高压开关柜三维瞬态电场计算研究

Research on 3D Transient Electric Field Calculation of High⁃voltage Switchgear

高压开关柜运行过程中承受的不均匀电场将会导致绝缘介质内部或表面出现高场强区域,危害电力设备的安全可靠运行。针对12 kV铠装型移开式交流金属封闭开关设备,文中利用Ansys Maxwell建立了开关柜电缆室三维瞬态电场有限元仿真模型,获得了开关柜电缆室在10 kV系统标称电压下的电场分布特征和电场集中区域。在此基础上,研究了不同母线电压值、三相电压不平衡对触头盒、避雷器、接地开关支柱绝缘子以及母线相间处最大电场强度单元节点的影响。仿真结果表明:触头盒内部、避雷器高压端、接地开关支柱绝缘子与静触头接触处电场较为集中,且不同母线电压值、三相电压不平衡对上述部件所承受的瞬态电场影响很大。文中电场仿真结果对改善开关柜内部电场分布、现场运行维护具有一定参考价值。

During the operation of the high⁃voltage switchgear,the uneven electric field will cause a high field strength area inside or on the surface of the insulating medium,which will endanger the safe and reliable operation of the power equipment.Aiming at the 12 kV armoured removable AC metal enclosed switchgear,this paper uses An⁃sys Maxwell to establish a three⁃dimensional transient electric field simulation model of the switchgear cable room,and obtains the electric field distribution characteristics and electric field concentration area of the switchgear cable room at the 10 kV system nominal voltage.Based on this,the effects of different bus voltage values and three⁃phase voltage imbalances on the contact box,arrester,grounding switch post insulator,and the node of the largest electric field strength between the bus bars are studied.The simulation results show that the electric field inside the contact box,the high⁃voltage side of the arrester,and the contact between the grounding switch pillar insulator and the static contact is more concentrated.What’s more,the different bus voltage values and three⁃phase voltage imbalance have a great impact on the transient electric field that the above components bear.The electric field simulation results in this paper have certain reference value for improving the electric field distribution inside the switchgear and on⁃site operation and maintenance.