高压电缆在电压极性反转过程中的空间电荷行为研究

Study on the Space Charge Behavior of High-Voltage Cables During Voltage Polarity Reversal

为探明同轴结构交联聚乙烯(XLPE)电缆绝缘在外施电压极性反转过程中的空间电荷注入、迁移、抽出等动态演变规律,分析外施电压极性反转过程中空间电荷导致的反转“滞后效应”,并探究温度梯度协同作用的影响规律,对XLPE电缆进行了不同电场强度、温度梯度场下,外施电压快速极性反转过程中的空间电荷研究,并基于异极性电荷注入、迁移理论,对极性反转过程中电缆绝缘空间电荷的演变规律进行分析。研究结果表明:XLPE电缆在外施电压快速反转过程中,由于电缆绝缘内部残余电荷的影响,电缆两侧电极电荷峰表现出不平衡的反转特性,导致电缆外半导电层电极的电荷峰出现了明显的反转“滞后效应”。

In order to find out the dynamic evolution rules of space charge injection,migration and extraction in the process of polarization reversal of coaxial structure cross-linked polyethylene(XLPE)cable insulation under applied voltage,this paper analyzes the“hysteresis effect”of the inversion of space charge caused by the polarity reversal of the applied voltage,and explores the influence law of temperature gradient synergism.The space charge of XLPE cable in the process of rapid polarity reversal of applied voltage under different electric field strengths and temperature gradient fields was studied,and based on the theory of heteropolar charge injection and migration,the evolution law of cable insulation space charge in the process of polarity reversal is analyzed.The results show that during the XLPE cable rapid reversal of applied voltage process,the charge peaks of the electrodes on both sides of the cable show an unbalanced reversal characteristic due to the influence of the residual charge inside the cable insulation,which leads to the obvious reversal“hysteresis effect”of the charge peaks of the semi-conductive layer electrodes outside the cable.