金属聚合物复合材料的电树枝生长模拟

Simulation of Electrical Tree Growth in Metal-loaded Composites

为了研究金属聚合物复合材料的击穿特性,在WZ模型的基础上建立了在绝缘聚合物介质中填充不同体积浓度的理想金属粒子的逾渗模型。利用计算机对放电通道的发展进行仿真,并对得到的仿真图形进行比较,研究了金属颗粒的体积浓度、下极板施加的电压、放电通道内的阈值电压和树点发展的概率指数对放电通道发展的影响。结果表明,金属粒子体积浓度越大,则放电树枝分枝越多。因此,填充金属颗粒可以明显地增强绝缘介质的导电性,其中逾渗阈值为0.6。下极板施加的电压越大,放电通道内的阈值电压和树点发展的概率指数越小,则放电树枝分枝越多,同时放电树枝生长过程中的积累损伤越大,该规律与实际放电情况相符合。

Based on the WZ model,a percolation model of metal-loaded composites is simulated in different volume concentrations of metal particles to investigate its dielectric breakdown characteristics.By comparing with the simulation figures,the effects of model parameters on the development of the electrical trees are discussed,such as different volume concentrations of metal particles,electric potential,threshold voltage and probability exponent.The results present that with the increase of volume concentration of metal particles,the number of branches increases.Therefore,the conductivity of insulation material is significantly enhanced by metal particles and the percolation threshold is 0.6.In addition,with the increase of electric potential and the decrease of the threshold voltage and the probability exponent,the number of branches and accumulated damage increase.The result of the characteristic of electrical tree conforms to the actual conditions.