An approach of training working staff of power system operation mode based on state evaluation is proposed. In terms of knowledge features of power system operation mode, we studied a training method based on evaluati...An approach of training working staff of power system operation mode based on state evaluation is proposed. In terms of knowledge features of power system operation mode, we studied a training method based on evaluation of learning state. This training method makes individual learning for different individual condition to give them ability to grasp learning points quickly, evaluate real-time learning effect, update learning style in time and summarize problems after one learning stage, so that learners can master professional knowledge in constant summaries and feedbacks. Obvious effects can be obtained on discontinuous learning time that trainees can master basic theories associated with their working and operations adapted to practical work quickly.展开更多
The nuclear power plant is suitable for base-load operation, while the pumped-storage unit mainly gives play to capacity benefit in the electric power system;hence, the integrated development and hybrid operation mode...The nuclear power plant is suitable for base-load operation, while the pumped-storage unit mainly gives play to capacity benefit in the electric power system;hence, the integrated development and hybrid operation mode of the two can better meet the needs of the electric power system. This article first presents an analysis of the necessity and superiority of such mode, then explains its meaning and analyzes the working routes. Finally, it proposes the business modes as follows: low price pumping water electricity plus nuclear power in the near term;nuclear power shifted to pumped storage power participating in market competition in the middle term;and, in the long term, nuclear power shifted to pumped storage power as primary and serving as an electric power system when needed.展开更多
The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agemen...The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agement of state-owned assets,and the improvement of the operating bene-展开更多
For the low utilization rate of photovoltaic power generation,taking a new energy power system constisting of concentrating solar power(CSP),photovoltaic power(PP)and battery energy storage system as an example,a mult...For the low utilization rate of photovoltaic power generation,taking a new energy power system constisting of concentrating solar power(CSP),photovoltaic power(PP)and battery energy storage system as an example,a multi-objective optimization scheduling strategy considering energy storage participation is proposed.Firstly,the new energy power system model is established,and the PP scenario generation and reduction frame based on the autoregressive moving average model and Kantorovich-distance is proposed.Then,based on the optimization goal of the system operation cost minimization and the PP output power consumption maximization,the multi-objective optimization scheduling model is established.Finally,the simulation results show that introducing energy storage into the system can effectively reduce the system operation cost and improve the utilization efficiency of PP.展开更多
The paper introduces the present status and development objec- tives of the operational support systems of the three telecommuni- cation operators in China and briefly describes the features of the new generation tele...The paper introduces the present status and development objec- tives of the operational support systems of the three telecommuni- cation operators in China and briefly describes the features of the new generation telecommunication operational support system (NGOSS),such as adopting the TMN/TOM structure,supporting the unified and multiple access processing,conducting effective and centralized management of data.展开更多
We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±,...We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±, Jz) from the point of view of squeezing we find that (J±,Jz) can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation (the eigenvectors of J+ or J-) of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU(2) transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU(2) and new squeezing operators.展开更多
We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. Fo...We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.展开更多
As the increasing number of wind energy is integrated into the national power grid,analyses of wind energy are becoming increasingly more crucial.The interaction between the topography and the northeast(NE)monsoon bri...As the increasing number of wind energy is integrated into the national power grid,analyses of wind energy are becoming increasingly more crucial.The interaction between the topography and the northeast(NE)monsoon brings abundant wind resources to the Taiwan Strait in autumn and winter.The offshore area has stronger and more stable wind resources,so deployment of offshore wind power is also actively being carried out.However,development of offshore wind power systems requires stricter evaluation and decision-making.Therefore,this study implements a multi-site measurement verification to establish the relationship between the wind resources of the nearshore wind turbine system and a potential offshore power site in Chanbin.In the absence of a wind turbine at a specific location,potential of offshore wind energy is analyzed through wind resources.The findings showed that although the distance between these two sites is substantial,the nearshore and offshore areas at Chanbin experience similar wind conditions,and nearshore wind turbine can respond well to changes in wind speed and generate power accordingly.Afterwards,on this basis,the offshore power potential was evaluated and compared with the nearshore wind turbine systems.The results suggested the advantages of offshore wind power.A further analysis of the differences between power generation on a monthly basis was carried out to determine the distribution of wind turbine operation modes and illustrate the influence of the NE monsoon.展开更多
This study proposes a novel combined primary and secondary control approach for direct current microgrids,specifi-cally in islanded mode.In primary control,this approach establishes an appropriate load power sharing b...This study proposes a novel combined primary and secondary control approach for direct current microgrids,specifi-cally in islanded mode.In primary control,this approach establishes an appropriate load power sharing between the distributed energy resources based on their rated power.Simultaneously,it considers the load voltage deviation and provides satisfactory voltage regulation in the secondary control loop.The proposed primary control is based on an efficient droop mechanism that only deploys the local variable measurements,so as to overcome the side effects caused by communication delays.In the case of secondary control,two different methods are devised.In the first,low bandwidth communication links are used to establish the minimum required data transfer between the converters.The effect of communication delay is further explored.The second method excludes any communication link and only uses local variables.Accordingly,a self-sufficient control loop is devised without any communication require-ment.The proposed control notions are investigated in MATLAB/Simulink platform to highlight system performance.The results demonstrate that both proposed approaches can effectively compensate for the voltage deviation due to the primary control task.Detailed comparisons of the two methods are also provided.展开更多
The mode-area scaling properties of helical-core optical fibres are numerically studied and the limit of core size for achievable single-mode operation is explored. By appropriate design, helical-core fibres can opera...The mode-area scaling properties of helical-core optical fibres are numerically studied and the limit of core size for achievable single-mode operation is explored. By appropriate design, helical-core fibres can operate in a single mode with possible scaling up to 300μm in core diameter with numerical aperture 0.1.展开更多
为研究兆瓦级高效紧凑型核动力系统的运行特性,使用自主开发的热管堆瞬态分析程序TAPIRS(Transient Analysis code for heat Pipe and AMTEC power conversion space Reactor power System)和超临界二氧化碳布雷顿循环的瞬态分析程序SCT...为研究兆瓦级高效紧凑型核动力系统的运行特性,使用自主开发的热管堆瞬态分析程序TAPIRS(Transient Analysis code for heat Pipe and AMTEC power conversion space Reactor power System)和超临界二氧化碳布雷顿循环的瞬态分析程序SCTRAN/CO_(2)(Super Critical reactors Transient Analysis code/Carbon Dioxide)的耦合程序对其反应性、负荷、冷却水温度和流量等扰动进行了开环动态响应分析,并据此进行了控制系统设计。在此基础上,对线性变负荷、阶梯式变负荷以及甩负荷这三种变负荷运行工况进行了计算分析。结果表明:该核动力系统的转速对扰动的变化较为敏感,需要加以控制;低负荷下旁通会使压缩机流量上升,需对压缩机流量加以控制;系统在控制方案下能以6%FP(Full Power)·min^(−1)的速度实现0%~100%的负荷变动,且可以在任意负荷水平下运行;甩负荷下系统的波动时间变长,但是仍可达到新的稳态进行工作,且各参数处于安全范围内。本研究可为新型核动力系统的概念设计提供参考。展开更多
文摘An approach of training working staff of power system operation mode based on state evaluation is proposed. In terms of knowledge features of power system operation mode, we studied a training method based on evaluation of learning state. This training method makes individual learning for different individual condition to give them ability to grasp learning points quickly, evaluate real-time learning effect, update learning style in time and summarize problems after one learning stage, so that learners can master professional knowledge in constant summaries and feedbacks. Obvious effects can be obtained on discontinuous learning time that trainees can master basic theories associated with their working and operations adapted to practical work quickly.
基金funded by the Project “Resource Characteristics of Main Watersheds and Key Issues in Development and Utilization of Hydroelectricity in South America and Africa”the National Science Foundation of China (U1766201)
文摘The nuclear power plant is suitable for base-load operation, while the pumped-storage unit mainly gives play to capacity benefit in the electric power system;hence, the integrated development and hybrid operation mode of the two can better meet the needs of the electric power system. This article first presents an analysis of the necessity and superiority of such mode, then explains its meaning and analyzes the working routes. Finally, it proposes the business modes as follows: low price pumping water electricity plus nuclear power in the near term;nuclear power shifted to pumped storage power participating in market competition in the middle term;and, in the long term, nuclear power shifted to pumped storage power as primary and serving as an electric power system when needed.
文摘The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agement of state-owned assets,and the improvement of the operating bene-
基金Science and Technology Project of State Grid Corporation of China(No.SGGSKY00FJJS1800140)。
文摘For the low utilization rate of photovoltaic power generation,taking a new energy power system constisting of concentrating solar power(CSP),photovoltaic power(PP)and battery energy storage system as an example,a multi-objective optimization scheduling strategy considering energy storage participation is proposed.Firstly,the new energy power system model is established,and the PP scenario generation and reduction frame based on the autoregressive moving average model and Kantorovich-distance is proposed.Then,based on the optimization goal of the system operation cost minimization and the PP output power consumption maximization,the multi-objective optimization scheduling model is established.Finally,the simulation results show that introducing energy storage into the system can effectively reduce the system operation cost and improve the utilization efficiency of PP.
文摘The paper introduces the present status and development objec- tives of the operational support systems of the three telecommuni- cation operators in China and briefly describes the features of the new generation telecommunication operational support system (NGOSS),such as adopting the TMN/TOM structure,supporting the unified and multiple access processing,conducting effective and centralized management of data.
基金supported by the National Natural Science Foundation of China(Grant Nos.11175113 and 11275123)the Key Project of Natural Science Fund of Anhui Province,China(Grant No.KJ2013A261)
文摘We consider the quantum mechanical SU(2) transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU(2) operators (J±, Jz) from the point of view of squeezing we find that (J±,Jz) can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation (the eigenvectors of J+ or J-) of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU(2) transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU(2) and new squeezing operators.
基金Supported by the National Basic Research Program of China under Grant No 2013CB632801the National Key Research and Development Program under Grant No 2016YFB0402303+2 种基金the National Natural Science Foundation of China under Grant Nos61435014,61627822,61574136 and 61306058the Key Projects of Chinese Academy of Sciences under Grant No ZDRW-XH-2016-4the Beijing Natural Science Foundation under Grant No 4162060
文摘We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.
基金financially supported in part by the National Science Council,Republic of China,under contract MOST 110-2221-E-006-183-supported by Taipower and RCETS offshore wind power team.
文摘As the increasing number of wind energy is integrated into the national power grid,analyses of wind energy are becoming increasingly more crucial.The interaction between the topography and the northeast(NE)monsoon brings abundant wind resources to the Taiwan Strait in autumn and winter.The offshore area has stronger and more stable wind resources,so deployment of offshore wind power is also actively being carried out.However,development of offshore wind power systems requires stricter evaluation and decision-making.Therefore,this study implements a multi-site measurement verification to establish the relationship between the wind resources of the nearshore wind turbine system and a potential offshore power site in Chanbin.In the absence of a wind turbine at a specific location,potential of offshore wind energy is analyzed through wind resources.The findings showed that although the distance between these two sites is substantial,the nearshore and offshore areas at Chanbin experience similar wind conditions,and nearshore wind turbine can respond well to changes in wind speed and generate power accordingly.Afterwards,on this basis,the offshore power potential was evaluated and compared with the nearshore wind turbine systems.The results suggested the advantages of offshore wind power.A further analysis of the differences between power generation on a monthly basis was carried out to determine the distribution of wind turbine operation modes and illustrate the influence of the NE monsoon.
文摘This study proposes a novel combined primary and secondary control approach for direct current microgrids,specifi-cally in islanded mode.In primary control,this approach establishes an appropriate load power sharing between the distributed energy resources based on their rated power.Simultaneously,it considers the load voltage deviation and provides satisfactory voltage regulation in the secondary control loop.The proposed primary control is based on an efficient droop mechanism that only deploys the local variable measurements,so as to overcome the side effects caused by communication delays.In the case of secondary control,two different methods are devised.In the first,low bandwidth communication links are used to establish the minimum required data transfer between the converters.The effect of communication delay is further explored.The second method excludes any communication link and only uses local variables.Accordingly,a self-sufficient control loop is devised without any communication require-ment.The proposed control notions are investigated in MATLAB/Simulink platform to highlight system performance.The results demonstrate that both proposed approaches can effectively compensate for the voltage deviation due to the primary control task.Detailed comparisons of the two methods are also provided.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10576012 and 60538010.
文摘The mode-area scaling properties of helical-core optical fibres are numerically studied and the limit of core size for achievable single-mode operation is explored. By appropriate design, helical-core fibres can operate in a single mode with possible scaling up to 300μm in core diameter with numerical aperture 0.1.
文摘为研究兆瓦级高效紧凑型核动力系统的运行特性,使用自主开发的热管堆瞬态分析程序TAPIRS(Transient Analysis code for heat Pipe and AMTEC power conversion space Reactor power System)和超临界二氧化碳布雷顿循环的瞬态分析程序SCTRAN/CO_(2)(Super Critical reactors Transient Analysis code/Carbon Dioxide)的耦合程序对其反应性、负荷、冷却水温度和流量等扰动进行了开环动态响应分析,并据此进行了控制系统设计。在此基础上,对线性变负荷、阶梯式变负荷以及甩负荷这三种变负荷运行工况进行了计算分析。结果表明:该核动力系统的转速对扰动的变化较为敏感,需要加以控制;低负荷下旁通会使压缩机流量上升,需对压缩机流量加以控制;系统在控制方案下能以6%FP(Full Power)·min^(−1)的速度实现0%~100%的负荷变动,且可以在任意负荷水平下运行;甩负荷下系统的波动时间变长,但是仍可达到新的稳态进行工作,且各参数处于安全范围内。本研究可为新型核动力系统的概念设计提供参考。