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打印微结构对表面电荷积聚特性的影响

高电压技术 2024年第5期50卷 2237-2246页

作者：姚亦桐杨洋牛广乾钱志源刘承山穆海宝西安交通大学电工材料电气绝缘全国重点实验室西安710049 上海宇航系统工程研究所上海201109

航天器等真空设备面临着高电压、小型化的发展需求,但其中的固体-真空绝缘界面容易发生真空沿面闪络。为了提升真空绝缘的沿面耐电性能,通过3D打印技术在绝缘介质表面构建了微刻槽和打印金属两种微结构,并通过电荷积聚实验研究发现了打... 详细信息

航天器等真空设备面临着高电压、小型化的发展需求,但其中的固体-真空绝缘界面容易发生真空沿面闪络。为了提升真空绝缘的沿面耐电性能,通过3D打印技术在绝缘介质表面构建了微刻槽和打印金属两种微结构,并通过电荷积聚实验研究发现了打印微结构能有效抑制表面电荷积聚过程;同时,改变微刻槽数量以及金属的宽度和数量,进一步通过实验对比研究了参数不同时的情况,发现增加微结构的数量和宽度均有利于提升其对电荷积聚的抑制效果;最后,构建真空沿面闪络粒子仿真模型,通过研究电子运动和二次电子崩的发展,并结合实验结果发现微结构能够散射电子,从而产生抑制电荷积聚、提升沿面耐电强度的效果。

关键词：真空沿面闪络 3D打印打印微结构电荷积聚二次电子崩耐电强度

Review of surface transient charge measurement on solid insulating materials via the Pockels technique

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High Voltage 2021年第4期6卷 608-624页

作者： Bo Zhang Jianyi Xue Xingyu Chen Sile Chen haibao mu Yang Xu Guanjun Zhang State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi'an Jiaotong UniversityXi'anShaanxiPeople's Republic of China

Surface charges accumulated on solid insulating materials in electrical apparatuses and electronic devices could distort the initial electric field and severely damage the insulation *** transient surface charge measurement is critical to determine the mechanisms of charge transport and flashover occurrence,and estimate surface insulation strength under high *** measurement technique based on the Pockels electro-optic effect is considered as the only approach for 2-D dynamic charge distribution behaviour so far,and it has good capability to avoid original electric field distortion caused by conven-tional methods featured by metal *** paper reviews recent progress of the non-invasive dynamic surface charge measurement systems on the Pockels *** focus especially on typical systems with transmitting and reflecting configurations and the frequently used fast inversion *** can be inferred that higher spatial-temporal resolution,higher signal-to-noise ratio,and better compatibility for both transparent and opaque materials are the future development trends,which greatly depend on multiple technological breakthroughs at impact-resistant electro-optic crystals,advanced high-speed photography and high-performance inversion *** addition,the recent studies on transient behaviour of surface discharge,together with the present limitation and future prospects are *** is expected that more ideas will be inspired in transient surface charge measurement by the Pockels technique and other relevant electro-optic methods.

关键词： transient charge surface

Space Charge Characteristics of Oil-paper Insulation with New Paper and Aged Oil

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高电压技术 2013年第8期39卷 1865-1872页

作者： mu haibao WANG Da WANG Shiqiang TIAN Jie LI Yuan WEI Yanhui ZHANG Guanjun State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical Engineering Xi'an Jiaotong University Xi'an 710049 China Measurement Center of Guangzhou Power Supply Bureau Co. Ltd Guangzhou 510730China SINOPEC Safety Engineering Institute Qingdao 266071 China Shenzhen Power Supply Co. Ltd. Shenzhen 518000 China

Oil-paper compound insulation has been widely used in power transformers for quite a long time because of its good performances. The insulation gradually degrades under combined thermal, electrical and chemical stresses during routine operations, mainly because of space charges inside. This work investigated the space charge characteristics in oil-paper insulation under oil aging circumstance. New trans- former oil samples are thermally aged to obtain different aging states, and their physical and chemical properties are analyzed. New Kraft papers are dried in vacuum and fully immersed in these different aged oil samples, and three kinds of oil-paper samples are obtained. We use the pulsed electro-acoustic (PEA) method to measure space charge under both DC voltage-on and voltage-off conditions at room temperature. The effect of oil aging state on characteristics of space charge injection, accumulation, and decay is analyzed and discussed. The results show that comparing with the DC voltage-off condition, more charges are injected into samples at the interface of electrode and dielectric when DC voltage is on. When the oil-aged state gets worse, more charges are induced at both cathode and anode, more space charges are accumulated in the bulk, the area of negative charges is larger, and local electric field is distorted more seriously. Moreover, for the voltage-off condition, aged oil is good for space charge decay, and trapped positive space charges decay faster than trapped negative charges.

关键词：空间电荷油纸绝缘电荷特性老年老化状态直流电压衰减特性电荷积累

A tree-growing graphic model for asymmetrical phantom networks in polymeric gels undergoing dynamic mechanochemical coupling

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Science China(Technological Sciences) 2024年第2期67卷 558-567页

作者： SHI WeiLin ZHOU Jian LU haibao ELMARAKBI Ahmed FU Yong-Qing National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Faculty of Engineering and Environment University of NorthumbriaNewcastle upon Tyne NEI 8STUK

Network structures of various polymers have significant effects on their mechanical properties;therefore,numerous studies have investigated the constitutive relationship between symmetrical network structures and their rubber elasticity in ***,few studies have focused on asymmetrical network structures in polymers that undergo bond exchange reactions,selfassembly,or mechanochemical coupling—all of which are induced by transition probabilities of chemical bonding *** this study,an extended constraint junction and phantom network model is formulated using the tree-growing theory to establish a constitutive relationship between asymmetrical network structures and their rubber elasticity in polymers.A free-energy equation is further developed to explore working principles of configurational transitions on the dynamic rubber elasticity of symmetrical and asymmetrical network *** constitutive relationship between dynamic rubber elasticity and symmetrical and asymmetrical network structures has also been proposed for the gels undergoing mechanochemical and hydromechanical ***,the effectiveness of this newly proposed tree-growing model has been verified by comparing with the classical affine network model,finite element analysis,and the experimental results of gels reported in literature.

关键词： gel polymer network rubber elasticity asymmetric

Pockels效应表面电荷测量中电荷反演算法的研究

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中国电机工程学报 2011年第13期31卷 135-141页

作者：穆海宝张冠军郑楠田中康宽电力设备电气绝缘国家重点实验室(西安交通大学) 陕西省西安市710049 日本东京都市大学测量与电机控制实验室

Pockels效应表面电荷测量技术以其特有的技术优势逐步用于表面放电和等离子体的研究,然而如何准确获取表面电荷分布仍然是一个重要的研究课题。对Pockels效应表面电荷测量技术中的表面电荷反演算法进行研究,采用二维傅里叶变换将测量信... 详细信息

Pockels效应表面电荷测量技术以其特有的技术优势逐步用于表面放电和等离子体的研究,然而如何准确获取表面电荷分布仍然是一个重要的研究课题。对Pockels效应表面电荷测量技术中的表面电荷反演算法进行研究,采用二维傅里叶变换将测量信号和表面电荷的复杂关系转换到频域中进行计算,并采用维纳滤波算法进行信号处理。计算结果和传统算法的计算结果进行了对比,结果表明,改进算法在数值计算过程中考虑材料厚度、介电特性及不同位置电荷影响等因素,计算方法更为合理。该方法可用于不同材料表面电荷的测量计算。另外,算法中维纳滤波器是计算算法中关键的组成部分,对降低系统噪声,提高数值计算的稳定性能够起到很重要的作用。

关键词： Pockels效应表面电荷测量二维傅里叶变换维纳滤波

纳秒脉冲下CO_(2)/He气体均匀放电特性

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高电压技术 2021年第4期47卷 1495-1503页

作者：张恬波穆海宝郭毅豪张冠军西安交通大学电气工程学院电力设备电气绝缘国家重点实验室西安710049

低温等离子体在CO_(2)催化转化方面具有广阔的应用前景,成为国内外的研究热点。常用的电弧、微波或介质阻挡放电应用于CO_(2)转化时通常处于电弧或丝状放电状态,难以调控其电学参数,限制了转化机理的深入研究。为此,提出一种纳秒脉冲激... 详细信息

低温等离子体在CO_(2)催化转化方面具有广阔的应用前景,成为国内外的研究热点。常用的电弧、微波或介质阻挡放电应用于CO_(2)转化时通常处于电弧或丝状放电状态,难以调控其电学参数,限制了转化机理的深入研究。为此,提出一种纳秒脉冲激励的获得板-板裸电极下CO_(2)/He可调均匀放电的方法,通过对电学参数的测量,发现CO_(2)体积分数越高,脉冲重复频率(pulse repetition frequency,PRF)越低,稳定放电电压就越高。利用放电图像和光谱探究了不同放电条件对放电稳定性的影响机制,结果显示稳定放电具有辉光放电的特征,后续伴随类汤森放电的余辉。进一步利用特征谱线强度比值r(O_(2)/He)以及CO(B1∑→A1∏)谱带相对强度,分别分析验证了CO_(2)体积分数对放电的影响途径,以及CO_(2)/He在重复频率纳秒脉冲下放电的记忆效应。

关键词： CO_(2)/He放电纳秒脉冲发射光谱脉冲重复频率均匀放电

油老化状态对油纸绝缘直流电场下空间电荷特性的影响

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中国电机工程学报 2013年第22期33卷 175-182,26页

作者：王妲王世强田杰穆海宝张冠军电力设备电气绝缘国家重点实验室(西安交通大学) 陕西省西安市710049 深圳供电局有限公司广东省深圳市518000

为了深入研究油老化对油纸绝缘直流电场下空间电荷特性的影响,通过加速热老化得到三组不同老化程度的绝缘油试样,并对其进行理化及电气特性分析;然后利用所得油样分别对经过真空干燥的新绝缘纸进行真空浸渍,得到3组油老化状态不同的油... 详细信息

为了深入研究油老化对油纸绝缘直流电场下空间电荷特性的影响,通过加速热老化得到三组不同老化程度的绝缘油试样,并对其进行理化及电气特性分析;然后利用所得油样分别对经过真空干燥的新绝缘纸进行真空浸渍,得到3组油老化状态不同的油纸绝缘试品;进而采用电声脉冲法(pulsed electro-acoustic,PEA)在室温下分别测量了3组试品在施加直流电压和撤除电压情况下的空间电荷分布,讨论了油老化状态对油纸绝缘试品中空间电荷注入、积聚及消散等特性的影响。实验结果表明:施加直流电压下,3组油浸纸试品与电极界面处均发生了同极性电荷注入现象,油老化程度越严重,电极与介质界面处感应的电荷密度峰值越大,积聚在试品中的空间电荷总量也逐渐增大,负电荷积聚区域逐渐向阳极方向推进。撤除电压后,随着绝缘油老化程度的加重,试品中的空间电荷消散速率增大,且正电荷的消散速率大于负电荷的消散速率。

关键词：油纸绝缘油老化电声脉冲法空间电荷

Azobenzene-based ultrathin peptoid nanoribbons for the potential on highly efficient artificial light-harvesting

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Science China Chemistry 2024年第5期67卷 1680-1686页

作者： Zichao Sun Lingrong Zhu Jingze Liu Fan Liu Pengchao Wu Pengliang Sui haibao Jin Shaoliang Lin Shanghai Key Laboratory of Advance Polymeric Materials Frontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The development of artificial light-harvesting systems based on long-range ordered ultrathin organic nanomaterials(i.e., below3 nm), which were assembled from stimuli-responsive sequence-controlled biomimetic polymers, remains challenging. Herein,we report the self-assembly of azobenzene-containing amphiphilic ternary alternating peptoids to construct photo-responsive ultrathin peptoids nanoribbons(UTPNRs) with a thickness of ~2.3 nm and the length in several micrometers. The pendants hydrophobic conjugate stacking mechanism explained the formation of one-dimensional ultrathin nanostructures, whose thickness was highly dependent on the length of side groups. The photo-isomerization of azobenzene moiety endowed the aggregates with a reversible morphology transformation from UTPNRs to spherical micelles(46.5 nm), upon the alternative irradiation with ultraviolet and visible light. Donor of 4-(2-hydroxyethylamino)-7-nitro-2,1,3-benzoxadiazole(NBD) and acceptor of rhodamine B(RB) were introduced onto the hydrophobic and hydrophilic regions, respectively, to generate photocontrollable artificial light-harvesting systems. Compared with the spheres-based systems, the obtained NBD-UTPNRs@RB composite proved a higher energy transfer efficiency(90.6%) and a lower requirement of RB acceptors in water. A proof-ofconcept use as fluorescent writable ink demonstrated the potential of UTPNRs on information encryption.

关键词： azobenzene-based peptoid ultrathin nanoribbon photo-responsive light-harvesting information encryption

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大型电力变压器损耗带电测试技术研究

电工技术学报 2019年第4期34卷 683-692页

作者：张荣伦王帅穆海宝张冠军黄松海南电网有限责任公司电力科学研究院海口570100 西安交通大学电力设备电气绝缘国家重点实验室西安710049

电力变压器的损耗特性可以反映其运行状态,关系到电力系统的安全稳定。传统变压器损耗测试需进行离线试验,影响供电连续性且不能反映真实情况。本文提出电网系统供电的变压器空载及负载损耗带电测试新方法,并采用加窗插值算法处理数据... 详细信息

电力变压器的损耗特性可以反映其运行状态,关系到电力系统的安全稳定。传统变压器损耗测试需进行离线试验,影响供电连续性且不能反映真实情况。本文提出电网系统供电的变压器空载及负载损耗带电测试新方法,并采用加窗插值算法处理数据以减小频谱泄漏和栅栏效应的影响。基于测量方法,开发变压器损耗带电测试系统,包括空载损耗测量和负载损耗测量两部分,以解决空载电流测量精度、电压电流采集同步性及复杂现场的干扰等问题。对现场变压器损耗进行测试,取得了较好结果,验证了系统带电测试变压器损耗的可行性。

关键词：电力变压器损耗特性带电测试加窗插值算法