为控制换流站内输电线路工频电流对阀厅检修大厅内人体、设备、通信系统的干扰，需要在设计时计算检修大厅内的磁场强度,并根据要求设计检修大厅的磁场屏蔽。基于空间坐标矢量公式推导出阀厅内部磁场强度的一般性公式；按照要求对检修大厅进行磁场屏蔽设计；利用软件HFSS模拟验证磁场屏蔽计算方法的正确性。研究结果表明，在检修大厅屏蔽效能要求为40 dB时，大厅侧壁采用5 mm铝质金属板较好；大厅地面采用铜质金属网，网线直径取5 mm，网孔边长取20 mm。

In order to control the interference of power current of transmission line on human body, equipment and communication systems in converter station, the magnetic intensity in maintenance hall should be calculated, and the magnetic shielding should be designed according to the requirements. The general formula of magnetic field intensity in valve hall is derived from space coordinates vector formula. Then the magnetic shielding of maintenance hall is designed according to the requirements. Finally, HFSS software is used to verify the correctness of the calculation method of magnetic shielding. The results show that 5 mm aluminum plate is better for the hall sidewall, when the shielding effectiveness in maintenance hall is demanded to be 40 dB, and copper mesh with side length of 20 mm and mesh wire diameter of 5 mm should be laid on ground.