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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

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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

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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

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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

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

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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

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基于响应面法的变压器绕组电磁力高效计算

中国电机工程学报 2024年第16期44卷 6685-6696,I0033页

作者：陈志伟何云翔黄胜鑫向念文齐冬莲吴杰丁立健合肥工业大学电气与自动化工程学院安徽省合肥市230009 浙江大学电气工程学院浙江省杭州市310027 国网安徽省电力有限公司电力科学研究院安徽省合肥市230601

为解决传统有限元法求解绕组电磁力速度慢、模型参数固定等问题,该文提出将响应面拟合计算的方法运用在变压器绕组电磁力的计算上,实现在不同工况的绕组电流下的变压器绕组电磁力的快速计算分析,且能考虑到绕组辐向形变对其所受电磁力... 详细信息

为解决传统有限元法求解绕组电磁力速度慢、模型参数固定等问题,该文提出将响应面拟合计算的方法运用在变压器绕组电磁力的计算上,实现在不同工况的绕组电流下的变压器绕组电磁力的快速计算分析,且能考虑到绕组辐向形变对其所受电磁力的影响。首先,采用有限元软件对一台三相变压器进行参数化建模和“场-路”耦合仿真,由此得出该变压器绕组的电流、漏磁、电磁力分布规律;其次,通过设计的电磁力测量实验设计,比较仿真计算与实验测算的漏磁和电磁力分布,验证该文所建立模型的可靠性。最后,结合试验设计(design of experiments,DOE)和拉丁超立方采样开展绕组电磁力响应面设计,构建绕组辐向、轴向电磁力与特定规律下的绕组形变和绕组电流的拟合关系,并验证响应面计算的精度。该方法能为电力变压器绕组抗冲击能力的提升及电力设备数字化分析提供技术参考。

关键词：变压器绕组电磁力响应面法快速计算数字孪生

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大功率高能脉冲激光电源设计

强激光与粒子束 2024年第5期36卷 56-61页

作者：李贺龙徐健杨之青宋家豪吴周宇汤义辉赵爽丁立健电能高效高质转化全国重点实验室(合肥工业大学) 合肥230009 合肥综合性国家科学中心能源研究院(安徽省能源实验室) 合肥230031

根据YAG激光器对大功率高能量脉冲电源的应用需求,设计了一种大功率脉冲激光电源,可实现高脉冲能量重复频率输出及充电电压灵活调控。前级充电网络采用串联LC谐振变换器,后级脉冲形成网络选择晶闸管触发LC放电电路。最终,研制了1台7 kW... 详细信息

根据YAG激光器对大功率高能量脉冲电源的应用需求,设计了一种大功率脉冲激光电源,可实现高脉冲能量重复频率输出及充电电压灵活调控。前级充电网络采用串联LC谐振变换器,后级脉冲形成网络选择晶闸管触发LC放电电路。最终,研制了1台7 kW实验样机,最大重复频率10 Hz,最高充电电压2.2 kV,可实现单脉冲最高700 J电能输出,满足大功率高能脉冲输出的应用需求,实验测试结果验证了设计的可行性。

关键词： YAG激光器串联LC谐振变换器脉冲激光电源高脉冲能量输出

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

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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

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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

Unveiling the time-temperature dependence of metastability of supercooled liquid using nano-calorimetry

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 119-127页

作者： Yijun ding lijian Song Zheng Wang Ruiqi Yu Junqiang Wang Lina Hu Yuanzheng Yue Edgar D.Zanotto Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong University Jinan 250061China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Experimental Teratology Shandong University Jinan 250061 China Department of Chemistry and Bioscience Aalborg UniversityAalborg 9220Denmark Department of Materials Engineering Federal University of Sao CarlosSao Carlos SP 13.565-905Brazil

There is a lack of understanding of both the conversion of an unstable glass into a metastable supercooled liquid(MSL) upon heating and the metastability of MSLs. In this study, we investigated the time-and temperature-dependent metastability of an MSL using an advanced nano-calorimetric technique. The chosen Au-based metallic glass(Au MG) allowed adequate probing of its MSL in a temperature range between 10 and 70 K above the standard glass transition temperature. We found that the survival time of the MSL state is a quadratic function of temperature. Beyond this duration threshold, the sample undergoes fast crystallization even if it is below the crystallization temperature that is measured using differential scanning *** transmission electron microscopy, we observed the formation of clusters with a partially ordered lattice structure during relaxation in the Au MG sample fabricated using a nano-calorimeter. The atomic ordering within the clusters was enhanced by increasing time and temperature in the MSL region. Once the as-produced glass entered the MSL stage upon heating followed by a quenching stage at a given rate, the mechanical properties of the quenched glass remained the same regardless of its holding temperature and duration within the MSL region. This work provides insights into the glass-MSL-crystal transformation and offers guidance for designing standard metallic glasses for property characterizations.

关键词： metallic glass supercooled liquid relaxation nucleation nano calorimetric technology

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