Analysis and suppression of conducted interference in tokamak accelerator

In Tokamak accelerators, the high-frequency switching-mode power supply (SMPS) causes electromagnetic interference that not only affects the public power system but also results in abnormal operation of other key equipment connected to the common ground terminal, such as the measurement and diagnosis system. In this article, to develop a model of the conducted interference of high-frequency SMPSs, we analyze the use of a biased SMPS configured as a high-voltage direct-current snubber to protect the accelerator and measure the interference in the accelerator to explore the mechanisms that generate differential and common-mode noise. The experiment examines how the electromagnetic-interference filter inhibits the conducted interference that stems from the high-frequency SMPS, and we develop a method to inhibit conducted interference within the standard frequency range. After adjustment, the intensity of the conducted interference significantly declines to the point that it satisfies the current standard of the International Electrotechnical Commission. The predicted effect of this method is consistent with the actual effect. Thus, this method effectively suppresses conducted interference from high-frequency SMPSs and improves the electromagnetic compatibility of the accelerator system.