检索结果-南通市图书馆

CSEE Journal of Power and Energy Systems 2024年第3期10卷 1220-1230页

作者： Qiyue Li Yadong Zhu Jinjin ding Weitao Li Wei Sun lijian ding Hefei University of Technology Engineering Technology Research Center of Industrial Automation Hefei 230009China Electric Power Research Institute of State Grid Anhui Electric Power Co. Ltd.Hefei 230000China Hefei University of Technology Hefei 230009China IEEE CSEE

Real-time fault detection is important for operation of smart *** has become a trend of future development to design an anomaly detection system based on deep learning by using the powerful computing power of the ***,delay of Internet transmission is large,which may make the delay time of detection and transmission go beyond the ***,the edge-based scheme may not be able to undertake all data detection tasks due to limited computing resources of edge ***,we propose a cloud-edge collaborative smart grid fault detection system,next to which edge devices are placed,and equipped with a lightweight neural network with different precision for fault *** addition,a sub-optimal and realtime communication and computing resource allocation method is proposed based on deep reinforcement *** method greatly speeds up solution time,which can meet the requirements of data transmission delay,maximize the system throughput,and improve communication *** results show the scheme is superior in transmission delay and improves real-time performance of the smart grid detection system.

关键词： Cloud-edge collaboration communication delay deep reinforcement learning fault detection smart grid

Temperature‐dependent adaptive conductivity coating for surface charge release and electric field control under electro‐thermal coupling field

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2023年第5期8卷 1082-1092页

作者： Jianyi Xue Zhu Zhang Binbin Li Yushun Zhao lijian ding School of Electrical Engineering and Automation Hefei University of TechnologyHefeiChina Electric Power Research Institute of State Grid Anhui Electric Power Co. Ltd.HefeiChina

Surface charge accumulation is the potential criminal for surface insulation failure on spacers under direct current(DC)*** existence of thermal gradient posing the difficulty of surface charge *** study proposes a temperature‐dependent adaptive conductivity coating technique for surppressing surface charge accumulation under electro‐thermal coupling field.A two‐dimensional axis‐symmetrical simulation model regrading surface charge computation is *** effects of thermal gradients and coating conductivity on surface charge and electric field distribution are *** results show that the thermal gradient increases the bulk conductive current,therefore aggravating surface charge *** effects of the coating condcutivity on surface charge and electric field contains three *** lower coating conductivity leads to aggravated homo‐polarity charge *** increasing the coating conductivity,the surface charge and electric field are significantly suppressed at the obtained optimal conductivity,where the bulk and surface conductive current reach a balance *** increasing the coating conductivity results in aggravated hetero‐polarity ***,the increase of thermal gradient to an appropriate extent contributes to the further suppression of surface charge on coated *** is hoped that this study could provide some references for designing highly reliable DC GIL under electro‐thermal coupling field.

关键词： coating charge conductivity

Research on intelligent recognition method for self-blast state of glass insulator based on mixed data augmentation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2023年第4期8卷 668-681页

作者： Siyao Peng lijian ding Weitao Li Wei Sun Qiyue Li Hefei University of Technology HefeiChina

Automatically and accurately detecting the self-blast state of glass insulators is of great significance to operation and maintenance of transmission *** solve the shortcomings of the existing open-loop cognitive models to detect the self-blast state of glass insulators,this study explores a mixed data augmentation-based intelligent recognition method to detect the self-blast state of the glass insulator,by imitating the human cognitive ***,generative adversarial network is utilised to obtain the highquality generative self-blast samples of the glass insulator,and the non-generative data augmentation techniques is used to obtain rich sample ***,considering the characteristics of aerial images such as large scale variations,variable shooting angles and complex backgrounds,feature maps with strong semantics and adaptive multi-scale fusion are extracted using the feature pyramid network with adaptive hierarchy and the multi-deformable convolutional ***,the extracted feature maps are transmitted to a two-dimensional stochastic configuration network that can adaptively generate hidden nodes and basis functions so as to develop the self-blast state classification criteria with universal approximation ***,based on the generalised error and entropy theory,the semantic error entropy evaluation indices of recognition results are defined to evaluate in real time,the credibility of the uncertain recognition results for the self-blast state of the glass ***,based on transfer learning and the established self-optimising feedback mechanism for feature pyramid network,the self-optimising adjustment and reconstruction of the feature map space with strong semantics and multi-scale fusion and its classification criteria are ***,the stacking method is applied to integrate the recognition results of the feature pyramid network with adaptive hierarchy and multi-channel deformable convolutional networks to improve

关键词： insulator network state

Relationship between space charge and nonlinear characteristics of ZnO varistor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第7期54卷 1771-1778页

作者： WANG Qian TU YouPing ding lijian JU ZeLi Beijing Key Laboratory of High Voltage & EMC North China Electric Power University Beijing 102206 China

In order to reveal the conduction mechanism of ZnO varistor, the pulsed electroacoustic (PEA) measurement is employed to investigate the space charge distribution characteristics of ZnO varistors under different current densities in this paper. Experimental results show that the relationship between the space charge and the current density is consistent with the voltage-current characteristics, and can reflect the nonlinear characteristics of ZnO varistor. The space charge increases linearly with the increase of the electric field strength and the current density in the small current region, this reflects the decrease of the surface states of the grain boundary and changes of the Schottky barrier. There exists a transition region between the small current and middle current regions, where the current is composed of the current by the emission of thermally activated electrons and the tunneling current. In the middle current region, the space charge will decrease as the current increases, and will disappear with the depletion layer decreasing to zero.

关键词： ZnO varistors pulsed electroacoustic (PEA) measurement space charge double Schottky barrier

Effect of multiphase content on temperature-dependent electrical conductivity in silicone rubber composites

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

High Voltage 2023年第2期8卷 283-292页

作者： Ying Lin Yuhao Liu Bin Cao Jianyi Xue Liming Wang Jianing Wang lijian ding School of Electrical and Automation Engineering Hefei University of TechnologyHefeiChina Institute of Energy Hefei Comprehensive National Science CenterHefeiChina Laboratory of Advanced Technology of Electrical Engineering and Energy Graduate School at ShenzhenTsinghua UniversityShenzhenGuangdongChina

To investigate how the multiphase structures affect the electrical conductivity in semicrystalline polymer composites,herein,an accurate multiphase content calculation method is proposed and verified,which combines amorphous phase information in broadband dielectric spectroscopy and crystalline phase information in differential scanning *** aluminium hydroxide(ATH)filled silicone rubber as an example,it is found that the rigid amorphous fraction(RAF)corresponding to the chains constrained by crystals(RAF_(cry))is not linearly increased with crystalline fraction(CF).Compared to non-isothermal crystallisation,RAF caused by ATH/silicone rubber interface(RAF_(int))after isothermal crystallisation at 213 K changes little,while mobile amorphous fraction and RAFcry is attenuated and CF is *** on the calculated structures of ATH filled silicone rubber,activation energy of conductivities during cooling is dominated by the thermal transition for conductive ions and shortened distance among the conductive ions through shrunk volumes of the amorphous *** findings deepen the understanding of multiphase content in semi-crystalline polymer composites and its relationship with electrical conductivity,which can be applied in manipulating electrical performance of semi-crystalline polymers by fillers.

关键词： composites rubber electrical

Influence of micro-water on AC breakdown characteristics of C_(4)F_(7)N/CO_(2)gas mixture under non-uniform electric field

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2022年第6期7卷 1059-1068页

作者： Yuan Yang Keli Gao Jiangang Bi lijian ding Shuai Yuan Guangzhen Wang School of Electric Engineering and Automation Hefei University of TechnologyAnhui ProvinceAnhui ProvinceChina State Key Laboratory of Power Grid Environmental Protection China Electric Power Research InstituteBeijingChina

The application of eco-friendly C_(4)F_(7)N/CO_(2)gas mixture has become a hot topic in the power *** obtain the influence law of micro-water on the AC insulation characteristics of C_(4)F_(7)N/CO_(2)gas mixture,breakdown tests were carried out under different non-uniform electric fields and micro-water volume *** the gap distance of 1 mm and the electric field non-uniform coefficient less than 4.42,the breakdown voltage is positively correlated with gas *** the gap distance of 6 mm and the electric field non-uniform coefficient of 9.28,the breakdown voltage shows a typical N-type change trend with the increase of gas *** the gap distance of 9 mm and the electric field non-uniform coefficient up to 16.45,the breakdown voltage shows a typical N-type change trend with the increase of gas ***-water has a negative effect on breakdown voltage under different electric fields,meanwhile the breakdown voltage of slightly non-uniform electric field is greatly affected by micro-water,and the influence of micro-water on breakdown voltage is different under different gas ***,the influence of operating gas pressure and slightly non-uniform electric field should be considered when the micro-water control index of C_(4)F_(7)N/CO_(2)gas mixture insulated equipment is formulated.

关键词： breakdown uniform mixture

Review of the decomposition characteristics of eco-friendly insulation gas

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2021年第5期6卷 733-749页

作者： Yuan Yang Keli Gao lijian ding Jiangang Bi Shuai Yuan Xianglian Yan School of Electrical Engineering and Automation Hefei University of TechnologyAnhui ProvinceChina State Key Laboratory of Power Grid Environmental Protection China Electric Power Research InstituteBeijingChina

As one of the major concerns of climate change,identifying a proper eco‐friendly insulation gas for replacing sulphur hexafluoride(SF_(6))becomes a prominent research topic in recent years.c-C_(4)F_(8),CF_(3)I,C_(5)F_(10O),C_(6)F_(12O)and C4F7N are some potential al-ternatives that are proved to have excellent characteristics,including high insulation strengths and low Global Warming Potentials(GWPs).Beyond these key factors,the decomposition products of these alternatives are closely related to the gases'insulation performance,as well as the safety of operators and the compatibility with other *** addition,the type and content of decomposition products can be used for fault ***,a number of studies were carried out to reveal the decomposition mechanism of these alternative gases,and then to explore the gases'application feasibility and *** recent advances obtained in these studies,including theoretical calcu-lation methods,detection of gas decomposition products,decomposition mechanism are reviewed,and some perspectives for future works are *** is concluded that the phenomenon of solid matter precipitation in c-C_(4)F_(8)and CF_(3)I gas decomposition cannot be ignored and that more research is needed to reveal the influence of buffer gases,micro‐aerobic,micro‐water and other impurities on the gas decomposition process.

关键词： insulation gases characteristics

Quinosumycin,a novel anti-MRSA thioether-linked quinolinone-quinazolinone heterodimer from a marine actinomycete Streptomyces diastaticus NBU2966

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第6期42卷 1991-1997页

作者： Shuangling TAN Yang LIU Haonan FU Yutong XUE Fangjian FENG Jinling LI Xiaojun YAN Sitong WU Shan HE lijian ding Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center Ningbo UniversityNingbo 315211China Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University Taizhou 318053China School of Pharmaceutical Sciences Zhejiang University of TechnologyHangzhou 310014China Ningbo Institute of Marine Medicine Peking UniversityNingbo 315800China

Marine natural products offer a promising source in the development of new antibiotic *** previously undescribed compounds,including one sulfur-bearing alkaloid named quinosumycin(1)along with one chromone derivative namely chromycone(2),were discovered from an ethyl acetate(EtOAc)extract of marine Streptomyces diastaticus NBU2966 through a bioactivity-guided isolation prioritized for antimicrobial *** analysis of nuclear magnetic resonance(NMR)spectroscopy,high resolution electrospray ionization mass spectroscopy(HRESIMS)data,and electronic circular dichroism(ECD)calculations enabled the elucidation of their structures and the determination of their absolute ***(1)is the first heterodimer scaffold incorporating quinolinone and quinazolinone motifs coupled by a thioether ***,Compound 1 exhibited a relatively selective growth inhibition against methicillin-resistant Staphylococcus aureus(MRSA)with the minimal inhibitory concentration(MIC)value of 8μg/mL.

关键词： marine natural product marine Streptomyces thioether alkaloid heterodimer anti-methicillinresistant Staphylococcus aureus(anti-MRSA)

TSC characteristics of AC aged ZnO varistors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2013年第7期58卷 677-682页

作者： TU YouPing WANG Qian HE Jie LI Xiao ding lijian Beijing Key Laboratory of High Voltage & EMC(North China Electric Power University) School of Automation and Information Engineering Xi'an University of Technology China Electric Power Research Institute

The AC aging characteristics and mechanism of ZnO varistors have been widely concerned for a long *** this paper,accelerated aging test of ZnO varistors was carried out based on the "ten degrees and a half" rule,power loss and thermally stimulated current(TSC) of samples were tested during each aging *** test results show that with the increasing of aging time,the power loss increases,the trapped charges increase and the trap level becomes *** addition,the increase of power loss and the increase of trapped charge with the aging time have the same trend.A preliminary analysis shows that the migration of interstitial zinc ions will change the space charge distribution and decrease the Schottky barrier height to cause the change of the trap level.

关键词： ZnO压敏电阻器 TSC AC 中年功率损耗空间电荷分布加速老化老化时间

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

臭氧浓度对HTV硅橡胶材料的老化作用

电工技术学报 2013年第1期28卷 21-28页

作者：屠幼萍王倩李敏丁立健华北电力大学高电压与电磁兼容北京市重点实验室北京102206 华北电力大学新能源电力系统国家重点实验室北京102206

为了研究电晕放电过程中所产生的臭氧对高温硫化(HTV)硅橡胶老化作用的影响,利用研制的臭氧老化试验装置,考虑臭氧浓度及作用时间等因素,对HTV硅橡胶复合绝缘子试样进行了系统的臭氧老化试验,并且对老化后的试样进行了扫描电镜(SEM)、... 详细信息

为了研究电晕放电过程中所产生的臭氧对高温硫化(HTV)硅橡胶老化作用的影响,利用研制的臭氧老化试验装置,考虑臭氧浓度及作用时间等因素,对HTV硅橡胶复合绝缘子试样进行了系统的臭氧老化试验,并且对老化后的试样进行了扫描电镜(SEM)、傅里叶红外光谱(FTIR)分析、憎水性和热刺激电流(TSC)测试。试验结果表明,臭氧能够导致硅橡胶材料表面缺陷增多,憎水性丧失,而且浓度越高,老化会越严重。进一步分析得出,硅橡胶材料在臭氧环境作用下,材料表面平滑、致密的物理结构被破坏,产生了孔洞等缺陷,并且当臭氧环境作用强度达到一定程度后,材料的物理结构的破坏将更为严重;同时,化学基团含量发生变化,试样中Si-O-Si结构减少,羟基和Si-O键增多,试样主链和侧链断裂。

关键词： HTV硅橡胶臭氧浓度老化憎水性热刺激电流(TSC) 微观分析