Molecular dynamics simulations were carried out to study the configuration energy and radial distribution functions of mmonium dihydrogen phosphate solution at different temperatures. The dihydrogen phosphate ion was ...Molecular dynamics simulations were carried out to study the configuration energy and radial distribution functions of mmonium dihydrogen phosphate solution at different temperatures. The dihydrogen phosphate ion was treated as a seven-site model and the ammonium ion was regarded as a five-site model, while a simple-point-charge model for water molecule. An unusually local particle number density fluctuation was observed in the system at saturation temperature. It can be found that the potential energy increases slowly with the temperature from 373 K to 404 K, which indicates that the ammonium dihydrogen phosphate has partly decomposed. The radial distribution function between the hydrogen atom of ammonium cation and the oxygen atom of dihydrogen phosphate ion at three different temperatures shows obvious difference, which indicates that the average H-bond number changes obviously with the temperature. The temperature has an influence on the combination between hydrogen atoms and phosphorus atoms of dihydrogen phosphate ion and there are much more growth units at saturated solutions.展开更多
The high-energy consumption and high construction density of 5G base stations have greatly increased the demand for backup energy storage batteries.To maximize overall benefits for the investors and operators of base ...The high-energy consumption and high construction density of 5G base stations have greatly increased the demand for backup energy storage batteries.To maximize overall benefits for the investors and operators of base station energy storage,we proposed a bi-level optimization model for the operation of the energy storage,and the planning of 5G base stations considering the sleep mechanism.A multi-base station cooperative system composed of 5G acer stations was considered as the research object,and the outer goal was to maximize the net profit over the complete life cycle of the energy storage.Furthermore,the power and capacity of the energy storage configuration were optimized.The inner goal included the sleep mechanism of the base station,and the optimization of the energy storage charging and discharging strategy,for minimizing the daily electricity expenditure of the 5G base station system.Additionally,genetic algorithm and mixed integer programming were used to solve the bi-level optimization model,analyze the numerical example test comparison of the three types of batteries and the net income of the configuration,and finally verify the validity of the model.Furthermore,the sleep mechanism,the charging and discharging strategy for energy consumption,and the economic benefits for the operators were investigated to provide reference for the 5G base station energy storage configuration.展开更多
Compensating for photovoltaic(PV)power forecast errors is an important function of energy storage systems.As PV power outputs have strong random fluctuations and uncertainty,it is difficult to satisfy the grid-connect...Compensating for photovoltaic(PV)power forecast errors is an important function of energy storage systems.As PV power outputs have strong random fluctuations and uncertainty,it is difficult to satisfy the grid-connection requirements using fixed energy storage capacity configuration methods.In this paper,a method of configuring energy storage capacity is proposed based on the uncertainty of PV power generation.A k-means clustering algorithm is used to classify weather types based on differences in solar irradiance.The power forecast errors in different weather types are analyzed,and an energy storage system is used to compensate for the errors.The kernel density estimation is used to fit the distributions of the daily maximum power and maximum capacity requirements of the energy storage system;the power and capacity of the energy storage unit are calculated at different confidence levels.The optimized energy storage configuration of a PV plant is presented according to the calculated degrees of power and capacity satisfaction.The proposed method was validated using actual operating data from a PV power station.The results indicated that the required energy storage can be significantly reduced while compensating for power forecast errors.展开更多
Energy storage is an effective measure to deal with internal power fluctuation of micro-grid and ensure stable operation, especially in the micro-grid with high photovoltaic(PV) penetration. Its capacity configuration...Energy storage is an effective measure to deal with internal power fluctuation of micro-grid and ensure stable operation, especially in the micro-grid with high photovoltaic(PV) penetration. Its capacity configuration is related to the steady, safety and economy of micro-grid.In order to improve the absorptive capacity of micro-grid on maximizing the use of distributed PV power in micro-grid, and improve the power quality, an optimal energy storage configuration strategy is proposed, which takes many factors into account, such as the topology of micro-grid, the change of irradiance, the load fluctuation and the cable. The strategy can optimize the energy storage allocation model to minimize the storage power capacity and optimize the node configuration.The key electrical nodes are identified by using the sensitivity coefficient of the voltage, and then the model is optimized to simplify calculation. Finally, an example of the European low-voltage micro-grid and a micro-grid system in the laboratory is used to verify the effectiveness of the proposed method.The results show that the proposed method can optimize the allocation of capacity and the node of the energy storage system.展开更多
We give a detailed examination of potential energy curves of the singlet and triplet states of CFC1 correlated with the lowest three dissociation limits. The calculations are carried out at the internally contracted m...We give a detailed examination of potential energy curves of the singlet and triplet states of CFC1 correlated with the lowest three dissociation limits. The calculations are carried out at the internally contracted multi- reference configuration interaction/cc-pV(T+d)Z level with the other two geometric parameters fixed at the state equilibrium conformation. The vertical transition energy, the oscillator strength, the main configuration and the electron transition are also investigated at the same level.展开更多
The potential energy curves (PECs) of the 3Π states of GaX (X=F, Cl, and Br) molecules are calculated using the multireference configuration interaction method with a large contracted basis set aug-cc-pV5Z. The P...The potential energy curves (PECs) of the 3Π states of GaX (X=F, Cl, and Br) molecules are calculated using the multireference configuration interaction method with a large contracted basis set aug-cc-pV5Z. The PECs are accurately fitted to analytical potential energy functions (APEFs) using the Murrell–Sorbie potential function. The spectroscopic parameters for the states are determined using the obtained APEFs, and compared with the theoretical and experimental data available presently in the literature.展开更多
China has abundant wind energy resources and huge development potential among developing countries.Japan is a developed country that planned to increase the use of renewable energy,especially wind energy.This research...China has abundant wind energy resources and huge development potential among developing countries.Japan is a developed country that planned to increase the use of renewable energy,especially wind energy.This research is aimed at reviewing the development of wind power and relevant policies between China and Japan.Firstly,we introduced the current status of global wind power development,such as the global installed capacity of wind power.The annual development of wind power generation in China and Japan is compared,and the distribution characteristics of wind resources are compared.Furthermore,the market share in China and Japan is introduced.Finally,according to the comparison of the government policies between China and Japan,we pointed out the existing problems in the wind power industry.In addition,we gave some suggestions on the development of wind power for China and Japan.These suggestions should be taken into account when designing national climate policies and have an important reference value for the future development of China’s wind energy industry.展开更多
Centralized delivery has become the main operation mode under the scaled development of wind power.Transmission channels are usually the guarantee of out-delivered wind power for large-scale wind base.The configuratio...Centralized delivery has become the main operation mode under the scaled development of wind power.Transmission channels are usually the guarantee of out-delivered wind power for large-scale wind base.The configuration of transmission capacity,which has the features of low utilization and poor economy,is hardly matching correctly due to the volatility and low energy density of wind.The usage of energy storage can mitigate wind power fluctuations and reduce the requirement of out-delivery transmission capacity,but facing the issue of energy storage cost recovery.Therefore,it is necessary to optimize the allocation of energy storage while considering the problem of wind power transmission.This paper studies the joint optimization of large-scale wind power transmission capacity and energy storage,reveals the mechanism of energy storage in order to reduce the power fluctuation of wind power base and slow down the demand of transmission.Then,analyze the multi-functional cost-sharing mode of energy storage,improve the efficiency of energy storage cost recovery.Constructs the coordination optimization configuration model to deal with the problem of large-scale wind power transmission capacity and energy storage,and realizes the transmission capacity optimization coordination and optimization with energy storage.The proposed method is verified by a wind base located in Northeast China.展开更多
Core formation by gravitational segregation allegedly released sufficient interior heat to melt the Earth. Analysis of the energetics, which compare gravitational potential energy (Ug) of a fictitious, homogeneous r...Core formation by gravitational segregation allegedly released sufficient interior heat to melt the Earth. Analysis of the energetics, which compare gravitational potential energy (Ug) of a fictitious, homogeneous reference state to Earth's current layered configuration, needs updating to correct errors and omissions, and to accommodate recent findings: (1) An erroneous positive sign was used for Ug while maintaining the reference value of 0 at infinity, which results in an incorrect sign fur AUg, which is crucial in determining whether a process is endothermic or exothermic. (2) The value of Ug for Earth's initial state is uncertain. (3) Recent meteorite evidence indicates that core formation began before the Earth was full-sized, which severely limits AUg. (4) Inhomogeneous accretion additionally reduced AUg. (5) The potentially large effect of differential rotation between the core and the mantle was not accounted for. (6) Entropy changes associated with creating order were neglected. Accordingly, we revise values of Ug, evaluate uncertainties, and show that AUg was converted substantially to eonfigurational energy (TAS). These considerations limit the large sources of primordial heat to impacts and radioactivity. Although these processes may play a role in core formation, their energies are independent of gravitational segregation, which produces order and rotational energy, not internal heat. Instead, gravitational segregation promotes planetary cooling mainly because it segregates lithophilic radioactive elements upward, increasing surface heat flux while shortening the distance over which radiogenic heat diffuses outwards.展开更多
文摘Molecular dynamics simulations were carried out to study the configuration energy and radial distribution functions of mmonium dihydrogen phosphate solution at different temperatures. The dihydrogen phosphate ion was treated as a seven-site model and the ammonium ion was regarded as a five-site model, while a simple-point-charge model for water molecule. An unusually local particle number density fluctuation was observed in the system at saturation temperature. It can be found that the potential energy increases slowly with the temperature from 373 K to 404 K, which indicates that the ammonium dihydrogen phosphate has partly decomposed. The radial distribution function between the hydrogen atom of ammonium cation and the oxygen atom of dihydrogen phosphate ion at three different temperatures shows obvious difference, which indicates that the average H-bond number changes obviously with the temperature. The temperature has an influence on the combination between hydrogen atoms and phosphorus atoms of dihydrogen phosphate ion and there are much more growth units at saturated solutions.
基金supported by the State Grid Science and Technology Project(KJ21-1-56).
文摘The high-energy consumption and high construction density of 5G base stations have greatly increased the demand for backup energy storage batteries.To maximize overall benefits for the investors and operators of base station energy storage,we proposed a bi-level optimization model for the operation of the energy storage,and the planning of 5G base stations considering the sleep mechanism.A multi-base station cooperative system composed of 5G acer stations was considered as the research object,and the outer goal was to maximize the net profit over the complete life cycle of the energy storage.Furthermore,the power and capacity of the energy storage configuration were optimized.The inner goal included the sleep mechanism of the base station,and the optimization of the energy storage charging and discharging strategy,for minimizing the daily electricity expenditure of the 5G base station system.Additionally,genetic algorithm and mixed integer programming were used to solve the bi-level optimization model,analyze the numerical example test comparison of the three types of batteries and the net income of the configuration,and finally verify the validity of the model.Furthermore,the sleep mechanism,the charging and discharging strategy for energy consumption,and the economic benefits for the operators were investigated to provide reference for the 5G base station energy storage configuration.
基金supported by Nation Key R&D Program of China(2021YFE0102400).
文摘Compensating for photovoltaic(PV)power forecast errors is an important function of energy storage systems.As PV power outputs have strong random fluctuations and uncertainty,it is difficult to satisfy the grid-connection requirements using fixed energy storage capacity configuration methods.In this paper,a method of configuring energy storage capacity is proposed based on the uncertainty of PV power generation.A k-means clustering algorithm is used to classify weather types based on differences in solar irradiance.The power forecast errors in different weather types are analyzed,and an energy storage system is used to compensate for the errors.The kernel density estimation is used to fit the distributions of the daily maximum power and maximum capacity requirements of the energy storage system;the power and capacity of the energy storage unit are calculated at different confidence levels.The optimized energy storage configuration of a PV plant is presented according to the calculated degrees of power and capacity satisfaction.The proposed method was validated using actual operating data from a PV power station.The results indicated that the required energy storage can be significantly reduced while compensating for power forecast errors.
基金Supported by the National Program of International S&T Cooperation(No.2014DFE60020)Natural Science Foundation of Zhejiang Province(No.LY15E070004)
文摘Energy storage is an effective measure to deal with internal power fluctuation of micro-grid and ensure stable operation, especially in the micro-grid with high photovoltaic(PV) penetration. Its capacity configuration is related to the steady, safety and economy of micro-grid.In order to improve the absorptive capacity of micro-grid on maximizing the use of distributed PV power in micro-grid, and improve the power quality, an optimal energy storage configuration strategy is proposed, which takes many factors into account, such as the topology of micro-grid, the change of irradiance, the load fluctuation and the cable. The strategy can optimize the energy storage allocation model to minimize the storage power capacity and optimize the node configuration.The key electrical nodes are identified by using the sensitivity coefficient of the voltage, and then the model is optimized to simplify calculation. Finally, an example of the European low-voltage micro-grid and a micro-grid system in the laboratory is used to verify the effectiveness of the proposed method.The results show that the proposed method can optimize the allocation of capacity and the node of the energy storage system.
基金Supported by the National Natural Science Foundation of China under Grant No 11447148
文摘We give a detailed examination of potential energy curves of the singlet and triplet states of CFC1 correlated with the lowest three dissociation limits. The calculations are carried out at the internally contracted multi- reference configuration interaction/cc-pV(T+d)Z level with the other two geometric parameters fixed at the state equilibrium conformation. The vertical transition energy, the oscillator strength, the main configuration and the electron transition are also investigated at the same level.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11174117 and 10974078)the Program for Scientific Research Innova-tion Team in Colleges and Universities of Shandong Province,China
文摘The potential energy curves (PECs) of the 3Π states of GaX (X=F, Cl, and Br) molecules are calculated using the multireference configuration interaction method with a large contracted basis set aug-cc-pV5Z. The PECs are accurately fitted to analytical potential energy functions (APEFs) using the Murrell–Sorbie potential function. The spectroscopic parameters for the states are determined using the obtained APEFs, and compared with the theoretical and experimental data available presently in the literature.
文摘China has abundant wind energy resources and huge development potential among developing countries.Japan is a developed country that planned to increase the use of renewable energy,especially wind energy.This research is aimed at reviewing the development of wind power and relevant policies between China and Japan.Firstly,we introduced the current status of global wind power development,such as the global installed capacity of wind power.The annual development of wind power generation in China and Japan is compared,and the distribution characteristics of wind resources are compared.Furthermore,the market share in China and Japan is introduced.Finally,according to the comparison of the government policies between China and Japan,we pointed out the existing problems in the wind power industry.In addition,we gave some suggestions on the development of wind power for China and Japan.These suggestions should be taken into account when designing national climate policies and have an important reference value for the future development of China’s wind energy industry.
基金supported by the National Key Research and Development Program(2016YFB0900100)。
文摘Centralized delivery has become the main operation mode under the scaled development of wind power.Transmission channels are usually the guarantee of out-delivered wind power for large-scale wind base.The configuration of transmission capacity,which has the features of low utilization and poor economy,is hardly matching correctly due to the volatility and low energy density of wind.The usage of energy storage can mitigate wind power fluctuations and reduce the requirement of out-delivery transmission capacity,but facing the issue of energy storage cost recovery.Therefore,it is necessary to optimize the allocation of energy storage while considering the problem of wind power transmission.This paper studies the joint optimization of large-scale wind power transmission capacity and energy storage,reveals the mechanism of energy storage in order to reduce the power fluctuation of wind power base and slow down the demand of transmission.Then,analyze the multi-functional cost-sharing mode of energy storage,improve the efficiency of energy storage cost recovery.Constructs the coordination optimization configuration model to deal with the problem of large-scale wind power transmission capacity and energy storage,and realizes the transmission capacity optimization coordination and optimization with energy storage.The proposed method is verified by a wind base located in Northeast China.
文摘Core formation by gravitational segregation allegedly released sufficient interior heat to melt the Earth. Analysis of the energetics, which compare gravitational potential energy (Ug) of a fictitious, homogeneous reference state to Earth's current layered configuration, needs updating to correct errors and omissions, and to accommodate recent findings: (1) An erroneous positive sign was used for Ug while maintaining the reference value of 0 at infinity, which results in an incorrect sign fur AUg, which is crucial in determining whether a process is endothermic or exothermic. (2) The value of Ug for Earth's initial state is uncertain. (3) Recent meteorite evidence indicates that core formation began before the Earth was full-sized, which severely limits AUg. (4) Inhomogeneous accretion additionally reduced AUg. (5) The potentially large effect of differential rotation between the core and the mantle was not accounted for. (6) Entropy changes associated with creating order were neglected. Accordingly, we revise values of Ug, evaluate uncertainties, and show that AUg was converted substantially to eonfigurational energy (TAS). These considerations limit the large sources of primordial heat to impacts and radioactivity. Although these processes may play a role in core formation, their energies are independent of gravitational segregation, which produces order and rotational energy, not internal heat. Instead, gravitational segregation promotes planetary cooling mainly because it segregates lithophilic radioactive elements upward, increasing surface heat flux while shortening the distance over which radiogenic heat diffuses outwards.