摘要
智能变压器作为智能电网中结构最复杂的电气设备,其事故率高、故障影响明显,对相关绝缘油净化技术提出了高要求。为此,通过改变纺丝电压和聚偏二氟乙烯(PVDF)溶液浓度来提高PVDF纳米纤维的绝缘油净化性能。使用不同浓度的PVDF/二甲基甲酰胺(DMF)溶液在不同电压下进行静电纺丝。傅里叶变换红外光谱(FTIR)和扫描电子显微镜(SEM)结果表明:随着PVDF浓度的增加,PVDF纳米纤维中的α相逐渐减少,β相含量增加;纺丝电压从16kV增至20 kV时,纳米纤维直径减小,分布均匀,当纺丝电压超过20 kV时纤维直径变化趋势相反。在纺丝电压为20 kV和溶液浓度为14%(质量分数)条件下制备的PVDF纳米纤维可将老化油的工频击穿电压提高52.5%,相对介电常数ε_(r)和损耗因子tanδ明显降低,接近新油水平。实验结果表明:电纺PVDF纳米纤维对老化绝缘油具有良好的净化性能,纺丝电压和溶液浓度是优化PVDF纳米纤维净化绝缘油能力的关键因素。
Smart transformers are the most structurally complex electrical equipment in smart grid,with a high accident rate and large failure impact,which places high demands on insulating oil purification.This work aims to improve the oil purification performance of Poly(vinylidene fluoride)(PVDF)nanofibers by variable electrospinning voltages and PVDF solution concentrations.The PVDF/dimethylformamide(DMF)solutions with varying concentrations were utilized for electrospinning at different electric voltages.Results from Fourier-Transform Infrared(FTIR)spectrum and Scanning Electron Microscopy(SEM)show that with the increase of PVDF concentration,the crystallineαphase in the nanofibers gradually decreased,while theβphase got increased.The increased voltage from 16 to 20 kV led to decreased nanofiber diameter and narrowed fiber diameter distribution.However,voltages above 20 k V led to the opposite tendency.After filtration by the nanofibers prepared at 20 kV and 14%concentration,the AC breakdown voltage of the aged oil was enhanced by 52.5%,and the relative permittivityε_(r) as well the loss factor tanδof the aged oil decreased distinctly to the level which is comparable to new insulating oil.The electrospun PVDF nanofibers have shown good performance on the purification of aged insulating oils.The electric voltage and the solution concentration during electrospinning are critical to optimizing the purification performance of the nanofibers.
作者
何潇
周年荣
王飞鹏
黄镜亮
张林山
谭向宇
HE Xiao;ZHOU Nianrong;WANG Feipeng;HUANG Jingliang;ZHANG Linshan;TAN Xiangyu(Electric Power Research Institute of Yumnan Power Grid Co.,Ld.,Kunming 650217,China;State Key Laboratory of Power Transmission Equipment&System Security and New Technology,Chongqing University,Chongqing 400044,China)
出处
《重庆理工大学学报（自然科学）》
CAS
北大核心
2021年第6期195-201,共7页
Journal of Chongqing University of Technology：Natural Science
基金
国家自然科学基金项目(51377176)
中国南方电网科技项目(YNKJXM20190709)。
关键词
智能变压器
绝缘油
纳米纤维
聚偏二氟乙烯
绝缘油净化
smart transformer
insulating oil
nanofiber
poly(vinylidene fluoride)
insulating oil purification
