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Journal of Materials Science & Technology 2021年第15期74卷 1-10页

作者： baoquan wan Haiyu Li Yunhui Xiao Zhongbin Pan Qiwei Zhang Inner Mongolia Key Laboratory of Ferroelectric-related New Energy Materials and Devices Inner Mongolia University of Science and Technology.7#Arding StreetKun DistrictBaotou 014010China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315000ZhejiangChina Key Laboratory of Integrated Exploitation ofBayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China

Conventionally,interface effects between polymers and fillers are essential for determining the breakdown strength and energy storage density of polymer-based dielectric *** this study,we found that interface effects between different fillers have similar *** and Ba TiO3 fiber composite fillers with three different interface bonding strengths were successfully achieved by controlling composite processes(BT-fiber/BN

关键词： Interface effects Breakdown strength Energy storage density Polyimide

Audible Noise Performance of High Voltage AC Conductor Bundles at an Altitude of 226lm

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2447-2455页

作者： wangling He baoquan wan Shilong Huang Yunpeng Liu Jiangong Zhang Xiao Han North China Electric Power University Baoding 071000China China Electric Power Research Institute(State Key Laboratory of Power Grid Environmental Protection) Wuhan 430074China

Extra or ultra-high voltage transmission lines can exhibit strong corona discharge and generate severe audible noise(AN)at high altitudes,which has become a critical limiting factor for power lines ***,the AN data of bundle conductors at high altitudes are very rare,which cannot adequately support the power utilities to make reasonable conductor *** this paper,a sound pressure level(SPL)of 14 types of bundle conductors is investigated by using an ultra-high-voltage(UHV)corona cage(8 m×8 m×35 m)at an altitude of 2216 m,where the bundle numbers between 4 and 12 and the conductor types are used in 500 kV,750 kV or 1000 kV power transmission *** a large number of valuable AN data are obtained;the influences of bundle numbers and sub-conductor diameters on an acoustic power density level(LPWL)are analyzed;and an A-weighted LPWL calculation method is *** addition,by comparing the AN data obtained from the low-altitude area(altitude:23 m),the AN altitude correction factor is concluded,and the influences of conductor parameters and the surface electric field strength on correction factors are *** results obtained in this paper can provide important data for the construction of high-altitude AC power lines.

关键词： AC power lines audible noise corona discharge high altitude

Preparation and Properties of Epoxy Piezoelectric Vibration Reduction Composites

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Journal of Wuhan University of Technology(Materials Science) 2021年第1期36卷 44-49页

作者： TANG Zhong HAO Hua wan baoquan CAO Minghe YAO Zhonghua LIU Hanxing State Key Laboratory of Power Grid Environmental Protection Wuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The epoxy resin (E-51) was used as polymer matrix,conductive carbon black (CB) as conductive filler,and PZT was used to prepare a composite by *** effects of PZT and CB content on the properties of PZT/ CB/ EP piezoelectric composite were *** the PZT content reaches 40 wt%,the optimized vibration attenuation properties of PZT/CB/EP materials could be achieved with a loss factor of 0.9 from room temperature to 60 ℃.With the increase of PZT content,the bending strength of PZT/CB/EP piezoelectric composite vibration reduction material firstly increased from 45 MPa to 65 MPa and then decreased to 38 *** room temperature,the dielectric constant increased from 7 to 50,and the dielectric loss increased from 0.1 to 0.5.

关键词： epoxy resin PZT piezoelectric vibration attenuation composites vibration reduction property

Corona Onset Voltage Gradient of Bundle Conductors for EHV/UHV AC Power Lines in Corona Cages Considering Altitude Correction

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CSEE Journal of Power and Energy Systems 2020年第3期6卷 693-703页

作者： Shilong Huang Yunpeng Liu Shaoshuai Chen Daran Liu wangling He baoquan wan School of Electrical Engineering North China Electric Power UniversityBaoding 071003China School of Electrical Engineering Wuhan UniversityWuhan 430072China China Electric Power Research Institute Beijing 10092China

The corona onset voltage gradient(COG)of conductors is a key parameter in the design of overhead transmission *** commonly used semi-empirical calculation formula proposed by Peek(1910s)at present can roughly estimate the COG of single conductors and is not applicable to large cross-section bundle *** this paper,experiments are conducted to investigate the corona characteristics of a whole series of bundle conductors at different altitudes,and a prediction formula is proposed for the COG of large cross-section bundle conductors on AC transmission lines considering the altitude *** calculated values using the proposed prediction formula are compared with the experimental values of the COG in two cases:UHV eight-bundle conductors at an altitude of 19 m;500 kV UHV four-bundle conductors in Wuhan,Xining,Geermu,and Nachitai at four different *** results show that the use of the formula can predict the COG of bundle conductors with the radius of 1.34 cm to 1.995 cm and the number of subconductors of 4 to 12 at altitudes of 19 m to 4000 m above the mean sea *** research findings can provide a reference for the design of EHV and UHV overhead transmission lines and even those in higher voltage levels.

关键词： Bundle conductor corona onset voltage gradient EHV and UHV transmission lines prediction formula

Statistical Analysis of Radio Interference of 1000 kV UHV AC Double-circuit Transmission Lines in Foul Weather

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CSEE Journal of Power and Energy Systems 2016年第2期2卷 47-55页

作者： Huichun Xie Xiang Cui baoquan wan Jiangong Zhang State Key Laboratory of Alternate Electrical Power System with Renewable Source(NCEPU) Beijing 102206China China Electric Power Research Institute Wuhan 430074China

Analyzing the impact of radio interference(RI)variation during foul weather conditions is an area that has received limited *** paper provides a statistical analysis of RI measurements obtained from a long-term observation station close to the world’s first commercially operating 1000 kV UHV AC double-circuit transmission line in *** six months of observations,the impact of RI was studied on the line during fog,drizzle,and light snow and *** was found that RI increases linearly with the natural logarithm of the precipitation *** Levenberg-Marquardt algorithm(LMA)is employed to fit the RI value with the precipitation *** reasonable distribution of RI in different foul weather is verified by one-sample K-S *** test is seen as beneficial for further RI prediction based on statistical weather mode.

关键词： 1000 kV UHV AC double-circuit transmission line foul weather precipitation intensity radio interference statistical analysis

Dispersion characteristics of switching transients from large‐scale experiments in a 1100 kV gas insulated switchgear circuit

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High Voltage 2023年第6期8卷 1253-1263页

作者： Zihan Teng Weijiang Chen Jiangong Zhang baoquan wan Jun Zhao Kejie Li Zhenghai Liao Zheyuan Gan State Key Laboratory of Power Grid Environmental Protection China Electric Power Research InstituteWuhanChina State Grid Corporation of China BeijingChina School of Electrical Engineering and Automation Hefei University of TechnologyHefeiChina

The switching operation of gas insulated switchgear(GIS)disconnector will produce multiple random spark discharges between the gas gaps of the *** spark discharge can be affected by various random factors,such as trapped charge on the load side,the initial operating phase,gap distance and operating speed of the disconnector,leading to dispersion *** present,some studies have mentioned this dispersion,but its impact is still unclear due to the lack of experimental data,resulting in a deviation between the simulation results and the measured *** this study,thousands of switching operations were carried out based on the 1100 kV full‐scale GIS circuit in Wuhan ultra‐high voltage alternating current Test *** maximal information coeffi-cient analysis,linear regression fitting and other statistical methods were used to discuss the dispersion characteristics of very fast transient overvoltage(VFTO)and transient enclosure voltage(TEV)from large‐scale experimental *** results show that the dispersion of VFTO and TEV in amplitude aspects both increase gradually as the breakdown voltage increases,with the maximum difference of five times of TEV amplitude at normalised breakdown *** terms of frequency characteristics,the dispersion of different fre-quency components in TEV is always greater than that of VFTO,especially for the high‐frequency ***,by comparing the frequency characteristics of TEV at different positions,we notice that the dispersion is almost independent of the spatial po-sition but only determined by the randomness of spark *** discoveries reveal the importance of the dispersion in switching transients and make up for the lack of theoretical understanding of the correlation among them.

关键词： characteristics transient breakdown

Recyclability and Self-Healing of Dynamic Cross-Linked Polyimide with Mechanical/Electrical Damage

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Energy & Environmental Materials 2023年第1期6卷 401-407页

作者： baoquan wan Ming-Sheng Zheng Xing Yang Xiaodi Dong Yuchao Li Yiu-Wing Mai George Chen Jun-Wei Zha School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing 100083China Shunde Graduate School of University of Science and Technology Beijing Foshan 528300China School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059China Centre for Advanced Materials Technology(CAMT) School of AerospaceMechanical and Mechatronic EngineeringThe University of SydneySydney New South Wales 2006Australia Department of Electronics and Computer Science University of SouthamptonSouthampton SO171BJUK

Recyclability and self-healing are two most critical factors in developing sustainable polymers to deal with environmental pollution and resource *** this work,a dynamic cross-linked polyimide insulation film with full closed-loop recyclability is successfully prepared,which also possesses good self-healing ability after being mechanical/electrical damaged depending on the Schiff base dynamic covalent *** recycled and self-healed polyimide film still maintain its good tensile strength(r t)>60 MPa with Young’s modulus(E)>4 GPa,high thermal stability with glass transition temperature(T g)>220℃,and outstanding insulation property with breakdown strength(E 0)>358 kV mm^(-1),making it a very promising low energy consumption and high temperature resistant insulation *** strategy of using Schiff base dynamic covalent bonds for reversible repairing the structure of high T g polyimides promotes the wider application of such sustainable and recyclable material in the field of electrical power and micro-electronics.

关键词： electrical damage polyimide recyclability self-healing

Radio Interference Characteristic of Ultra-high Voltage AC Transmission Lines by Using Stochastic Modeling

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高电压技术 2013年第10期39卷 2438-2444页

作者： HE wangling wan baoquan PEI Chunming ZHANG Jiangong HE Junjia GUO Haozhou School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan 430074 China China Electric Power Research Institute Wuhan 430074 China

For developing ultra-high voltage(UHV) AC power transmission systems,it is important to precisely estimate and to limit the radio interference(RI) level of power *** on the stochastic characteristics in amplitude and repetition rate of induced corona current,by using the probability theory and mathematical statistics,we establish a stochastic model for the wide-sense stationary random process of corona *** combining the stochastic model with model-propagation-analysis method,the RI levels under three-phase UHV AC transmission lines are *** results of the calculation based on stochastic model method and International Council on Large Electric Systems(CIGRE) excitation function are compared with that based on semi-empirical method and some other excitation *** stochastic model based on different excitation functions is also adopted to simulate the RI levels under finite test lines with two opened *** results indicate that with the same average maximum gradient on conductor surface and the same conductor type,the number of corona discharge per unit length is one of the main reasons that causes the difference between different excitation *** is also concluded that for a long test line,the effect of standing wave on RI field strength is negligible in the middle of the line,but obvious near both terminations: for a 10-km line,the maximum difference in RI field strength is 2.78 dB,between the peak value of the standing wave near the ends and the steady value near the middle of the line.

关键词：特高压输电线路交流输电线路无线电干扰随机建模干扰特性概率论与数理统计电力传输系统平稳随机过程

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500kV变电站电磁环境参数测量

高电压技术 2006年第6期32卷 51-55页

作者：孙涛万保权武汉大学电气工程学院

为系统了解高压变电站产生的电磁环境情况，测量了13个500kV高压变电站内、外的工频电、磁场，以及变电站围墙外20m处的无线电干扰水平。测量结果表明，500kV变电站围墙外的工频电、磁场强和无线电干扰水远远低于我国环境标准中推荐的... 详细信息

为系统了解高压变电站产生的电磁环境情况，测量了13个500kV高压变电站内、外的工频电、磁场，以及变电站围墙外20m处的无线电干扰水平。测量结果表明，500kV变电站围墙外的工频电、磁场强和无线电干扰水远远低于我国环境标准中推荐的居民区的场强限值，即电场4kV／m，磁感应强度0．1mT，无线电干扰55dB；500kV变电站内电场强度的最大值为11．66kV／m。但对于所有变电站，70％以上测点的电场强度在4～8kV／m之间。磁感应强度水平分量最大值为13．23μT，垂直分量最大值为9．58μT，最大合成磁感应强度为16．33μT。90％以上测点的合成磁感应强度〈10μT，所测500kV变电站的无线电干扰电平在33～46dB之间。变电站在0．5MHz和1MHz频率下无线电干扰频谱衰减特性不明显。

关键词： 500kV 变电站工频电场工频磁场无线电干扰

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动态可持续聚酰亚胺电介质材料应用与进展

工程科学与技术 2023年第3期55卷 30-39页

作者：万宝全查俊伟北京科技大学化学与生物工程学院北京100083 北京材料基因工程高精尖创新中心北京100083

聚酰亚胺(PI)电介质兼具优异的电气和机械性能以及高热、化学稳定性,被广泛应用于电力、电子设备的生产制造,是绝缘材料的重要组成部分。近年来,随着绿色能源和可持续发展的需求,社会发展更加需要材料在损伤后能够修复、回收等,以实现... 详细信息

聚酰亚胺(PI)电介质兼具优异的电气和机械性能以及高热、化学稳定性,被广泛应用于电力、电子设备的生产制造,是绝缘材料的重要组成部分。近年来,随着绿色能源和可持续发展的需求,社会发展更加需要材料在损伤后能够修复、回收等,以实现再利用。然而,由于PI自身分子结构具有超强的稳定性,分子链在低温条件下难运动,难以实现损伤后的主动修复、回收。因此,必须从本征分子结构角度出发,设计开发适用于PI的新型可逆分子结构来实现材料的动态特性。基于此,本文综述了以PI为基体的回收、修复等动态问题的研究,重点介绍目前动态PI的制备方法、发生动态反应的条件及评估多种损伤形式之间的关系;总结了自修复PI电介质材料,包括共混、共聚及设计制备新型结构单体等工艺手段实现材料的修复特性,以及自修复PI当前的发展现状及面临的困难与挑战;概述了可降解、可回收PI材料的设计制备,通过动态共价键和动态交联网络择优实现PI电介质的回收,对于目前动态PI体系中存在的问题及未来研究方向进行了总结和展望:可以使用新型动态交联剂结合微量有机或无机物料的复合实现PI材料的动态特性和综合性能的协同提升;通过改善工艺或选择动态交联剂实现PI单体和交联剂粉末级别回收,有效避免降解催化剂的影响;需要进一步设计新型功能性单体,从分子结构水平实现可逆以解决PI修复、降解、回收难的问题。

关键词：聚酰亚胺电/机械损伤动态反应可持续发展

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