The 6th International Conference on Matter and Radiation at Extremes (ICMRE2023)

70 / 2023-04-12 14:37:59

Design for the vacuum insulator stack of 50MA facility

vacuum insulator stack;,flashover probability,electrostatic analyses

Inertial Confinement Fusion Physics > Alternative ICF and pulsed power technology-I

The next generation pulsed power facility was designed to deliver 50MA to the Z-pinch load for inertial confinement fusion research in china. This paper described the vacuum insulator stack of 50 MA facility design and presented the results of electrostatic analyses and flashover probability. The vacuum insulator stack consists of 6 levels (A, B, C, D, E, F) transmitting into the load through a set of Magnetically Insulated Transmission Lines (MITLs). The insulator stack performance was required enough high to avoid flashover and increase the probability of whole system. The stack was designed through considering the pulse voltage, the electric field stress, the pulse duration and grading requirements. The stack each level was configured with 16, 15, 14, 13, 12, 11 insulator rings. The diameter of stack was about 5.5m; the whole height of stack was about 5.7m. The insulator ring material was cross-linked-polystyrene and the grading ring material was hard-coat anodized Aluminum. The maximum average electric field was about 130kV/cm with peak pulse voltage 11.5MV and half width duration 140ns under charging voltage 85kV. The flashover probability of stack was calculated by statistical model considering the multistage factor and circumferential transit time. The calculated results show that the electric field stresses of grading ring was below 300 kV/cm on the vacuum side, below 200 kV/cm on the water side, less than 30 kV/cm at the cathode triple points; the insulator voltages absolute vary was less than 10%; the flashover probability of each level was less than 2%.