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基于模型参数辨识的逆变器故障诊断方法

铁道科学与工程学报 2024年第5期21卷 2119-2130页

作者：罗屿李凯迪陈春阳石英春中南大学交通运输工程学院湖南长沙410075 深圳市地铁集团有限公司广东深圳518000

三相逆变器因已广泛应用于现代工业、交通、航空航天等领域,而具有举足轻重的地位。为解决实际应用中三相逆变器的开路故障严重影响系统正常稳定运行的情形,提出一种基于模型参数辨识的逆变器开路故障的检测和定位方法。该方法通过采集... 详细信息

三相逆变器因已广泛应用于现代工业、交通、航空航天等领域,而具有举足轻重的地位。为解决实际应用中三相逆变器的开路故障严重影响系统正常稳定运行的情形,提出一种基于模型参数辨识的逆变器开路故障的检测和定位方法。该方法通过采集逆变器三相输出电流,将三相电流值进行Clarke变化和归一化处理后,构建逆变器参数模型。将快速递归算法与参数模型结合,对逆变器进行实时参数估计,并将估计的参数组成故障诊断向量,对应逆变器的不同类型的21种开关故障可以形成基准向量矩阵库。正常运行时,监测到的向量和基准模型向量之间的欧氏距离接近于0,而当逆变器发生开路故障时,向量间的欧氏距离将迅速超过一个阈值,据此变化可以检测逆变器是否发生开关开路故障的发生。在检测到开路故障后,对故障开关进行精准定位,通过实时对比与基准模型库向量欧拉距离值得到最小距离所对应的故障标签,通过查询故障分类表,可以定位发生开路故障的开关。在半实物仿真平台开展了逆变器故障的实验,验证方法的有效性和准确性。实验展开了对不同负载下,不同类型的三相逆变器开关管开路故障的诊断,实验结果证明了方法能精确地定位到不同的类型的三相逆变器开路故障,同时也对不同负载运行情况下的故障诊断表现出高鲁棒性。

关键词：逆变器开路故障故障检测故障定位参数辨识

Seasonal and spatial distributions of euphotic zone and longterm variations in water transparency in a clear oligotrophic Lake Fuxian, China

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Journal of Environmental Sciences 2018年第10期30卷 185-197页

作者： Qichao Zhou Yunlin Zhang kaidi li licheng Huang Fengle Yang Yuanyang Zhou Junjun Chang Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed Yunnan Institute of Environmental Science(Kunming China International Research Center for Plateau Lake) School of Ecology and Environmental Science Yunnan University

To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth（Z（eu）） across the four seasons, and no significant correlations between Z（eu） and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Z（eu）in general. Nevertheless, significant differences in Z（eu） between the north region（NR） and the south region（SR） were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter（CDOM） in the NR due to runoff, especially in the rainy seasons（summer and autumn）.CDOM and its terrigenous component had an important impact on Z（eu）in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years,with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants（CDOM and/or phytoplankton） are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.

关键词： Photosynthetic active radiation Diffuse attenuation coefficient Euphotic depth Secchi disk depth Chromophoric dissolved organic matter Yunnan-Guizhou Plateau

Enhancing Image Description Generation through Deep Reinforcement Learning:Fusing Multiple Visual Features and Reward Mechanisms

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Computers, Materials & Continua 2024年第2期78卷 2469-2489页

作者： Yan li Qiyuan Wang kaidi Jia School of Cyber Security Gansu University of Political Science and LawLanzhou730070China

Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually *** study presents an innovative approach employing deep reinforcement learning to enhance the accuracy of natural language descriptions of *** method focuses on refining the reward function in deep reinforcement learning,facilitating the generation of precise descriptions by aligning visual and textual features more *** approach comprises three key ***,it utilizes Residual Network 101(ResNet-101)and Faster Region-based Convolutional Neural Network(Faster R-CNN)to extract average and local image features,respectively,followed by the implementation of a dual attention mechanism for intricate feature ***,the Transformer model is engaged to derive contextual semantic features from textual ***,the generation of descriptive text is executed through a two-layer long short-term memory network(LSTM),directed by the value and reward *** with the image description method that relies on deep learning,the score of Bilingual Evaluation Understudy(BLEU-1)is 0.762,which is 1.6%higher,and the score of BLEU-4 is ***-based Image Description Evaluation(CIDEr)scored 0.998,Recall-Oriented Understudy for Gisting Evaluation(ROUGE)scored 0.552,the latter improved by 0.36%.These results not only attest to the viability of our approach but also highlight its superiority in the realm of image *** research can explore the integration of our method with other artificial intelligence(AI)domains,such as emotional AI,to create more nuanced and context-aware systems.

关键词： Image description deep reinforcement learning attention mechanism

Synthesis of α-tertiary allylsilanes by palladium-catalyzed hydrosilylation of 1,1-disubstituted allenes

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Green Synthesis and Catalysis 2020年第2期1卷 171-174页

作者： kaidi li Ming Nie Wenjun Tang State Key Laboratory of Bio-Organic and Natural Products Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Material Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

We herein report an effective hydrosilylation of 1,1-disubstituted allenes with a palladium catalyst modified by a monophosphorus ligand,leading to a series ofα-tertiary allylsilanes in high yields and exceptional *** employment of BI-DIME is essential for the high reactivities and selectivities.A chiralα-tertiary allylsilane is formed in excellent ee for the first time by employing a chiral monophosphorus ligand.

关键词： α-Tertiary allylsilanes Hydrosilylation of allenes Palladium catalysis Monophosphorus ligands Enantioselectivity

An open-circuit fault-diagnosis method for inverters based on phase current

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Transportation Safety and Environment 2020年第2期2卷 148-160页

作者： Shu Cheng Jundong Zhao Chunyang Chen kaidi li Xun Wu Tianjian Yu Yongsheng Yu School of Traffic and Transportation Engineering Central South University Shenzhen Metro Operation Group Co. Ltd Academy of Science and Technology of Daqin Railway Co. Ltd

The inverter is an indispensable part of a power electronics system. Its safety and stability are important indicators for evaluating the reliability of the system. Inverter faults are usually caused by operating faults in the switch elements. This paper therefore proposes a non-intrusive fault-diagnosis method for open-circuit faults in inverter semiconductor power switches. This method requires only a current signal. It is simple and economical. Faults can be diagnosed quickly using the proposed algorithm. First, the phase current waveforms before and after the open-circuit fault are analysed based on the mathematical model. Then, based on the analysis of the phase currents, the fault features are extracted and the fault is located using the proposed integration algorithm. Finally, the effectiveness and reliability of the proposed fault-diagnosis method are verified using a hardware-in-the-loop experiment.

关键词： fault diagnosis integral algorithm inverter open-circuit fault

A Mitochondria-Targeted PPR Protein Restores pol Cytoplasmic Male Sterility by Reducing orF224 Transcript Levels in Oilseed Rape

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Molecular Plant 2016年第7期9卷 1082-1084页

作者： liu, Zhi Yang, Zonghui Wang, Xiang li, kaidi An, Hong liu, Jie Yang, Guangsheng Fu, Tingdong Yi, Bin Hong, Dengfeng Huazhong Agr Univ Natl Ctr Rapeseed Improvement Wuhan Natl Key Lab Crop Genet Improvement Wuhan 430070 Peoples R China Huazhong Agr Univ Coll Plant Sci & Technol Wuhan 430070 Peoples R China

Cytoplasmic male sterility （CMS） in plants is a maternally inherited inability to produce functional pollen. CMS is generally caused by aberrant mitochondrial genes that are often chimeric in structure and frequentl... 详细信息

关键词： inability mitochondrial transcribed

The Synthesise of MoS2/CuS Materials and Study of Electrochemical Property

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The Synthesise of MoS2/CuS Materials and Study of Electroche...

The microbial community,nutrient supply and crop yields differ along a potassium fertilizer gradient under wheat-maize double-cropping systems

河南省化学会2018年学术年会

作者： li kaidi Du Jimin Ke Jingbo College of Chemistry and Chemical Engineering Anyang Normal University

The MoS was synthesized by solvothermal method using(NH)MoO·4 HO and HNCSNH as raw *** MoS/CuS composites were synthesized by grinding and calcining Cu powder and MoS together.X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),EDS spectrometer,and specific surface and porosity analyzer(BET)were used to characterize the composition,morphology,and specific surface *** electrocatalytic performances of MoS/CuS composites with different mole ratios were studied by linear sweep voltammetry(LSV),Tafel,and electrochemical impedance spectroscopy(EIS).The experimental results show that MoS/CuS-15%composite material has better electrochemical performance.

关键词： Solvothermal method MoS2/CuS Electrocatalytic hydrogen evolution

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Journal of Integrative Agriculture 2024年第10期23卷 3592-3609页

作者： Zeli li Fuli Fang liang Wu Feng Gao Mingyang li Benhang li kaidi Wu Xiaomin Hu Shuo Wang Zhanbo Wei Qi Chen Min Zhang Zhiguang liu Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources andEnvironmentLinyi UniversityLinyi 276000China National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources College of Resources and theEnvironmentShandong Agricultural UniversityTai’an 271018China Key Laboratory of Crop Specific Fertilizer Ministry of Agriculture and Rural Affairs/Xinyangfeng Agricultural Technology Co.Ltd.Jingmen 448001China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110000China

Soil microorganisms play critical roles in ecosystem ***,the relative impact of the potassium(K)fertilizer gradient on the microbial community in wheat-maize double-cropping systems remains *** this long-term field experiment(2008-2019),we researched bacterial and fungal diversity,composition,and community assemblage in the soil along a K fertilizer gradient in the wheat season(K0,no K fertilizer;K1,45 kg ha^(-1) K_(2)O;K_(2),90 kg ha^(-1)K_(2)O;K3,135 kg ha^(-1)K_(2)O)and in the maize season(K0,no K fertilizer;K_(1),150 kg ha^(-1) K_(2)O;K_(2),300 kg ha^(-1)K_(2)O;K_(3),450 kg ha^(-1)K_(2)O)using bacterial 16S rRNA and fungal internally transcribed spacer(ITS)*** observed that environmental variables,such as mean annual soil temperature(MAT)and precipitation,available K,ammonium,nitrate,and organic matter,impacted the soil bacterial and fungal communities,and their impacts varied with fertilizer treatments and crop ***,the relative abundance of bacteria involved in soil nutrient transformation(phylum Actinobacteria and class Alphaproteobacteria)in the wheat season was significantly increased compared to the maize season,and the optimal K fertilizer dosage(K2 treatment)boosted the relative bacterial abundance of soil nutrient transformation(genus Lactobacillus)and soil denitrification(phylum Proteobacteria)bacteria in the wheat *** abundance of the soil bacterial community promoting root growth and nutrient absorption(genus Herbaspirillum)in the maize season was improved compared to the wheat season,and the K2 treatment enhanced the bacterial abundance of soil nutrient transformation(genus MND1)and soil nitrogen cycling(genus Nitrospira)genera in the maize *** results indicated that the bacterial and fungal communities in the double-cropping system exhibited variable sensitivities and assembly mechanisms along a K fertilizer gradient,and microhabitats explained the largest amount of the variation in crop yields,a

关键词： potassium fertilizer gradient microbial community wheat-maize double cropping climate change yield

Upcycling the spent graphite/liCoO_(2) batteries for high-voltage graphite/liCoPO_(4)-co-workable dual-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1745-1751页

作者： Miao Du Hongyan Lü kaidi Du Shuohang Zheng Xiaotong Wang Xiaotong Deng Ronghua Zeng Xinglong Wu Key Laboratory for UV light-Emitting Materials and Technology of Ministry of Education Northeast Normal UniversityChangchun 130024China Faculty of Chemistry Northeast Normal UniversityChangchun 130024China School of Chemistry South China Normal UniversityGuangzhou 510006China

The worldwide proliferation of portable electronics has resulted in a dramatic increase in the number of spent lithium-ion batteries(liBs).However,traditional recycling methods still have limitations because of such huge amounts of spent ***,we proposed an ecofriendly and sustainable double recycling strategy to concurrently reuse the cathode(liCoO_(2))and anode(graphite)materials of spent liBs and recycled liCoPO_(4)/graphite(RLCPG)in li^(+)/PF^(-)_(6) co-de/intercalation dual-ion *** recycle-derived dualion batteries of li/RLCPG show impressive electrochemical performance,with an appropriate discharge capacity of 86.2 mAh·g^(-1) at25 mA·g^(-1) and 69%capacity retention after 400 *** recycling of the cathode and anode from spent liBs avoids wastage of resources and yields cathode materials with excellent performance,thereby offering an ecofriendly and sustainable way to design novel secondary batteries.

关键词： recycle lithium cobalt oxide lithium cobalt phosphate graphite dual-ion batteries spent lithium-ion batteries