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基于Power BI的绿色供应链环境成本管理研究 被引量:2
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作者 潘富玲 符丽美 《财会通讯》 北大核心 2025年第2期169-176,共8页
一味追求经济利益而忽略环境因素将不利于企业实现绿色可持续发展目标,同时也与当前国家大力号召的绿色低碳转型产业方向相背离。传统末端治理方法会导致事后阶段环境成本的比重不断增加,进而使企业面临着巨大的双重压力即经济和环境污... 一味追求经济利益而忽略环境因素将不利于企业实现绿色可持续发展目标,同时也与当前国家大力号召的绿色低碳转型产业方向相背离。传统末端治理方法会导致事后阶段环境成本的比重不断增加,进而使企业面临着巨大的双重压力即经济和环境污染治理负担。如何有效提升公司的环境成本管理效率和效果成为环保机构、企业及社会各界关注的重点问题。企业环境成本产生于绿色供应链各环节之中,为进一步提高绿色供应链环境成本管理的透明度、实时性、效率性,引入具有数据集中、数据预处理、结果直观可视化功能的Power BI技术,结合高污染、高耗能的钢铁行业企业展开具体分析。研究发现,利用Power BI实现各供应链环节之中的环境成本情况明晰化,进而通过提升每个环节的绿色化能够有效降低企业环境成本,减少环境污染问题。 展开更多
关键词 绿色供应链 环境成本管理 power BI
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Microwave power transmission technologies for space solar power station
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作者 YANG Bo SHINOHARA Naoki 《中国空间科学技术(中英文)》 北大核心 2025年第2期1-14,共14页
The microwave wireless power transmission technologies for space solar power station are a crucial field in the international space sector,where various countries are competing in its development.This paper surveys th... The microwave wireless power transmission technologies for space solar power station are a crucial field in the international space sector,where various countries are competing in its development.This paper surveys the research experiments and development efforts related to space solar power stations and microwave wireless power transmission technologies worldwide.The objective is to assess the progress and current state of this technological foundation,determine the necessary focus for developing high-power microwave wireless power transmission technology,and provide clarity on the direction of future technology development in these areas.Finally,a distributed space solar power station plan that is immediately feasible is proposed. 展开更多
关键词 microwave power transmission space solar power station wireless power transfer microwave transmitter phased array rectenna array
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Multi-objective optimization of microwave power transmission system architecture with engineering consideration
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作者 DONG Shiwei SHINOHARA Naoki 《中国空间科学技术(中英文)》 北大核心 2025年第4期114-122,共9页
In the last decade,space solar power satellites(SSPSs)have been conceived to support net-zero carbon emissions and have attracted considerable attention.Electric energy is transmitted to the ground via a microwave pow... In the last decade,space solar power satellites(SSPSs)have been conceived to support net-zero carbon emissions and have attracted considerable attention.Electric energy is transmitted to the ground via a microwave power beam,a technology known as microwave power transmission(MPT).Due to the vast transmission distance of tens of thousands of kilometers,the power transmitting antenna array must span up to 1 kilometer in diameter.At the same time,the size of the rectifying array on the ground should extend over a few kilometers.This makes the MPT system of SSPSs significantly larger than the existing aerospace engineering system.To design and operate a rational MPT system,comprehensive optimization is required.Taking the space MPT system engineering into consideration,a novel multi-objective optimization function is proposed and further analyzed.The multi-objective optimization problem is modeled mathematically.Beam collection efficiency(BCE)is the primary factor,followed by the thermal management capability.Some tapers,designed to solve the conflict between BCE and the thermal problem,are reviewed.In addition to these two factors,rectenna design complexity is included as a functional factor in the optimization objective.Weight coefficients are assigned to these factors to prioritize them.Radiating planar arrays with different aperture illumination fields are studied,and their performances are compared using the multi-objective optimization function.Transmitting array size,rectifying array size,transmission distance,and transmitted power remaine constant in various cases,ensuring fair comparisons.The analysis results show that the proposed optimization function is effective in optimizing and selecting the MPT system architecture.It is also noted that the multi-objective optimization function can be expanded to include other factors in the future. 展开更多
关键词 space solar power satellite(SSPS) microwave power transmission(MPT) multi-objective function beam collection efficiency(BCE) system engineering
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An optimal design of the liquid-cooling plate channel in a power battery based on response surface methodology
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作者 Jinbo Zheng Jibin Jiang +2 位作者 Xiwei Yu Bingjun Yan Guofu Lian 《中国科学技术大学学报》 北大核心 2025年第2期52-65,51,I0002,共16页
The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the rel... The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters. 展开更多
关键词 response surface methodology power battery cooling channel optimal design
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A class of quasilinear equations with-1 powers
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作者 ZHANG Heng SUN Yijing 《中国科学院大学学报(中英文)》 北大核心 2025年第1期13-19,共7页
This paper deals with quasilinear elliptic equations of singular growth like-Δu-uΔ(u^(2))=a(x)u^(-1).We establish the existence of positive solutions for general a(x)∈L^(p)(Ω),p>2,whereΩis a bounded domain inℝ... This paper deals with quasilinear elliptic equations of singular growth like-Δu-uΔ(u^(2))=a(x)u^(-1).We establish the existence of positive solutions for general a(x)∈L^(p)(Ω),p>2,whereΩis a bounded domain inℝ^(N)with N≥1. 展开更多
关键词 quasilinear singular equation -1 power elliptic equation
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Discussion on Methods and Influence Factors for Minimum Propulsion Power Assessment
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作者 ZHAN Xing−yu MAO Xiao−fei LI Ting−qiu 《船舶力学》 北大核心 2025年第6期888-900,共13页
Currently,the International Maritime Organization(IMO)has approved and implemented the assessment requirement for Minimum Propulsion Power(MPP)of ships in adverse sea conditions.The assessment method and relevant infl... Currently,the International Maritime Organization(IMO)has approved and implemented the assessment requirement for Minimum Propulsion Power(MPP)of ships in adverse sea conditions.The assessment method and relevant influence factors will have a vital impact on ship's design and operation.On the other hand,MPP is essentially a criterion for manoeuvring safety at actual seas.However,the practical assessment methods adopted in IMO guidelines do not directly and accurately account for ship's coursekeeping ability in severe seas.A time-domain comprehensive method with supplementary course-keeping ability criteria has been proposed in the authors'preliminary research.Based on an updated mathematical model and criteria,this paper presents more detailed elaborations,results and discussions on the time-domain method,including the comparative analyses with a power line method and two steady-state equilibrium methods based on IMO guidelines and draft.Discussions on the influences of key factors,involving criterion conditions and calculation parameters,are also presented.The results indicate that different methods exhibit varying advantages and complexity in MPP assessment,thus constituting a multi-level assessment framework for MPP.In particular,the time-domain comprehensive assessment has a higher accuracy with more realistic description of manoeuvre behaviors,capable of offering a solution for the ships that cannot meet other assessments,or for the assessment requiring additional course-keeping ability.Furthermore,an expanded range of wave direction sets a stricter but potentially necessary requirement,while using the self-propulsion factors at low speeds can eliminate the unnecessary conservation of assessment result caused by those at design speed. 展开更多
关键词 manoeuvrability in actual seas minimum propulsion power comprehensive assessment manoeuvrability criterion course keeping
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Study, development and related application of a miniature compact pulsed power supply with high repetition frequency
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作者 Zhangfei Wang Jian Liu +1 位作者 Chunxia Yang Baoming Li 《Defence Technology(防务技术)》 2025年第5期304-318,共15页
Capacitor-based pulsed power supply(PPS)is widely used in fields related to electromagnetic launch,plasma,and materials'synthesis,modification and processing.As industrial applications place higher requirements on... Capacitor-based pulsed power supply(PPS)is widely used in fields related to electromagnetic launch,plasma,and materials'synthesis,modification and processing.As industrial applications place higher requirements on compact and portable pulsed power supplies,the National Key Laboratory of Transient Physics(NKLTP)recently developed a pulsed power supply consisting of a set of compact pulse-forming units(PFU),each with a capacitor energy storage of 220 kJ.This integrated PPS comes with a complete system configuration,a miniature compact structure,a high rate of repetition,and high power,with energy storage density exceeding 1.2 MJ/m^(3).This paper describes the device-level design of the unit,the system layout,the control system,the thermal management system,and the experimental results of the pulsed power supply.The experimental results verified the good reliability of the PPS at high repetition rates with each unit module delivering an output current of more than 100 kA.Additionally,flexible current pulse shapes can be formed by setting the charging voltage and the trigger sequence of the PFUs.The pulse forming network(PFN)developed from these PFUs was successfully applied to electromagnetic launch. 展开更多
关键词 Electromagnetic railgun Pulsed power supply Energy storage density Thermal management system Precision control system
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Optimal Receiver Operating Characteristic Curve of Classical Conditional Power under Normal Models
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作者 ZHANG Ying-Ying 《应用概率统计》 北大核心 2025年第2期277-304,共28页
A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment ... A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment effect and interim result.For hypotheses and reversed hypotheses under normal models,we obtain analytical expressions of the ROC curves of the CCP,find optimal ROC curves of the CCP,investigate the superiority of the ROC curves of the CCP,calculate critical values of the False Positive Rate(FPR),True Positive Rate(TPR),and cutoff of the optimal CCP,and give go/no go decisions at the interim of the optimal CCP.In addition,extensive numerical experiments are carried out to exemplify our theoretical results.Finally,a real data example is performed to illustrate the go/no go decisions of the optimal CCP. 展开更多
关键词 area under the curve(AUC) classical conditional power(CCP) go/no go decisions historical and interim data receiver operating characteristic(ROC)curve
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Power-V诱导的钻柱黏滑振动特征分析 被引量:1
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作者 王文昌 段浩宇 +2 位作者 李宁 王孝亮 狄勤丰 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期299-307,共9页
黏滑是石油钻井过程中影响钻井效率和井下钻柱安全的一种振动形式.垂直钻井系统Power-V在提供有效控斜力的同时,还会诱导钻柱黏滑振动.通过研究垂直钻井系统Power-V与井壁的接触作用及钻头与地层的相互作用模型,基于钻柱动力学有限元方... 黏滑是石油钻井过程中影响钻井效率和井下钻柱安全的一种振动形式.垂直钻井系统Power-V在提供有效控斜力的同时,还会诱导钻柱黏滑振动.通过研究垂直钻井系统Power-V与井壁的接触作用及钻头与地层的相互作用模型,基于钻柱动力学有限元方法,深入分析Power-V的作用机理,研究其对扭转振动的影响,指出Power-V和井壁间的相互作用会导致钻柱与井壁的摩阻显著增加,进而引起摩阻扭矩的增大,诱导井下黏滑振动.实测振动数据证实,Power-V与井壁间的相互作用是引起钻柱黏滑振动的关键因素.这对于揭示黏滑振动的成因和更好地发挥Power-V的作用具有重要意义. 展开更多
关键词 黏滑振动 钻柱动力学 振动信号测量 power-V
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Research on Verification Method of Motor Startups in Nuclear Power Plants Based on Topology Recognition
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作者 Li Baozhu Dong Weijie Chen Chao 《系统仿真学报》 CAS CSCD 北大核心 2024年第12期2813-2823,共11页
There are many motors in operation or on standby in nuclear power plants,and the startup of group motors will have a great impact on the voltage of the emergency bus.At present,there is no special or inexpensive softw... There are many motors in operation or on standby in nuclear power plants,and the startup of group motors will have a great impact on the voltage of the emergency bus.At present,there is no special or inexpensive software to solve this problem,and the experience of engineers is not accurate enough.Therefore,this paper developed a method and system for the startup calculation of group motors in nuclear power plants and proposed an automatic generation method of circuit topology in nuclear power plants.Each component in the topology was given its unique number,and the component class could be constructed according to its type and upper and lower connections.The subordination and topology relationship of switches,buses,and motors could be quickly generated by the program according to the component class,and the simplified direct power flow algorithm was used to calculate the power flow for the startup of group motors according to the above relationship.Then,whether the bus voltage is in the safe range and whether the voltage exceeds the limit during the startup of the group motor could be judged.The practical example was used to verify the effectiveness of the method.Compared with other professional software,the method has high efficiency and low cost. 展开更多
关键词 power supply for nuclear power plant automatic topology recognition startup of group motor simplified direct power flow algorithm verification method
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A review on recent development of space solar power
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作者 HOU Xinbin MANKINS John +2 位作者 SHINOHARA Naoki CHOI Joon-Min SOLTAU Martin 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第6期33-51,共19页
Space solar power(SSP)system,a major type of space-based power-generating equipment,is an important infrastructure providing massive,continuous,and stable green electricity by utilizing solar energy in space.Many coun... Space solar power(SSP)system,a major type of space-based power-generating equipment,is an important infrastructure providing massive,continuous,and stable green electricity by utilizing solar energy in space.Many countries and organizations consider SSP to be one of the most promising clean energy sources.The historical activities of SSP in the world are summarized.This review focuses on the significant development of SSP during the last 10 years,which is the most important period for SSP.The latest international SSP development programmes in the United States,ESA,Japan,China,UK and Korea are presented.Some significant solar power satellite(SPS)concepts proposed in the decade,including typical SPS-ALPHA,MR-SPS,CASSIOPeiA SPS,et al.,are introduced.The technical and non-technical challenges are also listed and several important in-space demonstration missions in recent years and in the near future are introduced.The conclusion is that the next 5 to 10 years will be an important period for rapidly developing the key technologies and conducting on-orbit demonstration and application.Controlling the mutual position relationship between the solar array and the transmitting antenna becomes a core issue to be considered in the innovative design of the SPS.Wireless power transmission technologies would be the demonstration focus for the first step.It is expected that the first commercial SPS would be constructed as early as 2040. 展开更多
关键词 space solar power solar power satellite REVIEW STRATEGY DEMONSTRATION
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Comparison of the Overall CO_(2) Emissions of Different Powertrain Systems Depending on the Energy Sector Emissions
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作者 Tobias STOLL Hans-Jürgen BERNER AndréCASAL KULZER 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期46-50,共5页
A circular and sustainable economy for the private transport sector requires a holistic view of the emitted CO_(2) emissions.Looking at the energy supplied to the vehicle in terms of a circular economy leads to defoss... A circular and sustainable economy for the private transport sector requires a holistic view of the emitted CO_(2) emissions.Looking at the energy supplied to the vehicle in terms of a circular economy leads to defossilisation.The remaining energy sources or forms are renewable electric energy,green hydrogen and renewable fuels.A holistic view of the CO_(2) emissions of these energy sources and forms and the resulting powertrain technologies must take into account all cradle-to-grave emissions for both the vehicle and the energy supply.In order to compare the different forms of energy,the three most relevant forms of powertrain technology are considered and a configuration is chosen that allows for an appropriate comparison.For this purpose,data from the FVV project“Powertrain 2040”are used[1]and combined with research data on the energy supply chain for passenger cars.The three comparable powertrain configurations are a battery electric vehicle,a fuel cell electric vehicle and an internal combustion engine hybrid vehicle fueled with electric fuel.First,the three selected powertrain configurations are presented in terms of their performance,weight,technology and other characteristics.A comparative analysis is carried out for different CO_(2) emissions of the electricity mix.The electricity mix is used for both the production of the vehicle and the energy.The results are presented in the form of cradle-to-wheel emissions,which consider the total CO_(2) emissions of the vehicle over its life cycle.Finally,the results are analyzed and discussed to determine which powertrain technology fits best into which energy sector CO_(2) emissions window. 展开更多
关键词 VEHICLES energy supply power system carbon emission
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电力多元转换(Power-to-X):技术路径、应用与挑战 被引量:5
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作者 李亚楼 王丹丹 +1 位作者 赵飞 李芳 《电网技术》 EI CSCD 北大核心 2024年第5期1809-1820,I0001,共13页
碳中和目标驱动下,新能源装机比重迅速提升,但其随机性与波动性将给电力系统消纳和安全运行带来巨大挑战。电力多元转换(Power-to-X)可以将可再生能源发电转换为其他各类绿色燃料,利用化学能实现对电能的吸收、储存和运输,为电力系统电... 碳中和目标驱动下,新能源装机比重迅速提升,但其随机性与波动性将给电力系统消纳和安全运行带来巨大挑战。电力多元转换(Power-to-X)可以将可再生能源发电转换为其他各类绿色燃料,利用化学能实现对电能的吸收、储存和运输,为电力系统电能储存和利用提供了新思路;同时,通过电力多元转换,也加强了各种能源形式的耦合,降低了不同领域的碳排放,对推进我国绿色低碳转型具有重要意义。该文着重介绍了Power-to-X涉及的各个关键环节,包括电解制储氢、碳捕集以及绿氢转换的技术发展现状;重点比较了4类典型Power-to-X路径——电转甲烷、电转甲醇、电转醚类和电转氨的技术流程;此外,该文针对当前国内外Power-to-X实施情况,具体介绍了各类示范项目的应用进展;进一步地,该文从能效、碳源以及制氢技术等方面出发,剖析了Power-to-X发展面临的主要问题与挑战;最后,针对当前问题,该文提出了相应应对措施,并对Power-to-X的未来发展进行了展望。 展开更多
关键词 可再生能源 电力多元转换 电解制氢 绿氢转换 绿色燃料
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Modified multiple-component scattering power decomposition for PolSAR data based on eigenspace of coherency matrix
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作者 ZHANG Shuang WANG Lu WANG Wen-Qing 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第4期572-581,共10页
A modified multiple-component scattering power decomposition for analyzing polarimetric synthetic aperture radar(PolSAR)data is proposed.The modified decomposition involves two distinct steps.Firstly,ei⁃genvectors of ... A modified multiple-component scattering power decomposition for analyzing polarimetric synthetic aperture radar(PolSAR)data is proposed.The modified decomposition involves two distinct steps.Firstly,ei⁃genvectors of the coherency matrix are used to modify the scattering models.Secondly,the entropy and anisotro⁃py of targets are used to improve the volume scattering power.With the guarantee of high double-bounce scatter⁃ing power in the urban areas,the proposed algorithm effectively improves the volume scattering power of vegeta⁃tion areas.The efficacy of the modified multiple-component scattering power decomposition is validated using ac⁃tual AIRSAR PolSAR data.The scattering power obtained through decomposing the original coherency matrix and the coherency matrix after orientation angle compensation is compared with three algorithms.Results from the experiment demonstrate that the proposed decomposition yields more effective scattering power for different PolSAR data sets. 展开更多
关键词 PolSAR data model-based decomposition eigenvalue decomposition scattering power
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Numerical simulation on magnetohydrodynamic power generation channel of scramjet
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作者 LING Wenhui WU Shaoxun +2 位作者 ZHANG Yining LIU Chenyuan MENG Hao 《推进技术》 EI CAS CSCD 北大核心 2024年第11期255-268,共14页
The reverse magnetohydrodynamic(MHD)energy bypass technology is a promising energy redis⁃tribution technology in the scramjet system,in augmented with a power generation equipment to supply the neces⁃sary long-distanc... The reverse magnetohydrodynamic(MHD)energy bypass technology is a promising energy redis⁃tribution technology in the scramjet system,in augmented with a power generation equipment to supply the neces⁃sary long-distance flight airframe power.In this paper,a computational model of the scramjet magnetohydrody⁃namic channel is developed and verified by using the commercial software Fluent.It is found that when the mag⁃netic induction intensity is 1,2,3,4 T,the power generation efficiency is 22.5%,22.3%,22.0%,21.5%,and decreases with the increase of the magnetic induction intensity,and the enthalpy extraction rate is 0.026%,0.1%,0.21%,0.34%,and increases with the increase of the magnetic induction intensity.The deceleration ef⁃fect of electromagnetic action on the airflow in the power channel increases with the increase of magnetic induc⁃tion intensity.The stronger the magnetic field intensity,the more obvious the decreasing effect of fluid Mach num⁃ber in the channel.The power generation efficiency decreases as the magnetic induction intensity increases and the enthalpy extraction rate is reversed.As the local currents gathering at inlet and outlet of the power generation area,total temperature and enthalpy along the flow direction do not vary linearly,and there are maximum and minimum values at inlet and outlet.Increasing the number of electrodes can effectively regulate the percentage of Joule heat dissipation,which can improve the power generation efficiency. 展开更多
关键词 SCRAMJET MAGNETOHYDRODYNAMICS power generation channel Ionized seeds Numerical simulation
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规模新能源接入场景下计及灵活性资源协同均衡的电力系统黑启动动态分区方法 被引量:2
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作者 刘艳 袁可心 +2 位作者 顾雪平 刘玉田 王洪涛 《中国电机工程学报》 北大核心 2025年第6期2084-2096,I0004,共14页
研究规模新能源接入场景下的黑启动动态分区策略对于提升电力应急保障能力、助力电力系统安全低碳转型具有重要意义。该文计及灵活性资源均衡约束,建立了最大化分区凝聚度和机组加权发电量以及最小化子系统重构进度差异的黑启动动态分... 研究规模新能源接入场景下的黑启动动态分区策略对于提升电力应急保障能力、助力电力系统安全低碳转型具有重要意义。该文计及灵活性资源均衡约束,建立了最大化分区凝聚度和机组加权发电量以及最小化子系统重构进度差异的黑启动动态分区多目标混合整数线性规划模型。基于收缩时域预测控制方法建立黑启动动态分区滚动优化框架,进一步采用广义Benders分解,通过机组分区主问题与系统分区子问题的交互迭代实现模型求解。最后,以接入规模风电和储能的IEEE 39节点系统和IEEE 118节点系统的仿真结果表明:所提方法通过分区优化过程中灵活性资源的协同均衡支撑新能源机组的运行安全,实现系统分区重构过程对新能源机组出力的高效利用,有效提升了系统重建效率。 展开更多
关键词 新型电力系统 黑启动 动态分区 规模风电 灵活性资源 收缩时域预测控制
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面向幂律图的动态图存储结构Power-PCSR
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作者 毛志雄 刘志楠 +3 位作者 高叙宁 王蒙湘 巩树凤 张岩峰 《计算机科学》 CSCD 北大核心 2024年第8期56-62,共7页
图数据在现实生活中广泛存在,且不断发生变化。传统高效的静态图存储方式——压缩行/列(Compressed Sparse Row/Column,CSR/CSR)存储方式在更新图数据时需要大量的数据迁移,不适用于动态图数据。而能够高效更新图数据的邻接表(Adjacency... 图数据在现实生活中广泛存在,且不断发生变化。传统高效的静态图存储方式——压缩行/列(Compressed Sparse Row/Column,CSR/CSR)存储方式在更新图数据时需要大量的数据迁移,不适用于动态图数据。而能够高效更新图数据的邻接表(Adjacency List,AL)存储方式往往带有大量的指针,导致其图数据读取和分析效率低。Packed Compressed Sparse Row(PCSR)是一种基于CSR的动态图存储结构。该结构在存储边数据时并不是采用连续无空隙数组,而是采用留有空槽的压缩存储阵列(Packed Memory Arrays,PMA)结构,便于边数据的插入。因此,PCSR支持高效图更新和图分析。但是,PCSR在存储幂律图时,其性能容易受大度数顶点的影响。为此,基于PCSR提出一种支持可高效更新和分析动态幂律图的图存储结构Power-PCSR。该结构将幂律图中度数较大的顶点单独存储在一个独立的PMA中,其他所有小度数顶点与PCSR一样存储在原PMA中。小度顶点变化导致的数据迁移不会触及大度数顶点,从而大大减少了数据迁移数量;同样,大度数顶点更新导致的数据迁移只限制在每个大度数顶点的PMA内部,不会涉及小度数顶点和其他大度数顶点的数据迁移。实验显示,Power-PCSR在分析图数据时与PCSR具有相似的性能,而在更新图数据时比PCSR快2倍。 展开更多
关键词 动态图存储 动态图更新 数据迁移 power-PCSR 幂律图
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碳中和背景下基于边缘节点技术的电力系统转型研究 被引量:2
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作者 李金 高红亮 +1 位作者 刘科孟 谢虎 《电测与仪表》 北大核心 2025年第4期10-18,共9页
电力系统接入多种新能源后,主要采用源-荷平衡技术,进行电力系统转型,使得转型后系统碳排放量过高。因此,提出碳中和背景下基于边缘节点技术的电力系统转型研究。根据电力系统历史数据建立平稳时间序列,再通过指数法平滑法预测中长期电... 电力系统接入多种新能源后,主要采用源-荷平衡技术,进行电力系统转型,使得转型后系统碳排放量过高。因此,提出碳中和背景下基于边缘节点技术的电力系统转型研究。根据电力系统历史数据建立平稳时间序列,再通过指数法平滑法预测中长期电力需求,作为系统转型设计的基础。在碳中和背景下,以最小新能源弃电量为目标,构建新型电力系统规划模型,并提出碳排放和电力平衡约束。运用边缘节点技术,将整个配电系统划分为多个孤岛,每个孤岛内采用改进粒子群算法对电力任务进行合理分配,形成以源-网-荷-储协调规划为核心的新型电力系统。最后,在大数据理论的支撑下,明确新型电力系统运行模式。应用分析结果表明:运用所提转型方法得出的新型电力系统,与转型前电力系统相比,碳排放量减少了42.86%,满足碳中和发展目标。所提系统经过了曼-肯德尔法的检验,具有一定的有效性与可靠性,能够为电力系统转型提供借鉴的应用价值。 展开更多
关键词 碳中和 边缘节点技术 新型电力系统 电力需求预测 协作分配 可再生能源
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适应新型电力系统的电力互替品市场——(三)体系设计 被引量:2
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作者 何光宇 肖居承 +3 位作者 范帅 严正 刘敦楠 李祖毅 《电力系统自动化》 北大核心 2025年第1期80-91,共12页
针对能源转型背景下优化电力市场总体设计的紧迫需求,文中立足于电能价值这一根本点,提出了适应新型电力系统的电力互替品市场体系设计。首先,分析指出电力互替品市场体系的建设目标,正是为了适应低发电边际成本、高系统消纳成本的新能... 针对能源转型背景下优化电力市场总体设计的紧迫需求,文中立足于电能价值这一根本点,提出了适应新型电力系统的电力互替品市场体系设计。首先,分析指出电力互替品市场体系的建设目标,正是为了适应低发电边际成本、高系统消纳成本的新能源,其短期目标是提升系统的调节能力,长期愿景是促使系统具有低调节边际成本。其次,基于对电能价值内涵的再思考,提出了电能双重价值理论,揭示了电能作为商品所具有的生产使用价值和电力电量平衡价值,强调不应基于资源类型而应基于所发挥价值来划分市场主体类型。最后,从商品属性、时间尺度和空间范围等多个维度,对电力互替品市场体系进行了系统设计。该体系由电能量市场、辅助服务市场两大部分构成,其中,前者又可分为互替电量市场与调节电量市场两部分,分别用于反映电能的生产使用价值和平衡价值。在此基础上,对电力互替品市场体系下多区域电力互替品市场形态以及零售商参与电力互替品批发市场的方式进行了探讨。所提出的电力互替品市场体系围绕系统连续平衡而设计,有利于建立公平交易、充分竞争、简单透明的交易机制。 展开更多
关键词 电力市场 电力互替品 新型电力系统 电能双重价值 互替电量 调节电量 新能源消纳
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计及电力-通信-交通耦合网络不确定性的虚拟电厂鲁棒优化调度 被引量:1
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作者 潘超 李梓铭 +3 位作者 龚榆淋 叶宇鸿 孙中伟 周振宇 《电工技术学报》 北大核心 2025年第15期4755-4769,共15页
电力-通信-交通耦合网络中,虚拟电厂(VPP)通过先进的控制、通信、信息采集技术对分布式资源进行规模化聚合调控并积极响应电网需求,能够提高电网运行的稳定性。然而,现有VPP优化调度方法忽略了电力-通信-交通耦合网络中不确定性因素对VP... 电力-通信-交通耦合网络中,虚拟电厂(VPP)通过先进的控制、通信、信息采集技术对分布式资源进行规模化聚合调控并积极响应电网需求,能够提高电网运行的稳定性。然而,现有VPP优化调度方法忽略了电力-通信-交通耦合网络中不确定性因素对VPP需求响应优化调度的影响,导致调度成本高、鲁棒性差。针对上述问题,首先,该文构建电力-通信-交通耦合网络模型,并以最小化网损、节点电压偏差、VPP经济成本的加权和为目标建立优化问题;其次,分析来自电力-通信-交通三个网络的不确定性因素,并构建计及电力-通信-交通耦合网络不确定性的VPP鲁棒优化调度问题;然后,提出一种基于联邦对抗深度Q网络(DQN)的VPP鲁棒优化调度求解算法,通过双智能体之间的不断迭代,实现鲁棒最优策略的对抗求解;最后,对所提算法进行仿真验证,仿真结果表明,所提算法能够有效降低不确定性因素对VPP优化调度的影响,提高电网运行的可靠性与稳定性。 展开更多
关键词 电力-通信-交通 虚拟电厂 不确定性 鲁棒优化调度 联邦对抗深度Q网络(DQN)
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