基于温度场的干式空心电抗器匝间绝缘破损机理研究

Damage Mechanism of Inter-turn Insulation of Dry-type Air-core Reactor Based on Temperature Field

文中为了研究干式空心电抗器产生匝间绝缘破损的内在机理,构建了基于温度场的BKK—20000/63型电抗器三维仿真模型,并依据模型材料特性参数进行了仿真;得到了不同环境下温度场分布图,不同运行电压下各包封平均和最大温升特性曲线,以及不同温度场下各包封热应力分布特性;最后通过实物模型拉伸强度验证了仿真的有效性。通过仿真分析得出干式空心电抗器轴向温度场分布不均,且与运行电压有关,尤其是在环境温度较高或较低时,轴向温度场极不平衡产生的热应力是造成干式空心电抗器局部匝间绝缘破损的根本内在动力。

For studying the internal mechanism of inter-turn insulation damage of dry-type air-core reactors,a 3D simulation model of BKK-20000/63 reactor based on temperature field is constructed. The simulation is performed in accordance with the material characteristics of the model and the temperature field distribution profile in different environments,the characteristic curves of average and maximum temperature rise of each envelope under different operating voltages as well as thermal stress distribution characteristics of each envelope under different temperature fields are obtained. Finally,the validity of the simulation is verified by the tensile strength of the physical model. It is concluded through simulation analysis that the distribution of of axial temperature field of dry-type air-core reactor is uneven,is related to operating voltage and,in case of higher or lower ambient temperature in particular,the thermal stress caused by extreme imbalance of axial temperature field imbalance is the fundamental internal force causing partial inter-turn insulation damage of dry-type air-core reactors.