In this paper,we first discuss the boundedness of certain integral operator T_(t) on the normal weight general function space F(p,μ,s)in the unit ball Bnof C^(n).As an application of this operator,we prove that the G...In this paper,we first discuss the boundedness of certain integral operator T_(t) on the normal weight general function space F(p,μ,s)in the unit ball Bnof C^(n).As an application of this operator,we prove that the Gleason’s problem is solvable on F(p,μ,s).展开更多
基于模块化多电平换流器的高压柔性直流输电系统(modular multilevel converter-based high voltage direct current,MMC-HVDC)常采用双极接线方式以提高系统功率输送能力和可靠性。然而目前对于风电场经柔直外送系统的稳定性研究集中...基于模块化多电平换流器的高压柔性直流输电系统(modular multilevel converter-based high voltage direct current,MMC-HVDC)常采用双极接线方式以提高系统功率输送能力和可靠性。然而目前对于风电场经柔直外送系统的稳定性研究集中于单极接线方式,孤岛直驱风电场与采用不同双极协调控制的双极MMC-HVDC互联系统小信号稳定性问题还有待进一步探究。该文首先考虑频率耦合特性、参考系初相位和直流侧耦合特性的影响,分别建立了采用双U/f下垂控制和定U/f-P/Q控制的双极MMC-HVDC系统交流侧等效SISO阻抗模型,并详细分析了金属回线阻抗和双极间功率均分度对交流阻抗特性的影响。接着对比研究了两种协调控制中共有控制环路和特有控制环路对交流侧负电阻特性及互联系统稳定性的影响规律。最后,孤岛直驱风电场经两种双极协调控制下双极MMC-HVDC外送系统Matlab/Simulink时域仿真结果和硬件在环半实物实时仿真实验结果验证了所提出的小信号阻抗模型的精确性和稳定性分析结论的有效性。展开更多
In this article the electron is conceived as an extended particle, consisting of a negatively charged core (-q<sub>0</sub>) which is surrounded by a cloud of electric dipoles (-q, +q). The article presents...In this article the electron is conceived as an extended particle, consisting of a negatively charged core (-q<sub>0</sub>) which is surrounded by a cloud of electric dipoles (-q, +q). The article presents the illustrations that show how and why the electron spins and radiates in an external electric field. In the appendices, Bremsstrahlung & Cerenkov radiations, and the processes of Emission & Absorption of photons will be discussed.展开更多
基金Supported by the National Natural Science Foundation of China(11942109)the Natural Science Foundation of Hunan Province in China(2022JJ30369)。
文摘In this paper,we first discuss the boundedness of certain integral operator T_(t) on the normal weight general function space F(p,μ,s)in the unit ball Bnof C^(n).As an application of this operator,we prove that the Gleason’s problem is solvable on F(p,μ,s).
文摘基于模块化多电平换流器的高压柔性直流输电系统(modular multilevel converter-based high voltage direct current,MMC-HVDC)常采用双极接线方式以提高系统功率输送能力和可靠性。然而目前对于风电场经柔直外送系统的稳定性研究集中于单极接线方式,孤岛直驱风电场与采用不同双极协调控制的双极MMC-HVDC互联系统小信号稳定性问题还有待进一步探究。该文首先考虑频率耦合特性、参考系初相位和直流侧耦合特性的影响,分别建立了采用双U/f下垂控制和定U/f-P/Q控制的双极MMC-HVDC系统交流侧等效SISO阻抗模型,并详细分析了金属回线阻抗和双极间功率均分度对交流阻抗特性的影响。接着对比研究了两种协调控制中共有控制环路和特有控制环路对交流侧负电阻特性及互联系统稳定性的影响规律。最后,孤岛直驱风电场经两种双极协调控制下双极MMC-HVDC外送系统Matlab/Simulink时域仿真结果和硬件在环半实物实时仿真实验结果验证了所提出的小信号阻抗模型的精确性和稳定性分析结论的有效性。
文摘In this article the electron is conceived as an extended particle, consisting of a negatively charged core (-q<sub>0</sub>) which is surrounded by a cloud of electric dipoles (-q, +q). The article presents the illustrations that show how and why the electron spins and radiates in an external electric field. In the appendices, Bremsstrahlung & Cerenkov radiations, and the processes of Emission & Absorption of photons will be discussed.
