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Enhancing Autonomy Capability in Regional Power Grids:A Strategic Planning Approach with Multiple Autonomous Evaluation Indexes
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作者 Jie Ma Tong Zhao +8 位作者 Yuanzhao Hao Wenwen Qin Haozheng Yu Mingxuan Du Yuanhong Liu Liang Zhang Shixia Mu Cuiping Li Junhui Li 《Energy Engineering》 EI 2024年第9期2449-2477,共29页
After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and de... After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network. 展开更多
关键词 Regional autonomous power grid distributed generation distributed energy storage regional planning strategy evaluation index
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The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems
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作者 Caifeng Wen Boxin Zhang +3 位作者 Yuanjun Dai Wenxin Wang Wanbing Xie Qian Du 《Energy Engineering》 EI 2024年第10期2961-2979,共19页
Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different e... Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production. 展开更多
关键词 Wind power system entropy production system losses power quality indexes battery energy storage
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Predicting of Power Quality Steady State Index Based on Chaotic Theory Using Least Squares Support Vector Machine 被引量:2
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作者 Aiqiang Pan Jian Zhou +2 位作者 Peng Zhang Shunfu Lin Jikai Tang 《Energy and Power Engineering》 2017年第4期713-724,共12页
An effective power quality prediction for regional power grid can provide valuable references and contribute to the discovering and solving of power quality problems. So a predicting model for power quality steady sta... An effective power quality prediction for regional power grid can provide valuable references and contribute to the discovering and solving of power quality problems. So a predicting model for power quality steady state index based on chaotic theory and least squares support vector machine (LSSVM) is proposed in this paper. At first, the phase space reconstruction of original power quality data is performed to form a new data space containing the attractor. The new data space is used as training samples for the LSSVM. Then in order to predict power quality steady state index accurately, the particle swarm algorithm is adopted to optimize parameters of the LSSVM model. According to the simulation results based on power quality data measured in a certain distribution network, the model applies to several indexes with higher forecasting accuracy and strong practicability. 展开更多
关键词 CHAOTIC THEORY Least SQUARES Support Vector Machine (LSSVM) power Quality STEADY State index Phase Space Reconstruction Particle SWARM Optimization
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Efficiency Analysis of Listed Power Companies Based on Malmquist Index 被引量:1
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作者 解百臣 吴育华 邓英芝 《Journal of Southwest Jiaotong University(English Edition)》 2008年第1期86-91,共6页
This paper improved the known study for technical progress in Malmquist productivity index calculating. In the method, all the possible movements for decision making units (DMUs) are listed, and the condition that s... This paper improved the known study for technical progress in Malmquist productivity index calculating. In the method, all the possible movements for decision making units (DMUs) are listed, and the condition that several DMUs lie on the productivity frontier is analyzed. The dynamic efficiencies of Chinese listed power companies from 1997 to 2006 were evaluated. The empirical results indicate that the improved method is effective. 展开更多
关键词 Technical Efficiency Malmquist index Listed power company
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Index system and methods for comprehensive assessment of cross-border power grid interconnection projects 被引量:1
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作者 Teng Zhao Yizhe Jiang +4 位作者 Han Jiang Yi Gao Wei Wu Chen Wang Jinxiang Zhu 《Global Energy Interconnection》 CAS 2020年第6期532-544,共13页
With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a c... With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a critical n eed to adopt scie ntific approaches in assessi ng cross-border power grid interconnection projects.First,con sidering the promotion of large-scale renewable energy resources and improvements in system adequacy,a comprehensive assessment index system,including costs,socio-economic benefits,environmental benefits,and technical benefits,is established in this study.Second,a synthetic assessment framework is proposed for cross-border power grid interconnection projects based on the index system comprising cost-benefit analysis,with market and network simulations,iterative methods for indicator weight evaluation,and technique for order preferenee by similarity to an ideal solution(TOPSIS)method for the project rankings.Fin ally,by assessi ng and comparing three cross-border projects betwee n Europe and Asia,the proposed index system and assessment framework have been proved to be effective and feasible;the results of this system can thus support investment decision-making related to such projects in the future. 展开更多
关键词 Cross-border power grid interconnection Comprehensive assessment index system Cost-benefit analysis Iterative method TOPSIS method
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Technical and Economic Index System for CO_2 Emission Reduction in China's Power Industry 被引量:1
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作者 Wu Jiang 《Electricity》 2012年第2期49-54,共6页
The main technic and economic indices for carbon dioxide emission reduction of Chinese electric power industry are designed systematically in this paper.According to quantitative calculation and influential factor ana... The main technic and economic indices for carbon dioxide emission reduction of Chinese electric power industry are designed systematically in this paper.According to quantitative calculation and influential factor analysis on the carbon dioxide emission reduction of the industry from 1978 to 2009,the author estimates and calculates the relevant indices during the 12 th Five-Year Plan period and in 2020.Finally the author analyzes the relationship and difference between the conventional technical and economic indices for electric power planning and the new index system for the low carbon economy development. 展开更多
关键词 electric power industry carbon dioxide emission reduction index
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Research on Security Assessment Index System for Operating Reserve in Large Interconnected Power Grid
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作者 Mingsong Liu Huadong Sun +3 位作者 Jian He Hengxu Zhang Jun Yi Jian Zhang 《Energy and Power Engineering》 2013年第4期785-791,共7页
Optimization and placement of spinning reserve is an important issue in power system planning and operation. Systematic way for security assessment of operating reserve needs to study. A security assessment index syst... Optimization and placement of spinning reserve is an important issue in power system planning and operation. Systematic way for security assessment of operating reserve needs to study. A security assessment index system for operating reserve in large interconnected power grids is presented in this paper. Firstly, classification and determination methods of operating reserve at home and abroad are investigated, and operating reserve is divided into transient state operating reserve and quasi-steady state operating reserve from the view of security assessment. Secondly, assessment indexes and optimization methods for transient state operating reserve are studied. Thirdly, optimization model, deterministic and probabilistic optimization methods for quasi-steady state operating reserve are explored. Finally, some principles for determination of operating reserve are suggested, and a security assessment index system is put forward. The proposed index system, considering both transient and quasi-steady state, both deterministic and probabilistic methods, provides a systematic way to assessment and arrangement of operating reserve. 展开更多
关键词 SECURITY Assessment index System Operating RESERVE SPINNING RESERVE LARGE Interconnected power GRID
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The Wiener Index of an Undirected Power Graph
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作者 Volkan Aşkin Şerife Büyükköse 《Advances in Linear Algebra & Matrix Theory》 2021年第1期21-29,共9页
The undirected power graph <i>P</i>(<i>Z<sub>n</sub></i>) of a finite group <i>Z<sub>n</sub></i> is the graph with vertex set G and two distinct vertices u a... The undirected power graph <i>P</i>(<i>Z<sub>n</sub></i>) of a finite group <i>Z<sub>n</sub></i> is the graph with vertex set G and two distinct vertices u and v are adjacent if and only if <i>u</i> ≠ <i>v</i> and <img src="Edit_3b1df203-9ff2-4c13-93d1-4bba568eae54.png" width="40" height="20" alt="" /> or <img src="Edit_094c8f88-deb6-4f41-825a-ba91c0306ae8.png" width="40" height="20" alt="" />. The Wiener index <i>W</i>(<i>P</i>(<i>Z<sub>n</sub></i>)) of an undirected power graph <i>P</i>(<i>Z<sub>n</sub></i>) is defined to be sum <img src="Edit_348337df-b9c2-480d-9713-ec299a6fcd4e.png" width="110" height="25" alt="" /> of distances between all unordered pair of vertices in <i>P</i>(<i>Z<sub>n</sub></i>). Similarly, the edge-Wiener index <i>W<sub>e</sub></i>(<i>P</i>(<i>Z<sub>n</sub></i>)) of <i>P</i>(<i>Z<sub>n</sub></i>) is defined to be the sum <img src="Edit_e9b89765-f71e-4865-a0c5-c688710ff0c6.png" width="60" height="25" alt="" /> of distances between all unordered pairs of edges in <i>P</i>(<i>Z<sub>n</sub></i>). In this paper, we concentrate on the wiener index of a power graph <img src="Edit_dff0cd99-eb11-4123-a437-78cbbd8ebf96.png" width="40" height="20" alt="" />, <i>P</i>(<i>Z<sub>pq</sub></i>) and <i>P</i>(<i>Z<sub>p</sub></i>). Firstly, we obtain new results on the wiener index and edge-wiener index of power graph <i>P</i>(<i>Z<sub>n</sub></i>), using <i>m,n</i> and Euler function. Also, we obtain an equivalence between the edge-wiener index and wiener index of a power graph of <i>Z<sub>n</sub></i>. 展开更多
关键词 Wiener index Edge-Wiener index An Undirected power Graph Line Graph
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Evaluation method for assessing the auxiliary service transaction mechanism in regional power markets
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作者 Le Liu Xueyu Chen +3 位作者 Dexin Li Chang Liu Dunnan Liu Genzhu Li 《Global Energy Interconnection》 EI CAS CSCD 2023年第2期238-252,共15页
Accurate and seamless auxiliary services in the power market can guarantee smooth and continuous power system operation. China’s new round of power system reform has entered a critical period, and reform implementati... Accurate and seamless auxiliary services in the power market can guarantee smooth and continuous power system operation. China’s new round of power system reform has entered a critical period, and reform implementation requires comprehensive improvements in the maturity of the supporting auxiliary service market. This study reviews the development status and evolution path of the European unified power market and the US regional power market, provides experience for the development of China’s regional power market, then identifies the key influencing factors of auxiliary service trading mechanism design in regional power markets. To analyze the rationality of the auxiliary service trading evaluation index, this paper established an evaluation model for assessing regional power markets. Using combined weight optimization, the gray correlation TOPSIS method was applied to comprehensively evaluate auxiliary service trading in the regional power market. Finally, the application of the proposed evaluation method was briefly analyzed to examine four regional power markets in China and evaluate the effectiveness of current market construction in different regions and provide suggestions for future market construction. 展开更多
关键词 power market Auxiliary services Transaction mechanism Evaluation index Evaluation model
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Major Power Production Indexes Realized in 1996 July
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《Electricity》 1996年第4期54-54,共1页
关键词 Major power Production indexes Realized in 1996 July
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Potential Power of the Pyramidal Structure VIII: Exploration of Periodic Diurnal Oscillation of Pyramid Power and Bio-Entanglement
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作者 Osamu Takagi Masamichi Sakamoto +1 位作者 Kimiko Kawano Mikio Yamamoto 《Natural Science》 CAS 2023年第4期179-189,共11页
To date, numerous books have been published on so-called “pyramid power” but there have been few academic papers on this subject other than our own. Since 2007, to demonstrate the pyramid power, we have undertaken s... To date, numerous books have been published on so-called “pyramid power” but there have been few academic papers on this subject other than our own. Since 2007, to demonstrate the pyramid power, we have undertaken strictly scientific experiments using a pyramidal structure (PS) that we have carefully constructed. In previous reports, we used the edible cucumber, Cucumis sativus as an effective and practical biosensor. Through measurement and analysis of volatile components (gas concentrations) emitted from the biosensor, we were able to demonstrate the existence of the pyramid power and revealed some of its characteristics. In a paper published in 2022, we showed that gas concentration release from this biosensor displayed a circadian rhythm and that this rhythm changed with the season. Based on the result that the biosensor had a periodic diurnal oscillation called a circadian rhythm, we questioned whether or not pyramid power and Bio-Entanglement also had periodic diurnal oscillations. In this paper, we investigated that possibility. Our results have shown that pyramid power and Bio-Entanglement do not exhibit significant periodic diurnal oscillations. Thus we have revealed for the first time that the field associated with pyramid power is a type of static field that always exerts a constant influence. We expect that our research results will be widely accepted in the future and will become the foundation for a new research field in science, with a wide range of applications. 展开更多
关键词 PYRAMID Potential power Bio-Entanglement Diurnal Oscillation Biosensor Cucumis sativus Gas Psi index
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Machine Learning for Hybrid Line Stability Ranking Index in Polynomial Load Modeling under Contingency Conditions
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作者 P.Venkatesh N.Visali 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期1001-1012,共12页
In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression f... In the conventional technique,in the evaluation of the severity index,clustering and loading suffer from more iteration leading to more com-putational delay.Hence this research article identifies,a novel progression for fast predicting the severity of the line and clustering by incorporating machine learning aspects.The polynomial load modelling or ZIP(constant impedances(Z),Constant Current(I)and Constant active power(P))is developed in the IEEE-14 and Indian 118 bus systems considered for analysis of power system security.The process of finding the severity of the line using a Hybrid Line Stability Ranking Index(HLSRI)is used for assisting the concepts of machine learning with J48 algorithm,infers the superior affected lines by adopting the IEEE standards in concern to be compensated in maintaining the power system stability.The simulation is performed in the WEKA environment and deals with the supervisor learning in order based on severity to ensure the safety of power system.The Unified Power Flow Controller(UPFC),facts devices for the purpose of compensating the losses by maintaining the voltage characteristics.The finite element analysis findings are compared with the existing procedures and numerical equations for authentications. 展开更多
关键词 CONTINGENCY hybrid line stability ranking index(HLSRI) machine learning(ML) unified power flow controller(UPFC) ZIP load modelling
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建设金融强国指数报告:分析框架、指标体系与评价结果 被引量:1
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作者 王擎 《金融经济学研究》 CSSCI 北大核心 2024年第5期150-163,共14页
中央金融工作会议提出加快建设金融强国将金融工作上升到党和国家事业发展全局的战略高度,建设金融强国指数编制及数据库建设是核心主题相关研究领域及效应拓展研究领域的基础设施层面的根本需求。遵循习近平总书记关于加快建设金融强... 中央金融工作会议提出加快建设金融强国将金融工作上升到党和国家事业发展全局的战略高度,建设金融强国指数编制及数据库建设是核心主题相关研究领域及效应拓展研究领域的基础设施层面的根本需求。遵循习近平总书记关于加快建设金融强国的系统论述,围绕建设金融强国的关键核心金融要素,在传统的金融发展测评指标的基础上,确立建设金融强国指数编制的七大领域的指标体系;测定和编制全球36个主要经济体的金融发展指数,并从中比较分析中国建设金融强国在全球主要经济体中的实力地位、比较先进性及待提升空间。基于上述研究结论,演绎中国加快建设金融强国的实施路径和发展步骤等多方位措施。本文首次建构建设金融强国的测评指标体系,是为拓展金融发展测评的研究文献的边际贡献。 展开更多
关键词 建设金融强国 金融强国指数 分析框架 跟踪评价 比较先进性
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基于灰色系统理论的电网工程绿色建造模糊综合评价模型
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作者 张琦 姜雪 +2 位作者 张鸥 张爽莹 刘松楠 《沈阳工业大学学报》 CAS 北大核心 2024年第1期42-48,共7页
为贯彻落实绿色发展理念,提升现有电网工程绿色建造评价方法的全面性、系统性以及客观性,提出了一种基于灰色系统理论的模糊综合评价模型。通过研究影响电网工程设计、施工与交付等环节的重要绿色评价因子,构建了多层次的绿色建造评价... 为贯彻落实绿色发展理念,提升现有电网工程绿色建造评价方法的全面性、系统性以及客观性,提出了一种基于灰色系统理论的模糊综合评价模型。通过研究影响电网工程设计、施工与交付等环节的重要绿色评价因子,构建了多层次的绿色建造评价指标体系。并基于灰色系统理论确定指标权重,建立了多层级模糊综合评价模型。同时选取电网工程案例来进行验证,证明了该模型能够科学、合理地确定各指标的权重,从而为电网工程绿色建造评价及不断优化提供了支撑。 展开更多
关键词 电网工程 绿色建造 灰色系统理论 模糊综合评价 评价指标体系 指标权重 多层次 绿色评分
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海上油气平台不稳定电源与储能联合配置优化策略 被引量:1
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作者 胡长斌 刘超 +1 位作者 罗珊娜 冯海波 《中国海上油气》 CAS CSCD 北大核心 2024年第1期143-155,共13页
针对海上油气平台集群接入不稳定电源与储能的联合配置问题,结合海上风电、光伏特点及已有的拓扑结构,提出了三阶段风机/光伏/储能阶段式联合配置策略,介绍嵌入潮流计算的阶段式粒子群算法。第一阶段通过LightGBM网络预测模型得到风机... 针对海上油气平台集群接入不稳定电源与储能的联合配置问题,结合海上风电、光伏特点及已有的拓扑结构,提出了三阶段风机/光伏/储能阶段式联合配置策略,介绍嵌入潮流计算的阶段式粒子群算法。第一阶段通过LightGBM网络预测模型得到风机光伏的时序预测发电功率,再以投资建设经济性和潮流稳定性为目标优化每个节点的风机/光伏容量;第二阶段针对不稳定电源配置后的配电网,提出了基于电压和损耗灵敏度为指标的集群划分方法,将配电网集群划分为若干个子集群;第三阶段根据划分后的子集群,以储能容量、配电网损耗和节点电压波动为目标为每个子集群内配置储能。以渤海油田某10 kV实际油气平台配电网为例,设立燃气机出力功率自定义和经济性自定义两种方案来验证联合配置优化决策的合理性。结果表明,两种配置策略都可以有效地提升海上油气平台配电网的潮流稳定性,提高新能源的渗透率。本文研究验证了海上分散式风机/光伏发电工程的可行性,有利于实现未来海上油气平台的“零碳”建设。 展开更多
关键词 海上油气平台 风电 光伏 储能 优化策略 子集群划分 灵敏度指标 零碳
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黄土高原径流侵蚀功率输沙模型的改进
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作者 于坤霞 李天毅 +4 位作者 贾路 李占斌 李鹏 丛佩娟 李斌斌 《农业工程学报》 EI CAS CSCD 北大核心 2024年第10期107-116,共10页
水土流失对流域生态危害严重,输沙量模拟和预测可以为流域水土流失防治提供依据,因此精确的输沙模型是流域水土流失治理的重要工具。为了精确模拟变化环境下黄土高原年输沙量,该研究基于黄土高原19个水文站的径流和输沙数据,通过随机森... 水土流失对流域生态危害严重,输沙量模拟和预测可以为流域水土流失防治提供依据,因此精确的输沙模型是流域水土流失治理的重要工具。为了精确模拟变化环境下黄土高原年输沙量,该研究基于黄土高原19个水文站的径流和输沙数据,通过随机森林变量重要性度量方法评估年径流侵蚀功率、淤地坝指数、淤地坝相对指数、归一化植被指数、不透水地面积等因子对流域年输沙量的影响,使用非线性最小二乘法估算年输沙模型参数,对比分析不同因子组合的年输沙模型精度,提出适用性较强的黄土高原年输沙模型,据此开展年输沙量变化贡献率分析。结果表明:1)以幂函数形式构建的仅含径流侵蚀功率单因子输沙模型精度与流域面积有显著的负相关关系,相关系数为-0.505(P<0.05),模型精度随着流域面积增大而下降,在面积大于7000 km^(2)的流域适用性较差;2)年径流侵蚀功率、淤地坝指数及不透水地面积因子组合建立的多因子年输沙模型在黄土高原适用性最佳,模型在率定期纳什效率系数平均值为0.84,均方根误差平均值为0.21亿t,在验证期纳什系数平均值为0.79,均方根误差平均值为0.27亿t。3)影响研究流域年输沙量变化的因素依次是:年径流侵蚀功率、不透水地面积和淤地坝指数。研究可以为黄土高原不同区域水土流失防治和生态治理工作提供理论支撑。 展开更多
关键词 侵蚀 径流 年输沙量 径流侵蚀功率 淤地坝指数 不透水地面积 贡献率
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基于功率诊断的微波辅助点火能量沉积研究
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作者 王兆文 许景星 +2 位作者 吴慧珉 刘超辉 成晓北 《内燃机学报》 EI CAS CSCD 北大核心 2024年第3期279-287,共9页
基于功率诊断方法,研究了不同微波参数(脉冲波形和馈入延迟时间)下对微波辅助点火的增强效果,精确测量了点火过程中与火核耦合的微波能量,并分析了能量耦合的内在机制.结果表明:入射的部分微波能量以产生等离子体的形式耦合到点火火核中... 基于功率诊断方法,研究了不同微波参数(脉冲波形和馈入延迟时间)下对微波辅助点火的增强效果,精确测量了点火过程中与火核耦合的微波能量,并分析了能量耦合的内在机制.结果表明:入射的部分微波能量以产生等离子体的形式耦合到点火火核中,耦合能量随微波脉冲功率的增大而提高,随延迟时间的增大而减小,最高耦合能量达到6.16 mJ;火核的增强效果与耦合能量的变化趋势一致,表明耦合的微波能量是点火增强的内在原因;能量耦合效率(耦合能量/入射能量)一般随脉宽和延迟时间增大而减小,最高耦合效率达到7.23%;并发现了微波能量耦合过程中存在从较低的效率转变到较高的稳定耦合效率的现象,将后者定义为饱和耦合模式;脉冲持续时间内到达饱和耦合模式的转变过程越短,能量耦合效率越高;饱和耦合模式下的能量耦合效率不受微波参数的影响,但高功率短脉宽的脉冲波形和低延迟时间能够更快达到饱和耦合模式,明显提高点火增强效果. 展开更多
关键词 微波辅助点火 功率诊断 增强指数 能量沉积 耦合模式转换
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考虑大规模新能源接入的电网性能评价指标体系
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作者 李响 武海潮 +1 位作者 王文雪 安全 《电力系统保护与控制》 EI CSCD 北大核心 2024年第15期178-187,共10页
为了解决传统电网评价体系在评价大规模新能源和电网相互作用复杂机理时存在的不足,建立一套考虑大规模新能源接入的电网性能指标评价体系。首先,从新型电力系统的核心特征出发,贯穿“源网荷储”各个环节,构建包含接入水平、协调水平、... 为了解决传统电网评价体系在评价大规模新能源和电网相互作用复杂机理时存在的不足,建立一套考虑大规模新能源接入的电网性能指标评价体系。首先,从新型电力系统的核心特征出发,贯穿“源网荷储”各个环节,构建包含接入水平、协调水平、适应水平以及承载水平4个维度的电网性能评价指标,显性表达各个指标的统计或计算方式。其次,采用AHP-CRITIC法进行主客观组合赋权,依据电网发展数据自身的客观属性,考虑数据离散程度以及皮尔逊相关系数,挖掘指标间的冲突性和变异性,以增强权重设置的科学性。最后,利用某城市新能源和电网数据对指标体系进行测算,通过对比分析说明所提指标体系与评价方法的有效性,并依据指标灵敏度大小对电网薄弱环节提出发展建议。 展开更多
关键词 新能源 新型电力系统 指标体系 皮尔逊相关系数 权重
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基于改进非线性滑模控制的轮式机器人轨迹跟踪
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作者 杨光永 陈旭东 +1 位作者 徐天奇 蔡艳 《组合机床与自动化加工技术》 北大核心 2024年第9期67-70,75,共5页
针对轮式机器人的轨迹跟踪控制存在的问题,设计了一种改进非线性快速终端滑模控制器(improved nonlinear fast terminal sliding mode controller,INFTSMC)的控制方案。首先,通过对轮式机器人运动学的分析建立了轨迹跟踪误差模型;其次,... 针对轮式机器人的轨迹跟踪控制存在的问题,设计了一种改进非线性快速终端滑模控制器(improved nonlinear fast terminal sliding mode controller,INFTSMC)的控制方案。首先,通过对轮式机器人运动学的分析建立了轨迹跟踪误差模型;其次,在设计滑模控制器阶段,针对非线性快速终端滑模控制器存在奇异点,采用一种新的滑模面幂指数时变策略来设计非奇异终端滑模控制器,解决了非线性快速终端滑模控制器奇异问题,通过构造Lyapunov函数进行稳定性分析证明了该策略的稳定性,并且进行收敛时间分析给出系统从任意初始状态收敛至平衡点所需要的时间;然后,在新的滑模面幂指数时变策略的基础上设计了轮式机器人线速度和角速度控制律,使得轮式机器人轨迹跟踪误差快速收敛至0,实现了移动机器人对期望轨迹的快速跟踪。通过仿真实验与非线性快速终端滑模控制器和传统滑模控制其进行对比,验证了改进非线性快速终端滑模控制器的优越性。 展开更多
关键词 轮式机器人 轨迹跟踪 快速终端滑模控制 时变幂指数 非奇异滑模控制
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钢板桩围堰结构设计及稳定性分析
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作者 袁淑霞 裴龙瑶 +3 位作者 齐文娇 吴松 张宇鹏 段育轩 《科学技术与工程》 北大核心 2024年第8期3155-3163,共9页
钢板桩围堰适用于深水、滩涂等复杂地质,对钢板桩围堰打桩及工作过程进行了稳定性分析。采用Fluent软件对不同工况下打桩过程进行流体动力学研究并计算其动载荷。并对钢板桩稳定性进行了校核。提出流体动力学和固体力学相结合的打桩过... 钢板桩围堰适用于深水、滩涂等复杂地质,对钢板桩围堰打桩及工作过程进行了稳定性分析。采用Fluent软件对不同工况下打桩过程进行流体动力学研究并计算其动载荷。并对钢板桩稳定性进行了校核。提出流体动力学和固体力学相结合的打桩过程稳定性分析方法。采用ANSYS屈曲分析外压载荷作用下围堰整体结构的稳定性。结果表明:动载荷受幂律指数、稠度系数及静载荷的综合影响,稠度系数与流体黏度呈线性关系,幂律指数体现了流体的非牛顿性,而不同载荷作用下流体黏度也会发生变化,需结合屈曲分析结果、打桩时间等综合选择适宜打桩力。采用特征值屈曲分析和非线性屈曲分析得到的围堰临界失稳应力较为接近,非线性屈曲分析考虑了材料的非线性,包含塑性变形成分,因此临界失稳应力更大。 展开更多
关键词 围堰 非牛顿流体 幂律指数 稠度系数 屈曲分析
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