Results 51 to 60 of about 228 (102)

基于频谱余弦距离的光伏系统串联电弧故障检测方法

open access: yesGaoya dianqi
光伏系统中发生电弧故障时,故障信号容易受到光照强度变化等因素影响,且高频故障信号会随线缆传播而衰减,导致光伏系统串联电弧故障难以检测。现有光伏系统电弧故障检测方法中,对大电流、长距离线缆条件下的故障检测研究不足,且缺乏真实光伏系统电弧故障检测的有效性验证。为了有效检测光伏系统出现的电弧故障,首先搭建了低压直流系统和光伏系统电弧故障实验平台,通过串联拉弧实验获取电弧故障数据。然后,利用快速傅里叶变换(fast Fourier transform,FFT)对电弧故障发生前后的频谱进行分析 ...
郭佳豪   +8 more
doaj  

基于光学测量系统的高压断路器铜钨弧触头烧蚀特性研究

open access: yesGaoya dianqi
高压SF6断路器具有关合、承载、开断额定电流和故障电流的能力,在维护电力系统安全稳定运行方面发挥着重要作用。然而,断路器触头在电弧烧蚀作用下寿命不断降低,进而导致开断失败,因此研究弧触头的烧蚀特性对开发电寿命监测系统有重要意义。文中基于高速摄影仪、高速光谱仪、光纤传感器等光学测量系统,对电弧弧根的宏观移动特性进行了观测。通过分析触头表面形态图像和质量损失,探究了铜钨触头在不同开断电流等级下的烧蚀特性。研究发现,随着开断电流的增大,弧根直径逐渐扩大,电弧在触头表面的移动性却降低 ...
牛博   +10 more
doaj  

[Evaluation of Gradient-Variant Quantum Dot Fluorescence Technology for Rapid Detection of <i>Brucella</i>]. [PDF]

open access: yesSichuan Da Xue Xue Bao Yi Xue Ban
Li J   +9 more
europepmc   +1 more source

[Clinical efficacy of two-stage ear reconstruction using autologous rib cartilage in the correction of congenital microtia]. [PDF]

open access: yesZhonghua Shao Shang Yu Chuang Mian Xiu Fu Za Zhi
Xu ZC   +6 more
europepmc   +1 more source

[Comparative study on accuracy of three imaging methods in diagnosis of subacromial impingement syndrome]. [PDF]

open access: yesZhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
Zi L   +7 more
europepmc   +1 more source

[Tympanic membrane repair using improved endoscopic ear canal flap dissection method]. [PDF]

open access: yesLin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
Sun H, Song R, Yu Z.
europepmc   +1 more source

Home - About - Disclaimer - Privacy