fe3O4-rGO. A reversible capacity of -680 mA·h·g^-1 can be maintained after 100 cycles under a current density of 200 mA.g^-1.展开更多
文摘A comparison of the effectiveness of installing reactive power compensators,such as shunt capacitors,static var compensators(SVCs),and static synchronous compensators(STATCOMs),was presented in large-scale power networks.A suitable bus was first identified using modal analysis method.The single shunt capacitor,single SVC,and single STATCOM were installed separately on the most critical bus.The effects of the installation of different devices on power loss reduction,voltage profile improvement,and voltage stability margin enhancement were examined and compared for 57-and 118-bus transmission systems.The comparative study results show that SVC,and STATCOM are expensive compared to shunt capacitor,yet the effect of installing STATCOM is better than SVC and the effect of installing SVC is better than that of shunt capacitor in achieving power loss reduction,voltage profile improvement and voltage stability margin enhancement.
文摘Iron oxide is a promising anode material for lithium ion batteries, but it usually exhibits poor electrochemical property because of its poor conductivity and large volume variation during the lithium uptake and release processes. In this work, a double protection strategy for improving electrochemical performance of Fe3O4 nanoparticles through the use of decoration with multi-walled carbon nanotubes and reduced graphene oxides networks has been developed. The resulting MWCNTs-Fe3O4-rGO nanocomposites exhibited excellent cycling performance and rate capability in comparison with MWCNTs-Fe3O4, MWCNTs-Fe3O4 physically mixed with rGO, and Fe3O4-rGO. A reversible capacity of -680 mA·h·g^-1 can be maintained after 100 cycles under a current density of 200 mA.g^-1.
