The effect of high-frequency harmonic voltage on the temperature and electric field of 35 kV cable termination is investigated and the relationship between hot spot and electric field distribution is analyzed. Voltages of different frequencies are exerted on the cold-shrinkable cable terminations of two types (stress grading and geometric) and it is found that,along with the increase of frequency,there are obvious hot spots on the stress grading termination,which are corresponding to the concentrating spots of electric field,while there is no obvious temperature change on the geometric termination. The electric aging test indicates that,along with the increase of aging time,the hot spot temperature of stress grading termination rises obviously while that of geometric termination is not so obvious.%研究了高频谐波电压对35 kV电缆终端温度和电场的影响规律,分析了热点和电场分布之间的联系.首先,对2种不同类型的冷缩电缆终端(应力均匀型和几何型)施加不同频率的电压,通过红外热成像发现,随着谐波频率增加,应力均匀型终端形成明显的热点,而几何型终端温度变化不明显.通过有限元分析发现,应力均匀型终端的热点位置与电场集中点相对应.此外,通过持续工频叠加高频电压电老化实验发现,老化时间增长,应力均匀型终端的热点温度明显增长,而几何型终端则增长略小.
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