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基于改进遗传算法的多源数据继电保护定值优化策略

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电子设计工程 2024年第6期32卷 81-85页

作者：于洋张骏王磊杨瑞金国网安徽省电力有限公司电力调度控制中心安徽合肥230022 国网安徽省电力有限公司超高压分公司安徽合肥230009

针对传统继电保护策略存在准确度差且效率低的问题,文中基于多源数据提出了一种性能更优的继电保护策略。对于多源数据一致性差、分析困难的特点,采用经验模态分解对数据进行预处理,以获得不同梯度的时域以及频域数据。同时为了增强传... 详细信息

针对传统继电保护策略存在准确度差且效率低的问题,文中基于多源数据提出了一种性能更优的继电保护策略。对于多源数据一致性差、分析困难的特点,采用经验模态分解对数据进行预处理,以获得不同梯度的时域以及频域数据。同时为了增强传统遗传算法的分类性能,还引入了极限学习机对输入数据进行分类,并使用遗传算法对极限学习机的参数加以优化。所设计的模型可以对配电网发生的故障进行判定,并引导继电保护设施做出正确响应。实验结果表明,相较于对比算法,该算法具有更高的准确性及更优的效率,且优化后继电保护装置的判断综合准确率可达89%。

关键词：遗传算法经验模态分解极限学习机继电保护多源数据电网优化

维普期刊数据库

数字化变电站继电保护装置故障智能检测识别方法研究

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电子设计工程 2024年第5期32卷 113-117页

作者：于洋王同文汪伟杨瑞金国网安徽省电力有限公司电力调度控制中心安徽合肥230022 国网安徽省电力有限公司超高压分公司安徽合肥230009

为了提升变电站的数字化水平、提高故障的识别精度,文中对继电保护装置故障的智能检测算法进行了研究,并设计了一种基于灰色关联分析的堆栈编码器网络(GRA-SAE)。该网络以自动编码器为基本单元,可实现数据的自动化特征提取。通过支持向... 详细信息

为了提升变电站的数字化水平、提高故障的识别精度,文中对继电保护装置故障的智能检测算法进行了研究,并设计了一种基于灰色关联分析的堆栈编码器网络(GRA-SAE)。该网络以自动编码器为基本单元,可实现数据的自动化特征提取。通过支持向量机(SVM)对提取的特征进行分类识别,并引入灰色关联分析法优化了传统SAE算法中隐藏节点的结构,从而提升了算法的拟合能力。在自建数据集上进行的仿真结果表明,相较于SAE-SVM算法,该算法对异常数据与线路故障的识别精度分别提升了4%和10.27%,证明了GRA-SAE-SVM算法在复杂分类场景下具有更显著的优势。

关键词：堆栈编码器网络支持向量机数字化继电保护故障识别 PSCAD

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Analysis of multi-objective optimisation method for main insulation structure configuration scheme of valve-side winding of ultra-high voltage converter transformer considering multi-field coupling

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High Voltage 2024年第2期9卷 296-308页

作者： Lijun yang Zhidong Cheng Li Cheng ruijin Liao State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqingChina

Because DC conductivities of oil-paper materials can be easily affected by electric field and temperature,the electrical properties under electro-thermal coupling of oil-paper materials should be considered when optimising the insulation structure of valve-side winding of the converter *** on the finite element multi-physical field coupling simulation,the multi-objective optimisation of main insulation structure of valve-side winding is carried *** view of the high time consuming of multi-physical field calculation and the actual needs of an insulation structure optimisation,the Kriging method and technique for order preference by similarity to the ideal solution(TOPSIS)method are introduced,and combines them with NSGA-II to obtain a joint algorithm that can be used for the optimisation of insulation structure of the converter *** using the joint algorithm of multi-objective optimisation,the insulation structure configuration scheme of valve-side winding is *** can be seen from the experiment result that,on the one hand,the joint algorithm adopted can obtain the insulation structure configuration scheme that meets the design *** the other hand,when facing the configuration scheme optimisation under multi-field coupling,the computational time required by this method is only 0.15%of that required by original genetic algorithm.

关键词： converter insulation coupling

Characteristics of LDPE and Oriented Montmorillonite Nanocomposites Produced by Electric Field-inducement

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高电压技术 2013年第8期39卷 1947-1951页

作者： BAI Ge LIAO ruijin yang Lijun YUAN Yuan GU Jia State Key Laboratory of Transmission & Distribution Equipments and Power System Safety and New Technology Chongqing University Chongqing 400030 China

In order to make montmorillonite (MMT) nanosheets disperse in low-density polyethylene (LDPE) with highly homogeneous orientation, alternating voltage is applied to molten LDPE with MMT nanosheets. The effect of electric field on the dispersion of MMT in the solidified LDPE is studied. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses suggest that the MMT nano- sheets are aligned with high anisotropy to the electric field direction, which is perpendicular to the LDPE film plane. Differential scanning calorimetry (DSC) results reveal that the crystallization degree of the oriented LDPE/MMT composite increases. Moreover, through a broadband dielectric spectroscopy analyzer, it is found that MMT manifests a significantly influence in the dielectric property of the oriented composite: the dielectric constant and loss tangent of the composite both become larger. Analysis shows that the electric field-induced torque caused by the polarization of MMT flakes is the main force inducing the orientation of the MMT flakes.

关键词：纳米复合材料 LDPE薄膜电场方向介电特性蒙脱土低密度聚乙烯扫描电子显微镜差示扫描量热法

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Generalized nth-Order Perturbation Method Based on Loop Subdivision Surface Boundary Element Method for Three-Dimensional Broadband Structural Acoustic Uncertainty Analysis

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 2053-2077页

作者： ruijin Huo Qingxiang Pei Xiaohui Yuan Yanming Xu College of Architecture and Civil Engineering Xinyang Normal UniversityXinyang464000China Henan Unsaturated Soil and Special Soil Engineering Technology Research Center Xinyang Normal UniversityXinyang464000China Henan International Joint Laboratory of Structural Mechanics and Computational Simulation College of Architecture and Civil EngineeringHuanghuai UniversityZhumadian463000China

In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering *** Burton-Miller method is employed to solve the problem of non-unique solutions that may be encountered in the external acoustic field,and the nth-order discretization formulation of the boundary integral equation is *** addition,the computation of loop subdivision surfaces and the subdivision rules are *** order to confirm the effectiveness of the algorithm,the computed results are contrasted and analyzed with the results under Monte Carlo simulations(MCs)through several numerical examples.

关键词： Perturbation method loop subdivision surface isogeometric boundary element method uncertainty analysis

Sensitivity Analysis of Electromagnetic Scattering from Dielectric Targets with Polynomial Chaos Expansion and Method of Moments

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 2079-2102页

作者： Yujing Ma Zhongwang Wang Jieyuan Zhang ruijin Huo Xiaohui Yuan College of Architecture and Civil Engineering Xinyang Normal UniversityXinyang464000China Henan International Joint Laboratory of Structural Mechanics and Computational Simulation College of Architecture and Civil EngineeringHuanghuai UniversityZhumadian463000China Academy of Military Sciences Beijing100091China Henan New Environmentally-Friendly Civil Engineering Materials Engineering Research Center Xinyang Normal UniversityXinyang464000China

In this paper,an adaptive polynomial chaos expansion method(PCE)based on the method of moments(MoM)is proposed to construct surrogate models for electromagnetic scattering and further sensitivity *** MoM is applied to accurately solve the electric field integral equation(EFIE)of electromagnetic scattering from homogeneous dielectric *** the bistatic radar cross section(RCS)as the research object,the adaptive PCE algorithm is devoted to selecting the appropriate order to construct the multivariate surrogate *** corresponding sensitivity results are given by the further derivative operation,which is compared with those of the finite difference method(FDM).Several examples are provided to demonstrate the effectiveness of the proposed algorithm for sensitivity analysis of electromagnetic scattering from homogeneous dielectric targets.

关键词： Adaptive polynomial chaos expansion method method of moments radar cross section electromagnetic scattering

P2P Energy Trading Considering Prosumer Preference and System Risk

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1179-1194页

作者： Xinyu He Ping Dong Mingbo Liu Xuewei Huang Wenli Deng ruijin He School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China IEEE

As an important means of mobilizing demand-side resources,peer-to-peer(P2P)energy trading has drawn more and more attention from *** paper constructs a P2P energy trading framework considering prosumers’trading partner preferences(TPPs)and system *** first,we build the P2P trading models of prosumers equipped with different distributed energy resources(DERs),and TPP ***,to solve the established energy trading problem,a fully distributed double-consensus alternating direction method of multipliers(DC-ADMM)is proposed,which can achieve transaction consensus when considering market players’***,a risk-based security constrained economic dispatch(RBSCED)model based on AC power flow is established for the first time,by which a distribution system operator(DSO)checks system security and obtains risk-based locational marginal prices(RLMPs).Moreover,double-regulated price signals related to RLMPs which contain grid utilization prices(GUPs)and DSO’s retail prices realize management of players’*** the end,the proposed method is applied to an IEEE33 bus distribution *** show the proposed method effectively reduces system risk and ensures secure operation of system without direct management.

关键词： Double-consensus ADMM grid utilization price price signal risk-based locational marginal price trading partner preference

Radio frequency heating to inactivate microorganisms in broccoli powder

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Food Quality and Safety 2017年第1期1卷 93-100页

作者： Yicun Zhao Wei Zhao ruijin yang Jaideep Singh Sidhu Fanbin Kong State Key Laboratory of Food Science and Technology School of Food Science and Technology Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxiChina Department of Food Science&Technology University of GeorgiaAthensGeorgiaUSA

Recently,the safety of low-water-activity(aw)foods,including dried vegetables,has become a major *** has been realized that microorganisms may not grow in low-aw foods but can survive for rather long period of *** it represents significant risk especially when the lowaw foods are added to high-aw foods,because the inhibited microorganisms in low-aw foods will grow in high-aw *** this study,broccoli powder(aw=0.586)was pasteurized by radio frequency(RF)treatment using a 6 kW,27.12 MHz pilot-scale RF *** patterns and temperature profiles in broccoli powder package in a polypropylene plastic pouch(17×12×5 cm)during RF heating were *** non-uniform heating pattern was validated,characterized by much higher temperatures(about 17–32°C)in the interior and centre of the food powder package than that in the exterior *** over and rotation during RF treatment were proven effective to improve the heating *** reduction and change of colour of broccoli powder after RF heating for different time periods were studied,and the results showed that the level of microbial inactivation was greatly reduced by 4.2 log colony-forming units(CFU)/g with insignificant colour degradation after RF heating for 5 *** study also indicated that cold-shock treatment[kept the treated sample at freezing temperature(−18°C)for 48 h]following RF treatment further effectively reduced the microorganisms in broccoli powder from 3.0 log CFU/g immediately after RF treatment to less than 30 CFU/g,which indicated that cold shock in conjunction with RF heating is a promising technology with a potential to reduce the strength of applied RF and thus contributing to better retention of quality of low-moisture foods.

关键词： Low-water-activity foods broccoli powder radio frequency(RF) decontamination

Geometric and defects engineering collaboration for enhanced cascade enzymatic nanoreactors

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Nano Research 2024年第4期17卷 2451-2461页

作者： Zhichao Yu ruijin Zeng Hexiang Gong Yuan Gao Shuyun Chen Yunsen Wang Dianping Tang Key Laboratory for Analytical Science of Food Safety and Biology(MOE&Fujian Province) Department of ChemistryFuzhou UniversityFuzhou 350108China

Highly evolved multi-enzyme cascade catalytic reactions in organisms facilitate rapid transfer of substrates and efficient conversion of intermediates in the catalytic unit,thus rationalizing their efficient *** this study,pore-ordered mesoporous single-atom(Fe)nitrogen-doped carbon nanoreactors(Mp-Fe-CN)were designed,in which a reasonable pore size was designed as a natural enzyme trap coupled to a simulated enzyme center.A polarity-mediated strategy was developed to obtain atomically dispersed nanoporous substrates,with the finding that polarity-guided engineering of the nitrogen-ligand environment and vacancy cluster defects clearly affects nanoporous activity,accompanied by appreciable mesoporous pore size *** active center and distal N atom coordination of Fe-N_(4) affect the catalytic process of the nanozyme exposed by density functional theory(DFT),determining the contribution of hybridized orbitals to electron transfer and the decisive step.A cascade nanoreactor-based domain-limited sarcosine oxidase developed for non-invasive monitoring of sarcosine levels in urine for evaluation of potential prostate carcinogenesis as a proof of *** on the design of surface mesoporous channels of nanocatalytic units,a bridge was built for the interaction between nanozymes and natural enzymes to achieve cascade nanocatalysis of natural enzymatic products.

关键词： nanozyme single-atom catalyst bioreactor cascade catalysis non-Invasive sensing