Results 41 to 50 of about 239,675 (149)
Gaoya dianqi, 2017 文中介绍了126 kV单断口真空断路器的操作过电压现场测试结果。首先,确定断路器应用场所并设计了过电压测试方案;然后,测试真空断路器和SF6断路器切合变压器的操作过电压并进行对比;最后,测试真空断路器切合空载线路操作过电压。通过测试,真空断路器和SF6断路器切合变压器的操作过电压水平基本接近,切合空载变压器时无过电压,而带载变压器操作过电压可达1.46倍;真空断路器切合空载变压器的过电压分别可达1.34倍和1.25倍。
全伟 +4 more
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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
Dianci bileiqi, 2019 雷电感应过电压导致配电线路发生跳闸或故障的比例要远高于雷电直击,因此需要分析采用线路避雷器对配电线路感应过电压的防护效果。利用EMTP软件编程计算线路雷电感应过电压,分析安装线路避雷器对感应过电压的防护效果,讨论雷电流幅值和雷击点距线路距离、避雷器安装间距、接地电阻对避雷器抑制感应过电压效果的影响。分析结果表明:配电线路安装线路避雷器后能够在一定程度抑制雷电感应过电压;雷电流幅值越高、雷击点距线路近,避雷器抑制感应过电压的效果越弱;避雷器安装间距影响对感应过电压的防护效果,安装越密 ...
罗永志, 王艳辉
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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
基于ATP-EMTP的真空断路器切断并联电抗器过电压及其抑制策略分析
Gaoya dianqi, 2016 真空断路器在切断并联电抗器时伴随着截流过电压、多次重燃过电压等危害,造成电力系统的不稳定运行。为此,文中基于ATP-EMTP软件首先对变电站实际运行情况进行仿真分析,发现了在母线侧、负载侧以及电抗器侧存在着严重的相对地过电压以及相间过电压。随后通过结合过电压种类以及严重程度,选择了不同的保护装置并对保护效果进行仿真分析,得出双路RC过电压保护装置对于真空断路器切断并联电抗器产生的过电压具有较好的抑制效果。最后根据变电站的实际运行情况,对采取不同保护装置安装措施后过电压情况进行仿真计算 ...
王利婷
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, 1986 电压--频率变换器,它具有一个由差分放大器构成的积分器,一个电平可控脉冲发生器,一个开关控制器和一个精密电荷分配器.该精密电荷分配器是由三个开关,一个定电荷电容,一个参考稳压管,一个充电电阻及一个负电源组成的.该定电荷电容放完电后,通过上述充电电阻,在上述差分放大器的反相输入端和上述负电源之间积分充电到上述参考稳压管的击穿电平而完成定电荷的.较之已有的积分定电荷反馈复原型电压--频率变换器的定电荷方式优越,提高了变换器的精度,稳定性和高频性能 ...
唐军
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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
Dianci bileiqi, 1981 随着输电电压的提高,操作过电压比大气过电压显得更重要,尤其是超高压系统。操作过电压的绝缘配合问题,引起了有关方面的很大注意。为了有效地降低超高压系统中电气设备的操作过电压绝缘水平,必需对避雷器的限制操作过电压能力开展研究。因而,避雷器在操作过电压下的续流遮断特性和试验方法,也就成了重要的问题。近年来,各国对避雷器在操作过电压（主要是合闸长线过电压）下的灭弧能力以及操作过电压下的续流试验方法进行了大量的研究工作 ...
龙淑范, 张雨时
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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
基于真空断路器预击穿特性的海上风电场集电网合闸暂态过电压仿真研究
Gaoya dianqi, 2019 海上风电场中压电缆集电系统真空断路器在闭合空载变压器操作中,真空断路器预击穿会在机端变压器的高压侧产生暂态过电压,该过电压与电缆作用产生高频振荡过电压将对变压器绝缘产生损坏。文中研究真空断路器预击穿产生高频暂态过电压的机理,在PSCAD/EMTDC暂态分析软件上搭建真空断路器预击穿现象的自定义模型,并将此模型应用于简化的海上风电场中压电缆集电系统模型,研究合闸初相角、电缆长度和机端变压器位置对暂态过电压的影响。仿真结果表明机端变压器位于机舱且合闸初相角为15°过电压陡度最大 ...
吴俊臣 +3 more
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