Results 1 to 10 of about 190,254 (168)
考虑谐波谐振和电压稳定的海上风电场无功优化配置方法 [PDF]
, 2023 海上风电经长距离高压交流海底电缆接入电网，海底电缆容升效应显著，容易引起工频过电压，同时电力电子器件和线路电容引起的谐波谐振问题也严重影响着电网电能质量，因此进行海上风电场无功配置时应充分考虑过电压和谐波谐振问题。针对上述问题，建立了海上风电场谐波模型，对海上风电场的谐波模态阻抗进行扫描，继而分析海上风电场的谐振特性；然后研究了海上风电场无功特性，计算各种发电出力水平和并网点电压下的风电场无功缺额；接着以降低综合成本为目标，以静态电压稳定裕度、最小补偿容量、谐波谐振及过电压为约束 ...
马明, 梅桂华, 杜婉琳*, 王玲
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适用于直流配电网故障选线的电力电子变压器分步闭锁方案 [PDF]
, 2023 级联H桥型电力电子变压器（power electronic transformer with cascaded H-bridge，CHB-PET）是柔性变电站的重要组成设备之一，在直流配电网中具有重要作用。当CHB-PET低压直流侧发生双极短路故障后，故障电流上升速度快且幅值较高，易导致电力电子器件迅速闭锁，使低压直流电网保护难以准确获取故障信息。针对CHB-PET低压侧多分支直流配电网，提出一种基于PET分步闭锁的故障穿越策略。当检测到PET低压侧直流系统故障后 ...
于弘洋 +5 more
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Gaoya dianqi, 2021 高压断路器切除并联电抗器时会产生较高的过电压,而导致设备故障,危及电网安全运行。文中从开断电抗器产生过电压的原理出发,并结合试验结果分析过电压的区间分类,提出了重燃窗口以及过电压临界点的划分方法,详细分析了选相分闸技术抑制过电压的原理,并通过试验验证其可有效控制过电压在较低水平,从而消除过高的过电压对电力设备的威胁。
陈杳伟, 史俊, 党德旺, 付杰
doaj
Dianci bileiqi, 2021 风力发电机遭受雷击时,塔筒内控制电缆、塔基处以及箱式变压器低/高压侧都会出现过电压,且过电压还会通过集电电缆和联合接地装置传到其他风电机组。为研究雷击风电场时引起的暂态电压,建立了包含风力发电机、集电电缆、箱式变压器的等效模型。考虑了雷电流参数、风力发电机接地电阻大小及风电场拓扑结构对风电场过电压影响。结果表明:单台风电机组遭受雷击的情况下,风电机组过电压值与雷电流幅值成正比,且波前时间为8.0μs和20.0μs时,雷电流幅值对控制电缆缆芯过电压影响很小;风电机组过电压值与波前时间成反比 ...
罗永志 +5 more
doaj
Gaoya dianqi, 2023 雷电感应过电压是引起配电网故障的主要因素之一。为收集配电线路上的感应雷过电压数据，研究其波形特性，以期用于指导架空配电线路的雷电防护，文中采用了一个自供电、无线传输的雷电过电压在线监测装置，接触测量了配电线路中雷电感应过电压信号。通过对某10 kV配电线路上雷电感应过电压波形进行观测，并根据波形特征获取过电压相关波形参数。结果显示，感应雷过电压主要以高频分量形式叠加至工频相电压，所观察到的感应雷过电压波表现为波头时间短、波尾出现双极性高频振荡，最终衰减到零的特点 ...
徐文华 +7 more
doaj
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Biodegradable Zn‐based alloys are promising candidates for temporary implants, yet excessive Zn2+ release during degradation may induce cytotoxicity and adverse tissue responses. In this study, Zn‐xBa alloys (x = 0.1 wt%, 0.5 wt%, 1.0 wt% and 3.0 wt%) were developed to achieve controlled corrosion behaviors with improved biocompatibility.
Liu‐Dang Fang +9 more
wiley +1 more source
Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Achieving a simultaneous enhancement in both tribological and mechanical properties of self‐lubricating composites has long been a challenge. In this study, we designed the composition based on first‐principles calculation and fabricated a copper‐based self‐lubricating composite with excellent tribological and mechanical properties via spark ...
Zhongbo Wang +4 more
wiley +1 more source
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Managing diabetic wounds requires simultaneously addressing their infectious, oxidative, and regenerative impairments. To address this, this study integrates a piezoelectric BiOCl@CuSe heterojunction (PFM‐verified) into an injectable F127/HA hydrogel, creating an ultrasound‐responsive smart dressing.
Jiayan Guo +5 more
wiley +1 more source
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Sodium metal batteries hold significant promise for large‐scale energy storage due to the high theoretical capacity and abundant sodium sources, yet sodium‐metal anodes are hindered by dendrite propagation, unstable solid electrolyte interphase, and poor cycling efficiency arising from uneven Na deposition and volume changes.
Nan Xing +7 more
wiley +1 more source
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Additive manufacturing, commonly referred to as three‐dimensional (3D) printing, provides the geometric freedom and multi‐material integration needed to build soft medical robots for minimally invasive interventions, prosthetics, and rehabilitation.
Yao Wang +5 more
wiley +1 more source