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高温高场的运行环境会影响高压直流电缆绝缘层中杂质的解离、电荷的注入和迁移过程,为了研究温度和外施电场对交联聚乙烯空间电荷行为的影响,测量了最高温度为80℃,最高场强为90kV/mm的交联聚乙烯片状试样的空间电荷分布特性.研究表明:外施电场越强,电荷注入越多;温度越高,电荷的迁移率也越高,80℃时的迁移率比20℃的迁移率大一个数量级;20℃时出现了明显的空间电荷包现象,绝缘层中空间电荷积累较多,随着温度的升高空间电荷包现象消失,绝缘层中空间电荷积累减少.这说明温度对空间电荷迁移的促进作用比空间电荷注入和杂质解离的促进作用更强,使得高温下空间电荷包难以形成,且难以在绝缘层中积累过多的空间电荷.“,”The high operation temperature caused by Joule heat and high electric field can influence the ionic dissociation,charge injection and migration process in the high voltage cable.To study the effect of temperature on the space charge behavior in cross-linked polyethylene,this paper presented the measurement results of space charge distribution in flat sample based on pulsed electro-acoustic measurement (PEA) principle.The temperature ranged from 20℃ to 80℃ and the electric field reached up to 90 kV/mm.It is shown that high electric field intensifies the injection of charge and high temperature accelerates the migration of charge.The apparent mobility of charge at 80℃ has a larger magnitude than that at 20℃.The space charge packets are observed in the sample at 20℃ whereas it is seldom to observe the space charge packets formation at relatively higher temperature.Besides,less space charges accumulate in the insulation layer at higher temperature.It indicates that the enhancement of charge migration is stronger than that of the ionic dissociation and charge injection at higher temperature.