极性反转下低密度聚乙烯空间电荷动态特性的数值模拟
发布时间：2019-01-04 23:16
【摘要】：直流电缆在运行时如果电压极性发生反转,会使得外加电场与累积空间电荷所产生的电场叠加而增强,可能引起局部放电或介质击穿。目前的实验测量方法无法揭示极性反转过程中空间电荷和电场的瞬态变化,尤其是微观粒子之间的相互作用过程。为了深入研究高压直流电缆在极性反转下的内绝缘机理,利用双极电荷传输模型对低密度聚乙烯(LDPE)的空间电荷动态特性进行了数值模拟,并通过仿真研究了多次极性反转下LDPE空间电荷和电场的瞬态分布。结果表明:极性反转时表面电场大大增强,并具有一定的极性效应,在由阳极转变为阴极时更加显著;极性反转前陷阱电荷密度远大于自由电荷密度,极性反转时电极表面电场的增强主要是由电极附近的陷阱电荷所决定。研究成果可为高压直流电缆的绝缘设计提供参考,也可以为聚合物材料空间电荷的动态仿真提供借鉴。
[Abstract]:If the voltage polarity is reversed during the operation of DC cable, the electric field produced by the applied electric field and the accumulated space charge will be superimposed and strengthened, which may cause partial discharge or dielectric breakdown. The current experimental methods cannot reveal the transient changes of space charge and electric field in the process of polarity inversion, especially the interaction between microparticles. In order to deeply study the internal insulation mechanism of HVDC cable under polarity reversal, the space charge dynamic characteristics of LDPE (LDPE) were numerically simulated by bipolar charge transfer model. The transient distribution of LDPE space charge and electric field under multiple polarity inversion is studied by simulation. The results show that the surface electric field increases greatly and has a certain polarity effect when the polarity is reversed, and it is more obvious when the anode is changed to the cathode. The trap charge density is much larger than the free charge density before polarity inversion, and the enhancement of the electric field on the electrode surface is mainly determined by the trap charge near the electrode. The results can be used as a reference for the insulation design of HVDC cables and for the dynamic simulation of space charge of polymer materials.
【作者单位】： 福州大学电气工程与自动化学院;清华大学电机工程与应用电子技术系;
【基金】：国家重点基础研究发展计划(973计划)(2014CB239500)~~
【分类号】：TM215.1
[Abstract]:If the voltage polarity is reversed during the operation of DC cable, the electric field produced by the applied electric field and the accumulated space charge will be superimposed and strengthened, which may cause partial discharge or dielectric breakdown. The current experimental methods cannot reveal the transient changes of space charge and electric field in the process of polarity inversion, especially the interaction between microparticles. In order to deeply study the internal insulation mechanism of HVDC cable under polarity reversal, the space charge dynamic characteristics of LDPE (LDPE) were numerically simulated by bipolar charge transfer model. The transient distribution of LDPE space charge and electric field under multiple polarity inversion is studied by simulation. The results show that the surface electric field increases greatly and has a certain polarity effect when the polarity is reversed, and it is more obvious when the anode is changed to the cathode. The trap charge density is much larger than the free charge density before polarity inversion, and the enhancement of the electric field on the electrode surface is mainly determined by the trap charge near the electrode. The results can be used as a reference for the insulation design of HVDC cables and for the dynamic simulation of space charge of polymer materials.
【作者单位】： 福州大学电气工程与自动化学院;清华大学电机工程与应用电子技术系;
【基金】：国家重点基础研究发展计划(973计划)(2014CB239500)~~
【分类号】：TM215.1
【参考文献】
相关期刊论文 前5条
1 朱庆东;吴锴;朱文兵;李杰;;温度梯度下油纸绝缘空间电荷特性的数值仿真[J];高电压技术;2016年03期
2 雷清泉;李盛涛;;关于工程电介质中几个经常涉及的问题与思考[J];高电压技术;2015年08期
3 何金良;党斌;周W，
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