摘要
高压直流电缆附件在电力系统运行中,由于复合绝缘电导率不匹配极易导致电场畸变引发绝缘故障。针对这一问题,采用直接共混法制备了不同掺杂浓度的纳米TiO_2/液体硅橡胶(LSR)复合材料,并对其微观形貌和介电性能进行了测试研究。结果表明:纳米TiO_2粒子在LSR基体中分散较均匀,随着TiO_2掺杂含量的增加,纳米TiO_2/LSR复合材料试样的相对介电常数和介质损耗因数增大。当纳米TiO_2粒子添加量为4wt%时,纳米TiO_2/LSR复合材料的电导率与电缆主绝缘交联聚乙烯(XLPE)的电导率近似相等,且随着电场强度的增大,两者的电导率变化趋势也基本一致。电声脉冲法(PEA)测量结果表明,添加4wt%TiO_2的纳米TiO_2/LSR复合材料内积聚的空间电荷最少。纳米TiO_2粒子的掺杂,提高了TiO_2/LSR复合材料电缆附件绝缘电导率对电场强度的响应依赖特性,使其能与XLPE绝缘电导率较好地匹配,同时一定程度地抑制了空间电荷的积累,有助于直流电缆附件内复合绝缘电场的均匀分布。
In the operation of power system,the electric field in high voltage direct current cable accessories was easily distorted and even leades to insulation failure-which was caused by the conductivity of composite insulation materials mismatched.In order to solve this problem,the nano TiO2/liquid silicone rubber(LSR)composites with different components for cable accessories insulation were prepared,and the microstructure and dielectric properties were tested.The results show that nano TiO2 particles disperse uniformly in LSR matrix.With the increase of TiO2 nanoparticles doping content,the relative permittivity and dielectric loss constant of nano TiO2/LSR composites are in creased,while the breakdown strength decreases.The conductivity of nano TiO2/LSR composites is approximate-ly equal to that of cable ontology insulation crosslinked polyethylene(XLPE),when the nano TiO2 doping content is 4wt%.Moreover,the trend of the conductivity changes of the two materials is basically the same,as the electric field strength increases.The pulsed electroacoustic apparatus(PEA)test result shows that 4wt%TiO2/LSR com-posites accumulated space charge is the least.The doping of TiO2 nanoparticles improves the electric field dependent coefficient of conductivity of cable access-ories insulation,and it can inhibit the accumulation of space charge to some extent.It makes the composite insulation achieve a good match,which can promote the electric field distribution uniform in the direct current cables accessories composite insulation.
作者
尚南强
陈庆国
秦君
SHANG Nanqiang;CHEN Qingguo;QIN Jun(Key Laboratory of Engineering Dielectrics and Its Application,Ministry of Education,School of Electrical and Electronic Engineering,Harbin University of Science and Technology,Harbin 150080,China)
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2019年第1期104-113,共10页
Acta Materiae Compositae Sinica
基金
国家自然科学基金(51407051)
黑龙江省自然科学基金(ZD201310)
关键词
电缆附件
纳米TiO2/液体硅橡胶
复合材料
电导率
空间电荷
电场分布
cable accessories
nano TiO2/liquid silicone rubber
composites
conductivity
space charge
electric field distribution
