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Transient AC Overvoltage Suppression Orientated Reactive Power Control of the Wind Turbine in the LCC-HVDC Sending Grid

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 152-161页

作者： Bo Pang Xiao Jin Quanwang Zhang Yi Tang kai liao Jianwei Yang Zhengyou He IEEE College of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China State Grid Zhejiang Electric Power Company HangzhouChina

High-voltage direct current(HVDC) transmission is a crucial way to solve the reverse distribution of clean energy and loads. The line commutated converter-based HVDC(LCCHVDC) has become a vital structure for HVDC due to its high technological maturity and economic advantages. During the DC fault of LCC-HVDC, such as commutation failure, the reactive power regulation of the AC grid always lags the DC control process, causing overvoltage in the AC sending grid, which brings off-grid risk to the wind power generation based on power electronic devices. Nevertheless, considering that wind turbine generators have fast and flexible reactive power control capability, optimizing the reactive power control of wind turbines to participate in the transient overvoltage suppression of the sending grid not only improves the operational safety at the equipment level but also enhances the voltage stability of the system. This paper firstly analyses the impact of wind turbine's reactive power on AC transient overvoltage. Then, it proposes an improved voltage-reactive power control strategy, which contains a reactive power control delay compensation and a power command optimization based on the voltage time series prediction. The delay compensation is used to reduce the contribution of the untimely reactive power of wind turbines on transient overvoltage, and the power command optimization enables wind turbines to have the ability to regulate transient overvoltage, leading to the variation of AC voltage, thus suppressing the transient overvoltage. Finally, the effectiveness and feasibility of the proposed method are verified in a ±800kV/5000MW LCC-HVDC sending grid model based on MATLAB/Simulink.

关键词： Commutation failure LCC-HVDC Transient overvoltage Wind power

Tbx 4 and Tbx 5 gene expression associated with appendage development and its relationship with the absence of the pelvic fin in Pampus argenteus

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Journal of Oceanology and Limnology 2024年第2期42卷 580-593页

作者： Shun ZHANG Xiaojing ZHU Lingzhu HU kai liao Shanliang XU Danli WANG Chunyang GUO School of Marine Science Ningbo UniversityNingbo 315211China Key Laboratory of Applied Marine Biotechnology Ningbo UniversityChinese Ministry of EducationNingbo 315211China

The Tbx family is first known through the study of their functions in the body and limbs,and its members Tbx4 and Tbx5 genes are important factors in determining the characteristics of the *** argenteus is one of the important economical marine fishes widely distributed in offshore ***,it is necessary to study the role of Tbx family genes in the deletion of pelvic fin in *** this study,we cloned Tbx4 and Tbx5 cDNA sequence of ***(GenBank:MH709128 and MH712458).The Western blot and real time PCR were used to detect the expressions of Tbx4 and Tbx5 in different developmental stages and tissues of *** addition,whole-mount in-situ hybridization was used to study the localization of Tbx4 and Tbx5 genes in different developmental stages of *** show that the translation of Tbx4 mRNA was inhibited during the critical period of pelvic fin *** different tissues,Tbx4 protein levels were the lowest in the abdominal epithelium,and even lower than that in the pectoral fin,suggesting that the protein expression was also inhibited in the abdominal epithelium of adult ***,the results indicated that upstream genes regulation led to the key stage-specific and low expression of Tbx4 during pelvic fin development and in the abdominal epithelium.

关键词： Stromateidae pelvic fin protein translation T-box aquaculture broodstock

Review of the Analysis and Suppression for High-frequency Oscillations of the Grid-connected Wind Power Generation System

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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 127-142页

作者： Bo Pang Qi Si Pan Jiang kai liao Xiaojuan Zhu Jianwei Yang Zhengyou He the College of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China IEEE

High-frequency oscillation(HFO)of gridconnected wind power generation systems(WPGS)is one of the most critical issues in recent years that threaten the safe access of WPGS to the *** the WPGS can damp HFO is becoming more and more vital for the development of wind *** HFO phenomenon of wind turbines under different scenarios usually has different ***,engineers need to acquire the working mechanisms of the different HFO damping technologies and select the appropriate one to ensure the effective implementation of oscillation damping in practical *** paper introduces the general assumptions of WPGS when analyzing HFO,systematically summarizes the reasons for the occurrence of HFO in different scenarios,deeply analyses the key points and difficulties of HFO damping under different scenarios,and then compares the technical performances of various types of HFO suppression methods to provide adequate references for engineers in the application of ***,this paper discusses possible future research difficulties in the problem of HFO,as well as the possible future trends in the demand for HFO damping.

关键词： Damping method High-frequency oscillation Stability Wind power generation

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引力透镜时间延迟研究进展

科学通报 2024年第1期69卷 80-95页

作者：廖恺武汉大学物理科学与技术学院武汉430072

引力透镜效应是天文学研究经常用到的重要工具.这个效应中一个有趣的现象是同一天体源在某些情形下能够产生多个像.这些像依次到达地球并被人们观测到.它们之间的到达时间差称为时间延迟,携带着丰富的天文学信息.针对不同的天体源,人们... 详细信息

引力透镜效应是天文学研究经常用到的重要工具.这个效应中一个有趣的现象是同一天体源在某些情形下能够产生多个像.这些像依次到达地球并被人们观测到.它们之间的到达时间差称为时间延迟,携带着丰富的天文学信息.针对不同的天体源,人们发展出特定的观测策略和算法来测量时间延迟.传统的时间延迟观测源为透镜化的类星体.它们的时间延迟是通过对比光变曲线来测量的.在韦布望远镜时代,类星体时间延迟将给出准确的哈勃常数测量值,以期解决当前“哈勃常数争论”.同时,随着时域天文学时代的开启,透镜化的瞬变源,例如各类型的超新星、伽马射线暴及其余辉、快速射电暴和引力波也将被人们大量观测到.对于这些源,时间延迟测量有可能变得更加容易和准确.瞬变源透镜系统将带给我们更多关于引力本性、暗物质性质以及宇宙膨胀的信息.本文基于国内外在时间延迟领域的最新研究进展,介绍了时间延迟的测量方法、测量现状以及它在检验基础物理、研究天体物理和宇宙学方面的应用.

关键词：引力透镜时间延迟类星体瞬变源宇宙学

Discovery and evaluation of a novel 18F-labeled vasopressin 1a receptor PET ligand with peripheral binding specificity

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ACTA PHARMACEUTICA SINICA B 2024年第9期14卷 4014-4027页

作者： Hu, Junqi Li, Yinlong Dong, Chenchen Wei, Huiyi liao, kai Wei, Junjie Zhao, Chunyu Chaudhary, Ahmad Chen, Jiahui Xu, Hao Zhong, Ke Liang, Steven H. Wang, Lu Ye, Weijian Jinan Univ Affiliated Hosp 1 Ctr Cyclotron & PET Radiopharmaceut Dept Nucl Med Guangzhou 510630 Peoples R China Jinan Univ Affiliated Hosp 1 Key Lab Basic & Translat Res Radiopharmaceut Guangzhou 510630 Peoples R China Emory Univ Dept Radiol & Imaging Sci Atlanta GA 30322 USA Sun Yat Sen Univ Sun Yat Sen Mem Hosp Dept Pharm Guangzhou 510120 Peoples R China

The arginine-vasopressin (AVP) hormone plays a pivotal role in regulating various physiological processes, such as hormone secretion, cardiovascular modulation, and social behavior. Recent studies have highlighted the V1a receptor as a promising therapeutic target. In-depth insights into V1a receptor-related pathologies, attained through in vivo imaging and quantification in both peripheral organs and the central nervous system (CNS), could significantly advance the development of effective V1a inhibitors. To address this need, we develop a novel V1a-targeted positron emission tomography (PET) ligand, [F-18]V1A-2303 ([F-18]8), which demonstrates favorable in vitro binding affinity and selectivity for the V1a receptor. Specific tracer binding in peripheral tissues was also confirmed through rigorous cell uptake studies, autoradiography, biodistribution assessments. Furthermore, [F-18]8 was employed in PET imaging and arterial blood sampling studies in healthy rhesus monkeys to assess its brain permeability and specificity, whole-body distribution, and kinetic properties. Our research indicated [F-18]8 as a valuable tool for noninvasively studying V1a receptors in peripheral organs, and as a foundational element for the development of next-generation, brain-penetrant ligands specifically designed for the CNS.

关键词： Vasopressin Autism V1a receptor Positron emission tomography PET imaging Radiolabeling Fluorine 18 Kinetic modeling ARGININE-VASOPRESSIN SOCIAL RECOGNITION SEX-DIFFERENCES AVPR1A GENE AUTISM V1A ASSOCIATION ANTAGONIST OXYTOCIN POTENT

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基于限流电抗器电压的直流配电网单端量保护

高电压技术 2024年第6期50卷 2693-2705,I0018-I0026页

作者：李波廖凯朱禹澜何正友西南交通大学电气工程学院成都611756

直流配电网故障特性复杂,故障电流上升速度快且峰值大,快速、灵敏的故障识别与线路保护是保障直流配电网安全运行的关键技术之一。为此,针对增设限流电抗器的直流配电网,提出一种利用限流电抗器电压实现高灵敏故障识别的直流配电网单端... 详细信息

直流配电网故障特性复杂,故障电流上升速度快且峰值大,快速、灵敏的故障识别与线路保护是保障直流配电网安全运行的关键技术之一。为此,针对增设限流电抗器的直流配电网,提出一种利用限流电抗器电压实现高灵敏故障识别的直流配电网单端量保护方案。首先,通过分析含限流电抗器的直流配电网故障特性,明确区内、区外故障时限流电抗器电压的特征差异。其次,研究限流电抗器对故障特性及直流保护的影响机制,提出虚拟补偿策略以增强故障识别的灵敏性。在此基础上,根据线路电压变化率设计保护启动判据,提出基于虚拟补偿的故障识别判据和故障选极判据,并给出完整的保护方案流程。最后,基于PSCAD/EMTDC仿真平台进行大量的仿真测试,结果表明所提保护方案能够实现对直流故障的快速准确判断,无需通信支持,且对过渡电阻、噪声及负荷波动具有较强的耐受能力。

关键词：直流配电网单端量保护限流电抗器电压故障识别虚拟补偿

喷丸对铝合金亚表面裂纹闭合修复的影响与试验

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表面技术 2024年第7期53卷 180-189页

作者：胡俊廖凯罗鹏博李立君陈飞中南林业科技大学机电工程学院长沙410004

目的研究喷丸修复7075-T651铝合金亚表面裂纹的愈合机理及修复效果。方法建立材料亚表面裂纹在喷丸作用下的修复模型,运用Ansys进行数值模拟计算,并预测裂纹深度修复阈值;根据模型,利用线切割制造相应的裂纹,并对其进行喷丸修复,从残余... 详细信息

目的研究喷丸修复7075-T651铝合金亚表面裂纹的愈合机理及修复效果。方法建立材料亚表面裂纹在喷丸作用下的修复模型,运用Ansys进行数值模拟计算,并预测裂纹深度修复阈值;根据模型,利用线切割制造相应的裂纹,并对其进行喷丸修复,从残余应力、疲劳强度、微观结构等方面分析裂纹愈合的机理,并评估修复效果。结果仿真结果表明,在弹丸直径D=0.5mm、弹丸速度v=100m/s时喷丸修复效果最佳,裂纹修复深度阈值为0.15 mm;裂纹修复区域的表面应力为非裂纹区域的83.17%,实验结果与仿真结果相符;在修复裂纹后,试件的疲劳强度可以达到完好试样的70.32%。剧烈的喷丸冲击使裂纹亚表面材料产生较大的微观形变热,有利于组织形变,促使裂纹两侧的晶粒组织形成闭合挤压,宏观上表现为压应力下组织的紧密闭合,这种闭合起到了修复裂纹的作用,整体上属于物理性修复,但仍无法完全消除裂纹对材料的消极影响。结论喷丸通过压力作用对亚表面材料的裂纹进行闭合修复,使材料的疲劳强度得到恢复,这对于铝合金结构件裂纹的早期修复和应急性修复具有积极作用。

关键词：喷丸 7075-T651铝合金亚表面裂纹裂纹闭合裂纹修复

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大直径单桩基础稳桩平台结构强度分析

船海工程 2024年第3期53卷 107-112,119页

作者：张犇覃廖开江苏龙源振华海洋工程有限公司海上风电工程技术研究院江苏南通226014

针对自升式海上风电安装船/平台自带的抱桩器纠偏载荷较小、传统稳桩平台作业水深有限、均无法满足大直径单桩基础沉桩作业需求等问题,设计一款可适用于大直径单桩基础施工的新型稳桩平台。考虑稳桩平台底部有支撑和无支撑两种情况,采用... 详细信息

针对自升式海上风电安装船/平台自带的抱桩器纠偏载荷较小、传统稳桩平台作业水深有限、均无法满足大直径单桩基础沉桩作业需求等问题,设计一款可适用于大直径单桩基础施工的新型稳桩平台。考虑稳桩平台底部有支撑和无支撑两种情况,采用SESAM软件对其整体结构强度进行计算分析;基于DNV规范,分别采用手工计算校核和ANSYS Workbench软件模拟两种方式,对其主吊耳局部结构强度进行评估。结果表明,新型稳桩平台整体结构强度和主吊耳局部结构强度均满足要求,主吊耳有限元计算应力值较手工校核应力值更大。

关键词：大直径单桩基础稳桩平台结构强度

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页岩油体积压裂后合理焖井时间模拟研究

油气藏评价与开发 2024年第5期14卷 749-755页

作者：廖凯张士诚谢勃勃中国石油大学(北京)克拉玛依校区石油学院中国石油大学(北京)石油工程学院中国石油新疆油田分公司工程技术研究院

针对页岩油藏压裂开发过程中，焖井效果井间差异大、焖井有效性和时效性不明确等问题，建立了考虑裂缝闭合、油水渗吸置换以及压裂液滞留多效应协同的压裂—焖井—生产一体化数值模型，并验证了模型的可靠性，探究了页岩油井压后焖井期... 详细信息

针对页岩油藏压裂开发过程中，焖井效果井间差异大、焖井有效性和时效性不明确等问题，建立了考虑裂缝闭合、油水渗吸置换以及压裂液滞留多效应协同的压裂—焖井—生产一体化数值模型，并验证了模型的可靠性，探究了页岩油井压后焖井期间地层油水运移规律以及合理焖井时间。研究结果表明：(1)焖井期间地层油水运移特征在时间上呈现阶段性变化，依次可分为裂缝闭合、渗吸置换和能量平衡3个主控阶段，同时也在空间上与水力裂缝的复杂程度密切相关；(2)在毛管渗吸作用下，适当延长焖井时间有利于压裂井初期见产，但压裂液在基质中的滞留量增多也会加剧油相相渗伤害，结合累增油量变化规律，明确了合理焖井时间宜在30～45 d；(3)考虑真实工况对焖井作用的影响，提出了以“压裂+焖井时间”作为焖井优化的指标，提高时间效益的同时可以减少井间差异。研究提出了体积压裂水平井焖井作用评价方法和模拟流程，其结果对页岩油压裂后合理焖井时间优化具有指导作用。

关键词：页岩油体积压裂合理焖井时间裂缝闭合渗吸置换数值模拟