Design of filters for high-current converters in fusion application

Nuclear fusion generators are widely considered one of the most promising approaches to generating clean, reliable, and large-scale energy. They have the potential to meet global energy demands while minimizing environmental impact, making them an important area of scientific and industrial research. To function properly, a fusion reactor requires several programmable high-current power supplies, typically ranging from 30 to 50 kA. These power supplies are essential for producing the magnetic fields required to confine and control plasma within a specific chamber. Without precise control over the plasma, the fusion reaction cannot be sustained or properly regulated, affecting the reactor’s performance. To meet the stringent requirements of these high-current power supplies, power electronics based systems are widely used. These systems, based on semiconductor switching, can efficiently manage the energy required to generate and regulate magnetic fields. However, the switching activity inherent in power electronics causes perturbations on both the source (input) and load (output) sides of the system. These perturbations can lead to operational inefficiencies and reduce the overall stability of the reactor’s power supply system. To reduce these disturbances, passive filters are typically used at both the power supply’s input and output stages. These filters are intended to smooth out the voltage and current waveforms, ensuring that the power supply operates within acceptable limits and has no negative impact on the fusion reactor’s performance. However, because of the high current ratings involved, designing and sizing these filters is difficult. Larger currents require larger and more complex filters, increasing the physical size, cost, and complexity of the entire power supply system. This presents a significant engineering challenge because the space available in fusion facilities is frequently limited and cost-efficiency is critical to making fusion energy commercially feasible. The primary goal of the PhD activity is to investigate and develop industrially viable solutions to reduce the size of these passive filters while maintaining their performance. By reducing the physical dimensions and material costs of the filters, power supplies can become compact, cost-effective, and simple to integrate into large-scale fusion reactors. To accomplish this, various power supply system configurations will be designed, with a focus on optimizing the interaction between the power electronics and the passive filters. These configurations will be validated with simulation models and real-time HIL. The research aims to identify practical solutions that can be applied to real-world fusion reactors, thus advancing nuclear fusion technology and its future role in the global energy landscape.