Results 31 to 40 of about 81,440 (198)
±800 kV直流输电是目前世界上直流输电领域电压等级最高的输电方式。±800 kV特高压直流换流阀是特高压直流输电(UHVDC)中的关键设备,在投入电网使用之前必须要进行严格的型式试验。单阀交流耐压试验,是特高压直流换流阀绝缘型式试验中一个比较特殊的试验项目。笔者以国内自主试验的首例±800 kV换流阀绝缘型式试验为例,介绍了±800 kV换流阀相关电气结构,并对单阀交流试验的加压方法进行了研究。
李强 +6 more
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Noise Characteristics of ±800 kV HVDC Convert StationBased on Spectrum Analysis
By collecting the sound pressure signals of the aerodynamic noise of the converter transformer fans, the electric field noise of the smoothing reactors and the electric field noise of the DC/ AC filter field in the 800 kV converter station, the spectrum ...
Yu HAN, Chao FAN, Guangke WANG, Qiang HE
doaj +1 more source
Creep Properties and Deformation Mechanism of Additively Manufactured NiAl‐CrMo Composites
Additively manufactured NiAl‐CrMo composites contain numerous interfaces and cell boundaries that control their creep response. At 700°C under high applied stress, creep is dominated by dislocation‐controlled power‐law mechanisms. At 800°C–900°C and lower stresses, creep is primarily diffusion‐controlled along cell boundaries.
Jan Vollhüter +9 more
wiley +1 more source
起晕场强是阀厅金具电晕控制的重要依据,针对±800 kV特高压换流站阀厅金具防晕设计裕度过大问题,在海拔高度分别为50 m和4300 m的试验室开展了管母线和屏蔽球的起晕电压试验。利用起晕电压试验、Peek公式和Ansys三维电场仿真计算结果,给出了±800 kV阀厅不同类型金具的防晕最小设计尺寸,并在此基础上提出了阀厅金具表面场强控制建议。建议±800 kV阀厅管形金具等效管径不小于150 mm、球形金具等效球径不小于800 mm、边缘倒角曲率半径不小于30 mm。提出±800 ...
毛艳 +4 more
doaj
The present study investigates recycling of NiTi shape memory alloys via vacuum induction melting. An ingot was synthesized from elemental Ni and Ti and subjected to three subsequent remelting cycles. Remelting increases process durations and impurity levels and adversely affects microstructures and functional properties.
Sakia Sophia Noorzayee +7 more
wiley +1 more source
±800kV云广特高压直流工程孤岛运行方式下整流侧投旁通对逻辑优化特性研究
±800 kV云广直流输电工程是世界上第一个±800 kV特高压直流输电工程,工程起点为云南楚雄换流站,落点为广东穗东换流站,额定电压为±800 kV,输送容量为双极5 000 MW。该工程采用双十二脉动阀组串联接线方式,每个极包括阀组1和阀组2。文中基于±800 kV楚穗特高压直流系统现场孤岛调试以及FPT试验,对孤岛方式下投旁通对逻辑优化前后的系统情况进行对比,验证了整流侧投旁通对逻辑优化的有效性。分析结果表明,在孤岛运行方式下,整流侧禁止投旁通对将有利于系统稳定。
杨珏, 常开忠
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Enhanced Strength and Corrosion Resistance of Ti‐13Nb‐12Ta‐10Zr‐4Sn Alloy by Aging Treatment
This work systematically investigates the effect of aging treatment on mechanical properties and corrosion behavior of vacuum arc‐melted Ti‐13Nb‐12Ta‐10Zr‐4Sn alloy. Owing to the increased α″ martensite, strength and corrosion resistance were significantly enhanced by aging treatment.
Yuhua Li +5 more
wiley +1 more source
根据±800 kV特高压直流输电工程中支持平波电抗器用支柱瓷绝缘子机械、电气、耐地震等性能的要求,较详细地介绍了±800 kV直流系统中平波电抗器用支柱瓷绝缘子的产品设计、试制及试验等研制情况,支柱瓷绝缘子的污秽外绝缘设计,瓷外表面PRTV涂层的特点、优点,耐地震计算分析和性能评价。试验结果表明,所研制绝缘子的机械、电气等特性均能满足±800 kV特高压直流输电工程的要求。还介绍了向家坝-上海±800 kV特高压直流输电工程中平波电抗器用支柱瓷绝缘子及不同电压等级棒形支柱瓷绝缘子在直流场中的应用。
周军
doaj
When two HVDC transmission lines run across, because of the interaction between the two lines, the maximum ground-level total electric field is not a simple superposition of the maximum ground-level total electric field generated when the two lines exist
Fengnyu Xiao +3 more
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In Situ Micromechanical Study of Bimodal γ′–γ″ Precipitate Assemblies in Ni–Cr–Al–Nb Superalloy
A Ni–Cr–Al–Nb superalloy with a bimodal γ′–γ″ precipitate distribution is developed. Composite precipitate assemblies form through heterogeneous nucleation, effectively impeding dislocation motion. Micropillar compression reveals high strength at room and elevated temperatures, governed by precipitate shearing, with coupled faulting mechanisms ...
Ujjval Bansal +4 more
wiley +1 more source

