在电力系统中，电场分布往往不均匀，例如电缆的终端接头部分、绝缘子的端部等等，这些地方的电场强度往往是数倍、甚至几十倍于电场的平均水平，因此成为电力系统的薄弱点。如果不采取措施，则会发生局部放电，造成系统故障。因此，改善系统中的电场分布、抑制极不均匀电场的产生，具有较强的现实意义。我们可以通过对构成部件的绝缘材料本体进行研究改性、改变材料的相关电气参数，来达到改变电场分布的目的。目前绝缘材料有两类，一类是参数固定的材料，及电导率或相对介电常数随电场变化不变的材料。另外一类是参数可变的材料，即非线性压敏电导或者非线性压敏介电材料。COMSOL Multiphysics是基于有限元分析的软件，可以实现多物理场耦合分析。同ANSOFT等材料参数无法变化的软件不同，在COMSOL中我们可以很方便地对材料性质赋予任意函数表达式，适宜本文的非线性参数仿真。在COMSOL中建立了针板电极仿真模型并分别在静电场、交流电流场、直流电流场三种物理场下，分析了电介质材料在固定参数和非线性参数下电场应力的抑制情况。结果表明：在静电场下，材料的介电常数越大，电场的均匀效果越好；交流电流场或者直流电流场下，高电导材料、高介电材料都能起到均匀电场的效果；非线性材料的电导率、介电常数越大，对电场的均匀效果越好。建立了电缆的半导体渗透层模型，仿真分析结果和针板电极模型类似。本文还分别建立了压控管和应力锥两种电缆附件的仿真模型。对于压控管结果表明：相对于高介电材料，压控管采用非线性电导材料对电场应力控制效果更好，但是材料的电导率并非越大越好，应该选择一合适的电导率；避免压控管末端与空气直接接触，形成新的电应力集中。对于应力锥结构，应力锥绝缘部分分别采用非线性电导材料和参数固定的绝缘材料进行对比，结果表明：应力锥绝缘部分采用非线性电导材料后可以有效均匀电场；选择材料并不是电导率越高越好，要综合整个电缆终端的电场分布考虑。

In the power system, the electric field distribution is often uneven, for example, part of the cable terminal connector, insulator ends, etc., where the electric field strength is often several times, even several times the average level of the electric field, thus becoming the power system weak points. If no measures are taken, partial discharge occurs, causing a system failure. Therefore, to improve the system of the electric field distribution, suppress the generation of an electric field is very uneven, with a strong practical significance. We can constitute a part of the insulating material body of research to modify and change the relevant electrical parameters of the material, to achieve the purpose of changing the electric field distribution. Currently there are two types of insulation material, one is fixed parameters of materials, and electrical conductivity or relative permittivity of the material with the constant changes in the electric field. Another one is a material variable parameters, namely non-linear or non-linear conductance sensitive sensitive dielectric material.COMSOL Multiphysics is based on the finite element analysis software, you can achieve multi-physics coupling analysis. ANSOFT and other materials with different software parameters can not change, in COMSOL we can easily impart any function of the material properties of expression, nonlinear simulation parameters suitable herein.The establishment of a needle plate electrode COMSOL simulation model and respectively electrostatic field, alternating current field, direct current field three physics analyzes the dielectric material in the fixed parameters and nonlinear parameters of inhibition of the stress field. The results showed that: In the electrostatic field, for a given electric model, since the complex relationship between the composite and conventional insulating material, the greater the dielectric constant of the composite material, even the effect of the electric field at the intersection of three-phase better; alternating current or direct current field under the flow field, high-conductivity materials, high dielectric materials can play the effect of a uniform electric field; conductivity nonlinear material, the greater the dielectric constant, uniform electric field, the better the effect. The establishment of a semiconductor permeable layer model of the cable, simulation results were similar to the needle plate electrode model.It also established a simulation model were pressing Control Manager and two stress cone cable accessories. The results showed that the pressure Control Manager: with respect to the high dielectric material, press Control Manager conductive material nonlinear stress better control the electric field effect, but conductivity of the material is not always better, you should choose a suitable conductivity; avoid pressure Control Manager terminal direct contact with air, the formation of new electrical stress concentration. Uniform electric field can be effective after the nonlinear stress cone insulation part electrically conductive material; the choice of materials is not higher conductivity: For stress cone structure, stress cone insulation portions are non-linear conductive material and insulating material fixed parameters were compared, the results show better, and comprehensive distribution of the electric field across the cable terminal considerations.