The existing power management schemes for interlinked AC-DC microgrids have several operational drawbacks.Some of the existing control schemes are designed with the main objective of sharing power among the interlinke...The existing power management schemes for interlinked AC-DC microgrids have several operational drawbacks.Some of the existing control schemes are designed with the main objective of sharing power among the interlinked microgrids based on their loading conditions,while other schemes regulate the voltage of the interlinked microgrids without considering the specific loading conditions.However,the existing schemes cannot achieve both objectives efficiently.To address these issues,an autonomous power management scheme is proposed,which explicitly considers the specific loading condition of the DC microgrid before importing power from the interlinked AC microgrid.This strategy enables voltage regulation in the DC microgrid,and also reduces the number of converters in operation.The proposed scheme is fully autonomous while it retains the plug-nplay features for generators and tie-converters.The performance of the proposed control scheme has been validated under different operating scenarios.The results demonstrate the effectiveness of the proposed scheme in managing the power deficit in the DC microgrid efficiently and autonomously while maintaining the better voltage regulation in the DC microgrid.展开更多
In May 1983,the governor of Hebei province,Zhang Shuguang,and the governor of the US state of Iowa,Terry Branstad,signed an agreemen t to establish friendly relations between the two areas in the state capital,Des Moi...In May 1983,the governor of Hebei province,Zhang Shuguang,and the governor of the US state of Iowa,Terry Branstad,signed an agreemen t to establish friendly relations between the two areas in the state capital,Des Moines.Two years later,in May 1985,Xi Jinping,secretary of the Zhengding County Committee of the Communist Party of China in Hebei.展开更多
The equilibrium between dc bus voltage and ac bus frequency(Udc-f equilibrium)is the algorithm core of unified control strategies for ac-dc interlinking converters(ILCs),because the equilibrium implements certain mech...The equilibrium between dc bus voltage and ac bus frequency(Udc-f equilibrium)is the algorithm core of unified control strategies for ac-dc interlinking converters(ILCs),because the equilibrium implements certain mechanism.However,what the mechanism is has not been explicitly explored,which hinders further studies on unified control.This paper reveals that the state-space model of a Udc-f equilibrium controlled ILC is highly similar to that of a shaft-to-shaft machines system.Hence a detailed mechanism is dis-covered and named“virtual shaft-to-shaft machine(VSSM)”mechanism.A significant feature of VSSM mechanism is self-synchro-nization without current sampling or ac voltage sampling.展开更多
As a layered two-dimensional material,MoSe_(2)exhibits interlayer-tunable properties and exceptional theoretical capacities,making it a promising candidate for sodium/potassium ion storage systems.Nevertheless,its ina...As a layered two-dimensional material,MoSe_(2)exhibits interlayer-tunable properties and exceptional theoretical capacities,making it a promising candidate for sodium/potassium ion storage systems.Nevertheless,its inadequate conductivity and irreversible reactions during charge and discharge seriously affect its electrochemical performance.Herein,a hierarchical interlayer-expanded MoSe_(2)/C(IE-MoSe_(2)/C)hybrid architecture with interlinked hollow nanospheres is engineered via a two-stage fabrication process combining hydrothermal self-assembly and controlled pyrolysis.The interlayer spacing increases to 1.02 nm,which accelerates the transport of sodium and potassium ions.Additionally,the strong interface between carbon and MoSe_(2)improves the conductivity,thereby enhancing the electrochemical kinetics of sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).On the other hand,the unique hierarchical IE-MoSe_(2)/C structure with hollow nanospheres can effectively mitigate variations in volume during cycling.Thus,IE-MoSe_(2)/C exhibits outstanding electrochemical characteristics as an anode material for SIBs and PIBs.Specifically,IE-MoSe_(2)/C exhibits better rate capability(98 mAh g^(−1)at 20 A g^(−1)in SIBs)and cycling performance(269/174 mAh g^(−1)at 2.0/5.0 A g^(−1)over 1100 cycles in SIBs and 133/96 mAh g^(−1)at 1.0/2.0 A g^(−1)over 1000 cycles for PIBs).Additionally,at 0.5C,the full cell of IE-MoSe_(2)/C||Na_(3)V_(2)(PO_(4))_(3)can display a consistent capacity of 93 mAh g^(−1),demonstrating the potential for future practical applications.展开更多
An 8-hydroxyquinolinate-based metal–organic framework[Zn(L)]·2MeOH·H_(2)O(1)was synthesized for the first time by treating a novel 8-hydroxyquinolinate ligand H_(2)L involving two carboxylate groups with zi...An 8-hydroxyquinolinate-based metal–organic framework[Zn(L)]·2MeOH·H_(2)O(1)was synthesized for the first time by treating a novel 8-hydroxyquinolinate ligand H_(2)L involving two carboxylate groups with zinc salt.Based on single-crystal X-ray analysis,the Zn-MOF exhibits a porous framework assembled from interlinked nanotubes that are constructed from three 4_(3)helices.展开更多
文摘The existing power management schemes for interlinked AC-DC microgrids have several operational drawbacks.Some of the existing control schemes are designed with the main objective of sharing power among the interlinked microgrids based on their loading conditions,while other schemes regulate the voltage of the interlinked microgrids without considering the specific loading conditions.However,the existing schemes cannot achieve both objectives efficiently.To address these issues,an autonomous power management scheme is proposed,which explicitly considers the specific loading condition of the DC microgrid before importing power from the interlinked AC microgrid.This strategy enables voltage regulation in the DC microgrid,and also reduces the number of converters in operation.The proposed scheme is fully autonomous while it retains the plug-nplay features for generators and tie-converters.The performance of the proposed control scheme has been validated under different operating scenarios.The results demonstrate the effectiveness of the proposed scheme in managing the power deficit in the DC microgrid efficiently and autonomously while maintaining the better voltage regulation in the DC microgrid.
文摘In May 1983,the governor of Hebei province,Zhang Shuguang,and the governor of the US state of Iowa,Terry Branstad,signed an agreemen t to establish friendly relations between the two areas in the state capital,Des Moines.Two years later,in May 1985,Xi Jinping,secretary of the Zhengding County Committee of the Communist Party of China in Hebei.
基金supported in part by the National Natural Science Foundation of China under Grants 51877117 and 52007096the International Joint Mission On Climate Change and Carbon Neutralitythe Major Science and Technology Innovation Project of Jiangsu Province of China under Grant BE2022038.
文摘The equilibrium between dc bus voltage and ac bus frequency(Udc-f equilibrium)is the algorithm core of unified control strategies for ac-dc interlinking converters(ILCs),because the equilibrium implements certain mechanism.However,what the mechanism is has not been explicitly explored,which hinders further studies on unified control.This paper reveals that the state-space model of a Udc-f equilibrium controlled ILC is highly similar to that of a shaft-to-shaft machines system.Hence a detailed mechanism is dis-covered and named“virtual shaft-to-shaft machine(VSSM)”mechanism.A significant feature of VSSM mechanism is self-synchro-nization without current sampling or ac voltage sampling.
基金support from the National Natural Science Foundation of China(Grant No.52271208 and 51972092)the Fundamental Research Funds for the Central Universities(Grant No.JZ2024HGTG0305).
文摘As a layered two-dimensional material,MoSe_(2)exhibits interlayer-tunable properties and exceptional theoretical capacities,making it a promising candidate for sodium/potassium ion storage systems.Nevertheless,its inadequate conductivity and irreversible reactions during charge and discharge seriously affect its electrochemical performance.Herein,a hierarchical interlayer-expanded MoSe_(2)/C(IE-MoSe_(2)/C)hybrid architecture with interlinked hollow nanospheres is engineered via a two-stage fabrication process combining hydrothermal self-assembly and controlled pyrolysis.The interlayer spacing increases to 1.02 nm,which accelerates the transport of sodium and potassium ions.Additionally,the strong interface between carbon and MoSe_(2)improves the conductivity,thereby enhancing the electrochemical kinetics of sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).On the other hand,the unique hierarchical IE-MoSe_(2)/C structure with hollow nanospheres can effectively mitigate variations in volume during cycling.Thus,IE-MoSe_(2)/C exhibits outstanding electrochemical characteristics as an anode material for SIBs and PIBs.Specifically,IE-MoSe_(2)/C exhibits better rate capability(98 mAh g^(−1)at 20 A g^(−1)in SIBs)and cycling performance(269/174 mAh g^(−1)at 2.0/5.0 A g^(−1)over 1100 cycles in SIBs and 133/96 mAh g^(−1)at 1.0/2.0 A g^(−1)over 1000 cycles for PIBs).Additionally,at 0.5C,the full cell of IE-MoSe_(2)/C||Na_(3)V_(2)(PO_(4))_(3)can display a consistent capacity of 93 mAh g^(−1),demonstrating the potential for future practical applications.
基金supported by the National Natural Science Foundation of China(Grants 21671002 and 21603001)Anhui Province Natural Science Funds for Distinguished Young Scholar(Grants 1808085J25)the Provincial Natural Science Research Program of Higher Education Institutions of Anhui Province(KJ2019A0071).
文摘An 8-hydroxyquinolinate-based metal–organic framework[Zn(L)]·2MeOH·H_(2)O(1)was synthesized for the first time by treating a novel 8-hydroxyquinolinate ligand H_(2)L involving two carboxylate groups with zinc salt.Based on single-crystal X-ray analysis,the Zn-MOF exhibits a porous framework assembled from interlinked nanotubes that are constructed from three 4_(3)helices.
