为满足储能系统提供惯量和一次调频支撑功能需要对多类型储能介质集中配置和优化调控的需求,针对基于模块化多电平换流器(modularmultilevelconverter,MMC)的新型混合储能系统(hybrid energy storage system,HESS)MMC-HESS,提出了混合...为满足储能系统提供惯量和一次调频支撑功能需要对多类型储能介质集中配置和优化调控的需求,针对基于模块化多电平换流器(modularmultilevelconverter,MMC)的新型混合储能系统(hybrid energy storage system,HESS)MMC-HESS,提出了混合同步控制(hybrid synchronous control,HSC)整体策略。MMCHESS采用模块化设计,将超级电容和蓄电池分别安置在高压直流母线侧和子模块内,具备高功率密度和高能量密度的优势。阐述了混合储能系统的拓扑结构和工作原理并采用混合同步控制策略提供系统惯量和一次调频功能及故障限流时的同步能力和孤岛并网切换功能,采用滤波器实现储能功率分配,采用荷电状态(state of charge,SOC)均衡控制实现蓄电池能量均衡。最后,基于硬件在环实验平台,验证了所提拓扑结构与控制策略的可行性和有效性。实验结果表明:所提混合储能系统及其控制策略具备惯量与频率支撑能力,在故障限流、正常并网、孤岛运行之间可灵活切换,能够有效发挥混合储能的综合优势,在中压配电网中具有良好的应用前景。展开更多
The phase states of the catalytic system of FeCl3-Al（i-Bu）3-pyridine are studied in the paper by means of the Tyndall effect, electron microscopy and super-filtration. It is found that the catalyst dispersing in the...The phase states of the catalytic system of FeCl3-Al（i-Bu）3-pyridine are studied in the paper by means of the Tyndall effect, electron microscopy and super-filtration. It is found that the catalyst dispersing in the butadienehydrogasoline solution exists in small particles and the size of particle is 30 nm or so in diameter. The catalyst belongs to a multi-phase catalytic system. The active center of catalyst lies on the surface of nanometer particles, which are amorphous. The ratios of different components of catalyst affect the formation of the particles. With the optimum ratio, nanometer particles, which disperse more uniformly and are of highly catalytic activity, can be obtained.展开更多
An original idea is reviewed. When a molecule is pumped into a super-excited state, one of its decay channels is neutral dissociation. One or more of the neutral fragments will fluoresce. Hence, if a lower state of su...An original idea is reviewed. When a molecule is pumped into a super-excited state, one of its decay channels is neutral dissociation. One or more of the neutral fragments will fluoresce. Hence, if a lower state of such fluorescing fragments was populated through other channels but with a lower probability, population inversion of the fluorescing fragments would be naturally realized. This idea seems to be validated, so far, by comparing published work on three hydrocarbon molecules, CH4, C2H2, C2H4, and water vapor, H2 O. After super-excitation in a femtosecond laser filament in air mixed with these molecules, the fluorescence from the CH or OH fragments exhibits population inversion, i.e., amplified spontaneous emission was observed in the backscattering direction of the filament.展开更多
文摘为满足储能系统提供惯量和一次调频支撑功能需要对多类型储能介质集中配置和优化调控的需求,针对基于模块化多电平换流器(modularmultilevelconverter,MMC)的新型混合储能系统(hybrid energy storage system,HESS)MMC-HESS,提出了混合同步控制(hybrid synchronous control,HSC)整体策略。MMCHESS采用模块化设计,将超级电容和蓄电池分别安置在高压直流母线侧和子模块内,具备高功率密度和高能量密度的优势。阐述了混合储能系统的拓扑结构和工作原理并采用混合同步控制策略提供系统惯量和一次调频功能及故障限流时的同步能力和孤岛并网切换功能,采用滤波器实现储能功率分配,采用荷电状态(state of charge,SOC)均衡控制实现蓄电池能量均衡。最后,基于硬件在环实验平台,验证了所提拓扑结构与控制策略的可行性和有效性。实验结果表明:所提混合储能系统及其控制策略具备惯量与频率支撑能力,在故障限流、正常并网、孤岛运行之间可灵活切换,能够有效发挥混合储能的综合优势,在中压配电网中具有良好的应用前景。
文摘The phase states of the catalytic system of FeCl3-Al（i-Bu）3-pyridine are studied in the paper by means of the Tyndall effect, electron microscopy and super-filtration. It is found that the catalyst dispersing in the butadienehydrogasoline solution exists in small particles and the size of particle is 30 nm or so in diameter. The catalyst belongs to a multi-phase catalytic system. The active center of catalyst lies on the surface of nanometer particles, which are amorphous. The ratios of different components of catalyst affect the formation of the particles. With the optimum ratio, nanometer particles, which disperse more uniformly and are of highly catalytic activity, can be obtained.
基金Project supported by the Canada Research Chairs,the Natural Science and Engineering Research Council of Canada(NSERC),the FRQNT,the Canada Foundation for Innovation(CFI),the National Basic Research Program of China(Grant No.2014CB921300)the National Natural Science Foundation of China(Grant No.61235003)+1 种基金the Research Fund for the Doctoral Program of Higher Education of Chinathe Scientific Research Foundation for Returned Scholars,Ministry of Education of China
文摘An original idea is reviewed. When a molecule is pumped into a super-excited state, one of its decay channels is neutral dissociation. One or more of the neutral fragments will fluoresce. Hence, if a lower state of such fluorescing fragments was populated through other channels but with a lower probability, population inversion of the fluorescing fragments would be naturally realized. This idea seems to be validated, so far, by comparing published work on three hydrocarbon molecules, CH4, C2H2, C2H4, and water vapor, H2 O. After super-excitation in a femtosecond laser filament in air mixed with these molecules, the fluorescence from the CH or OH fragments exhibits population inversion, i.e., amplified spontaneous emission was observed in the backscattering direction of the filament.
