Materials, actuators and eddy currents have significant effects on magnetic resonance⁃compatibility under magnetic resonance environment. This paper presented a C type⁃based simulation environment of permanent magnets to investigate the influence of different materials and different working mode ( static and dynamic) on eddy current fields using the finite element method. The reasons why eddy current fields changed with materials and conditions were analyzed and eddy current magnetic intensities in imaging areas were determined. The results showed prelimi⁃narily that:(1) for the same frequency, when phase increases from 0°to 90°, eddy current magnetic intensity un⁃der static state decreases;(2) the dynamic eddy curent magnetic intensity increases with decreasing distance when actuators does not reach imaging area and reaches a peak value near the margin of imaging area; (3) its internal eddy current magnetic intensity gradually decays when actuator centers into the imaging area and keeps a steady state at the center of imaging area.%材料、驱动方式和涡电流对核磁共振兼容性有重要影响。建立了C型永磁体涡流场仿真环境，采用有限元方法分析不同材料、不同工作状态（静态、动态）下涡流场的分布以及变化规律；获得不同材料在成像区域内的涡流场强度。结果表明，同一工作频率下，静态涡流场随相位的不断增大逐渐减小；动态涡流场在未进入成像区域时随距离的减小而增大并在成像区域边缘形成极值；执行机构在进入成像区域时内部涡流场逐渐衰减，处于成像区域中心时达到稳定状态。
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