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500kV直流断路器快速机械开关典型故障特性及可靠性提升方法研究 [PDF]
全球能源互联网, 2023 直流断路器是构建柔性直流电网不可或缺的关键设备。快速机械开关是直流断路器中承载电流、实现快速分合闸、耐受分闸恢复电压的核心组件，其结构复杂、动作速度快、电气应力严酷、可靠性要求高，因而设计研制难度大，任一环节出现问题均会影响直流断路器乃至柔直电网的安全可靠运行。然而，目前快速机械开关由于存在设计选型不合理、工艺管控不严格、试验考核不完善等问题，导致在实际工程应用中故障率较高。针对已应用于张北柔性直流电网试验示范工程的500 kV直流断路器，分析了直流断路器研制、调试 ...
魏争 +4 more
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Gaoya dianqi, 2021 快速机械开关作为500 kV混合式高压直流断路器的核心部件之一,要求在2 ms内分闸,并耐受高达800 kV暂态分断电压,其2 ms内分闸耐压的速动性是混合式高压直流断路器对快速机械开关提出的核心技术要求,也考验了快速机械开关自身缓冲装置的可靠制动能力。考虑快速机械开关需满足高压直流断路器快速重合闸功能设计,传统的液压油缓冲、聚酯氨缓冲和气体缓冲均无法满足快速重合闸工况下的二次缓冲问题,文中分析了500 kV混合式高压直流断路器快速机械开关的快速分合闸、重合闸等运行工况 ...
张宁 +6 more
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集成气体缓冲的单断口72.5 kV快速真空开关运动质量对分闸特性的影响
Gaoya dianqi, 2021 快速真空开关可实现电力系统短路故障的快速切除,对电力系统运行暂态稳定性的提升具有重大意义,是现阶段国内外大电流开断技术领域研究热点。文中目标是确定集成气体缓冲快速真空开关传动系统运动质量对其分闸特性的影响。文中以72.5 k V单断口快速真空开关为研究对象,采用多物理场仿真计算方法,建立了气流场、电磁场、运动方程和外电路相互耦合的多物理场仿真计算模型,分析了快速真空开关运动质量对其分闸速度、动量、缓冲反力特性等分闸特性的影响,其中分闸速度为快速真空开关分闸过程触头分离后10 mm内的平均速度 ...
樊益平 +7 more
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Role of funders in embedding tests in conservation practice
Conservation Biology, EarlyView.Abstract Effective conservation practice requires decisions based on reliable and relevant evidence, but significant gaps in the evidence base exist. Incorporating well‐designed tests of the effectiveness of interventions for biodiversity in conservation projects is one of the best ways to scale up the rate of evidence generation.
Rebecca K. Smith +28 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT LiBH4 has drawn significant attention due to its high theoretical hydrogen storage capacity of 18.5 wt%, yet its practical application is hindered by the harsh dehydrogenation conditions. This paper proposes a strategy integrating ensemble learning with density functional theory (EL–DFT) for rapidly screening modified LiBH4 systems that ...
Zishan Luo +11 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Metal‐organic frameworks (MOFs) hold significant potential across numerous advanced disciplines due to their exceptional properties, including high specific surface area, tunable porosity, structural diversity, and customizable functionality. Increasing attention has been directed toward employing MOFs in coatings that offer both antimicrobial
Yanchun Zhao +7 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Catalytic NH3 decomposition has garnered substantial attention for hydrogen transformation and storage. Ni‐based catalysts continue to suffer from limited thermal stability and suboptimal low‐temperature activity, largely attributed to an incomplete understanding of the structure‐activity relationships and reaction mechanisms governing their ...
Tao Wen +8 more
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Functional Ecology, Volume 40, Issue 6, Page 1878-1891, June 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Ecological communities are stressed by rapid and complex anthropogenic changes, threatening the persistence of biotic interactions and ecosystem functioning. Plant–pollinator communities, for instance, undergo structural transformations as a result of land‐use change ...
Erliang Gao +8 more
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Gaoya dianqi, 2016 直流快速开关作为大容量直流供电系统安全运行的保证,其开断的分闸速度与开断的固有分闸时间直接影响到直流快速开关的快速性与合理可靠性。文中通过研究直流快速开关斥力机构工作原理,分析现有直流快速开关机构操动机构、保持机构、缓冲机构的结构形式与优缺点,总结出了直流快速开关斥力机构的2种操作机构,2种保持机构,4种缓冲机构的结构形式。根据研究成果给出直流快速开关机构设计的单线圈斥力+单线圈永磁保持以及双线圈斥力+碟簧保持两种典型方案,为直流快速开关机构的设计与试验提供了指导原则,也可为其他相关工程提供参考。
贾伟, 牛万宇, 王瑞, 左利博
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Gaoya dianqi, 2021 电磁斥力机构是快速机械开关的核心部件,在快速合闸和分闸过程中巨大的电磁驱动力会给电磁斥力机构和整个机械传动系统带来强烈的瞬态冲击。针对该问题,文中对电磁斥力机构在合闸和分闸全过程中的机械特性和结构强度进行了研究。采用LS-DYNA建立快速机械开关的有限元仿真计算模型,并求解得到合闸和分闸全过程各零部件的机械运动特性和瞬态冲击强度。采用激光测距对某单断口快速机械开关进行了实验测量,得到合闸和分闸过程的时间—行程特性曲线,实验测量结果和仿真计算结果匹配良好。最后对仿真计算模型进行参数优化,从而降低合闸弹跳 ...
熊杰, 刘彬, 于海波, 刘国伟
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