典型特高压换流阀塔屏蔽装置电场仿真及对比分析

Electric Field Simulation and Comparison of Shielding Apparatus on Typical Types of UHVDC Converter Valve Units

为研究实际阀厅布置中特高压换流阀塔屏蔽装置的电场分布规律,分析了某±800 k V直流输电工程不同阀厅中所用3种典型换流阀塔的结构特点,利用ANSYS仿真软件建立了各种阀塔的电场计算有限元等效模型,同时为考虑实际运行时阀厅内各设备间的相互影响,建立了3种换流阀塔各自所在阀厅的整体模型作为求解区域,计算了额定工况下阀厅内6组换流阀塔1个周期内的电位、电场分布,并对比了3种典型阀塔屏蔽装置的电场分布特点。研究结果表明3种换流阀塔的屏蔽装置在额定工况下表面电场强度最大值分别为1 599、1 007、1 515V/mm,均满足小于2 000 V/mm的控制场强要求;阀层弯边式分体屏蔽装置电场分布的均匀性优于阀层整体屏蔽型与单片式分体屏蔽型。

In order to analyze the electric field distribution of shielding apparatus on UHVDC converter valve unit in actual valve hall arrangement, we analyzed the structure characteristics of three typical types of UHVDC converter valve units in different valve halls of one ±800 kV transmission project. Using the FEM software ANSYS, we built the equiva- lent models of different converter valve units for electric field calculation. Considering the interaction of equipment on electric field distribution in one valve hall, we established 3 whole models of valve halls as the calculation region using different types of converter valve unit, respectively.The potential and electric field distribution of the 6 sets of valve units in each valve hall was calculated under normal operating conditions. And the electric field distribution characteristics of the shielding apparatus on 3 different typical types of valve units were analyzed and compared. The calculation results show that the maximum values of surface electric field strength of shielding apparatus on 3 typical valve unit type are 1 599 V/mm, 1 007 V/mm, 1 515 V/mm, respectively, lower than 2 000 V/mm, the electric-field criteria for design. The electric field uniformity of the shielding apparatus on separated bending tier shielding type valve unit is superior to that on integral tier shielding type and separated board tier shielding type.