Based on the lithium-ion battery pure electric vehicle （PEV） application, two capacity types of batteries are applied in thermal characteristic experiments. With the experimental comparison method, battery thermal c...Based on the lithium-ion battery pure electric vehicle （PEV） application, two capacity types of batteries are applied in thermal characteristic experiments. With the experimental comparison method, battery thermal characteristics and heat generation mechanism are studied. Experiments of batteries in cases of different dimensions, batteries with different air cooling velocity and two capacity types of batteries in free convection environment are put forward. Battery heat generation performance, heat dissipation performance and comparison of different capacity types＇ batteries are researched and summarized. Conclusions of battery heat generation and dissipation in PEV applications, important battery thermal management factors and suggestions are put forward.展开更多
While renewable power generation and vehicle electrification are promising solutions to reduce greenhouse gas emissions, it faces great challenges to effectively integrate them in a power grid. The weather-dependent p...While renewable power generation and vehicle electrification are promising solutions to reduce greenhouse gas emissions, it faces great challenges to effectively integrate them in a power grid. The weather-dependent power generation of renewable energy sources, such as Photovoltaic (PV) arrays, could introduce significant intermittency to a power grid. Meanwhile, uncontrolled PEV charging may cause load surge in a power grid. This paper studies the optimization of PEV charging/discharging scheduling to reduce customer cost and improve grid performance. Optimization algorithms are developed for three cases: 1) minimize cost, 2) minimize power deviation from a pre-defined power profile, and 3) combine objective functions in 1) and 2). A Microgrid with PV arrays, bi-directional PEV charging stations, and a commercial building is used in this study. The bi-directional power from/to PEVs provides the opportunity of using PEVs to reduce the intermittency of PV power generation and the peak load of the Microgrid. Simulation has been performed for all three cases and the simulation results show that the presented optimization algorithms can meet defined objectives.展开更多
A new physics scenario to explain PeV neutrinos observed in the IceCube experiment is introduced,with dark matter and dark energy considered.A slowly decaying very heavy fermion with a Pe V mass as the dark matter par...A new physics scenario to explain PeV neutrinos observed in the IceCube experiment is introduced,with dark matter and dark energy considered.A slowly decaying very heavy fermion with a Pe V mass as the dark matter particle is the origin of the PeV neutrinos.They couple to an extremely light field and this light field constitutes the dark energy.展开更多
Background:The increasing penetration of a massive number of plug-in electric vehicles(PEVs)and distributed generators(DGs)into current power distribution networks imposes obvious challenges on power distribution netw...Background:The increasing penetration of a massive number of plug-in electric vehicles(PEVs)and distributed generators(DGs)into current power distribution networks imposes obvious challenges on power distribution network operation.Methods:This paper presents an optimal temporal-spatial scheduling strategy of PEV charging demand in the presence of DGs.The solution is designed to ensure the reliable and secure operation of the active power distribution networks,the randomness introduced by PEVs and DGs can be managed through the appropriate scheduling of the PEV charging demand,as the PEVs can be considered as mobile energy storage units.Results:As a result,the charging demands of PEVs are optimally scheduled temporally and spatially,which can improve the DG utilization efficiency as well as reduce the charging cost under real-time pricing(RTP).Conclusions:The proposed scheduling strategy is evaluated through a series of simulations and the numerical results demonstrate the effectiveness and the benefits of the proposed solution.展开更多
The tiny modification of dispersion relation induced by Lorentz violation(LV)is an essential topic in quantum gravity(QG)theories,which can be magnified into significant effects when dealing with astrophysical observa...The tiny modification of dispersion relation induced by Lorentz violation(LV)is an essential topic in quantum gravity(QG)theories,which can be magnified into significant effects when dealing with astrophysical observations at high energies and long propagation distances.LV would lead to photon decay at high energies;therefore,observations of high-energy photons could constrain LV or even QG theories.The Large High Altitude Air Shower Observatory(LHAASO)is the most sensitive gamma-array instrument currently operating above 100 TeV.Recently,LHAASO reported the detection of 12 sources above 100 TeV with maximum photon energy exceeding 1 PeV.According to these observations,the most stringent restriction is achieved in this study,i.e.,limiting the LV energy scale to 1.7×10^(33) eV,which is over 139,000 times that of the Planck energy,and achieving an improvement of approximately 1.9 orders of magnitude over previous limits.展开更多
可入网电动汽车(plug-in electric vehicle,PEV)近年来发展迅猛,考虑PEV与清洁能源大量并网后的差异性需求,构建兼顾输电网、配电网与用户利益的双层规划模型。上层输电网规划以系统运行成本最小、车主消费最少、弃风弃光惩罚最少、碳...可入网电动汽车(plug-in electric vehicle,PEV)近年来发展迅猛,考虑PEV与清洁能源大量并网后的差异性需求,构建兼顾输电网、配电网与用户利益的双层规划模型。上层输电网规划以系统运行成本最小、车主消费最少、弃风弃光惩罚最少、碳排放总量最小为目标,协同调度火电机组、新能源与PEV出力,实现PEV的时域调度;下层配电网模型以网损最小为目标,通过最优潮流计算实现PEV的空间调度。算例结果表明,对PEV进行有效调度并配合合理的电网规划方案,可降低电网运行成本,提高其对可再生能源的消纳能力。展开更多
文摘Based on the lithium-ion battery pure electric vehicle （PEV） application, two capacity types of batteries are applied in thermal characteristic experiments. With the experimental comparison method, battery thermal characteristics and heat generation mechanism are studied. Experiments of batteries in cases of different dimensions, batteries with different air cooling velocity and two capacity types of batteries in free convection environment are put forward. Battery heat generation performance, heat dissipation performance and comparison of different capacity types＇ batteries are researched and summarized. Conclusions of battery heat generation and dissipation in PEV applications, important battery thermal management factors and suggestions are put forward.
文摘While renewable power generation and vehicle electrification are promising solutions to reduce greenhouse gas emissions, it faces great challenges to effectively integrate them in a power grid. The weather-dependent power generation of renewable energy sources, such as Photovoltaic (PV) arrays, could introduce significant intermittency to a power grid. Meanwhile, uncontrolled PEV charging may cause load surge in a power grid. This paper studies the optimization of PEV charging/discharging scheduling to reduce customer cost and improve grid performance. Optimization algorithms are developed for three cases: 1) minimize cost, 2) minimize power deviation from a pre-defined power profile, and 3) combine objective functions in 1) and 2). A Microgrid with PV arrays, bi-directional PEV charging stations, and a commercial building is used in this study. The bi-directional power from/to PEVs provides the opportunity of using PEVs to reduce the intermittency of PV power generation and the peak load of the Microgrid. Simulation has been performed for all three cases and the simulation results show that the presented optimization algorithms can meet defined objectives.
基金support from the National Natural Science Foundation of China(Nos.11875306 and 12275335)。
文摘A new physics scenario to explain PeV neutrinos observed in the IceCube experiment is introduced,with dark matter and dark energy considered.A slowly decaying very heavy fermion with a Pe V mass as the dark matter particle is the origin of the PeV neutrinos.They couple to an extremely light field and this light field constitutes the dark energy.
基金The National Key Research and Development Program of China(Basic Research Class 2017YFB0903000)Basic Theories and Methods of Analysis and Control of the Cyber Physical Systems for Power Grid,and the Natural Science Foundation of Zhejiang Province(LZ15E070001).
文摘Background:The increasing penetration of a massive number of plug-in electric vehicles(PEVs)and distributed generators(DGs)into current power distribution networks imposes obvious challenges on power distribution network operation.Methods:This paper presents an optimal temporal-spatial scheduling strategy of PEV charging demand in the presence of DGs.The solution is designed to ensure the reliable and secure operation of the active power distribution networks,the randomness introduced by PEVs and DGs can be managed through the appropriate scheduling of the PEV charging demand,as the PEVs can be considered as mobile energy storage units.Results:As a result,the charging demands of PEVs are optimally scheduled temporally and spatially,which can improve the DG utilization efficiency as well as reduce the charging cost under real-time pricing(RTP).Conclusions:The proposed scheduling strategy is evaluated through a series of simulations and the numerical results demonstrate the effectiveness and the benefits of the proposed solution.
基金Supported in China by National Key R&D program of China(2018YFA0404201)National Science Foundation of China(NSFC)(12022502)。
文摘The tiny modification of dispersion relation induced by Lorentz violation(LV)is an essential topic in quantum gravity(QG)theories,which can be magnified into significant effects when dealing with astrophysical observations at high energies and long propagation distances.LV would lead to photon decay at high energies;therefore,observations of high-energy photons could constrain LV or even QG theories.The Large High Altitude Air Shower Observatory(LHAASO)is the most sensitive gamma-array instrument currently operating above 100 TeV.Recently,LHAASO reported the detection of 12 sources above 100 TeV with maximum photon energy exceeding 1 PeV.According to these observations,the most stringent restriction is achieved in this study,i.e.,limiting the LV energy scale to 1.7×10^(33) eV,which is over 139,000 times that of the Planck energy,and achieving an improvement of approximately 1.9 orders of magnitude over previous limits.
文摘可入网电动汽车(plug-in electric vehicle,PEV)近年来发展迅猛,考虑PEV与清洁能源大量并网后的差异性需求,构建兼顾输电网、配电网与用户利益的双层规划模型。上层输电网规划以系统运行成本最小、车主消费最少、弃风弃光惩罚最少、碳排放总量最小为目标,协同调度火电机组、新能源与PEV出力,实现PEV的时域调度;下层配电网模型以网损最小为目标,通过最优潮流计算实现PEV的空间调度。算例结果表明,对PEV进行有效调度并配合合理的电网规划方案,可降低电网运行成本,提高其对可再生能源的消纳能力。
