不同压力和温度下电缆用乙丙橡胶绝缘的极化电流研究

Study on polarization current of EPDM insulation for power cable underdifferent pressure and temperature

为了研究压力和温度对电缆用乙丙橡胶绝缘电导性能的影响,本研究测量了不同电场强度、温度和压力下乙丙橡胶的极化电流,提取极化指数和电导率,分析了乙丙橡胶的性能变化规律。基于准稳态电导电流密度与电场强度的关系,研究了压力和温度对乙丙橡胶导电机制的影响。结果表明:极化指数和电导率与温度呈线性相关性,而与压力呈非线性相关性。这是因为受压力和温度影响,乙丙橡胶的导电机制发生了变化,温度升高可以促进乙丙橡胶中的载流子数目增多。较低的压力限制了乙丙橡胶分子间的运动,较高的压力会破坏分子链,导致电导率升高。

In order to study the effects of pressure and temperature on the conductivity of ethylene propylene rubber(EPDM)insulation for cables,the polarization current of EPDM under different electric field,temperature,and pressure were measured.The polarization index and conductivity were extracted,and the change law of the performance of EPDM was analyzed.The effect of pressure and temperature on the conduction mechanism of EPDM on pressure and temperature was studied based on the relationship between quasi-steady-state conductance current density and electric field intensity.The results show that the polarization index and conductivity are linearly related to temperature,but nonlinear related to pressure.This is because the conduction mechanism of EPDM changes under the influence of pressure and temperature,and the increase of temperature can promote the increase of the number of carriers in EPDM.The lower pressure limits the intermolecular movement of EPDM,while the higher pressure can destroy the molecular chain,resulting in an increase in electrical conductivity.