Conceptual design of a compact pulsed power generator for staged Z-pinch experiments*

We have developed the conceptual design of a 500 kJ pulsed power accelerator, called LTDX. This highly efficient generator, based on linear transformer driver (LTD) technology, will enable fusion experiments to be performed using staged Z-pinch (SZP) loads. Five modules, each consisting of five cavities connected in series, transport current to a central vacuum-insulated power flow section and load. Each cavity consists of 20 capacitor-switch units called “bricks” which, owing to their circuit parameters, provide a characteristic 100 ns current rise time without the need of pulse compression. The resulting system, which exploits impedance matching between elements, can produce a peak current of 6-7 MA with an energy delivery efficiency to the load of approximately 30%. We will discuss the integrated use of circuit, 3D electromagnetic, and magnetohydrodynamic (MHD) codes to obtain a high-fidelity generator design. We will also discuss SZP loads optimized for the LTDX generator using the MACH2, TRAC-II, and HYDRA MHD codes.