Study on the changes in the reverse recovery characteristics of high-power thyristor under 14.1 MeV fusion neutron irradiation

• Published in: Fusion engineering and design Vol. 211; p. 114744
• Main Authors: Tong, Wei, Li, Hua, Liu, Dongmei, Wu, Yanan, Xu, Meng, Wang, Kun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2025
• Subjects: High-power thyristor; Neutron irradiation; Quench protection system; Reverse recovery; Tokamak; Tokamak; Neutron irradiation; High-power thyristor; Quench protection system; Reverse recovery
• ISSN: 0920-3796
• DOI: 10.1016/j.fusengdes.2024.114744

•This paper deeply analyzed the microscopic material damage mechanism of high-power thyristor induced by neutron irradiation and its relationship with reverse recovery characteristics.•A high-efficient neutron irradiation experiment is designed and conducted to accurately verify the correctness of the analysis result of the changes in the reverse recovery characteristics of high-power thyristor.•The impact of neutron irradiation on the QPS, which contains multiple thyristors in series, is studied and discussed through system level simulation.•All the study shown in this paper would provide valuable guidelines for the maintenance and renovation of QPS, which will significantly improve the safety of Tokamak devices. When the d-T fusion reaction takes place in a Tokamak, the high-energy neutrons emitted, with an energy of 14.1 MeV, can alter the electrical properties of high-power thyristors in Quench Protection System (QPS). The Reverse Recovery Characteristics (RRC) of High-power Thyristor (HP-SCR) is one of the crucial issues affecting the reliability of QPS. In this paper, the change in the RRC of HP-SCR under 14.1 MeV neutron irradiation is deeply studied. Firstly, the microscopic material damage mechanism of HP-SCR induced by neutron irradiation and its relationship with RRC are deeply analyzed. Secondly, a highly efficient neutron irradiation experiment is designed and conducted to effectively validate the correctness of the theoretical analysis regarding changes in RRC. Finally, the effects of neutron irradiation on the QPS, consisting of multiple thyristors arranged in series, are analyzed and discussed through system-level simulations. The study offers important recommendations for the maintenance and upgrade of QPS, which will greatly enhance the safety of Tokamak devices.