10 kV 并沟线夹温升诱发机制的多物理场耦合研究

并沟线夹是带电作业中最常用的接续金具之一,针对并沟线夹容易因接触力不足、发热不均匀等原因而出现过热甚至烧毁的现象,文章建立并沟线夹的等比例多物理场仿真模型,在不同安装扭矩下,对其不同部位的电流密度、欧姆损耗和温度分布进行分析。结果表明,主导线和副导线与并沟线夹接触区域的电流密度及欧姆损耗的分布极不均匀,其中与副导线接触的并沟线夹下夹块接触区域欧姆损耗最高,达到 $ 19.6\ MW/m^{3} $,由于电流密度和欧姆损耗分布不均匀,温度最高点也出现在与副导线接触的并沟线夹下夹块上。根据不同安装扭矩下的温度仿真结果可知,并沟线夹的温度随安装扭矩的增大而减小并最终趋于稳定,为了保证线夹在运行中的可靠性,螺栓的扭矩应保持在 $ 16\ N\cdot m $以上。

Parallel groove clamp is one of the most commonly used connection fittings in electrification. In view of the phenomenon that parallel groove clamp is easy to overheat or even burn out due to insufficient contact force and uneven heating, this paper established the equal proportion multi-physical field simulation model of parallel groove clamp. Under the conditions of different installation torques, the current density, ohmic loss and temperature distribution at different parts of the parallel groove clamp were analyzed. The results show that the distribution of current density and ohmic loss in the contact area between the main conductor and auxiliary conductor and the parallel groove clamp is extremely uneven. The ohmic loss in the contact area of the lower clamp block of the parallel groove clamp in contact with the auxiliary conductor is the highest, reaching $ 19.6 \, MW/m^3 $. Due to the uneven distribution of current density and ohmic loss, the highest temperature point also appears on the lower clamp block of the parallel groove clamp in contact with the auxiliary conductor. According to the temperature simulation results under different installation torques, the temperature of the parallel groove clamp decreases with the increase of installation torque and finally tends to be stable. In order to ensure the reliability of clamp in operation, the torque of bolt should be kept above $ 16 \, N \cdot m $.