The Maxwell–Wagner model and bipolar charge transport model both aim at describing the charge transport behaviours in dielectrics. The Maxwell–Wagner model performs well in calculating the polarisation current and electric field distribution, but it is too macroscopic to describe the microscopic behaviours of space charges. The bipolar charge transport model can well simulate the space charge accumulation, but it cannot quantitatively relate the microscopic transport behaviours with the macroscopic conductivities of dielectrics. Considering the shortages of the above two models, an improved charge transport model, named carrier dynamic equilibrium model, was proposed in this study to simulate the polarisation process of the low-density polyethylene/ethylene propylene diene monomer bi-layer dielectric by introducing a source term of carrier dynamic equilibrium. Effects of carrier mobility and non-equilibrium carrier lifetime on the simulation results were explored, and a comparison among the results of measurement and different models was also made. Compared with the Maxwell–Wagner model and bipolar charge transport model, the improved model has the best coincidence with measurements, which can provide an accurate reference for the design of high-voltage direct current insulation systems.

中文翻译：

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考虑到载流子动态平衡的双层介电中改进的空间电荷传输模型

Maxwell–Wagner模型和双极电荷传输模型都旨在描述电介质中的电荷传输行为。麦克斯韦-瓦格纳模型在计算极化电流和电场分布方面表现良好，但它无法从宏观上描述空间电荷的微观行为。双极电荷传输模型可以很好地模拟空间电荷的积累，但不能将微观传输行为与电介质的宏观电导率定量地联系起来。考虑到上述两个模型的不足，一种改进的电荷传输模型，称为载流子动态平衡模型，在这项研究中提出通过引入载流子动态平衡的源项来模拟低密度聚乙烯/乙烯丙烯二烯单体双层电介质的极化过程。探索了载流子迁移率和非平衡载流子寿命对仿真结果的影响，并对测量结果与不同模型进行了比较。与麦克斯韦-瓦格纳模型和双极电荷传输模型相比，改进后的模型与测量具有最佳的重合性，可以为高压直流绝缘系统的设计提供准确的参考。