The magnetic field environment around tokamak devices is very strong, which affects the working characteristics of electrical and electronic devices. For the study of magnetic field interference problems and the qualification test of sensitive devices, an immunity test platform against both D.C. and power-frequency magnetic fields is designed in this paper, including the analysis and design of magnetic field generating coil and the power supply. The rated D.C. and power-frequency magnetic fields of the test coil are 200 mT and 50 mT, respectively, and the field inhomogeneity is 1.1. The electromagnetic design and the thermal design of the test coil are presented. The power supply adopts the three-stage series structure of rectifier, D.C. bus and H-bridge to enable the output of both D.C. and power-frequency currents. As the test requires a wide output current range with a high accuracy, an improved topology is proposed to ensure the stability and accuracy at all test levels. The operation principle and control strategy of the topology are analyzed and presented. The simulation results show that the topology and control strategy meet the design requirements.

中文翻译：

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直流工频磁场抗扰度测试平台分析与设计

托卡马克装置周围的磁场环境非常强，影响电气电子装置的工作特性。针对磁场干扰问题的研究和敏感器件的合格测试，本文设计了一种抗直流和工频磁场的抗扰度测试平台，包括磁场发生线圈和电源的分析和设计。试验线圈的额定直流磁场和工频磁场分别为200 mT和50 mT，场不均匀度为1.1。介绍了测试线圈的电磁设计和热设计。电源采用整流器、直流母线和H桥三级串联结构，可实现直流和工频电流的输出。由于测试需要宽输出电流范围和高精度，因此提出了一种改进的拓扑以确保所有测试级别的稳定性和准确性。分析并提出了该拓扑的工作原理和控制策略。仿真结果表明，该拓扑和控制策略满足设计要求。